A Phase IIa Challenge Study to Assess Efficacy of the Plasmodium Vivax Malaria Vaccine Candidates ChAd63 PvDBP and MVA PvDBP in Healthy Adults Living in the UK
Phase: PHASE2
Conditions: Malaria, Vivax
Sponsor: University of Oxford

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 1 of 128 
 
 
 
 
 
 
 
 
 
A Phase IIa challenge study to assess efficacy of the Plasmodium vivax malaria vaccine 
candidates ChAd63 PvDBP and MVA PvDBP in healthy adults living in the UK 
 
Study Reference: VAC071 
Protocol Version: 9.0 
Date: 14th June 2022 
 
 
IRAS Project ID: 261730 
REC reference: 19/SC/0193 
 
 
Chief Investigator: Angela M. Minassian 
Sponsor: University of Oxford 
 
 
 
 
 
 

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MODIFICATION HISTORY 
Version
Date 
Author(s) 
Modifications 
1.0 
21st March 
2019 
Yrene 
Themistocleous
Thomas 
Rawlinson 
Angela 
Minassian 
Created 
2.0 
 23rd April 
2019 
Yrene 
Themistocleous
Addition of conflict of interest statements for Dr A M 
Minassian and Prof S J Draper 
3.0 
6th June 
2019 
Yrene 
Themistocleous
Angela 
Minassian 
Addition of safety data from the VAC069 study 
Addition of stopping and holding rules 
Removal of barrier methods of contraception as an 
acceptable form of effective contraception, where 
used as the sole contraceptive 
Addition of information relating to concomitant 
medications 
Addition of exclusion criterion regarding receipt of 
licensed vaccines 
Clarification of the definition of SARs and SUSARs 
Correction of typographical errors 
3.1 
26th July 
2019 
Yrene 
Themistocleous
Clarification for CHMI timing at 2-4 weeks post-boost 
vaccination (MVA PvDBP) 
3.2 
20th 
January 
2020 
Yrene 
Themistocleous
Minor corrections to schedule of visits table 
(clarifying total immunology bleed and volume of 
blood draw for haematology test at screening 
corrected to 4mL from 5mL) 
4.0 
12th 
February 
2020 
Yrene 
Themistocleous
Changes to exclusion criteria relating to haemoglobin 
levels at screening and prior exposure to 
immunoglobulins 
Exclusion criteria relating to prior immunoglobulin 
exposure amended. 
Removal of thick blood film as diagnostic measure 
during CHMI for Group 2 
Addition of repeat blood-borne viral screen at C+96  
Updates and corrections to schedule of visits and 
bleed volumes, including reduction of maximal blood 
draw for Group 2 

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Addition of timing windows for recording physical 
observations on day of challenge 
Clarifications to collection of adverse event data  
Potential for use of alternative antiemetic to cyclizine
Removal of AEs of special interest 
Change to group sizes (target range now specified) 
Clarification regarding timing of screening visits and 
for re-screening procedures for participants screened 
>90 days prior to enrolment 
CRP added as an exploratory measure 
Local safety monitor takes on role previously taken 
by local safety committee  
5.0 
26th 
November 
2020 
Mimi Hou 
Angela 
Minassian 
Change of vaccination schedule for group 2 due to 
temporary trial halt. Justification for addition of 
second dose of ChAd63 PvDBP 
Addition of Group 3, to be recruited if fewer than 6 
participants complete the study in Group 2 
C-1 visit changed to C-2. Extension of time window 
for study visits. 
Changes to trial procedures to account for possibility 
of COVID-19 infection during CHMI. Addition of 
COVID-19 PCR swab test prior to challenge and on 
day of malaria diagnosis. Guidance on testing for 
COVID-19 if fever post vaccination and post 
challenge. 
Added option of using Malarone as first line anti-
malaria treatment 
Addition of serum bhCG to C+28/day of malaria 
diagnosis  
Clarification that G6PD, DARC and 
haemoglobinopathy screen are only done at NHS labs
Correction of typographical errors 
Addition of retrospective COVID-19 serology testing 
for exploratory analysis of effects of COVID 
serostatus on vaccine immunogenicity 
6.0 
4th January 
2021 
Mimi Hou 
Clarification of exclusion criteria regarding 
concomitant vaccinations and addition of specific 
criteria relating to licensed COVID-19 vaccination 
Extension of time window for MVA PvDBP 
vaccinations 

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Addition of section on administration of concomitant 
COVID-19 vaccination 
7.0 
21st April 
2021 
Mimi Hou 
Addition of exclusion criteria on concomitant COVID-
19 vaccination around time of CHMI.  
Shortened time window of when COVID-19 
vaccination can be given following malaria 
vaccination to aid scheduling of COVID-19 
vaccinations. 
Updated section on Conduct of CHMI in the context 
of COVID-19 pandemic. 
Addition of safety information on risk of blood clots 
with viral vectored COVID-19 vaccines in sections 4.5 
and 8.5.2 
8.0 
19th July 
2021 
Baktash 
Khozoee 
Mimi Hou 
For Groups 2 and 3 - post-challenge follow-up visits 
changed to once a day until parasite count reaches 
>1000 genome copies/ml, then to continue twice a 
day visits until diagnosis. Latest day of treatment 
reduced to C+21. 
Addition of section 11.5.4 on initial follow-up visits 
post antimalarial treatment. For Groups 2 and 3 - 
change of post malaria treatment visit from T+2 to 
T+3 
Correction of error in lumefantrine dose in section 
8.5.5  
Addition of reticulocyte count to FBC taken at C-2 
visit. 
Correction of errors in protocol – only weight taken 
at C-2 visit.  
Changed Senior Laboratory Investigator address. 
Addition of New Biochemstry Building as location for 
processing of research bloods.  
Updated compensation table 
9.0 
14th June 
2022 
Mimi Hou 
Samples will now be stored long term under 
University of Oxford’s HTA license at Department of 
Biochemistry instead of Oxford Vaccine Centre 
Biobank. 
 
 
 

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A Phase IIa challenge study to assess efficacy of the Plasmodium vivax malaria vaccine 
candidates ChAd63 PvDBP with MVA PvDBP in healthy adults living in the UK 
Study Code:  VAC071 
 
Chief Investigator 
Dr Angela M Minassian 
 
 
 
 
 
 
Principal Investigator 
 
 
 
 
 
 
Trial sites 
 
 
 
 
Centre for Clinical Vaccinology and Tropical Medicine, 
Jenner Institute, University of Oxford,  
Churchill Hospital, Old Road, Headington, 
Oxford, OX3 7LE 
Email: angela.minassian@ndm.ox.ac.uk 
 
Prof Simon J Draper  
New Biochemistry Building, 
Department of Biochemistry, 
South Parks Road 
Oxford, OX1 3QU 
Email: simon.draper@bioch.ox.ac.uk 
 
Centre for Clinical Vaccinology & Tropical Medicine 
Jenner Institute, University of Oxford,  
Churchill Hospital, Old Road, Headington,  
Oxford, OX3 7LE 
PI at Site: Dr Angela M Minassian 
 
Sponsoring Institution 
 
 
 
 
University of Oxford 
Clinical Trials and Research Governance,  
Research Services 
University of Oxford 
Joint Research Office 
Boundary Brook House 
Churchill Drive 
Headington 
OX3 7GB 
Tel: 01865 616480  

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Email: ctrg@admin.ox.ac.uk 
 
External Monitor  
 
 
 
 
 
Clinical Trials and Research Governance (CTRG) 
Research Services 
University of Oxford 
Joint Research Office 
Boundary Brook House 
Churchill Drive 
Headington 
OX3 7GB 
Tel: 01865 616480 
 
Local Safety Monitor  
 
Prof Brian Angus 
Centre for Clinical Vaccinology and Tropical Medicine, 
Churchill Hospital, Old Road, Headington, 
Oxford, OX3 7LE 
Tel: 01865 220289 
Email: brian.angus@ndm.ox.ac.uk 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Confidentiality Statement 
This document contains confidential information that must not be disclosed to anyone other 
than the Sponsor, the Investigator Team, and members of the Independent Ethics Committee.  
This information cannot be used for any purpose other than the evaluation or conduct of the 
clinical investigation without the prior written consent of Dr Angela M. Minassian. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Investigator Agreement 
“I have read this protocol and agree to abide by all provisions set forth therein. 
I agree to comply with the principles of the International Conference on Harmonisation Tripartite 
Guideline on Good Clinical Practice.”   
Dr Angela M. Minassian 
 
 
 
23/06/2022 
Chief Investigator 
 
 
Investigator Signature 
 
Date  
 
Conflict of Interest 
1. “According to the Declaration of Helsinki, 2008, I have read this protocol, and declare the 
following conflict of interest” 
Details: I have a family member who is an inventor on patents for adenovirus-based vaccines. 
 
Dr Angela M. Minassian 
 
 
 
 
23/06/2022 
Chief Investigator 
 
 
Investigator Signature 
 
Date  
 
 
2.  “According to the Declaration of Helsinki, 2008, I have read this protocol, and declare the 
following conflict of interest” 
Details: I am a named inventor on patents relating to adenovirus-based vaccines. 
 
Prof Simon J. Draper 
 
 
 
 
23/06/2022 
Principal Investigator 
 
 
Investigator Signature 
 
 
Date  
 
 
 
 
 
 

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Table of Contents 
Modification History ...................................................................................................................... 2 
1 Synopsis ................................................................................................................................... 15 
2 Abbreviations ........................................................................................................................... 17 
3 Background & Rationale ........................................................................................................... 19 
3.1 
Impact of P. vivax malaria and the need for a vaccine .................................................. 19 
3.2 
Lifecycle of the Plasmodium vivax malaria parasite ...................................................... 20 
3.3 
 Challenges and directions in P. vivax vaccine development ......................................... 21 
3.4 Rationale for a blood stage vaccine against Plasmodium vivax malaria .............................. 23 
3.5 PvDBP as an Antigen .......................................................................................................... 24 
3.6 Simian adenoviruses as vectors .......................................................................................... 25 
3.7 MVA as a Vector (see also IB for MVA PvDBP) .................................................................... 26 
4 ChAd63 PvDBP and MVA PvDBP Vaccine Development ............................................................ 29 
4.1 Characteristics of ChAd63 PvDBP ....................................................................................... 29 
4.2 Characteristics of MVA PvDBP ............................................................................................ 29 
4.3 ChAd63 and MVA encoding PvDBP in pre-clinical studies ................................................... 29 
4.4 Clinical experience with ChAd63 PvDBP and MVA PvDBP in a Phase Ia clinical trial (VAC051)
 ................................................................................................................................................ 29 
4.5 Clinical experience with administering multiple doses of ChAd vectored vaccines ............. 30 
4.6 Concomitant COVID-19 vaccinations .................................................................................. 31 
5 Controlled human malaria infection ......................................................................................... 32 
5.1 
Controlled human malaria infection studies ................................................................. 32 
5.1.1 Microbial challenge studies of human volunteers ........................................................ 32 
5.1.2 
Controlled human malaria infection with Plasmodium falciparum ........................... 32 
5.1.3  
Controlled human malaria infection with Plasmodium vivax ................................ 32 
5.1.4 
P. vivax sporozoite challenge in the modern era ...................................................... 33 
5.1.4 
P. vivax challenge for assessment of vaccine efficacy ............................................... 34 
5.1.5 
Modern blood-stage controlled human P. vivax infection ........................................ 37 
5.1.6 
Rationale for blood-stage controlled human malaria infection ................................. 38 
5.2 Cryopreserved Plasmodium vivax blood inoculum ............................................................. 39 
5.2.1 
Source and preparation of the cryopreserved inoculum ........................................... 39 
5.2.2 
Collection of P. vivax infected erythrocytes .............................................................. 39 
5.2.3 
Cryopreservation and storage of blood bank ............................................................ 40 
5.2.4 
Infectivity and characterisation of parasite stock ..................................................... 40 

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5.2.5 
Testing of source patient and blood donors for blood-borne and mosquito-borne 
infections ............................................................................................................................. 40 
5.2.6 
Sterility and screening for blood-borne infections of cryopreserved blood bank ...... 42 
5.2.7 
Determination of safety, feasibility and dose of cryopreserved P. vivax inoculum .... 42 
5.3 
Conduct of CHMI trials ................................................................................................. 48 
5.3.1 Standardisation of CHMI studies .................................................................................. 48 
5.3.2 Ethical considerations of CHMI trials ........................................................................... 48 
5.3.3 
Clinical presentation post-CHMI ............................................................................... 49 
5.3.4 
Oxford’s experience conducting CHMI trials ............................................................. 49 
5.3.5 
Conducting CHMI in the context of the COVID-19 pandemic .................................... 50 
6 Investigational products ........................................................................................................... 53 
6.1 ChAd63 PvDBP ................................................................................................................... 53 
6.2 MVA PvDBP ........................................................................................................................ 53 
6.3 Storage of Vaccines ............................................................................................................ 53 
6.4 Administration of Vaccines ................................................................................................ 53 
6.5 Minimising environmental contamination with Genetically Modified Organisms (GMO) ... 53 
6.6 Vaccine Supply ................................................................................................................... 53 
7 Objectives and endpoints ......................................................................................................... 54 
7.1 Primary Objectives ............................................................................................................. 54 
7.2 Primary Outcome Measures ............................................................................................... 54 
7.3 Secondary Objectives ......................................................................................................... 54 
7.3.1 Secondary Safety Outcome Measures ............................................................................. 54 
7.3.2 
Secondary Immunological Outcome Measures ............................................................ 55 
8 Description and justification of study design ............................................................................ 56 
8.1 
Study rationale ............................................................................................................ 56 
8.2  
Study Overview ............................................................................................................ 56 
8.3 
Study groups ................................................................................................................ 57 
8.3.1 Group 1 ....................................................................................................................... 57 
8.3.2 Group 2 ....................................................................................................................... 58 
8.3.3 Group 3 ....................................................................................................................... 58 
8.3.4 Control groups during challenge .................................................................................. 58 
8.4 
Duration of study ......................................................................................................... 59 
8.4.1 
Definition of the start and end of the trial ................................................................ 59 
8.4.2 Duration of volunteer participation ............................................................................. 59 
8.5 
Potential risks for volunteers ....................................................................................... 59 

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8.5.1 
Phlebotomy ............................................................................................................. 59 
8.5.2 Vaccinations ................................................................................................................ 60 
8.5.3 
Risk of Infection with Blood Borne Organisms .......................................................... 61 
8.5.4 
Plasmodium vivax infection ...................................................................................... 62 
8.5.5 
Medications dispensed to volunteers in course of trial ............................................ 63 
8.5.6 
Risk of reaction to the blood sample ........................................................................ 64 
8.6 
Potential benefits for volunteers .............................................................................. 64 
9 Recruitment and withdrawal for trial volunteers ...................................................................... 65 
9.1 
Informed consent ........................................................................................................ 65 
9.1.1 
Informed consent ..................................................................................................... 65 
9.1.2 
Informed consent questionnaire .............................................................................. 66 
9.2  
Inclusion and exclusion criteria .................................................................................... 66 
9.2.1 
Inclusion criteria ...................................................................................................... 66 
9.2.2 
Exclusion criteria ...................................................................................................... 67 
9.2.3 
Prevention of ‘Over Volunteering’ ............................................................................ 68 
9.2.4 Vaccination and re-vaccination exclusion criteria ........................................................ 68 
9.2.5 
Exclusion criteria on day of CHMI ............................................................................. 69 
9.2.6 
Concomitant medications ........................................................................................ 69 
9.3 
Withdrawal of volunteers ............................................................................................ 70 
9.4 
Pregnancy .................................................................................................................... 71 
10 Controlled Blood-Stage Malaria Infection Inoculum ................................................................ 72 
10.1 
Preparation of the inoculum ........................................................................................ 72 
10.2 
Administration of the inoculum ................................................................................... 72 
11 Treatment of trial volunteers .................................................................................................. 73 
11.1 
Trial sites ..................................................................................................................... 73 
11.2 
Study procedures ......................................................................................................... 73 
11.2.1 
Observations ........................................................................................................ 73 
11.2.2 
Blood tests ........................................................................................................... 73 
11.2.3 
 Urinalysis ............................................................................................................. 74 
11.2.4 
 Electrocardiogram ............................................................................................... 74 
11.2.5 Vaccinations .............................................................................................................. 75 
11.2.6 Management of post-vaccination fevers .................................................................... 75 
11.2.7 Diary card .................................................................................................................. 76 
11.2.8 
SARS-COV-2 PCR swab .......................................................................................... 76 
11.3 
Study visits ................................................................................................................... 76 

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11.3.1 
Screening visits ..................................................................................................... 76 
11.3.2 Enrolment and first vaccination with ChAd63 PvDBP (D0) .......................................... 77 
11.3.3 Group 2 only - second vaccination with ChAd63 PvDBP (PB0) .................................... 77 
11.3.4 Reviews post-vaccination on days 1, 3, 7, 14 and 28 (or PB1, PB3, PB7, PB14 and PB28 
for Group 2) ......................................................................................................................... 77 
11.3.5 Vaccination with MVA PvDBP (day 56 or PB56 for Group 2) ....................................... 78 
11.3.6 Reviews post-vaccination on days 57, 59, 63, and 70 (or PB57, PB59, PB63 and PB70 
for Group 2) ......................................................................................................................... 78 
11.3.7 
Two days before CHMI (C-2 (±1)) .......................................................................... 78 
11.3.8 
Day of CHMI (C0) .................................................................................................. 78 
11.3.9 
Days 1-6 post-CHMI (C+1 – C+6) ........................................................................... 79 
11.3.10 Days 7-9 post-CHMI (C+7 – C+28) (Group 1 only) ..................................................... 80 
11.3.11 Days 7-21 post-CHMI (C+7 – C+21) – Groups 2 and 3 ............................................... 80 
11.4 
Algorithm for initiation of treatment ........................................................................... 81 
11.4.1 Algorithm for initiation of treatment for Group 1 ...................................................... 81 
11.4.2 Algorithm for initiation of treatment for Group 2 and 3 ............................................. 84 
11.4.3 Participants with fever post malaria challenge and COVID-19 testing ........................ 87 
11.5 
Malaria management ................................................................................................... 88 
11.5.1 Riamet ....................................................................................................................... 88 
11.5.2 
Malarone ............................................................................................................. 89 
11.5.3 
Malaria management – supportive medications ................................................... 89 
11.5.4 
Follow-up after commencing malaria treatment .................................................. 89 
11.5.5 
Criteria for inpatient transfer to the NHS ............................................................. 89 
11.6 
Safety measures for conduct of CHMI .......................................................................... 90 
11.6.1 
Measures to be taken if a volunteer goes missing post-CHMI ............................... 91 
11.7 
Follow-up post-treatment ............................................................................................ 91 
11.7.1 
Six days after initiation of treatment (T+6) ........................................................... 91 
11.7.2 
Nine days after initiation of treatment (T+9) ........................................................ 91 
11.7.3 Day 56 post CHMI (C+56) ........................................................................................... 91 
11.7.4 
Day 96 post CHMI (C+96) ..................................................................................... 91 
11.7.5 
Day 276 post CHMI (C+276).................................................................................. 91 
12 Assessment of Safety ............................................................................................................ 103 
12.1 Interim Safety Review .................................................................................................... 103 
12.2 Definitions ..................................................................................................................... 103 
12.2.1 Adverse Event (AE) .................................................................................................. 103 
12.2.2 Adverse Reaction (AR) ............................................................................................. 103 

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12.2.3 Unexpected Adverse Reaction ................................................................................. 103 
12.2.4 Serious Adverse Event (SAE) .................................................................................... 104 
12.2.5 Serious Adverse Reaction (SAR) ............................................................................... 104 
12.2.6 Suspected Unexpected Serious Adverse Reaction (SUSAR) ...................................... 104 
12.2.6 Foreseeable Adverse Reactions ............................................................................... 104 
12.2.7 Other Foreseeable Medical Occurrences ................................................................. 104 
12.2.8 Expected Serious Adverse Events............................................................................. 105 
12.3 Causality Assessment ..................................................................................................... 105 
12.4 Reporting Procedures for All Adverse Events ................................................................. 106 
12.4.1 Reporting Procedures for Serious AEs (see SOP OVC005 Safety Reporting) .............. 107 
12.4.2 Reporting Procedures for SUSARS ............................................................................... 108 
12.4.3 Development Safety Update Report ............................................................................ 108 
12.4.4 Procedures to be followed in the event of abnormal findings ..................................... 108 
12.5 Local Safety Monitor ...................................................................................................... 108 
12.6 Safety Stopping/Holding Rules ....................................................................................... 109 
12.6.1 Group 1 holding rules (applies to further vaccinations in Groups 1 and 2) ............... 109 
12.6.2 Holding criteria for enrolment of Group 2 volunteers (applies to Group 2 only) ...... 110 
12.6.3 Groups 2 and 3 vaccination holding rules (applies to Group 2 and 3 only) ............... 110 
12.6.4 Individual stopping rules .......................................................................................... 111 
13 Statistics ............................................................................................................................... 113 
13.1  
Sample size ................................................................................................................ 113 
14 Quality control and quality assurance procedures ................................................................ 115 
14.1  
Investigator procedures ............................................................................................. 115 
14.2 
Monitoring ................................................................................................................. 115 
14.3 
Modification to protocol ............................................................................................ 115 
14.4 
Protocol deviation...................................................................................................... 115 
14.5 
Audit & inspection ..................................................................................................... 115 
14.6 
Serious breaches ........................................................................................................ 115 
12.7 
Trial progress ............................................................................................................. 116 
12.8 
Publication policy ....................................................................................................... 116 
12.9 
Intellectual Property .................................................................................................. 116 
13 Ethics .................................................................................................................................... 117 
13.1 
Declaration of Helsinki ............................................................................................... 117 
13.2 
Guidelines for good clinical practice ........................................................................... 117 
13.3 
Approvals ................................................................................................................... 117 

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13.5 
Volunteer confidentiality ........................................................................................... 117 
14 Data handling and record keeping ........................................................................................ 118 
14.1 
Data handling............................................................................................................. 118 
14.2 
Record keeping .......................................................................................................... 118 
14.3 
Source data and electronic case report forms (eCRFs) ............................................... 118 
14.4 
Data protection .......................................................................................................... 118 
15 Financing and insurance ....................................................................................................... 119 
15.1 
Financing ................................................................................................................... 119 
15.2 
Insurance ................................................................................................................... 119 
15.3 
Compensation............................................................................................................ 119 
16 Appendices ........................................................................................................................... 120 
18 References ........................................................................................................................... 121 
 
 
 
 
 
 
 
 
 
 
 

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1 SYNOPSIS 
Title 
A Phase IIa challenge study to assess efficacy of the Plasmodium vivax 
malaria vaccine candidates ChAd63 PvDBP and MVA PvDBP in healthy 
adults living in the UK 
Trial Centre 
Clinical Centre for Vaccinology and Tropical Medicine, Churchill Hospital, 
Old Road, Headington, Oxford, OX3 7LE, UK  
Trial Identifier 
VAC071     
Clinical Phase  
Phase IIa 
Design 
Open label, Phase IIa, controlled human malaria infection (CHMI) study 
Population 
Healthy adults aged 18 – 45 years 
Sample Size 
Total: 13-19 volunteers 
Group 1: 3 volunteers receiving 5 x 1010 vp ChAd63 PvDBP and 2 x 108 pfu 
MVA PvDBP 8 weeks later, in a heterologous prime-boost regimen, 
followed by blood-stage CHMI 2-4 weeks later. 
Group 2: up to 10 volunteers receiving one dose of 5 x 1010 vp ChAd63 
PvDBP, 12-18 months later receiving a second dose of 5 x 1010 vp ChAd63 
PvDBP and 8 weeks later 2 x 108 pfu MVA PvDBP, followed by blood-stage 
CHMI 2-4 weeks later. 
Group 3: if fewer than 6 volunteers complete the study in Group 2, then 
new volunteers will be recruited into Group 3, to make up a total of 6 
volunteers between Groups 2 and 3 who complete all vaccinations and 
CHMI. Volunteers in Group 3 will receive 5 x 1010 vp ChAd63 PvDBP and 2 x 
108 pfu MVA PvDBP 8 weeks later, in a heterologous prime-boost regimen, 
followed by blood-stage CHMI 2-4 weeks later. 
Infectivity controls, receiving no vaccinations, will be recruited as part of 
another study (VAC069) and undergo CHMI in parallel with each of Groups 
1, 2 and 3 
Follow-up 
duration 
Participants will be followed for 1 year from enrolment in Groups 1 and 3. 
Participants will be followed for 2 to 2.5 years from enrolment in Groups 2. 
Planned trial 
period  
2.5 to 3 years from the site initiation visit 
Primary Objectives To assess efficacy of the ChAd63 and MVA PvDBP vaccines, administered in 
a heterologous prime-boost regimen, as assessed by a reduced parasite 

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multiplication rate in vaccinated subjects following a blood-stage parasite 
inoculum 
Secondary 
Objectives 
 
 
To assess safety and tolerability of the ChAd63 and MVA PvDBP vaccine 
candidates, administered in a heterologous prime-boost regimen in a CHMI 
study in healthy volunteers 
To assess the humoral and cellular immunogenicity of ChAd63 and MVA 
PvDBP vaccine candidates, administered in a heterologous prime-boost 
regimen 
To assess immunological readouts for association with a reduced parasite 
multiplication rate 
Investigational 
Products 
1. ChAd63 PvDBP 
2.   MVA PvDBP 
Form 
Liquid 
Dose 
ChAd63 PvDBP: 5 x 1010 vp 
MVA PvDBP:  2 x 108 pfu 
Route 
Intramuscular injection in the deltoid region of the arm 
 
 

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2 ABBREVIATIONS 
ACT 
 
  
Artemisinin-based combination therapies 
AE 
 
 
Adverse event 
AR 
 
 
Adverse reaction 
CBF  
 
 
Clinical Bio-Manufacturing Facility 
CCVTM 
 
Centre for Clinical Vaccinology and Tropical Medicine 
CHMI  
 
Controlled human malaria infection 
CI 
 
 
Chief Investigator 
CMV 
 
 
Cytomegalovirus 
CRF 
 
 
Case Report Form or Clinical Research Facility 
CTRG  
 
Clinical Trials Research Governance 
CYP2D6 
 
Enzyme predicting Primaquine metabolism – Cytochrome P450 2D6 
DARC  
 
Duffy Antigen Receptor for Chemokines 
DFA 
 
 
Direct Feeding Assay 
DSUR  
 
Development Safety Update Report 
EBV 
 
 
Epstein-Barr Virus 
ELISA  
 
Enzyme linked immunosorbent assay 
ELISPOT 
 
Enzyme linked immunospot assay 
EPI 
 
 
Expanded Programme of Immunisation 
FDA 
 
 
United States Food and Drug Administration 
GCP 
 
 
Good Clinical Practice 
GMP  
 
Good Manufacturing Practice 
HBsAg  
 
Hepatitis B surface antigen 
HCV 
 
 
Hepatitis C virus 
HIV 
 
 
Human Immunodeficiency virus 
HTLV  
 
Human T cell Lymphotrophic virus 
HLA 
 
 
Human Leukocyte Antigen 
ICH 
 
 
International Conference on Harmonisation 
IFN-

Interferon-gamma 
IM 
 
 
Intramuscular 
IMP 
 
 
Investigational Medicinal Product 
LPS 
 
 
Lipopolysaccharide 
LSM 
 
 
Local Safety Monitor 
MFA 
 
 
Membrane Feeding Assay 
MHRA  
 
Medicines and Healthcare products Regulatory Agency 

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MRC 
 
 
Medical Research Council 
g 
 
 
Microgram 
NIHR  
 
National Institute for Health Research  
pIMD  
 
potential Immune-Mediated Diseases 
PCR 
 
 
Polymerase Chain Reaction 
PIS 
 
 
Participant Information Sheet 
PMR 
 
 
Parasite multiplication rate 
PvDBP_RII 
 
Plasmodium vivax Duffy Binding Protein Region II 
QP 
 
 
Qualified Person 
qPCR  
 
Quantitative polymerase chain reaction 
RAS 
 
 
Radiation-attenuated sporozoite 
RUNMC 
 
Radboud University Nijmegen Medical Center 
REC 
 
 
Research Ethics Commitee 
SAE 
 
 
Serious Adverse Event 
SAR 
 
 
Serious Adverse Reaction 
SOP 
 
 
Standard Operating Procedure 
SUSAR  
 
Suspected Unexpected Serious Adverse Reaction 
TMF 
 
 
Trial Master File 
UOXF  
 
University of Oxford 
USMMVP 
 
United States Military Malaria Vaccine Program 
VLP 
 
 
Virus-like particle 
WHO  
 
World Health Organisation 
WTCRF 
 
Wellcome Trust Clinical Research Facility 
 

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3 BACKGROUND & RATIONALE 
3.1 
Impact of P. vivax malaria and the need for a vaccine 
Plasmodium vivax (P. vivax) is one of the five Plasmodium species known to cause human malaria 
and accounts for the most cases of non-P. falciparum malaria worldwide. Geographically, it is the 
most widespread human malarial infection and approximately 2.5 billion people are at risk of 
contracting the infection in endemic areas [1]. It is estimated over one third of malaria cases 
outside of the African continent are due to P. vivax and that it accounts for 74% of malaria cases 
in the Americas, 37% in South-East Asia and 31% in the Eastern Mediterranean WHO regions.  
The burden is highest in Afghanistan, Ethiopia, India, Indonesia and Pakistan, which together 
account for 82% of P. vivax cases[2]. 
P. vivax has long been considered, and termed, ‘benign’ malaria, but more recently large case 
series demonstrate that P. vivax infection is associated with significant morbidity and mortality. 
Complications reported include severe anaemia, respiratory and hepatic dysfunction, severe 
thrombocytopenia and coagulopathies, such as disseminated intravascular coagulation (DIC) [3]. 
P. vivax infection has also been associated with important sequelae for maternal and foetal 
health, correlating with increased rates of low birthweight, preterm delivery, and reduced foetal 
growth, as well as maternal and foetal deaths [4].  
The socio-economic impact of this infection is not known, but in terms of overall global cost due 
to lost productivity this is estimated at US$ 1.4 to 4.0 billion per year [5]. Those affected by P. 
vivax malaria are typically poor with inadequate access to affordable healthcare and with little 
financial reserve, perpetuating the cycle of poverty [6].  
Clinical cases not only result from primary infection but also relapses, which occur weeks to years 
after primary infection. Relapses are due to the ability of the P. vivax parasite to remain dormant 
in the liver in the hypnozoite stage, a lifecycle stage not seen with P. falciparum malaria [5]. 
Standard schizonticidal regimes are not effective against hypnozoites. Radical cure of dormant 
parasites requires therapy with the 8-aminoquinolone primaquine, currently the only licensed 
hypnozoitcidal anti-malarial, although tafenoquine, a new drug of the same class, given as a 
single dose, has recently been FDA-approved for adults in the United States. However, both 8-
aminoquinolones carry a significant risk of severe haemolytic anaemia in individuals who are 
deficient in the glucose-6-phosphate dehydrogenase enzyme (G6PD), an inherited X-linked red 
blood cell enzyme disorder common in tropical and sub-tropical areas [7]. More recently, the 
importance of the cytochrome P450 enzyme, CYP2D6 in metabolism of primaquine to the active 
metabolite has been recognised [8, 9]. A common polymorphism in the CYP2D6 gene for the 
cytochrome P450 enzyme results in poor conversion of primaquine to the active form, resulting 
in higher treatment failure rates. It is estimated that these two factors combined may make 
nearly 40% of the population at risk of P. vivax infection ineligible for primaquine therapy [7].   
Control of P. vivax is also challenging, with re-emergence in areas where it has previously been 
eradicated. P. vivax is epidemiologically and biologically different to P. falciparum and control 
methods developed for P. falciparum are less efficient for P.vivax malaria [10-13]. Control efforts 
are complicated by multiple factors including difficulty detecting asymptomatic infection, resistance 
to antimalarials, a lack of understanding of parasite biology, early gametocytogenesis and relapses 
[14, 15]. Recent calls for control and ‘eradication’ of malaria worldwide [16] have focused 
attention on this neglected disease and the need for development of an effective P. vivax vaccine 
to be used alongside current control methods [17]. 
Consequently, the revised Malaria Vaccine Technology Roadmap to 2030 [17] now recognises the 
importance of P. vivax and calls for a vaccine to achieve 75% efficacy over two years – equally 

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Page 20 of 128 
weighted with P. falciparum in an era of renewed political will to move towards malaria 
elimination and eradication. 
However, unlike P. falciparum, to date there has been relatively little research into this malaria 
species and one of the limiting factors has been the inability to culture P. vivax parasites in vitro 
over a prolonged period of time. More recently, research into P. vivax malaria has increased with 
candidate vaccines being developed and taken forward to clinical trial [18, 19]. Yet none of these 
vaccines have progressed past a Phase IIa trial, and options for assessing the immune responses 
to new candidates are extremely limited.  
3.2 
Lifecycle of the Plasmodium vivax malaria parasite 
The lifecycle of P. vivax is complex, involving both the vector (the Anopheles mosquito) and the 
human host (Figure 1). Sporozoites are injected into the human host when the female Anopheles 
mosquito takes a blood meal. From here they migrate within minutes to the liver, where they 
invade hepatocytes and the schizont develops (liver-stage). The mature schizont ruptures after 
around 7 days, releasing merozoites into the blood stream, which invade reticulocytes 
preferentially (unlike P. falciparum which invades all erythrocytes). As well as developing 
schizonts in the liver, P. vivax forms hypnozoites, a dormant stage which develop into schizonts 
weeks to years later, rupturing when mature and releasing merozoites to cause blood-stage 
malaria. It is this stage of the lifecycle that is responsible for relapse.  
Once merozoites have invaded reticulocytes they are termed trophozoites, and again mature 
into schizonts which release merozoites after 2 days. These merozoites go on to infect other 
reticulocytes, and the blood-stage cycle continues. A subset of trophozoites develop into 
gametocytes, the sexual-stage of the malaria lifecycle, rather than forming schizonts. This occurs 
early in blood-stage infection with P. vivax, unlike P. falciparum. These are taken up by the 
mosquito in a blood meal. The sporogonic cycle takes place within the mosquito. The 
microgametocyte (male) exflagellates and enters the macrogametocyte (female) to form a 
zygote within the mosquito midgut. Zygotes become motile (ookinetes) and penetrate the 
midgut wall where they develop into oocysts. These rupture, release sporozoites which migrate 
to the mosquito salivary glands ready to be injected when the mosquito takes another blood 
meal [20]. 
The liver-stage of infection is asymptomatic. Symptoms, and subsequent complications, develop 
during the blood-stage. 
 

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Figure 1: Lifecycle of P. vivax malaria 
 
3.3 
 Challenges and directions in P. vivax vaccine development  
The unique characteristics of P. vivax pose some specific challenges in studying its biology and 
designing strategies to control it. For example, the lack of a method for continuous culture of P. 
vivax blood-stages makes it difficult to perform in vitro growth inhibition assays to identify 
synergistic combinations of blood-stage antigens that can be targeted to inhibit P. vivax blood- 
stage growth with high efficiency. Several groups have recently succeeded in establishing short-
term P. vivax culture for invasion assays using enriched reticulocytes from cord blood [21], but 
such methods are still dependent on access to fresh P. vivax isolates from malaria patients 
limiting the routine use of such assays to endemic regions. In the absence of a P. vivax blood-
stage culture system, production of infected mosquitoes for sporozoite- or transmission-stage 
studies also requires access to P. vivax patients in endemic areas. In order to study hepatocyte 
invasion stages of P. falciparum as well as P. vivax, attempts have been made to establish in vitro 
liver models [22, 23]. In addition, a reliable humanised mouse model for P. vivax liver-stages is 
now available [24]. These approaches, together with the P. cynomolgi model in non-human 
primates will help to identify and test novel drugs and vaccines targeting hepatocyte stages [25]. 
Studies on expression of parasite proteins in hypnozoites will determine if these latent stages can 
also be targeted with novel drugs and vaccines.  
Currently, the two most clinically advanced P. vivax vaccine candidates are both subunit vaccines 
based on P. vivax circumsporozoite protein (PvCSP), an analogue of the P. falciparum pre-

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Page 22 of 128 
erythrocytic target, which have both have reached Phase IIa efficacy testing in mosquito-bite 
delivered, sporozoite P. vivax CHMI. The vivax malaria protein 1 (VMP001) vaccine, formulated in 
the GSK Adjuvant System AS01B, was shown to be well tolerated and immunogenic in healthy US 
volunteers. However, following CHMI at 14 days after the third immunisation, the vaccine failed 
to induce any sterile protection, although a small but significant delay in parasitaemia was seen 
in 59% (16/27) volunteers compared to non-vaccinated controls. A Phase IIa trial assessing 
efficacy of another PvCSP based candidate (long synthetic peptide CS derivatives, formulated in 
Montanide ISA 51) in mosquito bite challenge is also now complete, with results currently 
awaited (Clinicaltrials.gov identifier NCT02083068).  
To date, repeated exposure to radiation-attenuated sporozoites (RAS) delivered by mosquito bite 
has been the only “immunisation” strategy to demonstrate any protective efficacy in P. vivax 
CHMI. Protection following exposure to irradiated sporozoites was first demonstrated in 2 
volunteers in the 1970’s in Maryland but this result was not replicated in larger numbers until a 
recent study in Cali, Colombia [26, 27]. In the Cali study, twelve Duffy positive participants were 
exposed to seven “immunisations”, receiving median of 434 infective bites (range 362–497) from 
irradiated, infected mosquitoes over 56 weeks. Volunteers were then treated with chloroquine 
and primaquine to clear any malaria infections that may have developed during the 
immunisation phase, before challenge at 8 weeks after the last RAS exposure. Immunised 
participants underwent CHMI alongside two Duffy positive negative controls, who were exposed 
to non-irradiated, non-infected mosquitoes and seven Duffy negative positive controls who had 
received the same immunisation regime. Sterile efficacy was demonstrated in 42% (5/12) of 
Duffy positive participants, interestingly, all of which were female (5/7 female participants vs.0/5 
males) [27]. Given the apparent high dose exposure required to afford this level of protection, 
and the current lack of availability of cryopreserved, purified P. vivax sporozoites, this approach 
may be limited as a vaccination strategy but transcriptomic and anti-parasite antibody profiling 
may offer important insights into correlates of protection and new pre-erythrocytic vaccine 
targets.  
Apart from the ChAd63 and MVA PvDBP candidates, the only other P. vivax blood-stage vaccine 
currently in active clinical development is a recombinant protein, called PvDBPII, which targets 
the same cysteine-rich, region II of PvDBP, which serves as the functional receptor-binding 
domain for the essential interaction for reticulocyte invasion with Duffy Antigen Receptor for 
chemokines (DARC). A Phase I trial has demonstrated that the PvDBPII vaccine, formulated 
with the glucopyranosyl lipid adjuvant-stable emulsion (GLA-SE), is safe and induces functional 
strain-transcending antibodies, which inhibit the PvDBP-DARC interaction in vitro[28]. The 
PvDBPII vaccine is currently progressing to efficacy assessment in a Phase IIa challenge trial.    
A single P. vivax transmission-blocking candidate, the recombinant protein Pvs25H, derived 
from the Pvs25 surface antigen of P. vivax ookinetes, has reached Phase I clinical testing. When 
administered in Alhydrogel, the vaccine produced promising transmission blocking activity as 
assessed in a direct membrane feeding assay (DMFA) in some volunteers, however, overall 
induced antibody titres were low [29]. To increase immunogencity, Pvs25H was tested in 
formulation with the stronger water-in-oil adjuvant, Montanide ISA51, but due to concerns 
regarding the both local and systemic reactogenicity of this formulation, including erythema 
nodosum in two individuals, the trial was subsequently halted[30].   
All vaccines currently in clinical development, and almost all those in pre-clinical stages, target 
individual stages of the parasite’s lifecycle and are based on single antigens (Table 1 [18]). 
However, the development of an effective vaccine will likely require combination of multiple 
antigens that provide synergy to achieve high efficacy. For example, achieving high rates of 
blood-stage growth inhibition may require targeting a combination of key blood-stage antigens 

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involved in reticulocyte invasion. In addition, a combination of blood-stage antigens with liver-
stage antigens may be needed to achieve high efficacy, and inclusion of antigens from sexual- 
and mosquito-stages will be needed to inhibit transmission. It is therefore necessary to initiate 
efforts to combine antigens both within and across developmental stages to achieve synergy and 
attain the goal of developing a vaccine for P. vivax malaria with high efficacy. 
3.4 Rationale for a blood stage vaccine against Plasmodium vivax malaria 
The feasibility of a blood-stage vaccine for P. vivax is supported by significant literature. Firstly, 
although the human immune system will attack almost any stage of the parasite life cycle in the 
human host, naturally-acquired immunity appears to primarily target blood-stage infections [31]. 
Naturally acquired immunity develops over time with repeated exposure, to both primary blood-
stage infections and relapse infections in the blood, and individuals with acquired immunity may 
develop asymptomatic infection [5]. This is reflected in the epidemiology of disease; in high-
transmission areas, most infections, and in particular severe infections, are seen in children 
whereas in low-transmission settings the risk of infection, and severe disease, is evenly 
distributed across age groups[32]. Naturally acquired immunity to P. vivax is complex and 
remains incompletely understood, but mechanisms of protection may include antibody mediated 
inhibition of invasion, enhancement of phagocytosis, cellular inhibition and neutralisation of 
malarial toxins produced during schizont rupture, as well as cytokine release [33].  
 
Secondly, malaria disease occurs at the blood-stage of infection. The potential advantage of a 
blood-stage vaccine would be that even if only partially effective, it would still confer some 
protection, with reduced disease severity, whilst allowing natural immunity to develop [34]. 
Conceptually, therefore, blood-stage malaria vaccines have significant advantages over vaccines 
targeting other life-cycle stages; if pre-erythrocytic vaccines fail to provide sterilising immunity, 
the individual would be vulnerable to severe blood-stage disease and mosquito-stage vaccines 
would offer no protection to the individual once infected. A strong case for malaria vaccine 
development is made by modelling studies which show the substantial benefit that would arise 
from deploying a vaccine that is only partially protective [35, 36]. These models, which typically 
assume a vaccine efficacy of 50%, and a protective half-life of 3 years, predict variable impacts on 
mortality, morbidity and parasite prevalence, depending upon intensity of transmission, 
deployment of other control methods, rate of immune decay and access to healthcare [35-37]. 
They all, however, reach general agreement that even with modest levels of efficacy, a vaccine 
would facilitate reductions in parasite prevalence if used in combination with other strategies. 
This role for a vaccine is very different to the ‘magic bullet’ envisaged in the past; a vaccine 
would form one arm of an integrated programme consisting of indoor residual spraying, long-
lived bed nets, draining of mosquito habitat and provision of artemisinin-based drugs. The effect 
of a hypothetical vaccine with ninety-five percent efficacy and a protective half-life of ten years 
has also been modelled [37], and in this scenario a single mass administration of such a vaccine 
could; eliminate malaria from low-transmission zones; eliminate malaria from moderate-
transmission zones if used in combination with other methods; and reduce prevalence to below 
five percent in high-transmission zones.  
The hypnozoite stage of P. vivax means that individuals who are infected are at risk of relapse of 
disease, and a blood-stage vaccine could, importantly, protect against this (as long as relapses 
occurred within the duration of protective blood-stage immunity provided by vaccination). 
Relapses in vivax malaria occur weeks to months after initial infection, and may arise 10-14 times 
after the primary infection in the absence of eradication therapy, occurring every 3-6 weeks (in 
tropical climates) [5]. 

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Thirdly, the P. vivax Duffy-binding protein (PvDBP) is a very promising antigen for vaccine 
development (see section 3.5). P. vivax requires interaction between the Duffy-binding protein 
and the host Duffy antigen receptor for chemokines (DARC) in order for the parasite to invade 
reticulocytes during blood-stage infection.  Populations who are Duffy antigen negative are 
protected from vivax malaria, as demonstrated by a geographical scarcity of the infections in the 
areas they inhabit (for example, much of sub-Saharan Africa). Furthermore, natural immunity has 
been found to be associated with anti-PvDBP responses [38]. 
3.5 PvDBP as an Antigen 
From the early 1920s until the advent of penicillin in the mid-1940s, induced malaria became the 
standard treatment of neurosyphilis. An observation made soon after the introduction of 
malariotherapy to the United States, was the refractoriness of most people of African origin to 
infection with P.vivax, as opposed to universal susceptibility of persons of other origins [39]. The 
basis for this resistance was not uncovered until the mid-1970s [40] , when it was demonstrated 
that Duffy blood group positivity was required for red blood cell invasion by P. vivax, and nearly 
all West Africans, and a majority of sub-tropical African populations, are Duffy-negative . Twenty 
years later the parasite ligands which interact with the Duffy antigen receptor for chemokines 
(DARC), known as Duffy-binding proteins (DBP), were identified. 
Plasmodium merozoite invasion of erythrocytes is a complex process. The merozoite reorients 
after an initial interaction with the erythrocyte, so that its apical end faces the surface of the cell. 
A tight junction is formed between the merozoite and erythrocyte when the micronemes and 
rhoptries of the merozoite discharge their contents. Plasmodium vivax expresses two 
homologues of the Py235 rhoptry proteins, PvRBP1 and PvRBP2 which bind to reticulocytes and 
not normocytes, presumably explaining the host-cell preference of P. vivax [41]. DBP, which are 
released from the micronemes, are a family of antigens that are functionally conserved across 
Plasmodium species and are thought to be involved in the tight attachment step between the 
parasite and new host cell. The erythrocyte membrane subsequently encases the merozoite, 
creating a vacuole around the invading parasite [38]. 
Unlike P. falciparum which utilises multiple redundant invasion pathways for human erythrocyte 
invasion [41, 42], P. vivax requires interaction with the Duffy antigen receptor for chemokines 
(DARC). Further to population level evidence of the protection of individuals lacking the Duffy 
blood group antigen, as seen across much of sub-Saharan Africa, knockout of the orthologous P. 
knowlesi DBPα gene prevent invasion of Duffy-positive erythrocytes by this highly related 
parasite in vitro [43].  
DBPs have been characterised for both P. knowlesi (PkDBP) [103] and P. vivax (PvDBP) [44]. 
PvDBP has a molecular weight of approximately 140 kDa and a 330-amino acid cysteine-rich 
region within it, known as region II (PvDBP_RII), is predicted to be the domain responsible for 
binding to DARC [45]. It is proposed that PvDBP_RII  dimers bind either one or two DARC 
ectodomains and distinct heterotrimeric and heterotetrameric architectures form on binding [46, 
47]. Structural studies using the highly related P. knowlesi DBPα protein have shown that region 
II of PvDBP is polymorphic, suggesting this region is under immune pressure. However, the 
receptor binding residues within PvDBP_RII  are highly conserved, with polymorphic residues 
clustered at sites that are distal to the DBP binding residues [45]. In-keeping with this, induction 
of binding inhibitory antibodies against these residues does not commonly occur following 
natural exposure [48, 49]. Yet, when these antibodies have been identified, as in a prospective 
cohort study in Papua New Guinea, they have been associated with reduced risk of P. vivax 
infection, lower P. vivax parasite densities and strain-transcending protection [50]. In rabbits, 
antibodies raised against recombinant Salvador I (SalI) strain PvDBP_RII  can inhibit binding of 

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heterologous polymorphic PvDBP_RII  domains derived from diverse field isolates [51].These 
observations suggest that antibodies produced following vaccination with PvDBP_RII  should be 
able to block diverse strains of P. vivax [38].  
Pre-clinically, antibodies blocking PvDBP-DARC interaction have been reproducibly induced by 
immunization using PvDBP_RII –based vaccines in other small animal studies, including in mice 
and rabbits, as well as in non-human primates [46, 47, 52, 53], and those raised against the 
P.knowlesi PkDBPα ortholog can block RBC invasion by this parasite in vitro [45]. Following 
intravenous challenge of New World Aotus monkeys with blood-stage P. vivax, longer pre-patent 
periods and lower parasitaemias were observed in animals immunised with PvDBP-RII in 
comparison to controls. Protection was conferred following immunisation with protein vaccine in 
Freund’s adjuvant but not Montanide ISA 720 (although antibody levels induced by ISA 720 were 
surprisingly low in this study) [54]. 
Over recent years, the critical nature of the PvDBP-DARC interaction with the Duffy antigen 
receptor for merozoite invasion has been challenged, with various reports of P. vivax infection in 
Duffy negative individuals in the literature [55-59]. Currently, the mechanism of invasion of Duffy 
negative erythrocytes is incompletely understood, however, alternative pathways have been 
suggested through identification of novel erythrocyte invasion genes and PvDBP gene duplication 
in clinical isolates by whole genome sequencing[60, 61]. PvDBP gene duplication has not been 
linked to cases of Duffy negative P. vivax infection, however, has been geographically correlated 
with regions also reporting Duffy negative infection, perhaps pointing to involvement of PvDBP, 
even in Duffy negative infection [62]. The further complexities of P. vivax erythrocyte invasion in 
both Duffy positive and negative individuals will continue to be elucidated, and may reveal 
important, potentially synergistic or additive antigenic targets. However, PvDBP-DARC 
interaction likely remains an essential, non-redundant pathway for merozoite invasion in the 
large majority of cases and PvDBP continues to be the current leading target for candidate P. 
vivax blood-stage vaccine development [33, 38], likely with a greater chance of success in 
comparison to the widely tested merozoite antigen targets of P. falciparum. 
3.6 Simian adenoviruses as vectors 
The prevalence of immunity to human adenovirus prompted the consideration of simian 
adenoviruses as vaccine vectors. Simian adenoviruses are not known to cause pathological illness 
in humans and the prevalence of antibodies to chimpanzee origin adenoviruses is less than 5% in 
humans residing in the US [63]. In Equatorial Africa, the natural habitat for chimpanzees, 
prevalence is higher but still below that to anti AdHu5 immunity. In a seroprevalence study in 
Kenya, 23% of children aged 1-6 years had high-titre neutralising antibodies to AdHu5, whilst 
only 4% had high-titre neutralising antibodies to ChAd63. Immunity to both vectors was age-
dependent [64]. Early murine work using chimpanzee adenovirus 68 (ChAd68) expressing gag of 
HIV-1 showed that in comparison to AdHu5 and poxvirus, gag-speciﬁc CD8+ T cell activity was 
superior after immunisation with the ChAd68 construct, with approximately 20% of all splenic 
CD8+ T cells being gag specific.  In the same study, mice pre-exposed to AdHu5 virus failed to 
develop a gag-speciﬁc CD8+ T cell response after vaccination with the AdHu5 vaccine. However, 
the CD8+ T cell response to gag was only slightly decreased in mice pre-exposed to AdHu5 before 
immunisation with the ChAd68 vaccine, suggesting pre-exposure to human adenoviruses should 
not reduce the potency of the immune response generated to simian vectored vaccines [65].  
Simian adenoviruses have been used in clinical trials at the University of Oxford over several 
years. These have included ChAd63 ME-TRAP (a pre-erythrocytic P. falciparum malaria vaccine); 
ChAd63 MSP1 and ChAd63 AMA1 (vaccines against the erythrocytic stage of P. falciparum 
malaria); ChAd63-CS (a second vaccine against the pre-erythrocytic stages of P. falciparum 

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malaria); ChAdPfs25-IMX313 (a vaccine against the transmission stage of P. falciparum malaria); 
in a hepatitis C virus (HCV) vaccine trial by the same group in the form of AdCh3 NSmut and in 
the HIV-1 vaccine candidate ChAdV63.HIVconsv. Importantly, unlike vectors derived from some 
rare human serotypes of adenovirus, the simian vector used in this trial, ChAd63, appears in the 
pre-clinical studies to have similar potency to the human adenovirus serotype 5 (AdHu5) vector. 
3.7 Chimpanzee Adenovirus 63 as a vector (see also IB for ChAd63 PvDBP) 
ChAd63 is a chimpanzee adenovirus. Simian adenoviruses exhibit hexon structures homologous 
to human adenoviruses. Hexons are the major capsid proteins in adenoviruses; they are potently 
immunogenic and the main target of neutralising antibodies. The ChAd63 vaccine vector is 
replication-deficient as the essential E1 gene region has been deleted so the virus can only 
propagate in cells expressing E1 gene products. This means the virus vector cannot replicate in 
human cells within the body. 
ChAd63 expressing various antigens has been administered to over 950 individuals, and has 
demonstrated an excellent safety and tolerability profile. The most widely tested ChAd63 
vectored vaccine is ChAd63 ME-TRAP, which has been assessed in clinical trials since 2007 and 
has been safely administered to adults and children in the UK and a number of African countries. 
Doses up to 2 x 1011 vp have been shown to be safe and there have been no vaccine related SAEs 
to date.   
The vector has been shown to be consistently immunogenic, inducing strong T cell responses and 
moderate antibody responses, especially when combined in a heterologous prime boost regimen 
with MVA. Multiple studies have shown 5 x 1010 vp ChAd63 to be a suitable dose, associated with 
a consistently good reactogenicity profile and strong T cell immunogenicity [66-70] 
It is unlikely that the low level of pre-existing antibodies to ChAd63 in human populations could 
limit widespread use of the vector.  Data from a Phase IIa efficacy study of ChAd63-MVA ME-
TRAP showed no correlation between neutralising antibodies to ChAd63 in volunteers prior to 
vaccination and their subsequent T cell response post MVA boost, suggesting that even if 
neutralising antibodies exist they do not limit immunogenicity [71]. There is also no evidence 
that pre-existing neutralising antibodies to ChAd63 increase reactogenicity [68]. 
3.7 MVA as a Vector (see also IB for MVA PvDBP) 
MVA was originally derived from the vaccinia virus strain Ankara by over 500 serial passages in 
primary chicken embryo fibroblasts (CEF) cells. MVA has six major genomic deletions compared 
to the parental Ankara genome and is severely compromised in its ability to replicate in 
mammalian cells. MVA also shows no cytopathic effect or plaque formation in cells of human 
origin. In irradiated mice, MVA did not elicit any morbidity or lethality even when administered 
at high doses intra-cerebrally, indicating its safety even in immuno-compromised organisms [72].  
MVA has been used as a vaccine and in vaccines for many years. It was used safely in more than 
120,000 previously unvaccinated individuals as part of the smallpox eradication campaign in a 
field study in Germany in the 1970s [72]. The study population included high-risk groups such as 
people suffering from allergies, elderly people and alcoholics. Given intradermally, a red nodule 
of up to 4 mm in diameter was observed at the injection site at day 4 or 5. Only a small 
proportion showed any systemic side effects such as fever > 38.5°C [72]. MVA proved to be non-
contagious and avirulent. Viral replication is blocked late during infection of cells but importantly 
viral and recombinant protein synthesis is unimpaired even during this abortive infection. 
Replication-deficient recombinant MVA has been viewed as an exceptionally safe viral vector. 

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MVA is currently in development as a vector for multiple diseases including HIV-1 [73, 74], 
tuberculosis [75], HCV [76], influenza [77], and melanoma [78]. MVA vectored vaccines are 
particularly suited to boosting immune responses to an antigen following a priming vaccination 
with another viral vector [79]. MVA encoding the pre-erythrocytic P. falciparum target ME-TRAP 
malaria antigens has now been administered to over 1500 individuals, including children and 
infants in sub-Saharan Africa with no serious adverse events to date [66-68, 80-82]. The optimal 
dose of MVA has been shown consistently to be 1-2 x 108 pfu [66-68]([70, 83]. Clinical studies 
have shown intramuscular administration to be associated with fewer and short-lived local AEs 
and no reduction in immunogenicity [68]. 
 
 

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Vaccine candidate 
Development Phase 
Lifecycle stage 
Antigen 
Delivery system 
VMP001 
Phase I/IIa END 
Liver-stage 
PvCSP 
Rec. protein-AS01B 
CSV-S,S 
Pre-clinical 
Liver-stage 
PvCSP 
HBsAg fusion-AS01B 
PvCSP-LSP 
Phase I END 
Liver-stage 
PvCSP 
Synthetic peptides-Montanide ISA 720 
ChAd63-PvTRAP/MVA-PvTRAP 
Pre-clinical 
Liver-stage 
PvTRAP 
Prime-boost, viral vectors 
PvDBPII  
Phase I 
Blood-stage 
PvDBP 
Rec. protein-GLA-SE 
PvDBPII -DEKnull 
Pre-clinical 
Blood-stage 
PvDBP 
Rec. protein 
ChAd63-PvDBPII /MVA-PvDBPII Phase I/IIa 
Blood-stage 
PvDBP 
Prime boost, viral vectors 
PvMSP119 
Pre-clinical 
Blood-stage 
PvMSP1 
Rec. protein-Montanide ISA720 
PvAMA1 
Pre-clinical 
Blood-stage 
PvAMA1
Rec. protein-adjuvant 
Pvs25H 
Phase Ia END 
Transmission-stage 
Pvs25 
Rec. protein-Alhydrogel; Rec. protein-Montanide ISA 51 
Pvs28 
Pre-clinical 
Transmission-stage 
Pvs28 
Rec. protein-adjuvant 
Pvs25-IMX313 
Pre-clinical 
Transmission-stage 
Pvs25 
Rec. protein-adjuvant  
AnAPN1 
Pre-clinical 
Mosquito midgut Ag 
AnAPN1 
Rec. protein-adjuvant 
Table 1: P. vivax vaccine candidates under development: taken from Ref [18]. 
 

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4 ChAd63 PvDBP AND MVA PvDBP VACCINE DEVELOPMENT 
4.1 Characteristics of ChAd63 PvDBP 
ChAd63 PvDBP is a recombinant replication-defective chimpanzee adenovirus expressing the P. 
vivax antigen; PvDBP. PvDBP is a synthetic gene insert encoding the Salvador I allele of the 
conserved, cysteine-rich Region II of the P. vivax Duffy-binding protein.  
4.2 Characteristics of MVA PvDBP 
MVA PvDBP is a recombinant modified vaccinia virus Ankara (MVA) expressing the P. vivax 
antigen; PvDBP. PvDBP is a synthetic gene insert encoding the Salvador I allele of the conserved, 
cysteine-rich Region II of the P. vivax Duffy-binding protein.  
4.3 ChAd63 and MVA encoding PvDBP in pre-clinical studies  
Identical ChAd63 and MVA vectors expressing the Salvador I allele of PvDBP_RII  have been 
shown to be immunogenic in BALB/c mice. Following vaccination with ChAd63 and MVA PvDBP, a 
strong antibody response was seen, with antibodies demonstrating functionality, through 
inhibition of binding of recombinant PvDBP_RII  to the N-terminal of recombinant DARC in vitro. 
The antibodies were also shown to recognise native parasite antigen from P.vivax infected Thai 
patients [53]. A HAdV5/MVA PvDBP viral vectored regime also compared favourably to 
vaccination with recombinant protein PvDBP_RII , administered with the Montanide®ISA 720 
adjuvant, or in a mixed-modality prime-boost regimen (protein-in-adjuvant boost following 
priming with HAdV5-PvDBP), with no significant difference in specific T cell responses, total 
specific IgG titres or binding inhibition, although significantly higher titres and binding inhibition 
were seen in a three-dose protein only regime, administered with the Abisco® adjuvant [53].  
4.4 Clinical experience with ChAd63 PvDBP and MVA PvDBP in a Phase Ia clinical trial (VAC051) 
Safety and immunogenicity of the ChAd63 and MVA viral vectored vaccines targeting PvDBP_RII  
(Salvador I strain) were assessed in the VAC051 (Clinicaltrials.gov identifier: NCT01816113) open-
label dose-escalation Phase Ia study in 24 healthy UK adults in Oxford between 2013-2014 [84]. 
Vaccines were delivered by the intramuscular route in a ChAd63-MVA heterologous prime-boost 
regimen using an 8-week interval. ChAd63 PvDBP was administered to 24 healthy malaria-naïve 
volunteers at doses of 5 x 109 vp (n = 4) and 5 x 1010 vp (n = 20). 8 volunteers received ChAd63 
PvDBP alone, with the first 4 receiving the low dose (5 x 109 vp), before 15 volunteers went on to 
heterologous prime-boost regimens, receiving MVA PvDBP at doses of either 1 x 108 pfu (n= 7) or 
2 x 108 pfu (n=8).  
ChAd63 PvDBP administered alone, and particularly when preceding MVA boost, induced strong 
PvDBP_RII –specific T cell responses, as measured by IFNγ ELISpot. IgG titres were marginal 
following the higher dose prime of ChAd63, but these were boosted to similarly high levels in all 
volunteers by both doses of MVA. PvDBP_RII –specific antibody-secreting cell and memory B cell 
responses were also observed following the MVA boost and the polyclonal immune serum 
inhibited the binding of multiple allelic variants of recombinant PvDBP_RII  to N-terminal DARC. 
Data from this study confirms that the PvDBP antigen is immunogenic and induces strain-
transcending antibodies, which are binding-inhibitory in vitro, when administered as a viral-
vectored vaccine in healthy UK adults.  
ChAd63-PvDBP and MVA-PvDBP were well tolerated and demonstrated a favourable safety 
profile in malaria-naive adults. There were no serious adverse events reported during the 
VAC051 trial, and the majority of vaccine-related adverse events were mild in nature.  

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The most frequently reported adverse event following intramuscular administration of ChAd63 
PvDBP at either of the above doses was injection site pain, seen in the majority of individuals. 
Less frequently, erythema, swelling, warmth and itch were also reported. The overall median 
duration of local adverse events was between 1 and 4 days. The most common vaccine-related 
systemic adverse events were fatigue, headache, nausea, myalgia and arthralgia, with a median 
duration of 1-2 days and being mostly mild in nature.  
MVA PvDBP led to injection site pain in all fifteen volunteers. At a dose of 1 x 108 pfu, pain was 
mild in the majority of individuals but reported to be severe in 1/7 volunteers and 3/8 volunteers 
receiving the higher 2 x 108 pfu. Localised swelling was also seen, which was mild in the majority 
of individuals at both doses. Warmth, erythema and itch were seen less frequently and the 
majority of all local adverse events resolved within 4 days of vaccination. Systemically, the most 
commonly reported AEs were headache and feverishness, which were mild in the majority of 
participants. At the 2 x 108 pfu, there was increased frequency of moderate or severe local and 
systemic adverse events compared to the 1 x 108 pfu dose, however, no systemic adverse event 
was reported to be severe for more than 24 hours. 
4.5 Clinical experience with administering multiple doses of ChAd vectored vaccines 
This trial was temporarily halted because of the COVID-19 pandemic in March 2020, after 
enrolled participants in group 2 received one dose of ChAd63 PvDBP. Their next vaccination will 
be delayed by about 1 year. Because of the long duration of the trial halt, the decision has been 
made to administer a second dose of ChAd63 PvDBP vaccination in these returning volunteers, 
prior to boosting with MVA PvDBP 8 weeks later; instead of giving only a delayed MVA boost. 
A vaccination regime with two doses of a different ChAd vectored vaccine has previously been 
given in a large Oxford Phase I/II randomised controlled COVID-19 vaccine trial where 2 doses of 
ChAdOx1-nCoV19 were administered 4-12 weeks apart to >500 participants, with no safety 
concerns [85]. However since the ChAdOx1 nCov-19 vaccine has been rolled out in vaccination 
programmes worldwide, the vaccine has been associated with rare cases of serious 
thromboembolic disorders with thrombocytopenia following the first dose (see section 8.5.2). 
However, to-date there is no safety signal in the tens of thousands of participants (both in the UK 
and abroad) who have received 2 doses of ChAdOx1 nCov-19 or in those who have received 2 
doses as part of the vaccine rollout. This continues to be closely monitored.  
In a pre-erythrocytic phase Ia malaria vaccine trial in Oxford of the same ChAd63 vector 
backbone, 32 volunteers received two to three doses of ChAd63 ME-TRAP given at varying 
intervals [86]. There were no safety concerns and in fact, adding the second dose of ChAd could 
potentially be advantageous since enhanced CD8+ T cell immunogenicity was reported with the 
addition of an extra priming dose and these cells are of particular interest in Plasmodium vivax. 
There is also an immunological basis for why volunteers in this trial who were primed with 
ChAd63 PvDBP over a year ago now should now receive a second dose. Any immune response 
generated to the first dose will have likely waned such that a booster vaccination with MVA 
PvDBP given 1 year later may well have less of an effect. This assumption comes from a previous 
malaria trial (VAC044) where those receiving an MVA boost 16 weeks after a ChAd prime had a 
trend to reduced responses compared to a shorter interval boost; and this was with a 
heterologous prime-boost regimen (ChAd-MVA) that is known to be more immunogenic than 
homologous ChAd-ChAd prime-boost. So it is likely that responses after heterologous (and 
therefore almost certainly also after homologous) boosting at 1 year will be even further 
reduced. 

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4.6 Concomitant COVID-19 vaccinations 
Trial participants may become eligible for a licensed COVID-19 vaccine during the course of the 
study. The minimum interval between receipt of any malaria vaccines in this trial and any COVID-
19 vaccines has been set to 14 days before to 7 days after receipt of any malaria vaccines 
(compared to 30 days for any other vaccines) and the time window for the MVA PvDBP 
vaccination has been extended to ±14 days to aid scheduling of trial vaccinations around any 
COVID-19 vaccinations if required.  
The antigen of COVID-19 vaccines differ significantly from the malaria antigen tested in this trial 
and none of the currently approved COVID-19 vaccines use the same viral vectors as the malaria 
vaccines being used in this trial. We therefore do not expect a significant impact on 
immunogenicity to the malaria vaccines, if participants receive any COVID-19 vaccines a 
minimum of 14 days either side of any trial vaccinations. 
In regards to safety assessment, assessment of solicited adverse events will not be affected by 
COVID-19 vaccinations if they are given a minimum of 7 days after trial vaccinations. Assessment 
of unsolicited adverse events, in particular delayed events occurring 1 week after any trial 
vaccinations may be more difficult to interpret. However assessment of causality will be based 
on timing and our previous experience with ChAd63 PvDBP and MVA PvDBP in the Phase Ia trial 
(VAC051) conducted in Oxford, as well experience from other trials with the viral vectors ChAd63 
and MVA expressing other disease antigens. 

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5 CONTROLLED HUMAN MALARIA INFECTION  
5.1 
Controlled human malaria infection studies 
5.1.1 Microbial challenge studies of human volunteers 
The deliberate infection of human volunteers with micro-organisms has contributed uniquely to 
our understanding of the pathogenesis, immune responses and the treatment and prevention of 
numerous microbial diseases including P. falciparum malaria, influenza, cholera, typhoid and 
hepatitis [87]. A review by the UK Academy of Medical Sciences on microbial challenge studies 
recognised that such studies are desirable for providing proof of concept for prophylactic and 
therapeutic interventions and can significantly accelerate progress to Phase III studies [87, 88].  
5.1.2 Controlled human malaria infection with Plasmodium falciparum 
P. falciparum CHMI has now become established as a key tool to assess the efficacy of novel 
malaria vaccines and drugs. Following the development of protocols for the continuous culture 
of P. falciparum in 1976 [89] and the generation of mature P. falciparum gametocytes in vitro in 
1981 [90], it became possible to produce laboratory-reared infectious mosquitoes, meaning that 
CHMI trials could be performed more routinely [91]. 
The first well-documented CHMI study with laboratory-reared infectious mosquitoes was carried 
out in 1986 at the US Walter Reed Army Institute of Research (WRAIR), the US Naval Medical 
Research Institute (NMRI) and the US National Institutes of Health (NIH) [92]. The following year, 
the efficacies of the first recombinant protein and synthetic peptide P. falciparum vaccines were 
reported for experimentally infected volunteers [93, 94].  
There are now an increasing number of centres conducting CHMI worldwide, including in Africa, 
and between 1985 and 2009, a total of 1,343 volunteers were experimentally infected with P. 
falciparum [95, 96]. Established methods now include via direct intravenous injection of purified, 
aseptic, cryopreserved sporozoites, as well as blood-stage CHMI, induced by injection of 
cryopreserved parasitised erythrocytes [97]. These models, in addition to mosquito bite 
delivered sporozoite challenge have significantly contributed to the P. falciparum vaccine 
pipeline, including the most clinically advanced candidate RTS,S, which is currently being 
evaluated as part of a WHO pilot programme in Phase IV studies [98]. 
5.1.3  Controlled human malaria infection with Plasmodium vivax  
In comparison to P. falciparum, there is much less experience with P. vivax in the modern CHMI 
era. A key bottleneck has been the inability to culture P. vivax long-term in vitro. Sporozoite 
challenge with P. vivax also carries the risk of relapse weeks to years after infection if 
hypnozoites are not cleared from the liver (there is no dormant liver form in the P. falciparum 
lifecycle). However, there is an extensive history of deliberate infection with P. vivax; most 
notably in malariotherapy, which was carried out for the treatment of neurosyphilis almost a 
century ago. The Austrian psychiatrist Julius Wagner-Jauregg later received a Nobel Prize for his 
work with this treatment [99] and the practice was widely adopted as the only effective 
treatment available at the time. Malariotherapy provided a wealth of information about P. vivax 
infection, which has been reviewed previously [100]. Deliberate infection with P. vivax was also 
conducted in the USA from the 1940s to 1970s in prisoners involved in the Malaria Research 
Project at the Illinois State Penitentiary. The studies mainly examined compounds for their 
potential use as antimalarials, but also assessed the ability to immunise following exposure to P. 
vivax infected irradiated mosquitos, followed by challenge with non-radiated infected Anopheles  
[101, 102]. Similar studies were also carried out at the United States Penitentiary, Atlanta and 

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Maryland USA. Key discoveries of the biology of P. vivax were made during this period, including 
the association between Duffy negativity and resistance to P. vivax infection [40]. These 
experiments demonstrated that CHMI with P. vivax, as well as P. falciparum, could be 
successfully carried out, but the studies were very small.  
5.1.4 P. vivax sporozoite challenge in the modern era 
More recently, over the last few years, a handful of P. vivax challenge studies have been 
reported. The majority of these studies have been mosquito-bite delivered sporozoite challenge 
trials, conducted in Cali, Colombia, the Walter Reed Army Institute of Research (WRAIR), 
Maryland, USA [103] [70] [88] and Oxford (VAC068 study, ClinicalTrials.gov Identifier: 
NCT03377296, unpublished). 
A total of four sporozoite challenge studies have been conducted in Cali. The first trial involved 
eighteen healthy volunteers, exposed to the bites of 2-10 P. vivax infected Anopheles albimanus 
mosquitoes, of which seventeen developed infection. Authors speculated that the volunteer who 
did not develop malaria had surreptitiously taken anti-malarial medication but this was never 
confirmed [103]. There were no serious adverse events (SAEs) in this trial, but seven volunteers 
required fluid therapy due to nausea and vomiting, and five developed blurred vision lasting 2-3 
days after treatment initiation with chloroquine. The second P. vivax CHMI trial was carried out 
by the same group in Colombia, aiming to demonstrate the reproducibility of this method of 
infection using three different A. albimanus mosquito lots fed on blood from three P. vivax-
infected donors [104]. Seventeen individuals whose red blood cells were positive for the Duffy 
antigen/chemokine receptor (DARC, “Duffy positive”) and five Duffy negative controls were 
enrolled then randomly assigned to three groups (with six Duffy positive individuals in two of the 
groups and five in the third group). Following 2-4 bites from infected mosquitoes, all Duffy 
positive participants (and none of the Duffy negative participants) developed blood-stage 
malaria. A third P. vivax CHMI trial was carried out in Cali among both ‘semi-immune’ 
(previously-exposed; n=9) and malaria-naïve adult volunteers (n=7) [105]. Symptoms were 
significantly worse among the malaria-naïve subjects but there were no SAEs.  
The most recent CHMI trial from the Cali group assessed “immunisation” through repeated 
exposure to radiation-attenuated sporozoites, delivered by mosquito bite. Moderate efficacy was 
demonstrated in 42% of volunteers, who were sterilely protected following sporozoite challenge 
(five out of twelve Duffy positive participants protected). There were no reported SAEs related to 
immunisation, although one volunteer developed severe elevation of hepatic transaminases (>10 
times the upper limit of normal [x ULN]) with associated abdominal pain and vomiting following 
CHMI, with no alternative cause found. These symptoms resolved spontaneously [27]. 
The first P. vivax sporozoite challenge in Europe was recently conducted in April 2018, in Oxford 
within the VAC068 study (ClinicalTrials.gov Identifier: NCT03377296). Two malaria-naïve adult 
volunteers were exposed to five infectious bites (bites by mosquitos with >10 sporozoites as 
detected on microscopic examination of salivary glands post-feeding) by Anopheles dirus 
mosquitoes. Infection in the mosquitoes was established by direct membrane feeding on the 
blood from a P. vivax infected source patient, in Songkhla, Southern Thailand, before transport of 
the infected mosquitoes to the UK. Both volunteers were successfully infected, with parasitic 
DNA being detectable from day 9 after challenge by qPCR in both subjects. Symptoms consistent 
with malaria infection, including fatigue and subjective feverishness, chills, headache, loss of 
appetite, nausea and malaise, were reported by one volunteer from day 11 after challenge and 
on day 14 by the second volunteer. Fever was detected in both subjects on day 14. Thick film 
microscopy was positive (≥2 morphologically normal asexual parasites seen in 200 high-power 
(1000x) fields) in the asymptomatic volunteer on the evening of day 13 and at day 14 in the more 

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symptomatic volunteer, leading to diagnosis on day 14 in both volunteers. A 250mL blood 
donation was made by each volunteer, immediately prior to initiation of anti-malarial treatment, 
without complication, for cryopreservation and future use as a parasitised blood inoculum for 
blood-stage challenge. After 48 hours’ anti-malarial treatment, both thick film microscopy and 
qPCR were negative (two consecutive substantially reduced results) and both volunteers 
completed the clinical follow-up period, including a two-week course of primaquine for radical 
cure of hypnozoites, until 90 days post-challenge, without safety concerns. To-date (more than 8 
months post completion of primaquine therapy) there has been no report of symptoms to 
suggest relapse in either volunteer (email questionnaire follow-up is being continued for 5 years). 
5.1.4 P. vivax challenge for assessment of vaccine efficacy  
In only two of the P. vivax CHMI studies conducted to date has efficacy of immunisation been 
assessed, with both candidate vaccines targeting the pre-erythrocytic stage and utilising the 
mosquito-bite delivered sporozoite challenge model (Table 2 – taken from Payne et al., Trends in 
Parasitology, 2017 [106]). Only one of these studies has been published to date; the 
VMP001/AS01B vaccine was tested in healthy malaria-naïve adults at the WRAIR in the USA 
[107]. VMP001 is a soluble recombinant protein vaccine [108], encoding the P. vivax 
circumsporozoite protein (PvCSP) administered with the AS01B adjuvant (GlaxoSmithKline). The 
vaccine was administered to 30 volunteers in three cohorts (10 in each) at doses of 15 µg, 30 µg 
and 60 µg, given three times at a 4 week interval between the first and second dose; the third 
dose was given 8 (15 µg cohort), 6 (30 µg cohort) or 4 (60 µg cohort) weeks after the second. 
Twenty-nine volunteers completed the vaccination phase, with twenty-seven proceeding to 
sporozoite CHMI, delivered by mosquito bite, two weeks after final vaccination, alongside 6 
malaria-naïve controls. Vaccine protective efficacy was 0%; all volunteers had developed thick 
blood film-detectable parasitaemia by day 13. The median pre-patent period for all immunised 
participants was 11.9 days versus 10.7 days for infectivity controls. The challenge was well 
tolerated with no untoward reactogenicity following mosquito bites and no untoward SAEs in 
challenge and treatment phases. Participants were treated with standard chloroquine and 
primaquine therapy with rapid clearance of infection. However, two volunteers went on to have 
multiple relapses. One participant experienced two relapses (at weeks 8 and 18 after CHMI), 
while the other experienced three (at weeks 11, 20 and 48 after CHMI) [9]. By study completion 
the participants had been followed up for 5 years, and had not had any further relapses [107]. 
Exploratory genotyping for the cytochrome P450 (CYP) allele CYP2D6 was undertaken in 25 of 
the 33 volunteers. The volunteers with relapses were found to have either an intermediate-
metaboliser phenotype or poor-metaboliser phenotype. These phenotypes were associated with 
significantly lower levels of primaquine clearance 24 hours after dosing [9]. Results from another 
P. vivax CSP vaccine candidate, CS long synthetic peptides formulated in Montanide ISA 51, 
assessed in a mosquito-bite challenge study are currently awaited (Clinicaltrials.go identifier 
NCT02083068). 
No recombinant viral-vectored P. vivax vaccine candidate has previously been assessed in a CHMI 
study. ChAd63 and MVA are known potent inducers of T-cell responses. Data from the Phase Ia 
assessing the safety and immunogenicity of ChAd63 and MVA PvDBP demonstrated that ChAd63 
PvDBP, both when administered alone, and particularly when boosted by MVA PvDBP, induces 
strong PvDBP_RII –specific T cell responses, as measured by IFNγ ELISpot, thereby inducing high 
levels of effector T-cells to a blood-stage antigen [84]. In the Plasmodium berghei mouse model, 
adoptive transfer of T-cells primed to blood-stage antigens can induce immunopathology [109, 
110]. This was not, however, observed in further murine studies, where viral-vectored vaccine 
induced strong cellular responses were instead found to be protective [111, 112]. Additionally, 
no concerns regarding immunopathological phenomena have ever been identified in human 

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Page 35 of 128 
clinical trials assessing P. falciparum blood-stage viral vectored vaccines in challenge studies. 
However, given this small potential for risk, in the first CHMI efficacy trial assessing the P. 
falciparum blood-stage candidate vaccines ChAd63 and MVA AMA1 against a blood-stage 
challenge (VAC037), a cautious approach was implemented, with a small pilot study taking place 
before efficacy assessment in a larger cohort. Initially, three volunteers were vaccinated and 
went on to receive a blood stage challenge before a larger group of 38 volunteers were enrolled 
in a second, follow-on study (VAC039) assessing the viral-vectored AMA1, MSP1 and ME-TRAP 
vaccine candidates, with no safety concerns identified in either trial [83]. For safety reasons, the 
same model for assessment of safety of CHMI following vaccination will be adopted in the 
VAC071 study. 

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Trial Site 
Number of volunteers 
Pre-patent period 
(days)a 
Number of infected 
mosquitoes OR inoculum 
Number of volunteers with 
patent parasitaemia 
References 
Sporozoite (mosquito-bite) CHMI studies 
 
Cali, Columbia 
18 
9 – 13 
2 - 10 
17/18 
[103] 
Cali, Columbia 
17 Duffy positive 
5 Duffy negative 
9 – 16 
2 - 4 
17/17 (Duffy positive) 
0/5 (Duffy negative) 
[104] 
Cali, Columbia 
7 malaria-naïve 
9 semi-immune 
11 – 13 
2 - 4 
16/16 
[105] 
WRAIR, USA 
27 vaccinees  
6 infectivity controls 
10 – 13 
10 – 11 
5 
 
[107] 
Cali, Columbia 
12 Duffy positive vaccinees 
2 Duffy positive controls 
5 Duffy negative controls 
12 – 13 
2 - 4 
7/12 vaccinees 
2/2 Duffy positive controls 
0/5 Duffy negative controls 
[27] 
Blood-stage CHMI studies  
 
QIMRB, Australia 
2 
8-9 
13,000 genome equivalents 
2/2 
[113] 
QIMRB, 
Australia 
6 
8-9 
31,786 (± 11,947) genome 
equivalents (= 15 ± 5 viable 
P. vivax parasites) 
6/6 
[114] 
Table 2: Overview of Published Plasmodium vivax CHMI Studies. aThe pre-patent period refers to the period before malaria diagnosis: by blood film 
(sporozoite) or qPCR (blood-stage).

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5.1.5 Modern blood-stage controlled human P. vivax infection 
To date, there have been four studies of blood-stage P. vivax CHMI, of which two are published, 
all conducted at the Queensland Institute of Medical Research (QIMR), Brisbane Australia. Both 
published studies used a cryopreserved source of parasitised erythrocytes obtained from a 
returned traveller with blood group A, Rhesus negative, who was infected with P. vivax during a 
trip to the Solomon Islands [113, 114]. The first blood-stage P. vivax CHMI in Europe took place in 
January 2019, in Oxford (VAC069) – see section 5.2.7 for a full description.  
In the first blood-stage CHMI at QIMR, Brisbane, two volunteers were inoculated with 270µL of 
reconstituted parasitised red cells, containing approximately 13,000 genome equivalents. Both 
subjects were successfully infected, with PCR becoming positive on day 8 or 9. Clinical symptoms 
consistent with malaria infection were present from day 11 in one volunteer, who reported 
myalgia, headache and malaise and day 14 in the other, with both experiencing chills and sweats 
at day 14. Treatment with artemether/lumefantrine was started at day 14 and volunteers were 
admitted for ongoing monitoring. Both volunteers experienced worsening of symptoms over the 
initial 12 hours post-treatment, including nausea and vomiting, headache, sweats and rigors in 
one volunteer. Pyrexia above 39oC was detected in both volunteers. After 24 hours of anti-
malarials, all symptoms had resolved, although non-tender clinically palpable mild splenomegaly 
was detected in one subject at day 15. By day 28, splenomegaly had resolved fully and no other 
adverse events were reported by either subject in the period since discharge. Whole genome 
sequencing was performed, demonstrating a genetic sequence most closely related to Cambodia 
strains, of the publically available strains. Gametocytaemia was measured by quantitative 
reverse-transcriptase PCR for the pvs25 transcript, a mature gametocyte marker. Pvs25 
transcripts were detectable from day 11 or 12 and peaked at day 14 in both volunteers, 
coinciding with peak quantitative parasite PCR, prior to the initiation of anti-malarial treatment 
[113].  
A second study was conducted to demonstrate reproducibility of the blood-stage controlled 
infection method and assess transmissibility of infection to Anopheles stephensi mosquitoes. Six 
volunteers were infected after receiving an inoculum containing approximately 31,786 (+/- 
11947) genome equivalents, estimated by investigators using linear regression growth modelling 
to equate to 15+/-5 viable parasites. Evolution of clinical symptoms was similar to the first study, 
with volunteers developing symptoms in keeping with malaria infection on days 11-13 (mean 
12.2). There were no serious adverse events during the course of either study, but for 4 of 6 
volunteers, liver enzymes became significantly elevated, above 5 times the upper limit of normal. 
Mild bilirubinaemia was also detected in three subjects, however, increases were transient and 
did not exceed 2 times the upper limit of normal. No clinical manifestations were associated with 
biochemical abnormalities. No other cause for this deranged liver function was found and liver 
ultrasound was normal but abnormalities subsequently resolved spontaneously without 
sequelae [114]. Transmissibility of infection was assessed by both direct feeding assay (DFA) and 
membrane feeding assay (MFA), carried out 3 days prior to the anticipated peak parasitaemia 
and initiation of treatment on day 14, as predicted from the first study. A total of 16 DFAs and 32 
MFAs were performed, with rates of successful feeding above 90% across the two methods, 
without significant difference between the two. Overall, 1801 mosquitoes were dissected for 
examination of oocysts 7-9 days after feeding, of which 1.8% (n=32) were demonstrated to be 
infected, although the rate of infectivity was five times higher for DFA when compared to MFA. 
Other atypical ovoid structures were also detected by investigators on the mosquito midgut, 
which could not be identified by PCR as either microsporidia or fungal pathogens, known to 
infect mosquitoes. For standardisation of the method, if used for drug or vaccine efficacy 

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evaluation, other methods for confirmation of oocysts will be required. The reason for low 
infectivity could not be determined, however, a possible incompatibility of the Solomon Island 
derived parasite strain and the laboratory-reared A. stephensi colony, which had originally been 
sourced from India, was cited by the authors as a potential contributory factor. While small, 
these studies demonstrate the safety, feasibility and reproducibility of a P. vivax blood-stage 
challenge model and show the potential for use as a transmission model for evaluation of 
transmission-blocking vaccine candidates, although the methodology is yet to be optimised.  
5.1.6 Rationale for blood-stage controlled human malaria infection 
Mosquito-bite CHMI most closely models natural infection and the robustness and reproducibility 
of the P. vivax mosquito-bite delivered sporozoite challenge model has recently been 
demonstrated by Herrera et al. in South America [103, 104]. More recently, the safety and 
feasibility of a sporozoite P. vivax challenge, was demonstrated for the first time in Europe in April 
2018 within the ongoing VAC068 study in Oxford (ClinicalTrials.gov Identifier: NCT03377296). Since 
cryopreserved P. vivax sporozoites are yet to be developed for human trials, mosquito-bite 
delivered CHMI will remain the mainstay for CHMI in assessment of pre-erythrocytic vaccines and 
drugs. However, for vaccines and anti-malarials targeting the erythrocytic stage, the blood-stage 
offers a number of advantages over sporozoite CHMI.  
Infection of mosquitoes requires a ready supply of blood containing gametocytes, from an infected 
patient. Without the possibility of long-term P. vivax ex-vivo culture, supply is limited to endemic 
areas. For CHMI studies conducted in non-endemic zones, this necessitates infection and 
importation of mosquitos from an appropriate area, with suitable entomological facilities and 
expertise, which may be logistically demanding, particularly in cases of vaccine efficacy studies, 
where timing of challenge may be critical.  
Blood stage CHMI also permits both better characterization and standardization of the parasite 
inoculum. Parasite density of the cryopreserved isolates can be established, increasing 
homogeneity of initial parasite inoculum density, when compared to sporozoites delivered by 
mosquito bite, and allowing the possibility of controlled variations of the administered parasite 
load. Full genome sequencing, including screening for mutations known to be associated with drug 
resistance can also be performed prior to challenge. In addition, safety data can be accrued 
through multiple uses of the same inoculum. Together, standardisation of strain and density 
permit for better comparison between candidate vaccines, when evaluated through challenge 
using the same inoculum source.  
Since parasitic load introduced via intravenous injection is smaller than that released following 
schizogony at the liver-stage, as in natural infection and sporozoite challenge, there is a longer 
period of blood-stage multiplication. This provides an extended period for assessment of parasite 
multiplication rate (PMR), before the development of clinical symptoms or diagnostic criteria 
might be reached. In addition, comparison of PMR between infectivity controls from blood-stage 
CHMI performed in Oxford within the VAC054 trial, assessing efficacy of the P. falciparum apical 
membrane antigen 1 (AMA1) vaccine candidate, FMP2.1/AS01, and historic controls challenged by 
mosquito-bite, illustrated that although mean PMR was comparable, blood-stage challenge 
produced a much narrower range of PMR (smaller standard deviation with tight 95% confidence 
intervals). This provided greater power to detect partial vaccine efficacy, making blood-stage 
challenge a more robust tool for evaluation of candidate blood-stage vaccines [115]. This was 
indeed borne out in the recent Phase IIa efficacy study of the candidate vaccine RH5.1/AS01B, 
where the blood-stage challenge model was able to reliably detect a 17% reduction in the PMR 
between vaccinees and infectivity controls, with a high degree of confidence (P<0.02) (VAC063, 
ClinicalTrials.gov Identifier: NCT02927145). 

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Significantly, in addition to advantages seen with P. falciparum blood-stage CHMI, P. vivax blood-
stage challenge provides a mode of infection which by-passes the liver stage. This eliminates the 
possibility of hypnozoite formation and therefore, risk of relapse. Equally, there is no requirement 
for CYP2D6 phenotype screening and primaquine therapy. A P. vivax blood-stage challenge is 
therefore less restrictive and confers important safety benefits over sporozoite challenge.  
5.2 Cryopreserved Plasmodium vivax blood inoculum 
5.2.1 Source and preparation of the cryopreserved inoculum 
The cryopreserved parasitized red blood cells that will be used were produced by Dr Angela 
Minassian, Prof Simon Draper and colleagues at the University of Oxford in April 2018, as part of 
the VAC068 study (ClinicalTrials.gov Identifier: NCT03377296), approved by the South Central - 
Oxford A Research Ethics Committee.  
5.2.2 Collection of P. vivax infected erythrocytes  
Parasitised erythrocytes were collected from two P. vivax-infected volunteers (otherwise 
healthy), who donated blood following sporozoite P. vivax CHMI, delivered by mosquito bite. 
Volunteers were infected via five infectious bites (defined as bites by mosquitoes with >10 
sporozoites as detected on microscopic examination of salivary glands post-feeding) from 
infected laboratory-reared Anopheles dirus mosquitos, under controlled conditions. Infected 
mosquitos were provided by, and imported from, The Mahidol University, Bangkok. The colony is 
maintained through feeding on rigorously screened human blood (provided by the Red Cross) to 
induce egg-stimulation, animal blood is never used. For infection of mosquitos, a source patient 
was recruited from a medical clinic in one of Thailand’s Southern endemic areas – Songkhala (~7 
hours’ drive from the Vivax Research Unit in Bangkok). Microscopic diagnosis of the source 
patient was established at both the field site and in the Bangkok reference laboratory, where PCR 
analysis confirmed P. vivax mono-infection. Molecular speciation by PCR (research-grade 
laboratory assay) was verified at the Jenner Institute Laboratories and clonality of the infection 
was established by the Wellcome Trust Sanger Institute in Cambridge, UK, on a 2mL whole blood 
sample, sent directly by courier from Thailand to Oxford. Mosquitoes were infected via direct 
membrane feeding with blood from the source patient, and infectivity was confirmed at 5-7 days 
post-feeding through oocyst count on dissection of the midgut. 
Both UK volunteers (“Donors”) were followed from days 1-6 post-challenge by telephone and 
from the evening of day 6 at twice-daily clinic visits. Blood sampling was performed at each visit 
for thick film microscopy and PCR. Clinical symptoms consistent with malarial infection were 
reported from day 11.5 post-challenge in Donor 1 and from day 14 in Donor 2, with both 
becoming febrile at day 14. Thick film positivity was defined as the detection of at least two 
morphologically normal malaria parasites seen in 200 high-power (1000x) fields. Thick film 
microscopy was positive at day 14.5 in volunteer 1 and at day 13.5 in volunteer 2, corresponding 
to 31,010 and 16,717 genome copies/mL by PCR, respectively. Blood donation was performed in 
each volunteer immediately prior to initiation of treatment on the morning or afternoon of day 
14. A 250mL blood sample was collected using aseptic technique, via a whole blood donation kit 
(Leuokotrap WB, Haemonetics Corp), containing an in-line leukodepletion filter. For 
anonymization of the blood donor, blood collected for cryopreservation was labelled with either 
“Donor 1” or “Donor 2”. Traceability of the blood donor is however maintained within a 
confidential clinical record, which may be accessed by the Chief Investigator, or by key members 
of the clinical team, to whom responsibility is delegated, if requested by the sponsor or other 
external bodies. After blood collection, treatment with artemether/lumefantrine (Riamet®) was 
administered, followed by a two week course of primaquine. No supportive treatment or 

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admission was required. Follow-up (clinic visits) until 90 days post-challenge was completed, with 
no safety concerns. Ongoing follow-up by email will continue for 5 years in order to monitor for 
relapse. 
5.2.3 Cryopreservation and storage of blood bank 
After collection, blood was maintained at 37oC and transported immediately to the Jenner 
Institute Laboratory, University of Oxford. All laboratory processing was conducted under GMP-
like conditions, under QP and QA oversight. Procedures were performed within fumigated 
microbiological safety cabinets, under precautions in compliance with Containment Level 3 Code 
of Practice and with sterile technique.  
First, the red cells were separated from plasma by centrifugation of the leukodepleted blood 
before mixing with Glycerolyte 57 (at 1:2 erythrocyte to Glycerolyte 57 volume ratio). The first 
20% of Glycerolyte 57 was added dropwise with gentle agitation, the suspension was then 
incubated for 5 minutes at room temperature before the remaining Glycerolyte 57 was added. 
The RBC-Glycerolyte mixture was aliquoted into 1.5mL cryovials and frozen at -80oC for one night 
before transfer to a dedicated liquid nitrogen tank. After 6 days, samples were transferred to 
Thermo Fisher Bishop’s Stortford temperature-monitored liquid nitrogen facility, Hertfordshire, 
UK, where samples are stored on behalf of the University of Oxford. This process was performed 
under conditions similar to those used for blood thawing in previous CHMI trials at Oxford and 
according to the Jenner Institute Laboratory SOPs. 
5.2.4 Infectivity and characterisation of parasite stock 
Confirmation of parasitic density within the blood collected for cryopreservation was performed 
via microscopy and quantitative PCR on the leukodepleted blood samples. Thick film microscopy 
demonstrated 11 asexual parasites per 1µL leukodepleted blood for Donor 1, and 5 asexual 
parasites per 1µL leukodepleted blood for Donor 2. Quantitative PCR confirmed the presence of 
23,566 genome copies/mL in Donor 1, and 14,078 genome copies/mL in Donor 2. This suggested 
minimal parasitic loss through the leukodepletion process when compared to the diagnostic PCR 
values of 31,010 and 16,717 genome copies/mL, respectively. 
Viability has also been demonstrated in an ex-vivo short-term culture of thawed infected red 
blood cells in enriched McCoy 5A medium. Parasitic growth was detectable by light microscopy, 
quantitative PCR and flow cytometry through an initial 40-hour growth cycle in samples collected 
from Donor 1, with normal progression of normal morphology as seen on Giemsa stained thick 
and thin films. However, parasite growth was sub-microscopic in samples obtained from Donor 
2. Therefore, we intend to proceed with further testing of cryopreserved samples from Donor 1, 
and will use this as the challenge inoculum in this and future studies. Further testing will include 
whole genome sequencing to further characterize the parasitic strain, with particular scrutiny for 
SNVs present in the five putative drug resistant genes pvdhfr, pvdhps, pvcrt, pvmdr and pvmrp.  
5.2.5 Testing of source patient and blood donors for blood-borne and mosquito-borne 
infections 
Initial testing for blood-borne infections and mosquito-borne disease was carried out on blood 
samples from the original source patient in Thailand, taken at the time of P. vivax diagnosis. 
Since Anopheles is a known vector of Wucherichia bancrofti, the main causative agent of 
lymphatic filariasis, blood was screened for filarial disease via rapid diagnostic test for IgG4 
antibodies to the W. bancrofti Wb123 antigen (SD BIOLINE Lymphatic Filariasis IgG4) at the Thai 
field site. In addition, although there is no evidence that blood-borne infections can be 
transmitted by mosquito bite, for maximal assurance of safety, serology for HIV-1 and HIV-2, 

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HTLV, Hepatitis B and C and syphilis were performed on a serum sample from the Thai source 
patient, at Oxford University Hospitals NHS Trust. Due to anecdotal reports of Japanese B 
encephalitis and Chikungunya in Anopheles species, blood from the source patient was also 
screened for both arboviral infections by PCR, as performed by the WRAIR unit, who used the 
same mosquito source for a CHMI trial that assessed the efficacy of the VMP001/AS01 P. vivax 
circumsporozoite recombinant protein vaccine[107]. As a further precautionary measure, 
although Anopheles species are not known to be vectors of Dengue, Zika or West Nile virus, on 
the independent advice of clinical Tropical Medicine specialist, Prof. Nicholas Day, Professor of 
Tropical Medicine and Director of the Mahidol Oxford Tropical Medicine Research Unit in 
Thailand, PCR for these infections was performed on the source patient’s blood. In summary, 
molecular analysis (PCR) for Chikungunya, Japanese B encephalitis, West Nile, Dengue and Zika 
viruses was performed on whole blood at the Rare Imported Pathogens Laboratory (RIPL) in the 
UK. All source patient infection screen tests were negative.  
Both UK volunteers (“donors”) were subjected to screening for blood-borne infections, in line 
with the Joint UK Blood Transfusion and Tissue Transplantation Services Professional Advisory 
Committee guidelines https://www.transfusionguidelines.org/red-book/chapter-9-microbiology-
tests-for-donors-and-donations-general-specifications-for-laboratory-test-procedures/9-1-
general-requirements. Testing comprised serological tests for HIV-1 and HIV-2, hepatitis B and C, 
syphilis (anti-treponemal Ab) and HTLV-1 and HTLV-2 at screening, and nucleic acid amplification 
tests for HIV-1 and hepatitis B and C, as well as repeat serological tests for HTLV-1 and HTLV-2 
and syphilis 7 days before sporozoite challenge. Neither volunteer had travelled to any area 
which represented a risk of exposure to any other form of blood-borne infection. All tests were 
negative. Volunteers also underwent repeat serological testing for HIV, hepatitis B and C, syphilis, 
HITLV-1 and HTLV-2, 90 days after challenge was undertaken, to ensure that no seroconversion 
from a recently-acquired infection (that may have been undetectable around the time of 
challenge) had occurred since the challenge period. All tests remained negative.  
In addition, volunteers were screened for Epstein-Barr virus (EBV) and Cytomegalovirus (CMV) 
prior to enrolment. Both volunteers were IgG seropositive for both infections. However, 
leukodepletion has been shown to be effective in preventing transmission of both EBV and CMV 
[116] and PCR testing for both infections on the inoculum was negative, therefore, EBV-CMV 
concordant serostatus would not be considered a requirement for recipients of this donated 
blood in this study. This is in line with conduct of previous P. falciparum CHMI studies at Oxford, 
which have utilised a cryopreserved source of infected erythrocytes from a donor who was 
seropositive for both EBV and CMV. Initial studies using this inoculum had initially required that 
participants in CHMI trials be seropositive for both infections. However, following the 
development of PCR assays for both infections, molecular analysis of the inoculum was negative 
for both EBV and CMV. Following a risk-assessment, QIMR, Australia, subsequently removed 
seropositivity to these viruses as a criterion for participation as a recipient of the inoculum. In a 
previous P. falciparum challenge study (VAC054) at Oxford, 63% of volunteers were seronegative 
for CMV and 11% were seronegative for EBV pre-CHMI, and no cases of seroconversion were 
recorded post-CHMI [115]. Volunteers will however be informed of the theoretical risk of 
transmission of infection and this will be included within the consent form. Serostatus will be 
tested prior to CHMI at screening for volunteers as part of this protocol and will be re-tested 
post-challenge. Serum samples post-CHMI will also be stored, for serostatus analysis of any 
infection, should this be required or requested by the Chief Investigator.  

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5.2.6 Sterility and screening for blood-borne infections of cryopreserved blood bank 
Blood collected for cryopreservation was tested for bacterial contamination using validated GMP 
and GLP laboratory techniques. These included tests of sterility by direct inoculation, 
mycoplasma specific culture and detection and quantification of bacterial endotoxin by kinetic 
chromogenic limulus amoebocyte lysate assay (see Non-investigational Medicinal Product 
Dossier for PvW1). All of these assays were performed by SGS Vitriology, Glasgow, UK, using 
assays compliant with harmonised European Pharmacopeia and United States Pharmacopeia 
standards.   
A further screen for blood-borne infections was conducted on the plasma, derived directly from 
the blood bank (separated from the red cells prior to freezing down), in line with testing 
procedures performed by the NHS Blood Transfusion service. DNA PCR for HIV-1, hepatitis B, 
hepatitis C, EBV, CMV, serology for HIV-2 and serology for HTLV-1, HTLV-2, and Treponema 
pallidum (RPR) was performed on thawed plasma samples at University Hospitals Birmingham 
NHS Foundation Trust laboratory. All tests were negative.  
5.2.7 Determination of safety, feasibility and dose of cryopreserved P. vivax inoculum  
Safety and feasibility of blood-stage P. vivax challenge, using the same bank of cryopreserved P. 
vivax infected erythrocytes as will be used in this trial, was assessed for the first time by CHMI in 
the VAC069 study in January 2019 (ClinicalTrials.gov identifier: NCT03797989). This proof-of-
concept assessed feasibility of infection at three different doses of inoculum, by injection at 
three dilutions, with a view to identifying the lowest concentration producing a reliable infection 
within a practicable timeframe.  
Six healthy, malaria-naïve adults aged between 18 and 50 years were recruited into three groups, 
each comprising two volunteers. Two volunteers receive a whole vial’s worth of infected 
erythrocytes, two volunteers received one fifth of the dose of parasitised erythrocytes, at a 1:5 
dilution, and the final two volunteers were inoculated with one twentieth of the dose, at a 1:20 
dilution. Intravenous inoculation of volunteers was completed without complication, with all 
volunteers safely discharged at 1 hour post-CHMI following satisfactory observation. The overall 
safety profile was in-keeping with AEs as expected in P. vivax CHMI, and comparable to AEs as 
reported in previous P. vivax blood-stage challenge studies, as summarised below [113, 114].  
Safety data was actively collected (solicited adverse events) on the following symptoms deemed 
indicative of P. vivax infection at post-challenge clinic visits until 28 days after CHMI: subjective 
feverishness, chills, rigors, sweats, headache, nausea, vomiting, diarrhoea, myalgia, arthralgia, 
lower back pain, fatigue and general malaise. Clinic visits were once or twice daily from day of 
challenge until completion of anti-malarial therapy, depending on the number of days since 
challenge and qPCR result, followed by assessment at 6 days post treatment initiation and 28 
days post-CHMI, as set out by the study protocol. The severity of adverse events were self-
assessed by volunteers who were counselled on criteria for grading as set out in Table 13. 
Unsolicted AEs and SAEs were assessed throughout the study period. 
Prior to, or at the time of malaria diagnosis, the majority of volunteers (4/6) experienced either 
no or mild AEs, whilst 2/6 volunteers reported a constellation of moderate to severe AEs 
including feverishness, chills, sweats, headache, fatigue and malaise (Figure 3). AEs reported as 
moderate or severe in intensity were more frequent post-diagnosis, following initiation of anti-
malarial therapy and were reported by 5/6 volunteers, each experiencing 1-6 AEs graded as 
severe in intensity. However, no AE reported as severe persisted at grade 3 for more than 48 
hours, with the vast majority resolving completely within 24 hours (Table 3). The most frequent 
AEs reported as moderate-severe (grade 2-3) in intensity were feverishness, chills, malaise, 

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Page 43 of 128 
fatigue and sweats (Figure 2). The large majority of all AEs resolved within 72 hours of anti-
malarial treatment, with only a single volunteer reporting any solicited AE in the period between 
two and six days after treatment of mild-moderate intensity, which completely resolved at 28 
days after challenge.  
AEs relating to physical observations were mostly mild in nature, with a single grade 3 pyrexia 
occurring (graded as per local SOP), which resolved within 24 hours (Figure 4). Of the laboratory 
AEs recorded, two were grade 3 in severity (graded as per local SOP), both relating to 
lymphocytopaenia in two volunteers at the time of diagnosis (Tables 4 and 5). These grade 3 
events were transient, resolving completely within 6 days, and the abnormality was deemed to 
be in keeping with P. vivax malaria diagnosis. Given reported transaminitis in previous P. vivax 
CHMI studies, liver function tests were monitored through the post-CHMI period on days 7 and 
14 post-challenge, on day of diagnosis, days 1 and 6 following treatment commencement and 28 
days after challenge. Moderate (grade 2) transient derangement of ALT on liver function tests 
was seen in only 2/6 volunteers, detected at 6 days post-treatment. Both volunteers were 
asymptomatic and transaminases normalised by 28 days post-CHMI (within 10 days).  
To supplement clinical assessment following initiation of anti-malarial therapy and confirm 
parasitological clearance, qPCR was performed on days 1 and 2 post-treatment. There was a 
substantial reduction in parasite genome copies/mL by qPCR in all volunteers within 48 hours of 
therapy (5/6 treated with artemether/lumefantrine (Riamet), 1/6 treated with 
atavoquone/proguanil (Malarone)) and qPCR remained negative at 6 days post-treatment 
initiation in all volunteers. AEs relating to treatment were infrequently reported, and were mild-
moderate in nature where experienced (Figure 5). No grade 3 unsolicted AE was reported and 
there have been no SAEs to date in the VAC069 study. 
Feasibility of CHMI through intravenous administration of the P. vivax inoculum was 
demonstrated by the successful infection of all volunteers, with a mean day of diagnosis of 15 
days after CHMI (range 12.5-16.5). The two volunteers receiving the highest inoculum dose were 
diagnosed at days 12.5 and 15.5 respectively, those receiving a 1:5 dilution were both diagnosed 
at day 15 and those receiving the 1:20 dilution were diagnosed at days 15.5 and 16.5. All three 
dilutions were therefore demonstrated to be reliably infective. Based on these infectivity data, 
and accounting for possible variation in number of parasitised erythrocytes between thawed 
cryopreserved vials, an inoculum dilution of 1:10 (prepared as per Jenner laboratory SOP) will be 
utilised for P. vivax blood-stage CHMI in this VAC071 study.  
.Volunteers are scheduled to return to undergo a second challenge in September 2019 
(approximately) and third challenge in February 2020 (approximately) to establish safety and 
feasibility of secondary and tertiary P. vivax controlled blood-stage challenge. The final follow-up 
will be 90 days after the tertiary challenge, approximately 1 and half years from enrolment. The 
natural immune response to primary, secondary and tertiary challenge, as well as 
gametocytaemia will also be explored following primary, secondary and tertiary blood-stage P. 
vivax infection. PCR quantification of gametocytes following primary challenge, as well as in-
depth immunological analysis of the natural immune response, including human and parasite 
transcriptomics, are currently underway. 

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Figure 2: Maximal severity of solicited AEs following P. vivax blood-stage CHMI in the VAC069 
study (n=6)  
Figure 3: Maximal severity of solicited AEs reported by all volunteers (n=6) in the VAC069 study 
at 0-48 hours prior to diagnosis, on day of diagnosis and 0-48 hours post-diagnosis  

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Page 45 of 128 
Volunteer 
Grade 3 AE 
Timepoint 
Persisted at grade 3 
Resolution 
6901002 
Feverishness
T+1 
24 hours 
T+2 
6901003 
Feverishness
DoD/C+12.5
48 hours 
T+2 
Chills 
T+1 
24 hours 
T+2 
Sweats 
T+1 
24 hours 
T+2 
Myalgia 
T+1 
24 hours 
T+2 
Fatigue 
T+1 
24 hours 
C+28 
Malaise 
T+1 
24 hours 
T+2 
6901006 
Feverishness
T+1 
24 hours 
T+2 
Chills 
T+1 
24 hours 
T+2 
Headache 
T+1 
24 hours 
T+2 
Fatigue 
T+1 
24 hours 
T+2 
Malaise 
T+1 
24 hours 
T+2 
6901009 
Feverishness
T+1 
24 hours 
T+2 
Rigor 
T+1 
24 hours 
T+2 
Table 3: Onset and duration of grade 3 solicited AEs reported by all volunteers (n=6) in the 
VAC069 study. T+1 = 1 day post-treatment initiation; DoD = day of diagnosis 
 
Figure 4: Percentage of all volunteers (n=6) with AEs in recorded physical observations 
Treatment related AE
 
Figure 5: AEs possibly relating to treatment in all volunteers (n=6) 
 

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Table 4: Laboratory AEs in biochemistry profile (urea and electrolytes, liver function tests) in all volunteers (n=6) in the VAC069 study 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Laboratory AE 
Volunteer
Timepoint(s)
Result 
Grade  
Action taken 
Hyponatraemia
6901003
C+28
134
1
No clinical concern, no action taken 
6901003
C+90
134
1
No clinical concern, no action taken 
Hypokalaemia 
6901002
C+90
3.3
1
No clinical concern, no action taken 
6901005
DoD
3.3
1
Repeated within 24 hours at next visit, resolved (3.7) 
6901003
C+90
3.3
1
No clinical concern, no action taken 
ALT 
6901003
T+6
135
2
Asymptomatic, repeated in 48 hours (80 - grade 1) and then resolved at C+28 (21) 
6901006
T+6
56
1
Repeated and resolved (29) at next visit (C+28), 
6901007
T+6
80
1
Repeated and resolved (31) at next visit (C+28)  
6901009
T+6
114
2
Asymptomatic, repeated in 72 hours and resolved (40)  

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Laboratory AE
Volunteer
Sex
Timepoint(s)
Result
Grade
Action taken
Anaemia 
6901002 
M 
T+6 
119 
1 
Repeated and resolved at next visit (C+28) 
6901005 
F 
C+16, C+34 (C+14-C+90) 
98 (98-109) 
(1-)2 
Monitored from C+14-C+90, AE ongoing at C+90 (102 - grade 1). Referred to GP for 
ongoing medical care, with follow-up of AE ongoing. 
Low white blood cell 
count 
6901002 
M 
T+1 
3.3 
1 
Consistent with P. vivax diagnosis, repeated and resolved (6.53) at next visit (T+6) 
6901003 
F 
T+1 
2.93 
1 
Consistent with P. vivax diagnosis, repeated and resolved (6.86) at next visit (T+6) 
6901005
F
T+1 (C+7-C+90)
1.68 (1.68-3.39)
(1-)2
Monitored from C+7-C+90, AE ongoing at C+90 (3.36 - grade1). Referred to GP for 
ongoing medical care, with follow-up of AE ongoing. 
6901006 
M 
T+1 (C+14-T+1) 
2.36 
2 
Monitored from C+14-T+6, resolved at T+6 (4.84) - consistent with P. vivax diagnosis 
Thrombocytopaenia 
6901003 
F 
T+1 
114 
2 
Consistent with P. vivax diagnosis, repeated and resolved (233) at next visit (T+6) 
6901005 
F 
T+1(DoD-T+1) 
115 (115-127) 
(1-)2 
Consistent with P. vivax diagnosis, repeated and resolved at T+6 (219) 
Neutropaenia 
6901005 
F 
C+45 (C+14-C+90) 
0.76 (0.76-1.46) 
(1-)2 
Monitored from C+14-C+90, AE ongoing at C+90 (1.26 – grade 1). Referred to GP for 
ongoing medical care, with follow-up of AE ongoing. 
Lymphocytopenia 
6901002
M
T+1 (DoD-T+1)
0.72 (0.72-0.86)
(1-)2
Consistent with P. vivax diagnosis, repeated and resolved at T+6 (1.63)
6901003 
F 
T+1 
0.77 
1 
Consistent with P. vivax diagnosis, repeated and resolved (2.53) at T+6  
6901005 
F 
DoD (DoD-T+1) 
0.44 (0.44-0.63) 
(2-)3 
Consistent with P. vivax diagnosis, repeated at resolved (1.63) at T+6 
6901006 
M 
T+1 (C+14-T+1) 
0.3(0.3-0.83) 
(1-)3 
Consistent with P. vivax diagnosis, repeated and resolved at T+6 (2.07) 
Table 5: Laboratory AEs in full blood count in all volunteers (n=6) in the VAC069 study 

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5.3 
Conduct of CHMI trials 
5.3.1 Standardisation of CHMI studies 
Following a collaborative consensus process involving investigators from the USMMVP, Sanaria, 
University of Maryland, University of Oxford, RUNMC, The Seattle Biomedical Research Institute 
and the KEMRI-Wellcome Kilifi Research Programme, a consensus document; “Standardization of 
Design and Conduct of P. falciparum Sporozoite Challenge Trials” was developed, and provides a 
comprehensive guide to the appropriate conduct of sporoziote CHMI studies [95]. There is no 
equivalent document for controlled blood-stage infection or for P. vivax challenge, however, this 
study will be conducted in line with the following key points.  
 All volunteers should have a medical assessment no longer than 48 hours before 
challenge, including an interim medical history, directed physical examination, pregnancy 
test for female volunteers. 
 Volunteers should be questioned about the occurrence of adverse events and use of 
medication at each follow-up visit. 
 In the event that a volunteer does not attend a scheduled follow-up visit it is imperative 
that Investigators find that volunteer as quickly as possible and assess them for patent 
parasitaemia and clinical malaria. Should the volunteer withdraw consent from further 
follow-up prior to receipt of antimalarial drugs, it may be appropriate to withdraw the 
volunteer from the trial protocol and administer a course of antimalarial chemotherapy 
under close supervision.  
 Grading and reporting of adverse events should be performed using international and 
local guidelines. It should be noted that the occurrence of a low frequency of grade 3 
severe adverse events, of short duration, and with no long-term sequelae, is not 
unexpected in CHMI studies. A minority of those challenged are known to experience 
grade 3 systemic adverse events and this fact should be included in the informed consent 
form. 
 Vital signs should be recorded at least once daily and at any subsequent visits for medical 
attention. Directed physical examination should be performed when necessary.  
 It is critical that every volunteer must receive every dose of anti-malarial therapy. In some 
settings fully directly observed treatment will be essential. Where directly observed 
treatment is not used, Investigators must follow volunteers closely to ensure compliance 
with the treatment regimen.  
 After challenge, all volunteers should be followed until they have completely finished 
anti-malaria treatment.  
 Volunteers should be evaluated at least two weeks after finishing treatment. 
 A local safety monitor and an independent safety monitoring committee should be 
established to act as independent experts in evaluating adverse events. The safety 
monitor or monitoring committee may advise the Investigators on initiating anti-malarial 
treatment for a specific volunteer or volunteer group. While safety monitoring 
committees are not a requirement for Phase I trials, they should be considered a 
requirement for CHMI trials which have an efficacy/human challenge component and 
which have major potential safety concerns. 
5.3.2 Ethical considerations of CHMI trials 
Participants in CHMI trials are healthy volunteers who do not obtain direct health benefit from 
participation. Challenge trial investigators must exercise all possible safeguards for volunteer 
safety to ensure that trial participation is of minimal risk. Investigators must also ensure that 

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Page 49 of 128 
maximal scientific benefit accrues from each challenge trial. Key ethical considerations agreed by 
consensus of the field are outlined in a review by Moorthy from 2011, and include; [95]   
1. Volunteer safety is the paramount consideration in conduct of CHMI trials.  
2. Adherence to both international and local guidelines with respect to ethical 
considerations and in accordance with the Declaration of Helsinki and local regulatory 
and ethics committee requirements.  
3. CHMI trials should be conducted according to ICH and/or WHO Good Clinical Practice 
Guidelines with the aim of maximising scientific benefit whilst minimising risk. 
4. The raw data (both microscopy and PCR where available) from challenge trial datasets 
should be made publicly available to facilitate scientific benefit to the community.  
5. If an unexpected SAE which is possibly related to CHMI occurs at a challenge trial centre, 
recognising legal restrictions, every effort should be made to communicate information 
on this SAE to the community of challenge trial centres within 90 days of the occurrence 
of the SAE.  
5.3.3 Clinical presentation post-CHMI 
Nearly all unvaccinated volunteers in CHMI studies develop symptoms of clinical malaria 
infection; based on data predominately from P. falciparum challenge studies approximately one-
fifth of volunteers temporarily develop symptoms graded as severe (symptoms that prevent daily 
activities), but severe or life-threatening malaria has never occurred [117]. The expected time-
course, symptoms and management of clinical malaria are outlined in Sections 8.5.4, 11.4 and 
11.5.  
Routine laboratory checks generally show a moderate decrease in leukocyte and platelet 
numbers during infection, with no change in haemoglobin concentration [118]. Bleeding or 
thrombogenic complications have never been described [117, 118]. Abnormalities of liver 
enzymes have been observed, but these abnormalities have rarely resulted in clinical 
manifestations (just one volunteer with raised ALT associated with abdominal pain and vomiting 
in the recent RCT from Cali [27]) and they resolved after a few days.  
It is estimated that human malaria challenge infections have now been conducted with P. 
falciparum in over 2,650 volunteers and in approximately 300 volunteers with P. vivax [119]. In 
2009, safety concerns were raised when young volunteer suffered a cardiac event shortly after 
treatment for diagnosed malaria, following a P. falciparum challenge. This was diagnosed as 
probable myopericarditis, although ischaemia could not be ruled out. Although a definite 
relationship between the cardiac event, which resolved fully and rapidly, and the experimental 
malaria infection was not established [120], it has been generally agreed that volunteers with an 
increased risk of cardiac disease should be excluded from such trials [95]. A further case of 
myopericarditis has since been identified in a recent P. falciparum CHMI study, also at the 
Nijmegen, Netherlands centre, but in this case the individual was also diagnosed with an 
intercurrent rhinovirus infection so that the relation to malaria infection is again uncertain. There 
was a brief episode of clinical chest pain and the volunteer made a full recovery [121]. 
5.3.4 Oxford’s experience conducting CHMI trials 
The University of Oxford has been conducting CHMI studies (with P. falciparum) for the last 18 
years. To date, nearly 600 volunteers have undergone CHMI in studies conducted by the 
University of Oxford, including more than 180 unvaccinated volunteers. An analysis has shown 
that the symptoms of malaria experienced by volunteers undergoing sporozoite challenge by 
mosquito bite in Oxford are broadly similar to those experienced by volunteers challenged by 
mosquito bite at Radboud University Nijmegen Medical Center (RUNMC) and the US Military 

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Malaria Vaccine Program (USMMVP) [122]. In Oxford, four volunteers amongst nearly 600 
individual challengees have required admission to hospital for observation following challenge 
(SAE related to CHMI). All of these subjects made a complete recovery. This will be only the 
second blood-stage P. vivax challenge study conducted in Oxford, but we have based our study 
design on that of the previous P. vivax blood-stage challenge studies in Australia, combined with 
our own extensive experience of P. falciparum sporozoite challenge studies and our recent 
VAC068 P. vivax sporozoite challenge study.  
In one Phase I/IIa sporozoite challenge study assessing the efficacy of viral vectored malaria 
vaccines in Oxford (VAC039; Clinicaltrials.gov reference: NCT01142765), a volunteer who 
underwent sporozoite challenge on 1st October 2010 failed to attend his next scheduled study 
visit on 7th October 2010 [83]. The police were immediately informed and began a nationwide 
search for the individual. All volunteers had been informed at screening that the police would be 
notified should they go missing following CHMI if they had not completed a full course of an 
appropriate anti-malarial treatment. The volunteer was found in the Netherlands by the local 
police 17 days following CHMI. He then had very mild malaria symptoms. He was admitted to a 
local hospital where he received appropriate treatment for P. falciparum. He had no signs of 
severe malaria but showed an altered mental state considered unrelated to malaria with 
apparent memory loss and suicidal ideation. He was therefore transferred for in-patient 
psychiatric assessment and discharged a few days later to his GP’s care. He has subsequently 
been reportedly diagnosed as schizophrenic. 
It emerged that from 2nd October 2010, the day after CHMI, the volunteer had experienced an 
alteration in his expected behaviour following his arrest the previous evening by the police 
relating to their investigation of a serious crime, of which he was later convicted. This arrest 
appeared to trigger his leaving home and disappearance and appears relevant to the subsequent 
finding of memory loss and suicidal ideation. It emerged on subsequent investigation that the 
volunteer actually had a history of some psychiatric morbidity pre-dating his involvement in the 
study by many years, which was not disclosed at screening by the volunteer or his GP. Of note, 
the volunteer had attended 9 clinic visits prior to challenge and appeared a reliable and 
appropriate volunteer.  
This event was extensively discussed with investigators, colleagues and appropriate authorities 
and non-study related causality agreed. Given the exceptional circumstances relating to this case, 
it seems very unlikely that a similar event would happen again in the future. Management of the 
event was extensively reviewed by the trial’s sponsor, the MHRA and ethical committee who felt 
that appropriate and timely action was taken. Follow-up procedures following CHMI have been 
reviewed locally, and it has been decided that for future studies volunteers should be contacted 
daily on days 1-5 post sporozoite challenge in order to make sure they are contactable and well. 
Daily telephone contact will similarly be conducted in this study on days 1-6, before daily clinic 
visits commence on day 7.  
5.3.5 Conducting CHMI in the context of the COVID-19 pandemic 
Due to the COVID-19 pandemic this trial was temporarily halted in March 2020. The incidence of 
COVID-19 continues to change in England and some ongoing transmission is likely to remain 
when this trial restarts in 2021 [123]. This trial will only proceed when rates of COVID-19 
infections in England are low and the risk of contracting COVID-19 during malaria challenge is 
small, however the risk cannot be eliminated. There is currently no evidence for the possible 
effects of co-infection with malaria and COVID-19. As the risk of co-infection cannot be 
quantified, participants will be tested for COVID-19 prior to malaria challenge and any participant 
that tests positive for COVID-19 will not proceed with malaria challenge.  

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Participants who test positive for COVID-19 will be advised to self-isolate as per Public Health 
England guidance and directed to local NHS services for further care if required. COVID-19 PCR 
results will be reported as a notifiable disease as per Public Health England guidance. 
Fevers which occur following malaria challenge may pose diagnostic difficulties as concurrent 
COVID-19 infection will likely remain an ongoing possibility in England. Data from the 12 primary 
and 4 secondary CHMI with P. vivax conducted in Oxford to date, show that no participants 
developed symptoms that are consistent with malaria within the first week post challenge. 
Pyrexia or subjective feelings of feverishness occurred in only half of the participants prior to 
diagnosis and treatment of malaria. However the majority of remaining participants who were 
initially apyrexial, did subsequently develop fever after commencing malaria treatment, although 
this was short lived and resolved within 2 days. Following malaria challenge, participants first 
developed pyrexia or subjective feelings of feverishness between days 10 to 20 post challenge 
(median 14 days), with corresponding malaria qPCR levels of 100 to 9600 genome copies/mL 
(median 2700 genome copies/mL). No recorded pyrexia of >37.8°C occurred at a malaria qPCR 
below 1000 genome copies/mL in any participant. Malaria diagnosis was made in participants 
within a few days following the onset of symptoms with some participants reporting no 
symptoms prior to laboratory diagnosis. Participants were diagnosed with malaria based on a 
combination of clinical symptoms, malaria qPCR and thick film microscopy between days 12 and 
21 post challenge (median 15.5 days).  
Fevers within the first week after malaria challenge are therefore unlikely to be due to malaria. 
After the first week post challenge, malaria as the cause of fever becomes increasingly likely with 
increasing time since challenge. However, as concurrent COVID-19 infection will likely remain a 
possibility, testing for COVID-19 has been added in the post-challenge period for participants 
who become febrile. For participant safety, if a participant tests positive for COVID-19 prior to 
malaria diagnosis, they will be treated for malaria regardless of if they have reached the criteria 
for malaria diagnosis.  
There is no evidence for any detrimental effect of anti-malarial medication on the outcome of 
concurrent COVID-19 infection. This is in the context of widespread antimalarial use during the 
COVID-19 pandemic in Africa, where no safety signal has emerged. Recent randomised controlled 
trials have shown no benefit of Hydroxychloroquine in COVID-19 [124], but also no harm, and 
Chloroquine will not be used for malaria treatment in this trial. The anti-malarial medications 
Riamet and Malarone are not expected to have any effects on the outcome of COVID-19 disease. 
Social distancing requirements to control COVID-19 will likely remain in place to some extent in 
England. To abide with these, participants’ attendances at study clinics will be carefully planned 
to adhere to social distancing guidelines. Participant flow will be arranged so that contact with 
other people is minimised and Personal Protective Equipment (PPE - compromising apron, 
gloves, surgical mask and eye protection) will be worn by members of clinical staff for all 
participant visits. This will follow an infection control SOP that covers all PPE requirements for 
clinical trials at the Oxford Vaccine Centre in the era of the COVID-19 pandemic. Any clinic visits 
that are carried out on a participant that is self-isolating will be conducted in a separate clinical 
area with side access to avoid any contact with other volunteers. 
As the national rollout of COVID-19 vaccines proceeds, some participants may be offered a 
COVID-19 vaccine around the time of planned malaria challenge. It is unknown what effect 
concomitant COVID-19 vaccine administration around the time of CHMI may have on the 
immune response to malaria infection, which is being studied in this trial. In addition 
reactogenicity from COVID-19 vaccination may be difficult to distinguish from symptoms of 
malaria and may lead to earlier diagnosis and treatment of malaria after challenge. Therefore 

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concomitant COVID-19 vaccination around the time of CHMI has been added as an exclusion 
criteria in this trial. 
 

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6 INVESTIGATIONAL PRODUCTS 
6.1 ChAd63 PvDBP 
ChAd63 PvDBP was manufactured under Good Manufacturing Practice (GMP) conditions by the 
CBF, University of Oxford. ChAd63 PvDBP is supplied as a liquid in sterile aliquots in 2.0 mL clear 
glass vials. Further details relating to batch release and manufacturing can be found in the 
ChAd63 PvDBP IMP-D.   
6.2 MVA PvDBP 
MVA PvDBP was manufactured under Good Manufacturing Practice conditions by IDT, Germany. 
MVA PvDBP is supplied as a liquid formulation in Tris buffer. The virus suspension is supplied as 
sterile aliquots in 2.0 mL clear glass injection vials. Final batch certification and associated 
labelling takes place at the CBF, University of Oxford. Further details relating to batch release and 
manufacturing can be found in the MVA PvDBP IMP-D.   
6.3 Storage of Vaccines  
All vaccines will be stored between –70°C and –90°C. All movements of the study vaccines will be 
documented. Vaccine accountability, storage, shipment and handling will be in accordance local 
SOPs.  
6.4 Administration of Vaccines 
All vaccines will be administered intramuscularly in the deltoid muscle of arm, according to SOP 
VC002 Vaccination. The vaccinating investigator will wear gloves and eye protection. During 
administration of the vaccines, Advanced Life Support drugs and resuscitation equipment will be 
immediately available for the management of anaphylaxis. On vaccination day, vaccines will be 
allowed to thaw to room temperature and administered within 1 hour. Depending on dose and 
concentration, one or more vials of vaccine may be used.   
6.5 Minimising environmental contamination with Genetically Modified Organisms (GMO) 
The study will be performed in accordance with UK Genetically Modified Organisms (Contained 
Use) Regulations (2000). In order to minimise dissemination of the recombinant vectored vaccine 
virus into the environment, inoculation sites will be covered with a dressing after immunisation. 
This should absorb any virus that may leak out through the needle track. The dressing will be 
removed from the injection site after 30 minutes (+/- 5 minutes) and will be disposed as GMO 
waste by autoclaving. 
6.6 Vaccine Supply 
ChAd63 PvDBP will be supplied to the clinical site by the CBF, University of Oxford. At the CBF the 
vaccines are formulated, vialed and labelled for investigational use only.  
MVA PvDBP will be supplied to the CBF, University of Oxford, by IDT, Germany where the 
vaccines are formulated and vialed. They will be labelled for investigational use only by the CBF, 
who will then transfer the vaccines to the clinical site.  
All vaccines will be certified for release by a qualified person (QP) at the CBF, University of 
Oxford.  
 
 

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7 OBJECTIVES AND ENDPOINTS 
7.1 Primary Objectives  
To assess efficacy of the ChAd63 and MVA PvDBP vaccines, administered in a heterologous 
prime-boost regimen, as assessed by a reduced parasite multiplication rate in vaccinated 
subjects 
7.2 Primary Outcome Measures 
Quantitative PCR-derived parasite multiplication rate (PMR) will be the primary efficacy endpoint 
and a comparison of the endpoint between Groups 1 and 2 (pooled data) and malaria-naïve 
controls partaking in simultaneous CHMI, under identical conditions, will constitute the primary 
analysis for efficacy.  
The arithmetic mean of the three replicate PCR results obtained for each individual at each 
timepoint will be used for model-fitting. Negative individual replicates will be handled as 
specified in the Jenner Institute qPCR SOP. qPCR data points which, based upon the mean of the 
three replicates, are negative or below the limit of quantification will be handled as specified in 
the Jenner Institute qPCR SOP. PMR will be calculated using a linear model fitted to log10-
transformed qPCR data.  
The distribution of PMRs will be assessed for deviation from normality visually and using a 
d’Agostino-Pearson test. Standard ladder-of-power transformations may be applied to achieve 
normality. Equality of variance will be tested with an F test. In the event of deviation from 
normality, PMRs will be compared by two-tailed Mann-Whitney test; otherwise a two-tailed two-
sample t-test will be used, with Welch’s correction if variances are non-equal as assessed by F-
test.  
7.3 Secondary Objectives 
To assess safety and tolerability of the ChAd63 and MVA PvDBP vaccine candidates, administered 
in a heterologous prime-boost regimen in a CHMI study in healthy volunteers 
To assess the humoral and cellular immunogenicity ChAd63 and MVA PvDBP vaccine candidates, 
administered in a heterologous prime-boost regimen 
To assess immunological readouts for association with a reduced parasite multiplication rate 
7.3.1 Secondary Safety Outcome Measures 
The specific endpoints for safety and reactogenicity will be actively and passively collected data 
on adverse events. The following parameters will be assessed:  
 Occurrence of solicited local reactogenicity signs and symptoms for 7 days following each 
vaccination  
 Occurrence of solicited systemic reactogenicity signs and symptoms for 7 days following 
the vaccination  
 Occurrence of unsolicited adverse events for 28 days following the vaccination  
 Change from baseline for safety laboratory measures for 28 days following vaccination 
 Occurrence of serious adverse events during the whole study duration  
 
Solicited and unsolicited AE data will be collected at each clinic visit. It will be collected from 
diary cards, clinical review, clinical examination (including observations) and laboratory results. 

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This AE data will be tabulated and frequency, duration and severity of AEs compared for each of 
Groups 1 and 2 against the AE data collected for the infectivity control group undergoing 
simultaneous CHMI, under identical conditions, recruited as part of the VAC069 clinical trial.  
Hematological and biochemical laboratory values will be presented according to local grading 
scales and tabulated by group, for comparison with the laboratory AE data collected for 
infectivity control groups undergoing CHMI in parallel.  
SAEs and withdrawal due to AE(s)/SAE(s) will be described in detail. 
Groups 1 and 2 will be followed for approximately 1 year following priming with ChAd63 PvDBP 
and approximately 10 months following boost with MVA PvDBP. 
7.3.2 Secondary Immunological Outcome Measures 
PvDBP_RII -specific immunogenicity will be assessed by a variety of immunological assays, with 
comparison before and after vaccination. The main outcome measures will be humoral and B cell 
responses to the P. vivax Duffy-binding protein (PvDBP) – total IgG; T cell responses to PvDBP by 
flow cytometry assays and in vitro functional PvDBP_RII  inhibitory binding assays. Other 
established and exploratory immunology assays including IgG isotypes and avidity may be carried 
out, including through collaboration with other specialist laboratories, which may be outside of 
Europe. This would involve transfer of serum/plasma, but samples would be anonymised. 
Volunteers will be consented for this. 
The relationship between PMR in vaccinated subjects and anti-PvDBP_RII  antibody responses 
induced by the ChAd63 PvDBP and MVA PvDBP vaccines and PMR will also be assessed.  
 
All other analyses will be reported as not pre-specified in the trial protocol. Other analyses may 
be detailed in the VAC071 laboratory plan. Some assays may be duplicated at different sites. 
Some of these will involve analysis of frozen samples, and others analysis of fresh samples. 
 
 
 
 
 
 

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8 DESCRIPTION AND JUSTIFICATION OF STUDY DESIGN  
8.1 
Study rationale  
As outlined above, the available methods for preventing and treating infections with P. vivax in 
the field are inadequate. An effective vaccine against P. vivax would contribute significantly to 
disease control and elimination efforts. Currently, only two P. vivax candidate vaccines, both 
targeting the pre-erythrocytic stage, have progressed to Phase II studies. CHMI efficacy data for 
only one of these candidates, VMP001/AS01B, is still currently published and whilst the vaccine 
was well-tolerated and immunogenic, there was no efficacy following sporozoite challenge.  
The ChAd63-PvDBP and MVA-PvDBP vaccine candidates, administered in a heterologous prime-
boost regimen, have been demonstrated to be safe, tolerable and immunogenic in an open-label 
dose-escalation Phase Ia study [106]. Progression of these promising candidate vaccines into this 
Phase IIa challenge study will be the first trial of efficacy of a P. vivax blood-stage vaccine 
candidate. Even if partially efficacious, through a reduced parasite multiplication rate, this could 
represent an important tool reducing the P. vivax global health burden and moves towards 
elimination. Assessment of efficacy in this study will therefore inform future progression of these 
novel vaccines into further clinical testing into larger, but more expensive and logistically 
demanding trials, in the endemic setting.  
The small numbers in the lead-in group, in the first stage of this study is intended to assess safety 
of the P. vivax blood-stage challenge model following exposure to blood-stage antigens via viral-
vectored vaccination, known to be strong inducers of effector T-cell responses. Data from murine 
models has highlighted a theoretical risk of immunopathology mediated by cytokine imbalance, 
resulting from a potent T-cell response. To date, there have been no concerns in any human 
study testing similar P. falciparum blood-stage vaccines in malaria challenge, but this initial small 
group will provide further clinical data, to assure safety of CHMI following vaccination with a P. 
vivax blood-stage candidate. If demonstrated to be safe, the same regimen will be administered 
to a further group of 10-12 volunteers to allow assessment of efficacy, pooling data on the 
parasite multiplication rate (PMR) from both groups, and comparing with PMR data from  
malaria-naïve controls undergoing simultaneous CHMI (partaking in another parallel study, 
VAC069).   
8.2  Study Overview 
This is an open-label, single-centre Phase IIa P. vivax blood-stage CHMI trial to assess the efficacy 
of the candidate malaria vaccines ChAd63 and MVA PvDBP. Up to 19 healthy, malaria-naïve 
adults aged between 18 and 45 years will be recruited at the CCVTM, Oxford over 2 and a half 
years.  
Initially, to assure safety of challenge following vaccination, a pilot safety study will be carried 
out in three volunteers (Group 1), receiving the ChAd63 and MVA PvDBP vaccines 
intramuscularly, administered at an 8-week interval, in a heterologous prime-boost regimen. 
Approximately 4 weeks (2-4 weeks) post-boost, volunteers will undergo P. vivax blood-stage 
CHMI, induced by injection of P. vivax infected erythrocytes. Volunteers will have blood taken at 
regular intervals following vaccination and in the post-CHMI period to assess the immune 
response to vaccination and subsequent challenge, as well as parasite growth dynamics and 
gametocytaemia. Close monitoring will continue until volunteers meet criteria for treatment or 
until 28 days after challenge in Group 1 or 21 days in Groups 2 and 3, when treatment will be 
started empirically.  

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Therapy will be with a standard 60-hour course of oral artemether-lumefantrine (Riamet®), 
where not contraindicated. As infection will be mediated via intravenous injection of blood-stage 
parasites, there will be no liver-stage infection and no hypnozoite formation, thereby eliminating 
need for radical cure with primaquine therapy.   
Following completion of treatment of all Group 1 volunteers, and pending satisfactory review of 
safety, a further ten to twelve volunteers (Group 2) will be enrolled. Group 2 volunteers were 
originally planned to receive vaccinations and subsequent challenge according to the same 
schedule as the pilot study (Group 1) volunteers. However, volunteers enrolled in Group 2 only 
received the ChAd63 PvDBP vaccine before the trial was temporarily halted in March 2020 due to 
the COVID-19 pandemic. On restart of the trial after a pause of approximately one year, 
volunteers in Group 2 will receive a repeat ChAd63 PvDBP vaccination followed by MVA PvDBP 
vaccine 8 weeks later.  
If fewer than 6 volunteers complete the study in Group 2, new volunteers will be recruited into 
Group 3, to make up a total of 6 volunteers between Groups 2 and 3 who complete all 
vaccinations and CHMI. Volunteers in Group 3 will undergo vaccinations and CHMI at the original 
schedule as the pilot study (Group 1) volunteers.  
During each CHMI period, a matched number of malaria-naïve infectivity controls, recruited as 
part of the VAC069 study, will be challenged under identical conditions and in parallel.  
All vaccinations, follow-up visits, CHMI and follow-up in the post-challenge period will be 
performed at the CCVTM in Oxford. Follow-up will be for approximately 1 year after the last 
vaccination for each group.  
8.3 
Study groups 
Originally two study groups were planned, Group 1 and Group 2, comprising 3 and 10-12 
volunteers, respectively. Group 1 volunteers will constitute the pilot safety phase of the study, 
undergoing vaccinations and CHMI prior to Group 2 volunteers. At least 2/3 Group 1 volunteers 
will need to have completed 28 days of follow-up post challenge (and at least 6 days of follow-up 
post completion of antimalarials) before enrolment of Group 2 volunteers can begin. This is to 
facilitate independent review of safety data and adverse events by the Local Safety Monitor. If 
there are no safety concerns, enrolment of Group 2 volunteers may commence. This, however, 
will not affect screening procedures for either group and volunteers may be screened to be 
recruited into Group 2, prior to review of Group 1 safety data. Volunteers will be able to choose 
which group they are allocated to (provided there is still space in the group they wish to be in).  
This trial was temporarily halted in March 2020 due to the COVID-19 pandemic, after participants 
in Group 2 had completed their first vaccinations with ChAd63 PvDBP. On restart of the trial after 
a halt of approximately 1 year, a proportion of participants will be expected to be lost to follow-
up. If fewer than 6 participants complete the study in Group 2, then new volunteers will be 
recruited into an additional group - Group 3, to make up a total of 6 volunteers between Groups 
2 and 3 who complete all vaccinations and CHMI. Group 3 volunteers will undergo vaccinations 
and CHMI at the original schedule. 
8.3.1 Group 1 
Three volunteers will be recruited into Group 1 and will attend for two vaccinations. On the day 
of enrolment, ChAd63 PvDBP will be administered at a dose of 5x1010 vp. Approximately 8 weeks 
later, MVA PvDBP will be administered, at a dose of 2x108 pfu, followed by blood-stage CHMI at 
approximately 4 weeks (2-4 weeks) post-boost. Volunteers will be followed until 1 year, from the 
time of enrolment.   

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8.3.2 Group 2 
If there are no concerns following review of Group 1 safety CHMI data, ten to twelve volunteers 
will be recruited into Group 2. Group 2 volunteers were originally planned to receive two 
vaccinations followed by CHMI, at the same dose and according to the same schedule as Group 1 
volunteers. However, the trial was temporarily halted after 10 volunteers in Group 2 received 
one dose of ChAd63 PvDBP vaccine. On restart of the trial after approximately one year, those 
volunteers that continue in the study will receive a second dose of ChAd63 PvDBP 5x1010 vp, 
followed by 2x108 pfu MVA PvDBP at 8 weeks and blood-stage CHMI approximately 4 weeks (2-4 
weeks) after booster vaccination. Volunteers will be followed until approximately 2 years from 
the time of enrolment.   
In addition, two “back-up” volunteers may be recruited for Group 2. These volunteers will be 
vaccinated alongside the rest of the group and attend the C-1 visit but will only undergo malaria 
challenge if another Group 2 volunteer drops out of, or is withdrawn from, the study. The back-
up volunteers may be asked to attend clinic on day of challenge in case another control volunteer 
is found to be ineligible at that point. If back-up volunteers are not required on day of challenge 
they will continue to be followed-up for 6 months.  
8.3.3 Group 3 
A proportion of volunteers in Group 2 are expected to be lost to follow-up due to the long 
duration of the trial halt. If fewer than 6 volunteers in Group 2 complete the study, new 
volunteers will be recruited into Group 3, to make up a total of 6 volunteers across groups 2 and 
3 who complete vaccinations and subsequent CHMI. Group 3 volunteers will undergo two 
vaccinations and CHMI at the same schedule as Group 1 volunteers: 5x1010 vp ChAd63 PvDBP, 
followed by 2x108 pfu MVA PvDBP at 8 weeks and blood-stage CHMI approximately 4 weeks (2-4 
weeks) after the second vaccination. 
8.3.4 Control groups during challenge  
Malaria-naïve controls for CHMI, will be recruited as part of the currently ongoing VAC069 study, 
a P. vivax challenge study to assess safety and feasibility of the blood-stage P. vivax challenge 
model, and to assess the effect of previous challenge on subsequent homologous re-challenge. 
Malaria-naïve controls recruited in the VAC069 study will undergo primary challenge in parallel 
with CHMI for all Groups (1, 2 and 3) volunteers in this study, i.e. simultaneously and under 
identical conditions. Group 1 volunteers will undergo CHMI in parallel with VAC069 Group 6 
volunteers (n=3) and Group 2 and 3 volunteers will receive CHMI in parallel with VAC069 Group 
12 volunteers (n=8). Where consent is obtained, the data generated from the challenge of 
malaria-naïve controls within the VAC069 study will be utilised on an anonymous basis, for 
comparative analysis with challenge of VAC071 vaccinees for assessment of vaccine efficacy. 
 
Group 
Group size 
D0 
D56 
D84 
Group 1 
 
3 
ChAd63 PvDBP 
5x1010 vp 
MVA PvDBP 
2x108 pfu 
CHMI 
Group 3 
 
 1-6 
ChAd63 PvDBP 
5x1010 vp 
MVA PvDBP 
2x108 pfu 
CHMI 
Table 6a: Study groups 1 & 3 New participants will only to be recruited into Group 3, if fewer than 6 
participants in Group 2 complete all vaccinations and CHMI, to make up a total number of 6 participants between 
Groups 2 and 3. 

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Group 
Group 
size 
D0 
Trial 
halt  
12-18 months 
56 days post 
2nd vaccination 
84 days post 
2nd vaccination 
Group 2 
 
10-
12(+2) 
ChAd63 PvDBP 
5x1010 vp 
 
ChAd63 PvDBP 
5x1010 vp 
MVA PvDBP 
2x108 pfu 
CHMI 
Table 6b: Study group 2 
 
8.4 
Duration of study 
8.4.1 Definition of the start and end of the trial  
The start of the trial is defined as the date of the site initiation visit (SIV). The end of the trial is 
the date of the last follow-up of the last volunteer. 
8.4.2 Duration of volunteer participation 
Volunteers will be considered to be enrolled in the trial on the receipt of the first vaccination. 
Total duration of follow-up will be 1 year from enrolment for groups 1 and 3. Total duration of 
follow-up will be 2 to 2.5 years from enrolment for group 2, which has been extended by 
approximately 1 year due to the temporary trial halt (with the exception of the back-up 
volunteer(s) in Group 2, who will only be followed for 6 months, for safety reasons).  
8.5 
Potential risks for volunteers 
8.5.1 Phlebotomy  
The maximum volume of blood drawn over the study period should not compromise these 
otherwise healthy volunteers. There may be minor bruising, local tenderness or pre-syncopal 
symptoms associated with venepuncture, which will not be documented as AEs if they occur. The 
total volume of blood taken over the study period will vary by group. The actual total blood 
volume will relate to the timing of malaria diagnosis and treatment during challenge.  
Male regular blood donors may donate one unit (470mL) every 12 weeks and females every 18 
weeks. However, a recent multicentre study by NHS Blood and Transplant (in Oxford and 
Cambridge) compared outcomes in 50,000 regular blood donors who were randomised to 
different intervals between blood donations (as regularly as giving 470 mL every 8 weeks in male 
participant group and every 12 week in females) over 2 years. There were no significant 
differences were observed in quality of life, physical activity, or cognitive function although there 
were more symptoms related to blood donation, in groups donating more frequently, including 
tiredness, breathlessness, feeling faint, dizziness and restless legs. Symptoms were most 
increased among male participants.  Lower mean haemoglobin and ferritin concentrations were 
also detected.  
In this study, participants will never donate 470mL of blood in one sitting; the maximum volume 
they will donate in a single visit is 98mL so we would not expect them to report a high frequency 
of symptoms at the time of or just after blood donation. They will be closely monitored at all 
times of blood donation, and haemoglobin will be checked regularly, as described in the study 
procedures. Any abnormal result will be re-checked and referred to the GP for further 
investigation and management, as deemed clinically appropriate by the Investigator.  
The maximum total blood volume drawn in this study will be 1327mL over 1 year. For male 
participants, this is 1728mL less than the 8-week interval group in the NHSBT study and for 

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females, 710mL less than the 12-week interval group, over the 1 year period. Therefore, we are 
confident that this volume should not compromise our volunteers. However, the additional 
effect of malarial infection on potential anaemia is acknowledged. For this reason, the full blood 
count will be monitored throughout the study period. 
8.5.2 Vaccinations 
Potential expected risks from vaccination, which include local and systemic reactions are specific 
to each IMP and are described below, with full details available in the respective IBs.  
As with any vaccine, Guillain-Barré syndrome or immune-mediated reactions that can lead to 
organ damage including serious allergic reactions may occur but this should be extremely rare. 
Serious allergic reactions including anaphylaxis could also occur and for this reason volunteers 
will be vaccinated in a clinical area where Advanced Life Support trained physicians, equipment 
and drugs are immediately available for the management of any serious adverse reactions. 
(a) ChAd63 PvDBP (see also IBs for IMPs) 
Based on the safety data available from the 24 volunteers who received ChAd63 PvDBP in the 
VAC051 Phase Ia study, as well data available from more than 950 individuals who have 
previously received ChAd63 vectored vaccines, the below adverse event profile is expected 
following vaccination with ChAd63 PvDBP. 
Local adverse events such as pain would be expected to occur frequently. Less frequent adverse 
events are likely to include erythema, swelling, itching and warmth.  Local AEs are likely to be 
mild in nature and should resolve rapidly, although there is the possibility of moderate or severe 
arm pain in some cases.   
Common systemic adverse events post viral vectored vaccines include headache, feverishness, 
myalgia, arthralgia, fatigue and malaise. Generally volunteers report a transient ‘flu-like illness” 
within 24 hours of vaccination with ChAd63 which usually resolves within 48 hours. Given 
existing data for ChAd63 vectored vaccines, the majority of systemic AEs are likely to be mild in 
intensity but there is a possibility of transient moderate or severe systemic symptoms. 
Moderately elevated aminotransferase or moderately elevated eosinophil counts may be seen in 
vaccinees in the two weeks following vaccination with ChAd63 vectored vaccines which, if they 
occur, are likely to resolve fully.  
During the manufacturing process of ChAd63 vectored vaccines, a biocide named Kathon is used.  
Kathon is added to body washes, conditioners, liquid soaps, shampoos and wipes as a 
preservative. The maximum dose is 0.1% for ‘rinse off’ products and for ‘leave on’ products it is 
0.05%. It has been approved by regulatory authorities throughout the world as a preservative in 
these products. As a skin sensitiser it is known to cause contact dermatitis. An internal study was 
set up to look at the levels of Kathon that were removed during the final purification step of 
buffer exchange. This study utilized high performance liquid chromatography and showed that 
trace amounts of Kathon may be left on the column after carrying out the rinse and sanitisation 
steps. However, the study confirmed greater than 99.9975% removal of Kathon to approximately 
30-fold less than the limits for ‘leave on’ products containing Kathon. We will exclude anyone 
from the study with a history of clinically significant contact dermatitis or sensitivity to Kathon.  
Adenovirus vaccines including ChAd63 vaccines against different diseases have previously been 
trialled in human volunteers without serious adverse events. However two recently developed 
vaccines against COVID-19, which are based on adenoviruses as the viral vector of the vaccines, 
may be associated with serious thromboembolic events with concurrent thrombocytopenia 

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following vaccination. These two vaccines are the Oxford/AstraZeneca vaccine, which uses a 
chimpanzee adenovirus (ChAdOx1), and the Janssen COVID-19 vaccine, which uses human 
adenovirus type 26 (Ad26) as the vector. Reported cases include life-threatening and fatal cases 
of venous thrombosis at unusual sites, in particular cerebral venous sinus thrombosis, as well as 
arterial thrombosis, combined with thrombocytopenia. For the Oxford/AstraZeneca vaccine the 
UK Medicines and Healthcare products Regulatory Agency (MHRA) has concluded that the 
evidence of a link between this clotting disorder is stronger but further investigations are 
ongoing. The overall risk of developing these blood clots is very low at approximately 4 people 
in a million who receive the Oxford/AstraZeneca vaccine [125]. To date there have been no 
reports of this clotting disorder following a second vaccination with the Oxford/AstraZeneca 
vaccine, however only a relatively small number of second doses have been given so far. For the 
Janssen COVID-19 vaccine, as of 20th April, more than 7 million doses of the vaccine have been 
administered in the US and there have been 8 reported cases of the clotting disorder following 
a single dose [126].  
It is not known whether these rare clotting problems might be related to the viral vector itself 
(ChAdOx1 or Ad62), or to the SARS-CoV-2 part of the vaccine. As both the viral vector and the 
gene insert differ between the ChAd63 PvDBP malaria vaccine used in this trial and the two viral 
vectored COVID-19 vaccines, it is unknown whether this rare clotting disorder could potentially 
occur with the ChAd63 PvDBP vaccine. These rare blood clotting problems have never been seen 
in participants in trials involving other ChAd63 vaccines in the past, however the number of 
people in these trials has been relatively small, so rare events may not be captured.  
(b) MVA PvDBP (see also IBs for IMPs) 
In addition to the safety data available from the 15 volunteers who have previously received this 
vaccine in the Phase Ia study, safety information available from more than 800 individuals who 
have been boosted with MVA expressing malaria antigens following ChAd63 prime can be used 
to predict the adverse event profile expected following vaccination with MVA PvDBP in this 
study. 
At the planned dose (2 x 108 pfu), it is expected that the majority of injection site reactions will 
be of mild severity. Injection site pain would be expected to occur frequently. Less frequent 
adverse events are likely to include erythema, swelling, itching and warmth.  Local AEs are likely 
to be mild in nature and should resolve rapidly, although there is the possibility of moderate to 
severe arm pain in some cases.   
Common systemic adverse events post MVA vectored vaccines include headache, feverishness, 
myalgia, arthralgia, fatigue, and malaise. Generally volunteers report a transient ‘flu-like illness” 
within 24 hours of vaccination with MVA which resolves completely.  It is anticipated that the 
majority of systemic adverse events post MVA will be mild or moderate in intensity and resolve 
within 72 hours, although some transient symptoms of severe intensity may also occur more 
rarely.  
8.5.3 Risk of Infection with Blood Borne Organisms  
This controlled blood-stage challenge will involve a blood transfusion, albeit of very small volume 
relative to standard blood transfusion. As for any transfusion, the risk of transmission of a blood 
borne infection cannot be completely eliminated. However, in order to minimise the risk, 
extensive screening for blood borne infections has been performed in both direct blood donors, 
as well as the initial source patient in Thailand, who provided blood for the mosquito infection by 
direct membrane feeding. For viral infections and syphilis, testing was either serological or by 
nucleic acid amplification methods, in accordance with the Joint UK Blood Transfusion and Tissue 

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Transplantation Services Professional Advisory Committee guidelines. The source patient was 
screened for antibodies to W. bancrofti at the Thai field site.  
In addition, the blood bank has been subjected to direct screening and tested negative for 
bacterial contamination, sterility testing, endotoxin screen and mycoplasma specific culture. 
Plasma derived from the bank has also been screened for blood borne infections, as detailed in 
Section 5.2.6 and has tested negative for all blood-borne infection screens by PCR.  Further to 
this, as outlined in section 5.2.5, volunteers also underwent repeat serological testing for HIV, 
hepatitis B and C, syphilis, HITLV-1 and HTLV-2, 90 days after challenge was undertaken, to 
ensure that no seroconversion from a recently-acquired infection (that may have been 
undetectable around the time of challenge and therefore undetectable in the bank) had occurred 
since the challenge period. All tests remained negative.  
For additional safety assessment of blood-stage CHMI by intravenous injection of this new source 
of cyropreserved, infected erythrocytes, repeat blood-borne viral screening (HIV, hepatitis B and 
C, plus EBV and CMV, if negative at screening) will also be performed for all recipients of the 
inoculum at 96 days post-challenge, assessing for any change in serostatus post-exposure. 
Since both donors have been resident in the UK or continental Europe in countries where Bovine 
Spongiform Encephalopathy (BSE) has been reported, there is a theoretical risk of transmission 
of variant Creutzfeldt Jacob Disease (vCJD) from the inoculum. This risk is reduced by 
leukodepletion, as is practised in UK blood donation, according to the Joint UK Blood Transfusion 
and Tissue Transplantation Services Professional Advisory Committee guidelines. Since universal 
leukodepletion was introduced in the UK in 1999, no cases of transmission of vCJD by transfusion 
have been recorded [127]. The risk of infection is further reduced by the very small size of the 
inoculum. The volume to be transfused for this study will be at least nine hundred times smaller 
than the amount received in typical blood transfusion. Serum from volunteers will be collected 
before and after challenge for storage.  
8.5.4 Plasmodium vivax infection   
Volunteers are likely to develop symptomatic malaria infection following CHMI. Symptoms and 
signs will include feverishness, fever, tachycardia, hypotension, chills, rigors, sweats, headache, 
anorexia, nausea, vomiting, diarrhoea, myalgia, arthralgia, low back pain, thrombocytopenia and 
lymphopenia [122]. Unmonitored and untreated, P. vivax infection can be serious (but rarely 
fatal) and, for this reason, volunteers will be followed up closely post-challenge and only enrolled 
in the study if they are deemed reliable and capable of complying with the intensive follow-up 
schedule. A very small proportion of volunteers in previous P. vivax blood-stage and sporozoite-
stage CHMI studies have temporarily required intravenous fluid therapy for nausea and vomiting 
prior to treatment [27, 114]. If the Investigator judges the volunteer to be unwell enough to 
require intravenous fluids or continuous medical input, they shall be transferred to the John 
Radcliffe Hospital under the care of the NHS Infectious Diseases team until they are well enough 
to be discharged home.  
With regards to the above, it is relevant to note that safety and parasitological data from 128 
malaria-naïve subjects participating in CHMI studies in Oxford and the Netherlands were 
analysed and compared to a report from the US Military Malaria Vaccine Program. The authors 
found that cohorts with a longer prepatent period or a higher peak parasitaemia did not 
consistently show a higher frequency of adverse events [128]. However, these data were on P. 
falciparum challenge, and there is a lot less experience with P. vivax challenge.   

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8.5.5 Medications dispensed to volunteers in course of trial  
(a) Treatment of Plasmodium vivax Infection 
P. vivax malaria infection will be treated with either oral Riamet or oral Malarone. 
Riamet contains 20mg of artemether and 120mg lumefantrine per tablet. 6 doses of 4 tablets 
will be given; the first 4 tablets when treatment is initiated, followed by additional doses after 8, 
24, 36, 48 and 60 hours (window period +/- 1 hour for each dose). If there is a contraindication to 
Riamet, oral Malarone will be used (see SmPC for side effects of, and contraindications to Riamet 
and Malarone). At a minimum, two doses (the first and third doses) of Riamet will be directly 
observed. The first doses will be observed in clinic and the volunteers will not return home until 
they are seen to be tolerating the medication.  
Riamet is generally well tolerated but may cause some side effects. Common side effects include 
headache, dizziness, abdominal pain and loss of appetite, sleeping problems, palpitations, 
nausea, vomiting, diarrhoea, pruritus, skin rash, cough, muscle or joint pain and fatigue. 
Volunteers will be counselled that certain side effects, for example dizziness, may impact on the 
performance of skilled tasks such as driving.  
As Riamet may increase the QT interval, Riamet will not be administered to volunteers at risk for 
QT prolongation. Exclusion criteria for this study will include prolonged QT on baseline ECG, a 
history of long QT syndrome, a family history of congenital QT prolongation or sudden death, 
cardiac arrhythmias, severe heart disease, and a history of hypokalaemia or hypomagnesaemia. 
Volunteers will be advised to avoid grapefruit juice whilst taking Riamet as it can affect the 
bioavailability of the artemether [129]. Riamet is also contraindicated in volunteers using 
concomitant medications affecting the QT interval, and will not be given to these volunteers. 
Concomitant use of Riamet may decrease effectiveness of hormonal contraceptives.  
Women using hormonal contraceptives will be advised to use an effective additional and/or 
alternative method of contraception whilst on Riamet treatment, until the start of the next 
menstruation after treatment. 
Malarone contains 100 mg proguanil hydrochloride and 250 mg atovaquone per tablet. 4 tablets 
will be given once daily for 3 days. The first and second dose, out of three doses of Malarone, will 
be directly observed in clinic. Prior to starting Malarone, volunteers will be screened for drug 
interactions and contraindications (including a serum β-hCG test in female volunteers).  
Malarone is generally well tolerated but may cause some side effects, most commonly headache, 
diarrhoea, nausea, vomiting, stomach pain, dizziness rash, fever, low mood, reduced appetite, 
cough or sleep disturbance.   
(b) Treatment of Symptoms Associated with Malaria 
Volunteers will be dispensed cyclizine and paracetamol for the treatment of symptoms 
associated with malaria unless there are contraindications to these medications. Cyclizine is 
generally well tolerated however there is a risk of an allergic reaction. Other side effects include 
skin rashes or itching, drowsiness, headache, dry mouth nose or throat, blurred vision, 
palpitations, difficulty urinating, constipation, anxiety, insomnia or hallucinations. Rare side 
effects include hypotonia, seizures, dizziness, hypertension, paraesthesia, jaundice, hepatitis, 
confusion or dyskinesias. Participants may be dispensed an appropriate, licensed alternative anti-
emetic to cyclizine if they are unable to take cyclizine. Paracetamol is generally well tolerated 
however it can cause an allergic reaction or rarely pancytopaenia. 

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8.5.6 Risk of reaction to the blood sample  
The donor of the blood used in the inoculum is Blood Group O and Rhesus (Rh) and Kell (K) 
negative. People with Blood Group O negative blood are considered ‘universal donors’, as 
recipients of their blood are unlikely to develop red cell alloantibodies when given much larger 
volumes of blood than is envisaged here. For women of child-bearing potential, transfusion of Rh 
and Kell negative blood is also essential to prevent sensitisation and the future risk of haemolytic 
disease of the newborn. In the case of Kell sensitisation, anti-K may additionally lead to 
suppression of red cell production in the fetus. The maximum volume of blood to be used in this 
study (0.025mL – 0.1mL packed red cells) is much smaller than that given in transfusion of one 
unit packed red cells (470mL). The risk of a transfusion reaction or development of antibodies to 
donor red cells, which may make blood transfusion more difficult in the future, cannot be 
completely excluded but is considered highly unlikely, both because of the small volume of blood 
used and because the blood has been leukodepleted. Nevertheless, the volunteers will be 
monitored for this possibility in the period immediately after the administration of the malaria 
parasite dose. A baseline set of observations (respiratory rate, heart rate, temperature and blood 
pressure) will be taken before the administration of the inoculum. Volunteers will be reviewed 
15 minutes (+/- 5 minutes) and 1 hour (+/- 20 minutes) after receiving the inoculum, with a 
repeat set of observations at each time point, before they are able to leave the CCVTM. The 
serum collected for storage (as described above) could be used to test for antibodies at a later 
date if deemed necessary. 
8.6 
Potential benefits for volunteers 
Volunteers will not benefit directly from participation in this study. However, it is hoped that the 
information gained from this study will contribute to the development of a safe and effective P. 
vivax malaria vaccine regimen. Volunteers will also receive information about their general 
health status. 

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9 RECRUITMENT AND WITHDRAWAL FOR TRIAL VOLUNTEERS 
Volunteers may be recruited by use of an advertisement +/- registration form formally approved 
by the ethics committee(s) and distributed or posted in the following places: 
- 
In public places, including buses and trains, with the agreement of the owner / proprietor. 
- 
In newspapers or other literature for circulation. 
- 
On a website operated by the Investigators’ clinical trials group or with the agreement of 
the owner or operator (including on-line recruitment through our website).  
- 
As a post on a Twitter or Facebook or other similar account owned and operated by the 
Investigators’ clinical trials group. 
- 
By e-mail distribution to a group or list only with the express agreement of the network 
administrator or with equivalent authorisation.    
- 
By email distribution to individuals who have already expressed an interest in taking part 
in any clinical trial at the Oxford Vaccine Centre. 
- 
On stalls or stands at exhibitions or fairs. 
- 
Via presentations (e.g. presentations at lectures or invited seminars). 
- 
Oxford Vaccine Centre databases: We may contact individuals from databases of groups 
within the CCVTM (including the Oxford Vaccine Centre database) of previous trial 
participants who have expressed an interest in receiving information about all future 
studies for which they may be eligible. 
9.1 
Informed consent 
9.1.1 Informed consent 
The information sheet will be made available to the volunteer at least 24 hours prior to the 
screening visit. At the screening visit, the volunteer will be fully informed of all aspects of the 
trial, the potential risks and their obligations. The following will be emphasised: 
 Participation in the study is entirely voluntary. 
 Refusal to participate involves no penalty or loss of medical benefits. 
 The volunteer may withdraw from the study at any time. However if the volunteer has 
undergone CHMI and not completed a course of appropriate antimalarial therapy then 
the volunteer will need to maintain contact with the Investigators for monitoring and 
treatment. 
 The volunteer is free to ask questions at any time to allow him or her to understand the 
purpose of the study and the procedures involved. 
 There is no direct benefit from participating. 
 The volunteer’s GP will be contacted to corroborate their medical history and confirm 
that the volunteer is eligible to take part in the study. Volunteers will only be enrolled in 
the study if written information regarding the volunteer’s medical history is obtained 
from the GP. 
 The volunteer will be registered on the TOPS database (The Overvolunteering Prevention 
System; www.tops.org.uk).  
 Blood samples will be taken and volunteers will undergo a separate, optional consent 
process (under the Oxford Vaccine Centre Biobank protocol) regarding indefinite storage 
of any leftover samples for use in other, ethically approved research.  
The aims of the study and all tests to be carried out will be explained. The volunteer will be given 
the opportunity to ask about details of the trial, and will then have time to consider whether or 
not to participate.  

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9.1.2 Informed consent questionnaire 
If they do decide to participate, volunteers will be asked to complete a questionnaire testing 
their understanding of the trial [95]. This helps to ensure that individuals understand the trial 
sufficiently to give informed consent. Provided the volunteer answers all questions in the 
questionnaire correctly, they will be asked to sign a consent form. A photocopy of the signed 
consent form will be taken and given to the participant to take away and keep and the original 
will be stored in the CRF. These forms will also be signed and dated by the Investigator. 
Volunteers who fail to answer all questions correctly on their first attempt will be allowed to re-
take the questionnaire following further discussion with the Investigator. Provided they 
subsequently answer all questions in the quiz correctly they may then complete the consent 
form and be screened for the trial.  
9.2  Inclusion and exclusion criteria  
9.2.1 Inclusion criteria 
The volunteer must satisfy all the following criteria to be eligible for the study: 
 Healthy adult aged 18 to 45 years.  
 Red blood cells positive for the Duffy antigen/chemokine receptor (DARC). 
 Normal serum levels of Glucose-6-phosphate dehydrogenase (G6PD). 
 Able and willing (in the Investigator’s opinion) to comply with all study requirements. 
 Willing to allow the Investigators to discuss the volunteer’s medical history with their 
General Practitioner. 
 Women only: Must practice continuous effective contraception* for the duration of the 
study 
 Agreement to permanently refrain from blood donation 
 Written informed consent to participate in the trial. 
 Reachable (24/7) by mobile phone during the period between CHMI and completion of all 
antimalarial treatment.  
 Willing to take a curative anti-malarial regimen following CHMI.  
 Willing to reside in Oxford for the duration of the study, until antimalarials have been 
completed. 
 Answer all questions on the informed consent quiz correctly.  
* Female volunteers are required to use an effective form of contraception during the course of 
the study as malaria challenge could pose a serious risk to both maternal health and the unborn 
foetus. 
Acceptable forms of contraception for female volunteers include: 
 Established use of oral, injected or implanted hormonal methods of contraception (an 
additional form of contraception will be required when taking the antimalarial 
medication, as this can interfere with the efficacy of hormonal contraception). 
 Placement of an intrauterine device (IUD) or intrauterine system (IUS). 
 Total abdominal hysterectomy. 
 Male sterilisation, if the vasectomised partner is the sole partner for the subject. 
 True abstinence, when this is in line with the preferred and usual lifestyle of the subject 
(periodic abstinence and withdrawal are not acceptable methods of contraception) 
Barrier methods of contraception (e.g. condom or occlusive cap with spermicide) may be 
used in combination with any of the above forms of contraceptive but will not be considered 

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acceptable if used as the sole method of contraception. However, where 
artemether/lumefantrine (Riamet) is used as the anti-malarial treatment post-diagnosis 
following CHMI, female participants using oral, transdermal or systemic hormonal 
contraceptives must agree to using an additional method of contraception (e.g. barrier 
methods) from the time of commencing the artemether/lumefantrine (Riamet) drug course 
until the next menstrual period. This is to minimise any risk of possible reduced effectiveness 
of hormonal contraceptives during concomitant antimalarial therapy, due to the weak 
induction of cytochrome P450 enzymes resulting from treatment with artemether. 
9.2.2 Exclusion criteria 
The volunteer may not enter the study if any of the following apply: 
 History of clinical malaria (any species). 
 Travel to a clearly malaria endemic locality during the study period or within the 
preceding six months. 
 Current or planned treatment with long-acting immune-modifying drugs at any time 
during the study period (e.g. infliximab).  
 Chronic use of antibiotics with antimalarial effects (e.g. tetracyclines for dermatologic 
patients, trimethoprim-sulfamethoxazole for recurrent urinary tract infections, etc.).  
 Weight less than 50kg, as measured at the screening visit. 
 Receipt of immunoglobulins within the three months prior to planned administration of 
the vaccine candidate.  
 Receipt of blood products (e.g., blood transfusion) at any time in the past. 
 Peripheral venous access unlikely to allow twice daily blood testing (as determined by the 
Investigator). 
 Receipt of an investigational product in the 30 days preceding enrolment, or planned 
receipt during the study period. 
 Receipt of any vaccine in the 30 days preceding enrolment, or planned receipt of any 
other vaccine within 30 days preceding or following each study vaccination, with the 
exception of licensed COVID-19 vaccines, which should not be received within 14 days 
before or 7 days after any study vaccination. 
 Planned receipt of a COVID-19 vaccine between 2 weeks before the day of CHMI until 
completion of antimalarial treatment. 
 Concurrent involvement in another clinical trial or planned involvement during the study 
period. 
 Prior receipt of an investigational vaccine likely to impact on interpretation of the trial 
data or the P. vivax parasite as assessed by the Investigator. 
 History of sickle cell anaemia, sickle cell trait, thalassaemia or thalassaemia trait or any 
haematological condition that could affect susceptibility to malaria infection.  
 Any confirmed or suspected immunosuppressive or immunodeficient state, including HIV 
infection; asplenia; recurrent, severe infections and chronic (more than 14 days) 
immunosuppressant medication within the past 6 months (inhaled and topical steroids 
are allowed). 
 History of allergic disease or reactions likely to be exacerbated by any component of the 
vaccine e.g. egg products, Kathon, aminoglycosides. 
 History of allergic disease or reactions likely to be exacerbated by malaria infection. 
 History of clinically significant contact dermatitis. 
 Any history of anaphylaxis in reaction to vaccinations. 
 Pregnancy, lactation or intention to become pregnant during the study. 

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 Use of medications known to cause prolongation of the QT interval and existing 
contraindication to the use of Malarone. 
 Use of medications known to have a potentially clinically significant interaction with 
Riamet and Malarone. 
 Any clinical condition known to prolong the QT interval. 
 History of cardiac arrhythmia, including clinically relevant bradycardia. 
 Disturbances of electrolyte balance, e.g. hypokalaemia or hypomagnesaemia. 
 Family history of congenital QT prolongation or sudden death. 
 Contraindications to the use of both of the proposed anti-malarial medications; Riamet 
Malarone. 
 History of cancer (except basal cell carcinoma of the skin and cervical carcinoma in situ). 
 History of serious psychiatric condition that may affect participation in the study. 
 Any other serious chronic illness requiring hospital specialist supervision. 
 Suspected or known current alcohol abuse as defined by an alcohol intake of greater than 
25 standard UK units every week. 
 Suspected or known injecting drug abuse in the 5 years preceding enrolment. 
 Hepatitis B surface antigen (HBsAg) detected in serum. 
 Seropositive for hepatitis C virus (antibodies to HCV) at screening or (unless has taken 
part in a prior hepatitis C vaccine study with confirmed negative HCV antibodies prior to 
participation in that study, and negative HCV RNA PCR at screening for this study). 
 Positive family history in both 1st AND 2nd degree relatives < 50 years old for cardiac 
disease. 
 Volunteers unable to be closely followed for social, geographic or psychological reasons. 
 Any clinically significant abnormal finding on biochemistry or haematology blood tests, 
urinalysis or clinical examination. In the event of abnormal test results, confirmatory 
repeat tests will be requested. Procedures for identifying laboratory values meeting 
exclusion criteria are shown in SOP VC027.  
 Any other significant disease, disorder, or finding which may significantly increase the risk 
to the volunteer because of participation in the study, affect the ability of the volunteer 
to participate in the study or impair interpretation of the study data. 
 Inability of the study team to contact the volunteer’s GP to confirm medical history and 
safety to participate. 
9.2.3 Prevention of ‘Over Volunteering’ 
Volunteers will be excluded from the study if they are concurrently involved in another trial. In 
order to check this, volunteers will be asked to provide their National Insurance or Passport 
number (if they are not entitled to a NI number) and will be registered on a national database of 
participants in clinical trials (www.tops.org.uk). 
9.2.4 Vaccination and re-vaccination exclusion criteria 
The following adverse events constitute contraindications to administration of vaccine at that 
point in time; if any one of these adverse events occurs at the time scheduled for vaccination, 
the subject may be vaccinated at a later date, or withdrawn at the discretion of the Investigator. 
The subject must be followed until resolution of the event as with any adverse event:  
 Acute disease at the time of vaccination. (Acute disease is defined as the presence of a 
moderate or severe illness with or without fever). All vaccines can be administered to 
persons with a minor illness such as diarrhoea, mild upper respiratory infection with or 
without low-grade febrile illness, i.e. temperature of ≤37.5°C/99.5°F.  

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 Temperature of >37.5°C (99.5°F) at the time of vaccination.  
 Current COVID-19 infection, defined as ongoing symptoms with positive COVID-19 PCR 
swab test taken during current illness or positive COVID-19 PCR swab test within 
preceding 14 days without symptoms. Vaccinations will be delayed by a minimum of 2 
weeks from the date of the 1st positive COVID-19 PCR swab, as long as symptoms are 
improving or resolved. It will be at the discretion of the Investigator to withdraw a 
participant if they develop severe COVID-19 disease.  
The following adverse events associated with vaccine immunisation constitute absolute 
contraindications to further administration of vaccine. If any of these events occur during the 
study, the subject must be withdrawn and followed until resolution of the event, as with any 
adverse event:  
 Anaphylactic reaction following administration of vaccine  
 Pregnancy  
9.2.5 Exclusion criteria on day of CHMI 
 Use of systemic antibiotics with known antimalarial activity within 30 days of CHMI (e.g. 
trimethoprim-sulfamethoxazole, doxycycline, tetracycline, clindamycin, erythromycin, 
fluoroquinolones and azithromycin). 
 Use of anti-malarials within 30 days of CHMI 
The following constitute absolute contraindications to CHMI: 
 Acute disease, defined as moderate or severe illness with or without fever 
 Current COVID-19 infection, defined as ongoing symptoms with positive COVID-19 PCR 
swab test taken during current illness or positive COVID-19 PCR swab test within 
preceding 14 days without symptoms. 
 Pregnancy 
9.2.6 Concomitant medications 
As set out by the exclusion criteria, volunteers may not enter the study if they have received or 
there is planned receipt of any other vaccine within 30 days of each study vaccination, with the 
exception of licensed COVID-19 vaccines, which should not be received between 14 days before 
to 7 days after any study vaccinations. In addition volunteers who are due to receive a COVID-19 
vaccine between 2 weeks before the day of CHMI until expected completion of antimalarial 
treatment (around 2 to 3 weeks after day of challenge based on experience in previous P. vivax 
CHMI studies to date) will not be enrolled in this trial. If a volunteer receives an appointment for 
COVID-19 vaccination after they have undergone malaria challenge but before reaching malaria 
diagnosis criteria, they will be advised to delay their COVID-19 vaccination until after reaching 
malaria diagnostic criteria and completion of antimalarial treatment. If a participant does not 
wish to delay their COVID-19 vaccination, they will be treated with antimalarial treatment at that 
timepoint and withdrawn from the study but will be encouraged to complete follow-up for 
safety. 
Volunteers may also not enter the study if they have any investigational product within 30 days 
prior to enrolment or if receipt is planned during the study period, or any immunosuppressant 
medication within 6 months prior to enrolment or if receipt is planned at any time during the 
study period (inhaled and topical steroids are permitted). Volunteers will be excluded from 
partaking in CHMI, if there is any concomitant use of systemic antibiotics with known anti-
malarial activity or anti-malarial medication within 30 days of CHMI, however, follow-up will 
continue until approximately 6 months (C+96), according to the schedule as for back-up 

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volunteers as long as valid informed consent remains in place. Following CHMI, should a 
volunteer require treatment with systemic antibiotics at any time prior to reaching criteria for 
diagnosis, (as described in Section 11.4), the volunteer will be withdrawn from the study and 
treatment with an appropriate, curative course of anti-malarial therapy will be commenced 
immediately. Follow-up for safety will be continued until 96 days after challenge (C+96) in all 
cases except where there is complete withdrawal of consent.  
9.3 
Withdrawal of volunteers 
In accordance with the principles of the most recent revision of the Declaration of Helsinki (2013) 
and any other applicable regulations, a volunteer has the right to withdraw from the study at any 
time and for any reason, and is not obliged to give his or her reasons for doing so. In addition the 
volunteer may withdraw/be withdrawn from further study procedures at any time in the 
interests of the volunteer’s health and well-being, or for any of the following reasons: 
 Administrative decision by the Investigator. 
 Ineligibility (either arising during the study or retrospectively, having been overlooked at 
screening). 
 Significant protocol deviation. 
 Volunteer non-compliance with study requirements. 
 Incorrect answers to screening questionnaire at the second attempt upon re-screening 
for either second or third CHMI 
 An AE, which requires discontinuation of the study involvement or results in inability to 
continue to comply with study procedures. 
The Local Safety Monitor (LSM) may recommend withdrawal of volunteers. The reason for 
withdrawal from further study procedures will be recorded in the CRF. If a volunteer withdraws 
after having completed a course of antimalarials, as much continued safety data collection as 
possible, including procedures such as safety bloods, will be continued, with agreement of the 
volunteer. For all AEs, appropriate follow-up visits or medical care will be arranged, with the 
agreement of the volunteer, until the AE has resolved, stabilised or a non-trial related causality 
has been assigned.  
Any volunteer who fails to attend for two or more follow-up visits will be deemed to have 
withdrawn from the study. If a volunteer withdraws from the study after CHMI but before 
reaching the criterion for malaria diagnosis, a complete, appropriate, curative course of anti-
malarial therapy must be completed. The importance of this will be emphasised to volunteers at 
screening. If a volunteer refuses to take anti-malarial therapy after malaria diagnosis, a rapid 
assessment of mental state and capacity will be undertaken, with the involvement of NHS 
psychiatric and infectious diseases services. If necessary the volunteer may be detained under 
section 4 of the UK Mental Health Act until this assessment can be carried out. 
If a volunteer withdraws from the study, blood samples collected before their withdrawal from 
the trial will be used/stored unless the volunteer specifically requests otherwise. Similarly, all 
data collected up to the point of withdrawal will be stored, unless they specifically request for it 
to be destroyed. Volunteers are free to request that their blood samples be destroyed anytime 
during or after the study.  
In all cases of subject withdrawal, excepting those of complete consent withdrawal, safety data 
collection will continue until 90 days after challenge (C+90), if subjects have undergone CHMI. 

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9.4 
Pregnancy 
Should a volunteer become pregnant during the trial, she will be treated with antimalarials 
immediately and will be withdrawn from the study. We will not routinely perform venepuncture 
on such volunteers, other than blood films to check that the parasitaemia has been cleared by 
the antimalarials. Additionally, if a volunteer who had been negative for CMV IgG antibodies at 
screening should become pregnant during the study, given the theoretical risk of CMV infection 
from exposure to the inoculum, venepuncture would also be performed to check CMV 
serostatus. With the volunteer’s permission she shall be followed up until pregnancy outcome. 
The management of any volunteer found to be pregnant at any time after challenge up to the 
point of malaria treatment will be discussed with the on-call infectious diseases consultant at the 
Oxford University Hospitals NHS Foundation Trust, including advice on antimalarial drug choice. 
Should a volunteer become pregnant after receiving antimalarial treatment (but prior to the end 
of the study), they shall be withdrawn from the study as soon as we have confirmed that their 
parasitaemia has cleared. With the volunteer’s permission, she shall then be followed up until 
pregnancy outcome. 

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10 CONTROLLED BLOOD-STAGE MALARIA INFECTION INOCULUM 
10.1 Preparation of the inoculum 
Thawing and washing of the inoculum will be done with commercial solutions for human use and 
with disposable syringes and needles according to standard operating procedures used in 
previous studies at Oxford [130, 131]. Work will be carried out in the derogated category III 
laboratory at the Jenner Institute, Old Road Campus Research Building (ORCRB) or New 
Biochemistry Building. Sample manipulations will be performed within a safety cabinet that has 
been fumigated, sterilised and dedicated for this purpose.  
All procedures relating to thawing of the blood inoculum and preparation of the syringes, will be 
performed in accordance with local standard operating procedures.   
10.2 Administration of the inoculum 
The inoculation will take place in Oxford at the CCVTM and according to local Standard Operating 
Procedure. In brief, the inoculum will be administered, at a 1:10 dilution, by intravenous injection 
into an indwelling intravenous cannula. Parasitised red blood cells will be reconstituted in 0.9% 
saline, to a total volume of 5mL. The reconstituted inoculum will be injected via an indwelling 
cannula, followed by a saline flush. Subjects will be observed for a minimum of one hour before 
discharge. All volunteers will receive the inoculum within a maximum of 4 hours of removal from 
frozen storage. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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11 TREATMENT OF TRIAL VOLUNTEERS 
This section describes the clinical procedures for evaluating study participants and follow-up 
after CHMI. All participants (including back-up volunteers) will be required to attend all visits up 
to the point of malaria challenge. Back-up volunteers also must be available on the morning of 
the malaria challenge, in case one of the volunteers withdraws at the last minute. This means 
that confirmation of whether or not a back-up volunteer will be needed for the challenge will not 
be made until the day of challenge (one of the Investigators will call the back-up volunteer that 
morning to confirm either way).  
11.1 Trial sites 
Volunteers will be recruited and undergo all visits at the CCVTM, Oxford, this is inclusive of 
screening, vaccinations and follow-up visits, CHMI and post-CHMI follow-up.  Following CHMI 
until completion of anti-malarial therapy, all volunteers will reside in Oxford. After completion of 
treatment, volunteers may reside outside the Oxford area but will attend for later follow-up 
visits at the CCVTM, Oxford.  
11.2 Study procedures 
Procedures will be performed at the time points indicated in the schedule of procedures (tables 
7-14). Additional procedures or laboratory tests may be performed, at the discretion of the 
Investigators if clinically necessary (e.g. urine microscopy in the event of positive urinalysis).  
11.2.1 Observations 
Pulse, blood pressure and temperature will be measured at the time points indicated in the 
schedule of procedures (Tables 7-14). Weight and height will be measured at screening and 
weight re-measured at the C-2 visit.  
11.2.2 Blood tests 
Blood will be drawn at the time points indicated in the schedule of procedures (Tables 7-14) and 
the following laboratory assays performed: 
At Oxford University Hospitals NHS Foundation Trust, using NHS standard procedures 
 Haematology; Full blood count, to include reticulocyte count at C-2 visit. Duffy 
antigen/chemokine receptor (DARC) gene positivity (either or both Fya/Fyb positive), and 
glucose-6-phosphate dehydrogenase (G6PD) levels and a haemoglobinopathy screen will 
be performed at screening only.  
 Biochemistry; Sodium, potassium, urea, creatinine, albumin, liver function tests, 
magnesium and calcium, however magnesium and calcium will only be measured at 
screening. Serum will also be tested for beta-human chorionic gonadotrophin (β-HCG) at 
C-2, C+7, C+14, C+21 and C+28/day of malaria diagnosis. For Group 2 and 3 participants 
only, C-reactive protein (CRP) will be measured on vaccination day and days 1, 3 and 7 
after each vaccination as an exploratory measure only (CRP results will not be included in 
safety analysis). 
 Diagnostic serology; HBsAg, HCV antibodies, HIV antibodies, CMV antibodies and EBV 
antibodies will be performed at screening. 
 Immunology; Human Leukocyte Antigen (HLA) typing at enrolment (D0). 
At the University of Oxford research research laboratories (at the Jenner Institute and 
Department of Biochemistry) 

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 Diagnostic Tests: Blood films for malaria parasites and PCR for P. vivax DNA and 
gametocytes. 
 Immunology: Immunological responses to primary P. vivax infection will be assessed by a 
variety of established and exploratory assays. This may include: 
o Antibodies and B cell responses to the P. vivax Duffy-binding protein (PvDBP) – 
total IgG, isotypes and avidity; 
o T cell responses to PvDBP by ex-vivo ELISpot and flow cytometry assays; 
o Functional antibody assays against parasites in vitro;  
o Antibody responses to whole parasites and other P. vivax antigens including red 
blood cell invasion ligands as well as the use of arrays; 
o Serum cytokine analysis. 
o B cells, plasma and/or serum may be analysed and used to produce human 
monoclonal antibodies against P. vivax malaria. 
 Genetic tests: DNA analysis of genetic polymorphisms potentially relevant to 
immunological responses and gene expression studies of the host and the parasite 
amongst others may be performed at the discretion of the Investigators. 
 COVID-19 serology: Antibody to SARS-COV-2 will be measured at screening, re-screening 
and at the final study visit following the final CHMI for each participant (+/- at interim 
time points retrospectively) for restrospective exploratory analysis of any association 
between vaccine immunogenicity and COVID-19 serostatus 
 Samples may be sent to collaborating laboratories for other immunological assays or 
studies of malaria. 
 Samples may also be sent to collaborating laboratories within and outside the UK for 
immunomonitoring and/or harmonisation of key immunological assays and/or studies of 
malaria. 
Immunological assays will be conducted according to the procedures established in the test 
laboratories. Specific details of which immunological tests will be performed at each time-point 
are detailed in the separate immunomonitoring plan – this will also clearly state which assays are 
conducted to meet the trial’s primary objectives and which are exploratory. With the volunteers’ 
informed consent, any leftover cells, plasma, serum, whole blood (or their purified components) 
will be registered under University of Oxford HTA licence 12217 and stored indefinitely for future 
analysis of human malaria infection. This may include human DNA and RNA analysis. If a subject 
elects not to permit this, all of that subject’s leftover samples will be discarded after the required 
period of storage to meet Good Clinical Practice (GCP) and regulatory requirements. 
11.2.3  Urinalysis 
Urine will be tested for the presence of clinically significant proteinuria, glycosuria or haematuria 
(as defined in Appendix A) at the screening and re-screening visits. For female volunteers only, 
urine will be tested for beta-human chorionic gonadotrophin (β-HCG) at screening, immediately 
prior to each vaccination, at days 0 and 56 and on the day of diagnosis, immediately prior to 
initiation of treatment.  
11.2.4  Electrocardiogram 
An electrocardiogram will be performed at the initial screening visit for detection of any 
conduction abnormalities, including long QT syndrome. 

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11.2.5 Vaccinations  
Before each vaccination, the on-going eligibility of the volunteer will be reviewed. The vaccine 
will be administered as described above in section 6.4. The injection site will be covered with a 
sterile dressing and the volunteer will stay in the local trial site for observation for 1 hour, in case 
of immediate adverse events. Observations will be taken 30 minutes after vaccination (+/- 5 
minutes) and the sterile dressing removed and injection site inspected. Observations will also be 
taken at 60 minutes after vaccination (+/- 10 minutes).  
An oral thermometer and tape measure will be given to each volunteer, with instructions on use, 
along with the emergency 24 hour telephone number to contact the on-call study physician if 
needed.  
All Group 1 volunteers may be vaccinated on the same day, or within the windows as described 
in Table 7. All Group 1 volunteers will subsequently be challenged, via intravenous administration 
of the challenge inoculum, on the same day. 
Pending satisfactory review of safety data following the completion of CHMI of at least 2/3 
Group 1 volunteers (as defined by 6 days post completion of anti-malarial treatment and follow-
up until at least C+ 28), all volunteers in Group 2 may be vaccinated on the same day, or within 
the windows as described in Table 7. All Group 2 volunteers will subsequently be challenged, via 
intravenous administration of the challenge inoculum. This may occur on the same day for all 
volunteers or split over 2 consecutive days if practically more feasible for the clinic and/or 
laboratory. 
11.2.6 Management of post-vaccination fevers 
Post-vaccination fevers may cause diagnostic uncertainty and concurrent COVID-19 infection 
could be a possibility. Data from this and previous studies with ChAd63 PvDBP and MVA PvDBP 
show that post-vaccination fever does occur in a small proportion of participants. Following 
vaccination with ChAd63 PvDBP, less than 10% of volunteers developed a recorded fever, 
however subjective feeling of feverishness was more common. Similarly fever post vaccinations 
with MVA PvDBP was uncommon but feelings of feverishness occurred in more than half of the 
vaccinees [84]. 
If a participant develops a fever within the first 24 hours after vaccination and no other 
symptoms associated with COVID-19 disease (new onset cough, anosmia or ageusia), then post-
vaccination fever is most likely. Participant will be advised to self-isolate until they become 
afebrile for 24 hours. Participants will be requested to attend their day 1 post vaccination study 
visit to allow collection of study samples including safety blood tests. This study visit will be 
conducted in a side room with study staff wearing appropriate PPE and participants will be asked 
to attend the visit by means other than public transport.  
If a participant develops a fever post vaccination, which is associated with either new onset 
cough or anosmia or ageusia, they will be advised to self-isolate as per Public Health England 
(PHE) guidance and directed to local community based COVID-19 testing. If participants remain 
febrile more than 48 hours post vaccination, they will be advised to continue self-isolation and 
directed to local community based COVID-19 testing. Whilst awaiting their COVID-19 PCR test 
results, participants will be advised not to attend the clinic for study visits. 
If a participant tests positive for COVID-19 or whilst awaiting their COVID-19 test result, they will 
be advised to continue self-isolation as per PHE guidance. Any study visits which are due whilst a 
participant is self-isolating, should be rescheduled to occur when self-isolation ends, if this falls 
within the visit window. If a participant remains in self-isolation during the period of the visit 

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window, then the study visit will be conducted by telephone and no blood tests will be taken. 
Study visit windows have been increased in order to accommodate these scenarios. 
If a participant is self-isolating for a prolonged period post-vaccination (for example because they 
are a household contact of a suspected or confirmed COVID-19 case) and hence would miss all 
three initial post vaccination visits, then it will be at the Investigator’s discretion to conduct these 
as physical visits at CCVTM to allow full assessment including blood tests. These study visits will 
be conducted in a side room with study staff wearing Personal Protective Equipment (PPE). 
If a participant tests negative for COVID-19, they can stop self-isolating and continue with study 
visits as planned. 
11.2.7 Diary card 
Following each vaccination, volunteers will be asked to complete a diary card which may be in 
paper or electronic form. Volunteers will be asked about foreseeable local and systemic AEs for 7 
days (solicited AEs). After this, volunteers will be asked to record any AE daily, for 28 days 
(unsolicited AEs). Diary cards will be reviewed with volunteers at each post-vaccination clinic 
visit.  
11.2.8 SARS-COV-2 PCR swab 
Whilst the COVID-19 pandemic is ongoing, a combined nasopharyngeal and throat swab will be 
tested for SARS-COV-2 by PCR two days before malaria challenge (C-2) in all volunteers. A 
positive SARS-COV-2 swab, even if the participant is asymptomatic, will be a contra-indication to 
proceeding to CHMI. All participants who undergo CHMI will also have a COVID-19 swab taken on 
the day of malaria diagnosis when malaria treatment is commenced. Any participant who 
develops symptoms, which may be consistent with COVID-19 disease after undergoing malaria 
challenge and prior to commencing malaria treatment, may also undergo testing for COVID-19 by 
PCR swab. Swabs from symptomatic participants will be taken by the study team in-house but in 
a physically separate location from the main clinic area with separate access, with full infection 
control precautions (as per the PPE SOP). 
If a participant develops symptoms consistent with COVID-19 after completing malaria 
treatment, they will be referred to local community testing for COVID-19.  
11.3 Study visits  
All clinical reviews and procedures will be undertaken by one of the clinical team. The procedures 
to be included in each visit are documented in Tables 7-14. Each review is assigned a time point 
and a window period within which the review will be conducted. 
11.3.1 Screening visits  
Where possible, and where consent to contact by telephone has been provided by email, 
individuals may be phoned by a member of the clinical team to discuss the study, prior to the 
screening visit. This pre-screening telephone call will provide an opportunity for interested 
individuals to discuss the study, eligibility criteria and study requirements. Where a pre-screening 
call takes place, if individuals continue to express an interest in taking part in the trial following 
the pre-screening call, a screening visit will be scheduled.  
Screening visits may take place up to 90 days, prior to enrolment. Informed consent will be 
gained at screening. If consent is given, the screening procedures indicated in the schedule of 
procedures (Table 7) will be undertaken, including testing for Duffy antigen/chemokine 
receptor (DARC) positivity, G6PD levels and haemoglobinopathy screen.  

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The subject’s general practitioner will be contacted with the written permission of the subject 
after screening to ascertain any significant medical history and as notification that the subject 
has volunteered for the study. During the screening the volunteers will be asked to provide their 
National Insurance or passport number so that this can be entered on to a national database 
which helps prevent volunteers from participating in more than one clinical trial simultaneously 
or over-volunteering for clinical trials (www.tops.org.uk). 
Abnormal clinical findings from the medical history, physical examination, urine or blood tests at 
any point in the study will be assessed according to the scales in Appendix A and site specific 
laboratory adverse event grading tables kept in the trial master file (ref: SOP VC027). If a test is 
deemed clinically significant it may be repeated to ensure it is not a single occurrence. If an 
abnormal finding is deemed to be clinically significant, the volunteer will be informed and 
appropriate medical care arranged with the permission of the volunteer. Exclusion of the 
volunteer from enrolling in the trial or withdrawal of a volunteer from the trial will be at the 
discretion of the Investigator. 
Where more than 90 days has lapsed between the initial screening visit and date of enrolment, a 
re-screening visit will be conducted to ascertain if there have been any changes in the medical 
history, medical examination findings or urinalysis, haematology or biochemistry blood tests 
only. Other blood tests and ECG will not be repeated routinely. In addition, where a reply from 
the subject’s GP has already been received, the GP will not be re-contacted unless there is any 
need to obtain further information where appropriate (e.g. regarding a new medical event or 
finding) and at the discretion of the Investigator.  
Participants who are currently enrolled in Group 2 and consent to continue in the study, will 
attend a re-screening visit prior to their next vaccination due to the long duration of the trial halt. 
11.3.2 Enrolment and first vaccination with ChAd63 PvDBP (D0) 
The eligibility of the volunteer will be reviewed at the end of the screening visit and again when 
all results from the screening visit have been considered. If eligible, a day 0 visit will be scheduled 
for the volunteer to receive the first dose of vaccine and be enrolled in the trial.  
At the day 0 visit, any new medical issues or symptoms that have arisen will be assessed. Physical 
observations, urinary β HCG test in female volunteers and venepuncture for immunology and 
safety bloods will be undertaken according to Table 7. The inclusion and exclusion criteria for the 
study will be reviewed. If the volunteer remains eligible and there are no contraindications to 
vaccination, the ChAd63 PvDBP vaccine will be administered as described in section 6.4 and the 
visit carried out as described in above Section 11.2.5.  
11.3.3 Group 2 only - second vaccination with ChAd63 PvDBP (PB0) 
For Group 2 volunteers the second vaccination with ChAd63 PvDBP will occur 12-18 months after 
the first vaccination. The second vaccination visit will be referred to as Post-Boost day 0 ‘PB0’. 
The same procedures as for a day 0 visit will be performed at the PB0 visit. 
11.3.4 Reviews post-vaccination on days 1, 3, 7, 14 and 28 (or PB1, PB3, PB7, PB14 and PB28 for 
Group 2) 
On subsequent visits, the volunteers will be assessed for local and systemic adverse events, using 
a diary card, interim history, physical examination and blood tests at the time points indicated in 
the schedule of attendances (Table 7). Blood will also be taken for exploratory immunology 
analysis.  

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Volunteers will be asked to record all AEs via the diary card and upon attending clinic visit on 
days 1, 3 and 7, during which diary cards will be reviewed with volunteers. Volunteers will be 
asked directly about foreseeable local and systemic AEs for 7 days (solicited AEs). Volunteers will 
be asked about any new symptoms from day 7 until day 28, on a daily basis via the diary but will 
not be asked directly about foreseeable symptoms. Diary cards will be reviewed for details of 
solicited and unsolicited AEs for 28 days after each vaccination, and any new or undocumented 
medical issues or symptoms that have arisen will be assessed. Physical observations and 
venepuncture for immunology and safety bloods will be undertaken according to Table 7.  
11.3.5 Vaccination with MVA PvDBP (day 56 or PB56 for Group 2) 
This visit will include a follow up visit for the ChAd63 PvDBP vaccination and administration of 
the MVA PvDBP vaccine. Any new medical issues or symptoms that have arisen will be assessed. 
Physical observations, urinary β HCG test in female volunteers and venepuncture for 
immunology and safety bloods will be undertaken according to Table 7. The inclusion and 
exclusion criteria for the study will be reviewed. If the volunteer remains eligible and there are 
no contraindications to vaccination, the MVA PvDBP vaccine will be administered intramuscularly 
in the opposite arm to that used for the first vaccination and as described in sections 6.4 and 
11.2.5.  
11.3.6 Reviews post-vaccination on days 57, 59, 63, and 70 (or PB57, PB59, PB63 and PB70 for 
Group 2) 
On subsequent visits, the volunteers will be assessed for local and systemic adverse events, using 
a diary card, interim history, physical examination and blood tests at the time points indicated in 
the schedule of attendances (Table 7). Blood will also be taken for exploratory immunology 
analysis.  
Volunteers will be asked to record all AEs via the diary card and at visits on days 1, 3 and 7 post 
vaccination, during which diary cards will be reviewed with volunteers. Volunteers will be asked 
directly about foreseeable local and systemic AEs for 7 days (solicited AEs). Volunteers will be 
asked to continue to record any new symptoms from day 7 until day 28, on a daily basis via the 
diary but will not be asked directly about foreseeable symptoms. Diary cards will be reviewed for 
details of solicited and unsolicited AEs for 28 days after each vaccination, and any new or 
undocumented medical issues or symptoms that have arisen will be assessed. Physical 
observations and venepuncture for immunology and safety bloods will be undertaken according 
to Table 7.  
11.3.7 Two days before CHMI (C-2 (±1))  
This visit will include a follow up visit for the MVA PvDBP vaccination, as well as assessment for 
eligibility for CHMI. Any new medical issues or symptoms that have arisen will be assessed. 
Physical observations, serum β-HCG test in female volunteers and venepuncture for immunology, 
malaria PCR and safety bloods will be undertaken (according to Table 8 for Group 1; Table 12 for 
Groups 2 and 3). A combined nasopharyngeal and throat swab for SARS-COV-2 PCR will also be 
taken. Results of safety bloods and the SARS-COV-2 PCR test taken at this visit must be available 
and reviewed prior to challenge. Any participant with a positive SARS-COV-2 PCR swab will not 
proceed to CHMI. 
11.3.8 Day of CHMI (C0)  
CHMI will be administered, according local standard operating procedure (SOP), this will include 

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 Interim history and examination of the injection site and any body systems felt to be 
necessary by the Investigator and verify continuing eligibility / contraindications. 
 Baseline physical observations (respiratory rate, pulse, blood pressure and temperature). 
 Intravenous access via cannulation in forearm vein, flushed with normal saline. 
 For each volunteer the inoculum must be injected within 4 hours of the inoculum being 
thawed, followed by a further normal saline flush. 
 Physical observations will be repeated at 15 minutes (+/- 5 minutes) post-administration 
of the inoculum and again at 1 hour (+/- 20 minutes), in order to assess for immediate 
adverse reactions, with regular visual observation throughout [132]. If the volunteer 
should show signs or symptoms of a transfusion reaction, observations will be repeated 
and the volunteer will be medically reviewed by a physician. 
 Volunteers will observed for at least 60 minutes, however, this period may be extended if 
there are any clinical concerns.  
 If there have been no symptoms or signs indicative of a transfusion reaction, the cannula 
will be removed after 1 hour  
Before leaving CCVTM, volunteers will be informed about the unlikely possibility of a delayed 
transfusion reaction and will be provided with the 24 hour emergency mobile telephone number, 
to enable them to contact a physician in the event of concern. 
A Medic-Alert type card will be issued to each volunteer. This will contain the study physician 
contact details and a request that the research team be contacted immediately in the event of 
illness/accident. Each subject will also be issued with an accurate oral thermometer. If the 
subject does not have their own mobile telephone they will be issued with one for the duration 
of the study, and counselled about the importance of keeping it switched on or checking the 
messages regularly. In addition full contact details for each subject will be documented, including 
home and work addresses, home and work landline telephone numbers where available and 
next-of-kin address and telephone numbers. Mobile telephone numbers will be verified prior to 
challenge to ensure the volunteers are easily contactable. Subjects must also provide the 
Investigators with the name and 24 hour telephone number of a close friend, relative or 
housemate who will be kept informed of their whereabouts for the duration of the study.  
Volunteers must be resident in Oxford / the surrounding area until they have had a least one 
negative thick blood film, and (/or, if not diagnosed on the basis of blood-film) two consecutive 
qPCR results with substantial reduction in genome copies/mL after commencing antimalarial 
treatment. If volunteers do not reach malaria diagnosis, they must remain in the Oxford area 
until they have completed anti-malarial treatment. 
Volunteers will be counselled that should they fail to return for treatment having been infected 
with P. vivax malaria they could become very unwell and potentially die. They will be informed 
that should they fail to attend a scheduled clinic visit post-challenge, their nominated contact, 
next of kin and the police may be informed and a search started.  
11.3.9 Days 1-6 post-CHMI (C+1 – C+6) 
In the VAC069 study, three doses of inoculum were assessed for feasibility of infection. Two 
volunteers received the equivalent of a whole vial of infected erythrocytes, two further 
volunteers received a 1:5 dilution and two received a 1:20 dilution. All volunteers were 
completely asymptomatic in the first 6 days. Patent parasitaemia, as determined by qPCR, was 
first detected after day 7, in a volunteer who had received the highest dose. For the same 
volunteer, microscopic patency was at day 12 and diagnosis was made on the same day (C+12.5). 
For the remaining volunteers, qPCR became positive after day 8 and microscopic patency was no 

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earlier than day 14. Diagnostic criteria for all remaining volunteers was reached between days 15 
and 16. Therefore, given a 1:10 dilution is to be used in this study, qPCR parasitaemia patency is 
not expected until at least 7 days after challenge and so volunteers will not need to be reviewed 
in clinic until day 7.  However, they will be phoned daily by the clinic team during this period to 
make sure they are well and contactable, and will be able to contact the study physicians on the 
24 hour emergency telephone number if needed.  
11.3.10 Days 7-28 post-CHMI (C+7 – C+28) (Group 1 only) 
Volunteers will be reviewed in clinic once in the morning of day 7 after challenge until day 9, 
then twice daily from day 10 until diagnosed, or if diagnosis criteria is not met, day 28 post-
challenge inclusive (C+10-C+28). However, from day 21 after challenge, visits may be reduced to 
once daily at the discretion of the Investigator (as agreed by the Chief Investigator) e.g., if qPCR is 
very low or undetectable, and volunteer is completely asymptomatic (qPCR results may be 
unblinded for this purpose). 
At each follow-up visit: 
 Physical observations will be performed. Venepuncture will be performed as per schedule 
of attendance (Table 8, 9, 10 and 11), including blood for assessing parasite growth rate, 
immune response and level of gametocytaemia.  
 Volunteers will be questioned as to whether they have; 
o Experienced any of the foreseeable symptoms of malaria. 
o Experienced any other symptoms.  
o Taken any medications including over the counter medications. 
Full physical examination will be performed if deemed necessary by the Investigators. Subjects 
will be encouraged to contact one of the Investigators on the 24 hour emergency mobile 
telephone number if they develop symptoms of malaria or concerning AEs between the regular 
clinic reviews. The severity of symptoms will be assessed using grading criteria summarized in 
Section 10.4. 
Diagnosis will be made according to criteria described in section 9.4 below. If volunteers reach 
day 28 post-challenge (C+28) without reaching diagnostic criteria, they shall be started on anti-
malarial treatment empirically. Subjects will be reviewed in clinic approximately 24 and 48 hours 
after starting anti-malarial therapy, as described in section 9.5.   
If a volunteer is unwell and unable to attend the CCVTM for a visit they will be reviewed on the 
phone and visited at home by one of the Investigators if necessary. Such visits will be conducted 
according to SOP VC022: Lone Working in the Community.  
11.3.11 Days 7-21 post-CHMI (C+7 – C+21) – Groups 2 and 3 
Following review of the results from the recent malaria challenge clinical trials, VAC079 and 
VAC069, the number of visits in the post challenge period for VAC071 has been reduced to 
minimise the number of bleeds and burden on volunteers. The post-challenge visits have also 
been standardized between the two vaccine trials (VAC071 and VAC079) and challenge only trial 
(VAC069) to allow direct comparison between controls and vaccinees. 
Review of the qPCR results and parasite multiplication rate (PMR) modelling from the recent 
CHMI in VAC069C and VAC079 trials has shown that sufficient data can be obtained for accurate 
PMR modelling if bleeds for qPCR continue once a day until qPCR reaches ≥1000 genome 
copies/ml, instead of starting twice a day visits from C+10 onwards. Once qPCR levels reach 
≥1000 genome copies/ml, then visits will increase to twice a day in order to not delay diagnosis 

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as qPCR may reach the diagnostic threshold of ≥5000 genome copies/ml with malaria symptoms 
within about half a day. PMR modelling is also minimally affected if, in addition to reducing the 
frequency of bleeds to once daily, participants are treated at C+21, instead of C+28, even if they 
have not reached malaria diagnostic criteria at that timepoint.  
Group 2 and 3 volunteers will therefore be reviewed in clinic once a day in the mornings from 
day 7 after challenge until day 9. From day 10 after challenge onwards visits continue once a day 
until the participant’s qPCR count reaches ≥1000 genome copies/ml, when visits will increase to 
twice a day. Visits will then continue twice a day until diagnosis, or if diagnosis criteria are not 
met, until day 21 post-challenge inclusive (C+21).  
At each follow-up visit: 
 Physical observations will be performed. Venepuncture will be performed as per schedule 
of attendance (Table 12, 13 and 14), including blood for assessing parasite growth rate, 
immune response and level of gametocytaemia.  
 Volunteers will be questioned as to whether they have: 
o Experienced any of the foreseeable symptoms of malaria. 
o Experienced any other symptoms.  
o Taken any medications including over the counter medications. 
Full physical examination will be performed if deemed necessary by the Investigators. Subjects 
will be encouraged to contact one of the Investigators on the 24 hour emergency mobile 
telephone number if they develop symptoms of malaria or concerning AEs between the regular 
clinic reviews. The severity of symptoms will be assessed using grading criteria summarized in 
Section 12 below. 
Diagnosis will be made according to criteria described in section 11.4 below. If volunteers reach 
day 21 post-challenge (C+21) without meeting diagnostic criteria, they shall be started on anti-
malarial treatment empirically. Subjects will be reviewed in clinic approximately 24 and 72 hours 
after starting anti-malarial therapy as per Table 14 below. 
If a volunteer is unwell and unable to attend the CCVTM for a visit they will be reviewed on the 
phone by a clinician. If inperson assessment is considered necessary, the participant will be 
referred to appropriate NHS services.  
 
11.4 Algorithm for initiation of treatment  
11.4.1 Algorithm for initiation of treatment for Group 1 
Diagnostic criteria will be based on symptoms in-keeping with malarial infection, thick film 
microscopy results and real-time quantitative polymerase chain reaction (qPCR), summarised in 
the algorithm in Figure 6. 
Symptoms or signs that will be considered as indicative of symptomatic malarial infection will be 
fever >37.8oC, rigors or other severe symptoms or signs related to malarial infection, including, 
but not limited to, subjective feverishness, sweats, headache, myalgia, arthralgia, nausea or 
vomiting. 
Microscopy will be performed by one or more experienced microscopists and a positive 
microscopy result will be defined as the detection of at least two morphologically normal malaria 
parasites seen in 200 high-power (1000x) fields. This will be diagnostic in the presence of 
symptoms in-keeping with malaria infection. If the volunteer is asymptomatic, diagnosis will be 

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Page 82 of 128 
based on a combination of microscopy and qPCR results, as detailed below. Further microscopy, 
e.g. thin film microscopy, may also be performed in order to obtain further information on 
parasite life-cycle stage, but these results will not be considered for diagnosis and treatment 
decisions.  
Asexual blood-stage parasitaemia will be measured by qPCR for the P. vivax 18S rRNA gene. In 
the presence of symptoms or a positive thick film in the absence of symptoms, ≥5,000 genome 
copies/mL will be considered diagnostic but a PCR result ≥10,000 copies/mL will be considered 
positive, regardless of symptoms. Real time qPCR for P. vivax will be performed at the same time 
as microscopy, although all Investigators (except the Principal Laboratory Investigator) will be 
blinded to the results. Blinding of PCR operators to the vaccination status of a volunteer (as 
opposed to an infectivity control in the parallel VAC069 study) will be maintained by assigning a 
new unique identifier to the volunteer for PCR samples from the C-1 visit. Following these 
diagnostic parameters, if a positive thick film for malaria parasites is seen in an asymptomatic 
volunteer for the first time, the qPCR results for this volunteer will be un-blinded to the Chief 
Investigator by the Principal Laboratory Investigator and the volunteer treated only if any 
available qPCR result for that individual has been measured as ≥5000 genome copies/mL. If, as 
judged by the investigator, a volunteer develops symptoms in-keeping with malaria, but has a 
negative thick film result, the volunteer will be discussed with the Chief Investigator. If deemed 
appropriate by the Chief Investigator, the qPCR results for this volunteer will be unblinded by the 
Principal Laboratory Investigator and the volunteer treated only if any available qPCR result is 
≥5000 genome copies/mL. At the point that a volunteer has a qPCR result exceeding 10,000 
genome copies/mL, the Principal Laboratory Investigator will unblind the Chief Investigator to 
the result and the volunteer will be treated, regardless of the presence of symptoms.  
The Investigators are able to treat any volunteer for malaria regardless of the thick film 
microscopy or qPCR result if they are clinically concerned (and have discussed the case with the 
Chief Investigator), or a volunteer wishes to withdraw from the study. If necessary, volunteers 
can be discussed with the LSM and/or the infectious diseases consultant on call at the John 
Radcliffe Hospital for further management under the care of the infectious diseases team, 
inclusive of parenteral anti-malarial therapy if deemed appropriate.  

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Figure 6: Algorithm for diagnosis and initiation of treatment in Group 1. N.B. If day 28 after challenge is reached without meeting any diagnostic criteria, 
treatment will be initiated regardless of qPCR or microscopy results, i.e. even if parasitaemia is undetectable. 
Negative 
diagnosis, 
continue 
monitoring 
≥2 parasites 
in 200 fields 
<2 parasites 
in 200 fields 
Positive 
diagnosis, 
begin 
treatment
Positive 
diagnosis, 
begin 
treatment 
Symptomatic 
≥2 parasites 
in 200 fields 
Asymptomatic 
qPCR 
≥5,000 
genome 
copies/mL 
qPCR 
<5,000 
genome 
copies/mL
qPCR 
<10,000 
genome 
copies/mL
qPCR 
≥10,000 
genome 
copies/mL
Positive 
diagnosis, 
begin 
treatment 
Negative 
diagnosis, 
continue 
monitoring 
Positive 
diagnosis, 
begin 
treatment 
<2 parasites 
in 200 fields 
qPCR 
≥5,000 
genome 
copies/mL
qPCR 
<5,000 
genome 
copies/mL

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11.4.2 Algorithm for initiation of treatment for Group 2 and 3 
It is now well established that nucleic acid amplification-based diagnostics have greater 
sensitivity than microscopic methods for detecting malaria infection both in clinical infection and 
in the P. falciparum challenge model. In the latter, qPCR targeting the 18S ribosome DNA target 
has been used as the diagnostic tool, reliably detecting parasitaemia earlier than thick film blood 
smear.  
The qPCR assay that we have used in numerous Oxford-led CHMI P. falciparum challenge studies 
is now qualified and highly sensitive, reliably detecting parasitaemias as low as 20 parasites per 
mL of blood (0.02 parasites per μL), long before clinical symptoms manifest. The qPCR assay has 
also performed well in an international External Quality Assurance (EQA) exercise [133]  
It is also important to note that other trial centres in the USA routinely use PCR as a diagnostic 
tool in CHMI studies. NCT020-15091 was a multi-institution, Phase I, open-label, dose-escalation 
trial with CHMI, designed to assess the safety, immunogenicity, and protective efficacy of PfSPZ 
vaccine and this used PCR as the primary diagnostic [134] 
For P. vivax, we also use a qPCR assay targeting the pan-plasmodium 18S ribosome DNA target. 
The only other centre worldwide that routinely performs blood-stage challenge studies for P. 
vivax (QIMR, Australia), uses PCR as the sole diagnostic tool in CHMI studies, and our qPCR assay 
is based on this, utilising identical primer and probe sequences. In all other aspects, apart from 
the QIMR derived detection sequences and reaction mixture employed, the extraction of DNA 
and qPCR is identical to the existing and formally validated P.falciparum qPCR method employed 
as sole, objective, diagnostic tool in the two P.falciparum trials described below. This pan-
plasmodium qPCR is in the process of undergoing a similar formal validation and work completed 
so far, demonstrates that this is similarly fit for purpose. As examples of qualification parameters 
that contribute to validation, the assay has excellent specificity (within the context of a P.vivax 
only CHMI study), linearity, acceptable accuracy (based on reference samples of microscopically 
quantified P.vivax infected blood), precision and reproducibility (based on several inter-operator 
tests with acceptable %CV values when assessing prepared samples at the described diagnostic 
thresholds in >20 replicates). The assay has an acceptable detection and reliable quantitation 
limit of 50-100 genomes per ml (well below reproducible microscopic detection levels. While 
detection is possible down to approximately 25 genomes per ml as indicated below, it is less 
reproducible at this level). The assay is also extremely robust, with both EDTA whole blood 
samples, extracted DNA and standards remaining stable and giving reproducible qPCR scores at 
4°C storage for many days (which is beyond the intended use for real time qPCR follow up). The 
range of the qPCR is similar to that of the previously validated P.falciparum assay, with at least a 
4 log range from 100 genomes per ml to 1,000,000 for the standards employed (actual range 
used in assays is from 25 to 1,000,000 genome copies per ml). These criteria assessments are in 
accordance with the ICH Harmonised Tripartite Guideline Part II: Validation of Analytical 
Procedures: Methodology, (European Medicines Agency, 2006). This is further supported by data 
from the lab’s participation in the UKNEQAS external quality assurance scheme since mid-2018, 
with 5 rounds of samples assayed in both P.falciparum and P.vivax assays completed to date, 
with a 100% success rate.    
To date, comparative qPCR and microscopy data are available for two blood-stage P. vivax CHMI 
studies conducted with the PvW1 blood inoculum in Oxford; VAC069A&B (n=11 inclusive of 3 
participants who underwent CHMI twice) (NCT03797989) and CHMI of VAC071 Group 1 
participants (n=3) (NCT04009096). Here, the greater sensitivity of qPCR compared to thick film 
microscopy has been consistently demonstrated with 3/14 participants diagnosed by qPCR prior 
to microscopic patency and, where infection was microscopically patent (11/14 participants), 

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Page 85 of 128 
qPCR detected parasitaemia (>25 genome copies/mL) at least 6 days prior to thick film positivity 
(as defined as ≥2 asexual forms seen in 200 high-power fields). At the pre-specified qPCR 
thresholds for diagnosis, as described in Figure 2, 3/14 participants did have a positive thick film 
result prior to reaching diagnostic criteria (≥5,000 genome copies/mL), however, none of these 
three participants had experienced symptoms consistent with the clinical threshold for diagnosis 
at the time of thick smear positivity and were later diagnosed within 1.5 days of microscopic 
patency, without complication. 
Positive thick smear results may result from chance findings, since following blood-stage 
challenge, parasites may be seen on light microscopy at any time-point. Where this occurs, and 
premature diagnosis results, this limits the qPCR dataset available for PMR modelling. Removing 
this possibility, therefore, increases the data available for analysis of the primary outcome 
measure. In addition, use of qPCR as the sole diagnostic tool leads to greater standardisation of 
diagnosis across study groups, permitting improved inter-group as well as inter-trial comparison. 
In Oxford, we have now safely conducted two P. falciparum blood-stage CHMI studies, where 
qPCR is the sole diagnostic method (Clinicaltrials.gov identifiers NCT03906474 and 
NCT02927145). Analysis of the parasitaemia at diagnosis in one of these studies, VAC063B, 
indicates that removal of microscopy as a diagnostic measure, reduced the range over which 
diagnosis was made compared to two prior P. falciparum blood-stage CHMI studies, where 
microscopy was utilised (see Figure 7).  
As microscopy findings are not considered within the primary efficacy analysis for this study, 
microscopy for Group 1 participants was principally utilised as an additional diagnostic tool for 
safety reasons. The data from the two previous P. vivax blood-stage CHMI studies were therefore 
analysed to apply the revised diagnostic criteria retrospectively, to determine if timing of 
diagnosis would have been altered. Using the revised criteria, the majority of diagnoses would 
not have been delayed, although it is estimated 36% of volunteers would have had a small delay 
to diagnosis. However, since clinical criteria remain integral to the diagnostic algorithm, this 
small delay should not result in any increased risk to volunteers, and the ability for investigators 
to treat any participant in the event of clinical concern, following discussion with the CI, 
regardless of parasitaemia, will ensure participant safety. In addition, since no Group 1 
participant was diagnosed on the basis of thick smear results, data will remain comparable 
between Groups 1 and 2. 
 
 

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VAC054 
(n=15)
VAC063A 
(n=15)
VAC063B 
(n=6)
(qPCR only)
10 0
10 1
10 2
10 3
10 4
10 5
10 6
Parasites/mL
 
Figure 7: Parasitaemia at the diagnosis timepoint in unvaccinated control volunteers in three 
prior P. falciparum blood-stage CHMI studies.  
In both the VAC054  [115] and VAC063 CHMI studies, where microscopy was used as a diagnostic 
measure alongside qPCR and clinical assessment, diagnosis was made over a wider range of 
parasitaemia compared to the VAC063B study, where thick blood smear microscopy was not 
performed. Diagnostic parasitaemia ranged between 1440-273,247 parasites/mL in the VAC054 
study, 815- 124063 parasites/mL in VAC063A and 7137- 100946 parasites/mL in the VAC063B 
CHMI. Individual and median data points are shown.  
On this basis, for Group 2 and 3, diagnostic criteria will be based on symptoms in-keeping with 
malarial infection results and real-time quantitative polymerase chain reaction (qPCR) only, i.e. 
thick film microscopy will not be used as a diagnostic measure, as summarised in the algorithm in 
Figure 8.  
Symptoms or signs that will be considered as indicative of symptomatic malarial infection will be 
fever >37.8oC, rigors or other severe symptoms or signs related to malarial infection, including, 
but not limited to, subjective feverishness, sweats, headache, myalgia, arthralgia, nausea or 
vomiting. 
Asexual blood-stage parasitaemia will be measured by qPCR for the pan-plasmodium 18S DNA 
gene. In the presence of symptoms or signs indicative of malarial infection, ≥5,000 genome 
copies/mL will be considered diagnostic but a PCR result ≥10,000 copies/mL will be considered 
positive, regardless of symptoms. All Investigators (except the Principal Laboratory Investigator) 
will be blinded to the results. Blinding of PCR operators to the vaccination status of a volunteer 
(as opposed to an infectivity control in the parallel VAC069 study) will be maintained by assigning 
a new unique identifier to the volunteer for PCR samples from the C-2 visit. If, as judged by the 
investigator, a volunteer develops symptoms in-keeping with malaria, the volunteer will be 
discussed with the Chief Investigator. If deemed appropriate by the Chief Investigator, the qPCR 
results for this volunteer will be unblinded by the Principal Laboratory Investigator and the 
volunteer treated only if any available qPCR result is ≥5000 genome copies/mL. At the point that 
a volunteer has a qPCR result exceeding 10,000 genome copies/mL, the Principal Laboratory 
Investigator will unblind the Chief Investigator to the result and the volunteer will be treated, 
regardless of the presence of symptoms.  

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Page 87 of 128 
Importantly, in the unlikely event of a technical failure with the qPCR machine, we also have a 
working back-up qPCR machine that will be available for use 24/7 if required. 
 
The Investigators are able to treat any volunteer for malaria regardless of the qPCR result if they 
are clinically concerned (and have discussed the case with the Chief Investigator), or a volunteer 
wishes to withdraw from the study. If necessary, volunteers can be discussed with the LSM 
and/or the infectious diseases consultant on call at the John Radcliffe Hospital for further 
management under the care of the infectious diseases team, inclusive of parenteral anti-malarial 
therapy if deemed appropriate.  
 
 
 
 
 
 
 
 
 
 
 
 
Figure 8: Algorithm for diagnosis and initiation of treatment of Group 2 and 3. N.B. If day 21 
after challenge is reached without meeting any diagnostic criteria, treatment will be initiated 
regardless of qPCR results, i.e. even if parasitaemia is undetectable. 
 
11.4.3 Participants with fever post malaria challenge and COVID-19 testing 
In the first week following CHMI, if a participant becomes unwell with a febrile illness, it is highly 
unlikely that the cause of this is malaria. If a participant develops a fever between days C+1 to 
C+6 and their symptoms are consistent with possible COVID-19 disease (fever or new onset 
persistent cough or anosmia or ageusia) the participant will be advised to self-isolate as per 
Public Health England (PHE) guidelines and directed to local community based COVID-19 testing. 
If the SARS-COV-2 PCR test is negative, the participant can stop self-isolation and continue with 
study visits as per protocol. 
From C+7 onwards, if a participant develops a fever of ≥37.8°C or other symptoms consistent 
with possible COVID-19 disease, they will be advised to inform the study team before attending 
their clinic visit and commence self-isolation as per PHE guidelines. As long as the participants’ 
symptoms are judged by the Investigator as not significant enough to require referral to 
secondary care, they will be advised to attend the study clinic where their visit will be conducted 
in a separately-accessed isolated clinic room with study staff wearing appropriate PPE. If a 
participant fulfils COVID-19 testing criteria, a SARS-COV-2 PCR swab from the nasopharynx and 
throat will be taken by the study team, in addition to the study specified malaria blood tests.  
qPCR 
≥5,000 
genome 
copies/mL
qPCR 
<5,000 
genome 
copies/mL
Negative 
diagnosis, 
continue 
monitoring 
Positive 
diagnosis, 
begin 
treatment 
qPCR 
<10,000 
genome 
copies/mL
qPCR 
>10,000 
genome 
copies/mL
Negative 
diagnosis, 
continue 
monitoring 
Positive 
diagnosis, 
begin 
treatment 
Symptomatic 
Asymptomatic/ 
clinical criteria for diagnosis not met 

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If a participant has a persistent fever or study clinicians are clinically concerned for COVID-19 
disease, then a SARS-COV-2 PCR swab can be repeated at the discretion of the Investigator, if the 
first SARS-COV-2 PCR was negative. 
If a participant is self-isolating because of symptoms of possible COVID-19 disease and they are 
unable to travel to the clinic safely, then a home visit may be conducted by the study team in lieu 
of a clinic visit to allow collection of safety and malaria blood tests. 
If following malaria challenge and prior to malaria diagnosis and treatment, a participant is found 
to have a positive SARS-COV-2 PCR swab from any source, they will be commenced on malaria 
treatment, irrespective of the severity of COVID-19 disease and irrespective of malaria symptoms 
or malaria qPCR result at that time point. 
All volunteers will undergo a combined nasopharyngeal and throat swab for SARS-COV-2 PCR on 
the day of malaria diagnosis when malaria treatment is commenced, unless they have had a 
negative COVID-19 PCR swab within the preceding 24 hours. The reasoning for this is that fever 
after commencement of malaria treatment is common and if a participant develops a fever after 
starting malaria treatment, a negative COVID-19 swab will allow exclusion of concurrent COVID-
19 disease and negate the need for self-isolation and household isolation.  
 
11.5 Malaria management 
Volunteers will be treated with a standard oral course of either artemether-lumefantrine 
(Riamet®) or atavoquone/proguanil (Malarone). Both are recommended treatment of P. vivax 
infection in the UK, although use for non-falciparum malaria is an unlicensed use for both 
medications. The decision on which medication will be used, will be at the Investigator’s 
discretion and depends on factors including if there are any contraindications to either 
medication. 
If a volunteer withdraws/is withdrawn from the study after administration of CHMI but before 
reaching the criteria for malaria treatment, then a complete, appropriate, curative course of anti-
malarial therapy must be completed. The importance of this will be emphasised to volunteers at 
screening. 
11.5.1 Riamet 
Artemisinin-based combination therapies (ACTs) containing mefloquine, piperaquine or 
lumefantrine are now the recommended treatment for P. vivax in areas where there might be 
chloroquine resistance (WHO 2015 guidelines). Although chloroquine remains effective in most 
recent studies in Thailand, there are some signs that low level chloroquine resistance may be 
becoming established along the Thai-Myanmar border. For this reason artemether-lumefantrine 
(Riamet®) will be one of the treatments used in this study.  
Riamet® is a combination drug consisting of 20mg artemether and 120mg lumefantrine per 
tablet. The treatment regime will consist of 6 doses of total 80mg artemether/480mg 
lumefantrine (4 tablets) – to clear the blood-stage infection. The first dose will be directly 
observed, at treatment initiation, followed by additional doses after 8, 24, 36, 48 and 60 hours 
(window period +/- 1 hour for each dose). The 24 hour dose will also be directly observed, and 
volunteers will record the time that intervening doses were taken at home in a medication diary.  
Prior to starting Riamet®, volunteers will be screened for drug interactions and contraindications. 
This includes checking for pregnancy by urine pregnancy test (serum β-hCG test in female 
volunteers at C+7 and C+14) and prolonged QT (on pre-challenge ECG). Volunteers will be 

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Page 89 of 128 
reminded of the potential side effects and given the patient information sheet for Riamet® and a 
card outlining when their doses of Riamet should be taken. Volunteers will be advised to avoid 
grapefruit juice. Tablets should be taken together with a fatty meal (a light snack will provided 
when doses are observed in clinic). At least two doses for each volunteer will be directly 
observed in clinic.  
11.5.2 Malarone  
Malarone (see SmPc for Malarone) is a combination drug consisting of proguanil hydrochloride 
and atovaquone. A treatment course of Malarone consists of 4 ‘standard tablets’ of Malarone 
(proguanil hydrochloride 100 mg, atovaquone 250 mg) once daily, orally for 3 days. The first two 
doses of Malarone will be directly observed in clinic. Prior to starting Malarone, volunteers will 
be screened for drug interactions and contraindications (including a serum β-hCG test in female 
volunteers). Volunteers will be reminded of the potential side effects of Malarone and given the 
patient information sheet for Malarone. 
11.5.3 Malaria management – supportive medications  
Provided there are no contraindications, volunteers will be provided with both a 5 day course of 
paracetamol (1 g orally up to four times a day) and a 5 day course of cyclizine (50 mg orally three 
times a day) (See SmPC for Paracetamol & Cyclizine). Participants may be provided with an 
appropriate, licensed alternative anti-emetic to cyclizine if they are unable to take cyclizine. 
Volunteers will be given the patient information sheet for these medications and advised how 
frequently they can take doses. Volunteers will be issued with a medication diary card on which 
they will be asked to document all doses of medications taken post-CHMI.   
All medications used in the trial will be handled and dispensed according to SOP VC021: 
Handling, Storage and Dispensing of Non-IMP Medication.  
11.5.4 Follow-up after commencing malaria treatment 
For Group 1 volunteers, at each visit, 24 hours and 48 hours after initiation of treatment, 
procedures will be performed according to Table 11, including physical observations, assessment 
of AEs and venepuncture for blood tests including measurement of malaria qPCR. Once daily 
malaria qPCR blood tests will continue until the volunteer has two consecutive qPCR readings 
with substantial reduction in genome copies per mL. 
For Group 2 and 3 volunteers post treatment visits will occur at 24 hours and 72 hours after 
initiation of treatment. Procedures will be performed according to Table 14, including physical 
observations, assessment of AEs and venepuncture for blood tests including measurement of 
malaria qPCR. Malaria qPCR blood tests can be repeated if qPCR readings are not substantially 
reduced by T+3. 
11.5.5 Criteria for inpatient transfer to the NHS  
If any of the following criteria are met, admission under the care of the Infectious Diseases Team, 
Oxford University Hospitals NHS Foundation Trust will be considered: 
 Failure of symptoms to improve within 48 hours of starting anti-malarial therapy. 
 Unable to tolerate oral antimalarial therapy. 
 Dehydration requiring intravenous fluid therapy. 
 Signs or symptoms suggestive of pulmonary oedema.  
 Signs or symptoms of neurological dysfunction including altered consciousness. 
 Signs, symptoms or laboratory evidence of significant renal dysfunction. 

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Page 90 of 128 
 Unanticipated concern about subject’s home circumstances. 
 Any other significant finding which the Investigators feels warrant inpatient admission - 
this includes symptoms or signs of suspected worsening COVID-19 disease e.g. respiratory 
failure, in the unlikely event of a participant testing PCR positive for COVID-19 during the 
post-challenge period. 
Ultimately, the decision regarding admission will be taken by the Investigators in conjunction 
with the Infectious Diseases Consultant on call.  
 
11.6 Safety measures for conduct of CHMI 
Volunteer safety is of paramount importance. The following measures are in place to safeguard 
volunteer safety: 
 Volunteers will only be enrolled in the study if both Investigators and the volunteers’ GP 
feel this is appropriate. 
 Volunteers’ understanding of the trial information will be tested by means of a 
questionnaire at screening. This provides further confidence that fully informed consent 
has been obtained. 
 If the subject does not have their own mobile telephone they will be issued with one for 
the duration of the study and counselled about the importance of keeping it switched on 
or checking the messages regularly.  
 Before challenge, full contact details for each subject will be documented, including home 
address and mobile telephone numbers. Mobile telephone numbers will be verified prior 
to challenge to ensure the volunteers are easily contactable. Home and work landline 
telephone numbers where available and next-of-kin address and telephone numbers will 
also be documented. Subjects must also provide the Investigators with the name and 24 
hour telephone number of a close friend, relative or housemate who lives nearby and will 
be kept informed of their whereabouts for the duration of the study. 
 On the day of challenge volunteers will be provided with a medic alert card containing 
contact details for the study team and brief details of the study including the optimal 
treatment for P. vivax. 
 Volunteers will be able to contact a medically qualified member of the study team 24 
hours a day throughout the study period and will be instructed to contact the Investigator 
immediately should they manifest any signs or symptoms they perceive as serious. 
 If necessary, the study team will visit volunteers in their own homes if they are unable to 
attend clinic for review.  
 At least two doses of the Riamet® for each volunteer will be observed by the study team. 
For volunteers taking Malarone, two out of three doses will be observed. 
 Volunteers will be counselled that should they fail to return for treatment having been 
infected with P. vivax they could become very unwell and potentially die. They will be 
instructed to remain in Oxford and the immediate surrounding area for the duration of 
the intensive follow-up schedule (days 0-30 post-challenge). They will be informed that 
should they fail to attend a scheduled clinic visit post-challenge, their nominated contact, 
next of kin and the police may be informed and a search started.  

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Page 91 of 128 
11.6.1 Measures to be taken if a volunteer goes missing post-CHMI 
In the unlikely event that a volunteer should (a) fail to attend for a scheduled clinical visit or (b) 
be un-contactable by telephone after challenge and before completion of an appropriate course 
of anti-malarial therapy, the following stakeholders will be informed; 
 All Investigators.  
 The volunteer’s nominated contact and next of kin. 
 The trial Sponsor. 
 The local safety committee. 
 The ethical committee(s). 
 Relevant hospital trust R&D departments. 
 The local police department. 
 Local Accident and Emergency departments. 
Active efforts will be made to locate the volunteer by the police. While all parties will aim to 
preserve the volunteer’s confidentiality, if necessary details of the volunteer’s identity and 
participation in the study may be passed to the national media in order to help locate the missing 
individual. Volunteers will be informed of this during screening. 
11.7 Follow-up post-treatment  
11.7.1 Six days after initiation of treatment (T+6) 
Physical observations will be performed and AEs assessed. Venepuncture will be performed 
(Table 11 for Group 1; Table 14 for Groups 2 and 3). Where applicable, medication diary and 
malaria symptom diary cards will be collected from volunteers. 
11.7.2 Nine days after initiation of treatment (T+9) 
Volunteers will be phoned at 9 days post day of diagnosis visit (treatment initiation) (as per Table 
11 for Group 1; Table 14 for Groups 2 and 3). Participants will be questioned as to whether they 
have; 
o Experienced any of the foreseeable symptoms of malaria. 
o Experienced any other symptoms.  
o Taken any medications including over the counter medications. 
11.7.3 Day 56 post CHMI (C+56) 
Physical observations will be performed and AEs assessed. Venepuncture will be performed 
(Table 11 for Group 1; Table 14 for Groups 2 and 3).  
11.7.4 Day 96 post CHMI (C+96)  
Physical observations will be performed and AEs assessed. Venepuncture will be performed 
(Table 11 for Group 1; Table 14 for Groups 2 and 3).  
11.7.5 Day 276 post CHMI (C+276)  
Physical observations will be performed and AEs assessed. Venepuncture will be performed 
(Table 11 for Group 1; Table 14 for Groups 2 and 3). 
 

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 92 of 128 
S
ChAd63 
PvDBP 
MVA PvDBP
Attendance number 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
Timeline (days)  
0  
1  
3  
7  
14  
28 
56  
57  
59  
63  
70  
Window (days)
-90
±1
±1
-1/+2
-2/+4
-3/+5
-7/+10
±14
±1
-1/+2
-2/+4
-3/+5
Inclusion/Exclusion criteria 
X 
X 
  
  
  
  
 
X 
  
  
  
  
Informed consent
X
(X)
(X)
ICQ 
X 
  
  
  
  
  
 
  
  
  
  
  
Physical observations*
X
X
X
X
X
X
X
X
X
X
X
X
Medical history/ examination 
X 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
ECG
X
Urinalysis
X
Urine β-hCG**
X
X
X
Review contraindications
X
X
Review AEs & medications
X
X
X
X
X
X
X
X
X
X
Vaccination 
  
X 
  
  
  
  
 
X 
  
  
  
  
Diary card issued
X
X
Diary card collected 
  
  
  
  
X 
  
X 
  
  
  
X 
  
Immunology(mL)
83
23
20
40
40
83
23
20
50
80
Haematology (mL)#
4 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
Biochemistry (mL) ## 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
DARC (mL)
2
HLA typing (mL)
4
HIV, HBV, HCV, EBV, CMV serology (mL) 
5 
  
  
  
  
  
 
  
  
  
  
  
Total Blood Volume (mL)^ 
14 
92 
28 
25 
45 
45 
5 
88 
28 
25 
55 
85 
Cumulative blood volume (mL)^ 
14 
106 
134 
159 
204 
249 
254 
342 
370 
395 
450 
535 
Table 7a: Schedule of events for Group 1 and 3 volunteers pre-CHMI  
S = screening visit; ICQ = Informed Consent questionnaire; (X) = If considered necessary, emphasising any acute complaints. *Physical observations will include blood pressure, pulse and 
temperature, plus height and weight at screening only. **For females only. # Haematology will include full blood count plus G6PD level and haemoglobinopathy screen at screening only.## 
Biochemistry will include sodium, potassium, urea, creatinine, albumin, liver function test, plus magnesium and calcium at screening only. For Group 2 & 3 participants, CRP may also be 
performed on vaccination day and days 1, 3 and 7 following each vaccination. ^Blood volumes as given in the table are maximal volumes and smaller blood volumes may be taken at any visit, 
at the discretion of the investigator, with the exception of additional blood volume that may be required for any additional tests that may be performed if deemed clinically necessary.  

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 93 of 128 
S
ChAd63 
PvDBP
ChAd63 
PvDBP
MVA 
PvDBP
Attendance number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Timeline (days) 
Post boost (PB) (days) 
0 
 
1 
3 
7 
14 
28
PB0 
PB1 
PB3  
PB7  
PB14  
PB28 
PB56  
PB57 
PB59 
PB63 
PB70 
Window (days)
-90
±1
±1
±1
±1
±2
±2
±1
±1
-1/+2
-2/+4
-3/+5
-7/+10
±14 
±1
-1/+2
-2/+4
-3/+5
Inclusion/Exclusion 
criteria
X
X
X
X
Informed consent
X
(X)
(X)
(X)
ICQ
X
Physical observations* 
X 
X 
X 
X 
X 
X 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Medical history/ 
examination 
X 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
(X) 
ECG 
X 
  
  
  
  
  
 
 
  
  
  
  
  
 
  
  
  
  
  
Urinalysis 
X 
  
  
  
  
  
 
 
  
  
  
  
  
 
  
  
  
  
  
Urine β-hCG** 
X 
X 
  
  
  
  
 
 
X 
  
  
  
  
 
X 
  
  
  
  
Review 
contraindications 
X
X
X
Review AEs & 
medications
  
X 
X 
X 
X 
X 
 
 
X 
X 
X 
X 
X 
 
X 
X 
X 
X 
X 
Vaccination 
  
X 
  
  
  
  
 
 
X 
  
  
  
  
 
X 
  
  
  
  
Diary card issued 
  
X 
  
  
  
  
 
 
X 
  
  
  
  
 
X 
  
  
  
  
Diary card collected 
  
  
  
  
X 
  
X 
 
  
  
  
X 
  
X 
  
  
  
X 
  
Immunology (mL) 
  
83 
23 
20 
40 
40 
 
 
83 
23 
20 
40 
40 
 
83 
23 
20 
50 
80 
Haematology (mL)# 
4 
2 
2 
2 
2 
2 
2 
 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
Biochemistry (mL) ## 
3 
3 
3 
3 
3 
3 
3 
 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
DARC (mL) 
2 
  
  
  
  
  
 
 
  
  
  
  
  
 
  
  
  
  
  
HLA typing (mL)
4
HIV, HBV, HCV, EBV, 
CMV serology (mL) 
5
Total Blood Volume 
(mL)^ 
14 
92 
28 
25 
45 
45 
5 
 
88 
28 
25 
45 
45 
5 
88 
28 
25 
55 
85 
Cumulative blood 
volume (mL)^
14
106
134
159
204
249
254
342
370
395
440
485
490
578
606
631
686
771

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 94 of 128 
Table 7b: Schedule of events for Group 2 volunteers pre-CHMI  
PB0 will occur between 12-18 months after D0. S = screening visit; ICQ = Informed Consent questionnaire; (X) = If considered necessary, emphasising any acute complaints. *Physical 
observations will include blood pressure, pulse and temperature, plus height and weight at screening only. **For females only. # Haematology will include full blood count plus G6PD level and 
haemoglobinopathy screen at screening visit only.## Biochemistry will include sodium, potassium, urea, creatinine, albumin, liver function test, plus magnesium & calcium screening only. For 
Group 2 & 3 participants, CRP may also be performed on each vaccination day and days 1, 3, and 7 following each vaccination. ^Blood volumes as given in the table are maximal volumes and 
smaller blood volumes may be taken at any visit, at the discretion of the investigator, with the exception of additional blood volume that may be required for any additional tests that may be 
performed if deemed clinically necessary.  
 

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 95 of 128 
  
 
C-2 
CHMI
C+1-C+6 
C+7
C+8
C+9
C+10 
C+10.5 
C+11 
C+11.5
C+12 
C+12.5
C+13 
C+13.5
C+14 
C+14.5 
Attendance number – Group 1 
13 
14 
15 
16 
17 
18 
19 
20 
20 
21 
22 
23 
24 
25 
26 
27 
Timeline (days)  
-2 
0 
1-6 
7 
8 
9 
10 
10 
11 
11 
12 
12 
13 
13 
14 
14 
Window (days) 
±1 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Inclusion/Exclusion criteria 
X  
X  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Informed consent 
X  
 X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Daily telephone call 
  
  
 X 
  
  
  
  
  
  
  
  
  
  
  
  
  
Physical observations* 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Medical history/ examination 
 (X) 
(X)  
 (X) 
 (X) 
(X)  
 (X) 
 (X) 
 (X) 
(X)  
 (X) 
 (X) 
(X)  
 (X) 
 (X) 
 (X) 
  (X) 
Review contraindications 
 X 
 X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Review AEs & medications 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Diary card issued 
 X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Diary card collected 
 X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Medic alert card issued 
X  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
Immunology (mL) 
80 
 
 
60 
 
 
 
  
  
  
  
  
  
  
60 
  
Serum storage (mL) 
4 
 
 
 
 
 
 
  
  
  
  
  
  
  
 
  
qPCR/GctPCR (mL) 
3 
 
 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
Group 1 only: blood film (mL) 
1 
 
 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
Haematology (mL)# 
 2 
  
  
2 
  
  
  
  
  
  
  
  
  
  
2 
  
Biochemistry (mL) ## 
 3 
  
  
3 
 
 
 
 
 
 
 
 
 
 
3 
 
Serum βhCG (mL)** 
 5 
  
  
5 
 
 
 
 
 
 
 
 
 
 
5 
 
SARS-COV-2 PCR swab 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Visit total Blood Volume (mL)^
98
0
0
74
4
4
4
4
4
4
4
4
4
4
74
4
Cumulative blood volume (mL)^ 
633 
633 
633 
707 
711 
715 
719 
723 
727 
730 
734 
738 
742 
746 
820 
824 
Table 8: Groups 1 - Schedule of events for day of challenge – day 14 after challenge  (timeline/window are in relation to the day of challenge). (X) = If considered necessary. Visits 
continue until diagnosis; when diagnostic criteria are met, venepuncture and procedures are followed according to Table 11. *Physical observations will include blood pressure, pulse 
and temperature, plus weight and height at C-2 visit. **For females only. #Haematology will comprise full blood count only. ## Biochemistry will include sodium, potassium, urea, 
creatinine, albumin and liver function tests. Blood volumes as given in the table are maximal volumes and smaller blood volumes may be taken at any visit, at the discretion of the 
investigator, with the exception of additional blood volume that may be required for any additional tests that may be performed if deemed clinically necessary. 
 
 

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 96 of 128 
  
 
C+15 
C+15.5 
C+16 
C+16.5 
C+17 
C+17.5 
C+18 
C+18.5 
C+19 
C+19.5 
C+20 
C+20.5 
C+21 
C+21.5 
Attendance number – Group 1 
28 
29 
30 
31 
32 
33 
34 
35 
36 
37 
38 
39 
40 
41 
Timeline (days)  
15 
15 
16 
16 
17 
17 
18 
18 
19 
19 
20 
20 
21 
21 
Window (days) 
 
  
  
  
  
  
  
  
  
  
  
  
  
  
Physical observations* 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Medical history/ examination 
 (X) 
 (X)  
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
Review AEs & medications 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Immunology (mL) 
 
 
 
 
 
 
 
 
 
 
 
 
60 
 
qPCR/GctPCR (mL) 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
Blood film (mL) 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
Haematology (mL)# 
 
 
 
 
 
 
 
 
 
 
 
 
2 
 
Biochemistry (mL) ## 
 
 
 
 
 
 
 
 
 
 
 
 
3 
 
Serum βhCG (mL)** 
 
 
 
 
 
 
 
 
 
 
 
 
5 
 
Visit total blood volume (mL)^
4
4
4
4
4
4
4
4
4
4
4
4
74
4
Cumulative blood volume (mL)^ 
828 
832 
836 
840 
844 
848 
852 
856 
860 
864 
868 
872 
946 
950 
Table 9: Group 1 - Schedule of events for days 15-21 after challenge (timeline/window are in relation to the day of challenge). (X) = If considered necessary. Visits continue until 
diagnosis; when diagnostic criteria are met, venepuncture and procedures are followed according to Table 11. *Physical observations will include blood pressure, pulse and 
temperature. **For females only. #Haematology will comprise full blood count only. ## Biochemistry will include sodium, potassium, urea, creatinine, albumin and liver function 
tests. ^Blood volumes as given in the table are maximal volumes and smaller blood volumes may be taken at any visit, at the discretion of the investigator, with the exception of 
additional blood volume that may be required for any additional tests that may be performed if deemed clinically necessary. 

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 97 of 128 
  
 
C+22 
C+22.5 
C+23 
C+23.5 
C+24 
C+24.5 
C+25 
C+25.5 
C+26 
C+26.5 
C+27 
C+27.5 
Attendance number – Group 1 
42 
43 
44 
45 
46 
47 
48 
49 
50 
51 
52 
53 
Timeline (days)  
22 
22 
23 
23 
24 
24 
25 
25 
26 
26 
0 
27 
Window (days) 
 
  
  
  
  
  
  
  
  
  
  
  
Physical observations* 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Medical history/ examination 
 (X) 
 (X)  
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
Review AEs & medications 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Immunology (mL) 
 
 
 
 
 
 
 
 
 
 
 
 
Serum storage (mL) 
 
 
 
 
 
 
 
 
 
 
 
 
qPCR/GctPCR (mL) 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
Blood film (mL) 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
Haematology (mL)# 
 
 
 
 
 
 
 
 
 
 
 
 
Biochemistry (mL) ## 
 
 
 
 
 
 
 
 
 
 
 
 
Serum βhCG (mL)** 
 
 
 
 
 
 
 
 
 
 
 
 
Visit total blood volume (mL)^ 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
Cumulative blood volume (mL)^ 
954 
958 
962 
966 
970 
974 
978 
982 
986 
990 
994 
998 
Table 10: Group 1 - Schedule of events for days 22-27.5 after challenge (timeline/window are in relation to the day of challenge). (X) = If considered necessary. Visits continue until 
diagnosis; when diagnostic criteria are met, venepuncture and procedures are followed according to Table 11. *Physical observations will include blood pressure, pulse and 
temperature. **For females only. #Haematology will comprise full blood count only. ## Biochemistry will include sodium, potassium, urea, creatinine, albumin and liver function 
tests. ^Blood volumes as given in the table are maximal volumes and smaller blood volumes may be taken at any visit, at the discretion of the investigator, with the exception of 
additional blood volume that may be required for any additional tests that may be performed if deemed clinically necessary.

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 98 of 128 
  
 
DOD/C+28 (if 
undiagnosed) 
T+1  
(24hr dose)$ 
T+2  
(48hr dose)$ 
T+6 
C+56 
C+96 
C+276 
Attendance number – Group 1 
54 
55 
56 
57 
58 
59 
60 
Timeline (days)  
 - 
 - 
-  
- 
56 
69 
276 
Window (days)
±1
±14
±14
±14
Physical observations* 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Medical history/ examination 
 (X) 
 (X)  
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
Urine β-hCG** 
 X 
  
  
 
 
 
 
Review contraindications 
 X 
  
  
  
  
  
Review AEs & medications
X
X
X
X
X
X
X
Diary card collected 
  
  
  
 X 
 (X) 
  
  
Immunology (mL) 
70$$ 
 
 
 
80 
70 
70 
Serum storage (mL) 
 
 
 
 
 
4 
 
qPCR/GctPCR (mL)
3
3
3
Blood film (mL) 
1 
1 
1 
 
 
 
 
Haematology (mL)# 
2 
  
  
2 
2 
2 
 
Biochemistry (mL) ## 
3 
  
  
3 
3 
3 
 
Serum βhCG (mL)**
5
HIV, HBV, HCV, EBV***, CMV*** serology (mL)
5***
SARS-COV-2 PCR swab 
X 
 
 
 
 
 
 
 Visit total blood volume (mL)^ 
79 
4 
4 
5 
85 
84 
70 
Cumulative blood volume (mL)^ 
1077 
1081 
1085 
1090 
1175 
1259 
1329 
Table 11: Group 1 - Schedule of events from diagnosis to 276 days after challenge (timeline/window are in relation to the day of challenge or treatment day). DoD = day of 
diagnosis; C = challenge; T = treatment; (X) = If considered necessary.*Physical observations will include blood pressure, pulse and temperature. **For females only. #Haematology 
will comprise full blood count only. ## Biochemistry will include sodium, potassium, urea, creatinine, albumin and liver function tests. ^Blood volumes as given in the table are 
maximal volumes and smaller blood volumes may be taken at any visit, at the discretion of the investigator, with the exception of additional blood volume that may be required for 
any additional tests that may be performed if deemed clinically necessary. ***Blood-borne viral serology (for HIV, HBC, HCV, EBV and CMV) will either be performed on a fresh blood 
sample taken at C+96 or on stored serum, at the discretion of the investigator. However, EBV and CMV serology will only be repeated post-challenge if the participant had negative 
serology results at screening. $Blood draws for qPCR will continue daily until the volunteer has two consecutive qPCR readings with substantial reduction in genome copies per mL.  
$$If DoD visit takes place within 24 hours of C+7, C+14 or C+21 visit, the immunology blood draw will not be taken, since a large immunology blood draw (60mL) will have been taken 
at C+7/C+14/C+21. ^Blood volumes as given in the table are maximal volumes and smaller blood volumes may be taken at any visit, at the discretion of the investigator, with the 
exception of additional blood volume that may be required for any additional tests that may be performed if deemed clinically necessary. 
 

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 99 of 128 
  
C-2 
CHMI 
C+1-
C+6 
C+7 
C+8 
C+9 
C+10 
C+10.5$ 
C+11 
C+11.5$ 
C+12 
C+12.5$ 
C+13 
C+13.5$ 
C+14 
C+14.5$ 
Attendance number – Group 2 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
31 
32 
33 
34 
Attendance number – Group 3 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
Timeline (days)  
-2 
0 
1-6 
7 
8 
9 
10 
10 
11 
11 
12 
12 
13 
13 
14 
14 
Window (days) 
±1 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Inclusion/Exclusion criteria 
X  
X  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Informed consent 
X  
X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Daily telephone call 
  
  
X 
  
  
  
  
  
  
  
  
  
  
  
  
  
Physical observations* 
X 
X 
X 
 X 
 X 
X 
 X 
 X 
 X 
X 
 X 
X 
 X 
X 
 X 
X 
Medical history/ examination 
 (X) 
(X)  
 (X) 
 (X) 
(X)  
 (X) 
 (X) 
 (X) 
(X)  
 (X) 
 (X) 
(X)  
 (X) 
 (X) 
 (X) 
  (X) 
Review contraindications 
 X 
 X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Review AEs & medications 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Diary card issued 
 X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Diary card collected 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Medic alert card issued 
X 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
Malaria challenge 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Immunology (mL) 
80 
 
 
60 
 
 
 
  
  
  
  
  
  
  
60 
  
Serum storage (mL) 
4 
 
 
 
 
 
 
  
  
  
  
  
  
  
 
  
qPCR/GctPCR (mL) 
2 
 
 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
Haematology (mL)# 
2 
  
  
2 
  
  
  
  
  
  
  
  
  
  
2 
  
Biochemistry (mL) ## 
3 
  
  
3 
 
 
 
 
 
 
 
 
 
 
3 
 
Serum βhCG (mL)** 
5 
  
  
5 
 
 
 
 
 
 
 
 
 
 
5 
 
SARS-COV-2 PCR swab 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Total Blood Volume (mL)^ 
96 
0 
0 
72 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
72 
2 
Group 2 - Cumulative blood 
volume (mL)^ 
867 
867 
867 
939 
941 
943 
945 
947 
949 
951 
953 
955 
957 
959 
1031 
1033 
Group 3 - Cumulative blood 
volume (mL)^  
631 
631 
631 
703 
705 
707 
709 
711 
713 
715 
717 
719 
721 
723 
795 
797 

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 100 of 128 
Table 12: Groups 2 & 3 - Schedule of events for day before challenge to day 14 after challenge (timeline/window are in relation to the day of challenge). Visits continue until 
diagnosis; when diagnostic criteria are met, venepuncture and procedures are followed according to Table 14.  $From day 10 post challenge onwards, visits will continue once a day 
in mornings, increasing to twice daily if the malaria qPCR count is >1000 genome copies/ml. (X) = If considered necessary. *Physical observations will include blood pressure, pulse 
and temperature, plus weight at C-2 visit. **For females only. #Haematology will comprise full blood count only. ## Biochemistry will include sodium, potassium, urea, creatinine, 
albumin and liver function tests. ^Blood volumes as given in the table are maximal volumes and smaller blood volumes may be taken at any visit, at the discretion of the investigator, 
with the exception of additional blood volume that may be required for any additional tests that may be performed if deemed clinically necessary. 
 
 

VAC071 Clinical Trial Protocol, V9.0, 14th June 2022, University of Oxford.  
 
Page 101 of 128 
  
C+15 
C+15.5$ 
C+16 
C+16.5$ 
C+17 
C+17.5$ 
C+18 
C+18.5$ 
C+19 
C+19.5$ 
C+20 
C+20.5$ 
Attendance number - Group 2  
35 
36 
37 
38 
39 
40 
41 
42 
43 
44 
45 
46 
Attendance number - Group 3  
29 
30 
31 
32 
33 
34 
35 
36 
37 
38 
39 
40 
Timeline (days) 
15 
15 
16 
16 
17 
17 
18 
18 
19 
19 
20 
20 
Physical observations* 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Medical history/ examination 
 (X) 
 (X)  
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
 (X) 
Review AEs & medications 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
 X 
Diary card issued 
  
  
  
  
  
  
  
  
  
  
  
Diary card collected 
  
  
  
  
  
  
  
  
  
  
  
  
Medic alert card issued 
  
 
 
 
 
 
 
 
 
 
Immunology (mL) 
 
 
 
 
 
 
 
 
 
 
 
 
Serum storage (mL) 
 
 
 
 
 
 
 
 
 
 
 
 
qPCR/GctPCR (mL) 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
Haematology (mL)# 
 
 
 
 
 
 
 
 
 
 
 
 
Biochemistry (mL) ## 
 
 
 
 
 
 
 
 
 
 
 
 
Serum βhCG (mL)** 
 
 
 
 
 
 
 
 
 
 
 
 
Total Blood Volume (mL)^ 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
2 
Group 2 - Cumulative blood 
volume (mL)^ 
1035 
1037 
1039 
1041 
1043 
1045 
1047 
1049 
1051 
1053 
1055 
1057 
Group 3 - Cumulative blood 
volume (mL)^ 
799 
801 
803 
805 
807 
809 
811 
813 
815 
817 
819 
821 
Table 13: Groups 2 & 3 - Schedule of events from day 15 - 20 after challenge (timeline/window are in relation to the day of challenge). Visits continue until diagnosis; when 
diagnostic criteria are met, venepuncture and procedures are followed according to Table 14. $From day 10 post challenge onwards, visits will continue once a day in mornings, 
increasing to twice daily if the malaria qPCR count is >1000 genome copies/ml. (X) = If considered necessary. *Physical observations will include blood pressure, pulse and 
temperature. **For females only. #Haematology will comprise full blood count only. ## Biochemistry will include sodium, potassium, urea, creatinine, albumin and liver function 
tests. ^Blood volumes as given in the table are maximal volumes and smaller blood volumes may be taken at any visit, at the discretion of the investigator, with the exception of 
additional blood volume that may be required for any additional tests that may be performed if deemed clinically necessary. 
 
 

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DOD/C+21 (if 
undiagnosed) + 
T+1 
(24hr dose) 
T+3^^ 
T+6 
T+9 
C+56 
C+96 
C+276 
Attendance number - Group 2 
47 
48 
49 
50 
 
51 
52 
53 
Attendance number - Group 3 
41 
42 
43 
44 
n/a 
45 
46 
47 
Timeline (days) 
-
-
-
-
56
96
276
Window (days) 
 
  
  
±1 
±2 
±14 
±14 
±14 
Telephone call 
 
 
 
  
X 
  
  
  
Physical observations* 
 X 
 X 
 X 
 X 
 
 X 
 X 
 X 
Medical history/ examination 
 (X) 
 (X)  
 (X) 
 (X) 
 
 (X) 
 (X) 
 (X) 
Urine β-hCG**
X
Review contraindications 
 X 
  
  
 
  
  
  
Review AEs & medications 
 X 
 X 
 X 
 X 
 
 X 
 X 
 X 
Diary card issued 
  
  
  
 
  
  
  
Diary card collected
X
Immunology (mL) 
70$ 
 
 
 
 
80 
70 
70 
Serum storage (mL) 
 
 
 
 
 
 
4 
 
HIV, HBV, HCV, EBV, CMV serology (mL)+++ 
 
 
 
 
 
 
5 
 
qPCR/GctPCR (mL)
2
2
2
Haematology (mL)#
2
2
2
2
Biochemistry (mL) ## 
3 
  
  
3 
 
3 
3 
 
Serum βhCG (mL)** 
5 
 
 
 
 
 
 
  
SARS-COV-2 PCR swab 
X 
 
 
 
 
 
 
 
Total Blood Volume (mL)^ 
82 
2 
2 
5 
n/a 
85 
84 
70 
Group 2 - Cumulative blood volume (mL)^ 
1139
1141
1143
1148
n/a
1233
1317
1387
Group 3 - Cumulative blood volume (mL)^  
903 
905 
907 
912 
n/a 
997 
1081 
1151 
Table 14: Group 2 (1st CHMI) and Group 3 (2nd CHMI) - Schedule of events from diagnosis to 276 days after challenge (timeline/window are in relation to the day of challenge or 
treatment day). DOD = day of diagnosis; C = challenge; T = treatment; (X) = If considered necessary. *Physical observations will include blood pressure, pulse and temperature. **For 
females only. #Haematology will comprise full blood count only. ## Biochemistry will include sodium, potassium, urea, creatinine, albumin and liver function tests. $ if diagnosed at 
C+14.5 do not take DOD immunology bleed (will have taken full bleed at C+14). + immediately before drug treatment. ^^ Blood draws for qPCR will continue until the volunteer has 
two consecutive qPCR readings with substantial reduction in genome copies per mL. +++ EBV and CMV serology will only be repeated at the C+96 timepoint if they were negative at 
screening. ^Blood volumes as given in the table are maximal volumes and smaller blood volumes may be taken at any visit, at the discretion of the investigator, with the exception of 
additional blood volume that may be required for any additional tests that may be performed if deemed clinically necessary.

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12 ASSESSMENT OF SAFETY 
Safety will be assessed by the frequency, incidence and nature of adverse events and serious 
adverse events arising during the study. The safety profile will be assessed on an on-going basis 
by the Investigators. The LSM will perform independent external safety reviews prior to 
progression to enrolment of Group 2 volunteers. The Chief investigator, Principal Investigator, 
and relevant Investigators (as per the trial delegation log) will also review safety issues and SAEs 
as they arise. 
12.1 Interim Safety Review 
Provided no holding criteria for progression to enrolment of Group 2 volunteers have been met 
(as described in Section 12.6.2), prior to enrolment of Group 2 volunteers the Local Safety 
Monitor will be consulted to provide a review of safety data and adverse events in volunteers 
before proceeding to vaccination of Group 2 participants. At least two volunteers should have 
received a heterologous prime-boost regimen of ChAd63 PvDBP and MVA PvDBP, undergone 
challenge and completed 28 days of follow-up after CHMI and at least 6 days of follow-up post 
completion of antimalarials, before the safety review is conducted. There will then be a 
minimum interval of two weeks to allow for the independent safety review events by the Local 
Safety Monitor. If there are no safety concerns, enrolment of Group 2 volunteers may 
commence. Interim safety data may also be made available to manufacturers (in coded format) 
as specified in the contract with the manufacturer(s). 
12.2 Definitions 
12.2.1 Adverse Event (AE) 
An AE is any untoward medical occurrence in a volunteer, which may occur during or after 
administration of an Investigational Medicinal Product (IMP) and does not necessarily have a 
causal relationship with the intervention. An AE can therefore be any unfavourable and 
unintended sign (including an abnormal laboratory finding), symptom or disease temporally 
associated with the study intervention, whether or not considered related to the study 
intervention. 
Each participant reported adverse event will be graded by the participant according to the table 
for grading severity of adverse events (see section 10.4). Severity gradings may be reviewed and 
discussed with the participants at the clinic visits. 
12.2.2 Adverse Reaction (AR) 
An AR is any untoward or unintended response to an IMP. This means that a causal relationship 
between the IMP and an AE is at least a reasonable possibility, i.e. the relationship cannot be 
ruled out. All cases judged by the reporting medical Investigator as having a reasonable 
suspected causal relationship to an IMP (i.e. possibly, probably or definitely related to an IMP) 
will qualify as adverse reactions. 
12.2.3 Unexpected Adverse Reaction  
An adverse reaction, the nature or severity of which is not consistent with the applicable product 
information (e.g., IB for an unapproved IMP). 

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12.2.4 Serious Adverse Event (SAE) 
An SAE is an AE that results in any of the following outcomes, whether or not considered related 
to the study intervention. 
 Death. 
 Life-threatening event (i.e. the volunteer was, in the view of the Investigator, at immediate 
risk of death from the event that occurred). This does not include an AE that, if it occurred 
in a more severe form, might have caused death. 
 Persistent or significant disability or incapacity (i.e. substantial disruption of one’s ability to 
carry out normal life functions). 
 Hospitalisation or prolongation of hospitalisation, regardless of length of stay, even if it is 
a precautionary measure for continued observation. Hospitalisation (including inpatient or 
outpatient hospitalisation for an elective procedure) for a pre-existing condition that has 
not worsened unexpectedly does not constitute a serious AE. 
 An important medical event (that may not cause death, be life threatening, or require 
hospitalisation) that may, based upon appropriate medical judgment, jeopardise the 
volunteer and/or require medical or surgical intervention to prevent one of the outcomes 
listed above. Examples of such medical events include allergic reaction requiring intensive 
treatment in an emergency room or clinic, blood dyscrasias, or convulsions that do not 
result in inpatient hospitalisation. 
 Congenital anomaly or birth defect. 
12.2.5 Serious Adverse Reaction (SAR) 
An adverse event (expected or unexpected) that is both serious and, in the opinion of the 
reporting Investigator or Sponsors, believed to be possibly, probably or definitely due to an IMP 
or any other study treatments including P. vivax CHMI, based on the information provided. 
12.2.6 Suspected Unexpected Serious Adverse Reaction (SUSAR) 
A serious adverse reaction, the nature and severity of which is not consistent with the 
information about the medicinal product in question set out in the IB, non-investigational 
medicinal product dossier (for P. vivax blood inoculum) or Summary of Product Characteristics 
(SmPC). 
12.2.6 Foreseeable Adverse Reactions 
The foreseeable ARs following vaccination with ChAd63 PvDBP and MVA PvDBP include injection 
site pain, erythema, warmth, swelling, pruritus, myalgia, arthralgia, headache, fatigue, fever, 
feverishness, malaise and nausea. These adverse events will be listed as solicited adverse events 
providing they occur within 7 days of the day of vaccination. AEs other than these, or those AEs 
occurring outside of the 7 days after vaccination, will be listed as unsolicited adverse events. 
12.2.7 Other Foreseeable Medical Occurrences 
The following medical occurrences are foreseeable: 
 Clinical P. vivax disease resulting in one or more of fever, tachycardia, hypotension, 
feverishness, chills, rigor, sweats, headache, anorexia, nausea, vomiting, myalgia, 
arthralgia, low back pain, fatigue, lymphopenia and thrombocytopenia; 
 Clinical P. vivax disease resulting in inpatient transfer of care to the NHS;  

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 Adverse reactions to Riamet®, Malarone, paracetamol or cyclizine, as detailed in the 
SmPCs for these medications. 
12.2.8 Expected Serious Adverse Events 
No serious adverse events are expected in this study. 
12.3 Causality Assessment 
For every unsolicited AE, an assessment of the relationship of the event to the administration of 
the vaccine will be undertaken by the CI or the CI-delegated clinician at the coordinating site 
(Oxford). An intervention-related AE refers to an AE for which there is a probable or definite 
relationship to administration of a vaccine. An interpretation of the causal relationship of the 
intervention to the AE in question will be made, based on the type of event; the relationship of 
the event to the time of vaccine administration; and the known biology of the vaccine therapy 
(Table 15). Causality assessment will take place during planned safety reviews, interim analyses 
(e.g. if a holding or stopping rule is activated) and at the final safety analysis, except for SAEs, for 
which causality should be assigned by the reporting Investigator. 
0 
No 
Relationship 
No temporal relationship to study product and 
Alternate aetiology (clinical state, environmental or other 
interventions); and 
Does not follow known pattern of response to study product 
1 
Unlikely 
Unlikely temporal relationship to study product and 
Alternate aetiology likely (clinical state, environmental or other 
interventions) and 
Does not follow known typical or plausible pattern of response to 
study product. 
2 
Possible 
 
Reasonable temporal relationship to study product; or 
Event not readily produced by clinical state, environmental or other 
interventions; or 
Similar pattern of response to that seen with other vaccines 
3 
Probable 
 
Reasonable temporal relationship to study product; and 
Event not readily produced by clinical state, environment, or other 
interventions or  
Known pattern of response seen with other vaccines 
4 
Definite 
 
Reasonable temporal relationship to study product; and 
Event not readily produced by clinical state, environment, or other 
interventions; and  
Known pattern of response seen with other vaccines 
Table 15: Guidelines for assessing the relationship of vaccine administration to an AE. 

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12.4 Reporting Procedures for All Adverse Events  
All AEs occurring in the 28 days following each vaccination observed by the Investigator or 
reported by the volunteer, whether or not attributed to study medication, will be recorded. 
Recording and reporting of all AEs will take place as detailed in SOP VC027. All AEs occurring in 
post-CHMI, until 6 days after completion of antimalarial treatment (i.e. 9 days after treatment 
initiation) will also be recorded- these will be entered directly into the eCRF. We will NOT record 
bruising due to blood-taking or cannulation.  All AEs that result in a volunteer’s withdrawal from 
the study will be followed up until a satisfactory resolution occurs, the event is considered stable 
or until a non-study related causality is assigned (if the volunteer consents to this). Serious 
adverse events (SAEs) will be collected throughout the entire trial period.  
Each adverse event will be graded by the participant according to the table for grading severity of 
adverse events (see Table 16). Severity gradings may be reviewed and discussed with the 
participants at the clinic visits. Volunteers will be instructed on how to self-assess the severity of 
these AEs. There will also be space on the diary card to self-document unsolicited AEs, and 
whether medication was taken to relieve the symptoms. 
The severity of clinical adverse events will be assessed by the Investigators according to the 
scales in Tables 16-18. 
Severity grading for laboratory AEs are dependent on the OUH laboratory’s reference and will be 
graded according to the scales in the site-specific table that can be found in the Investigator file. 
These ranges will be based on FDA guidance relative to local laboratory reference ranges [135]. 
CRP may be measured as part of the biochemistry profile for Group 2 on days 0, 1, 3, 7, 56, 57, 59 
and 63. However, CRP results will be used in relation to exploratory immunological analysis only, 
and therefore, any abnormal result will not be considered an AE and grading scales for CRP are 
not listed in the site-specific table, i.e. CRP results will not be considered within the safety 
analysis. 
 
GRADE 0 
None 
GRADE 1 
Mild: Transient or mild discomfort (< 48 hours); no medical 
intervention/therapy required 
GRADE 2 
Moderate: Mild to moderate limitation in activity – some assistance may be 
needed; no or minimal medical intervention/therapy required 
GRADE 3 
Severe: Marked limitation in activity, some assistance usually required; may 
require medical intervention/therapy  
Table 16: Severity grading criteria for AEs. 
 
Physical Observations 
Grade 1 
Grade 2 
Grade 3 
Tachycardia – beats per 
min* 
101-115 
116-130 
>130 

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Hypotension (systolic) 
mm Hg 
85-89 
80-84 
<80 
Hypertension (systolic) 
mm Hg** 
141-159 
160-179 
>180 
Hypertension 
(diastolic) mm Hg** 
91-99 
100-109 
>110 
Fever °C 
37.6 – 38.0 
>38.0 
>39.0 
Table 17: Severity grading criteria for clinically significant abnormal physical observations. All 
observations should be measured at rest. *Only applies when resting heart rate is between 60 
and 100 beats per minute. Use clinical judgement when characterising bradycardia in some 
healthy subject populations (e.g. conditioned athletes). **Systolic or diastolic hypertension may 
only be confirmed as clinically significant (and therefore an AE) if persistently present when 
observations are repeated (i.e. isolated measurements of hypertension are not clinically 
significant). 
 
Adverse Event  
Grade  
Intensity  
Pain at injection site 
1 
Pain that is easily tolerated 
2 
Pain that interferes with daily activity 
3 
Pain that prevents daily activity 
Erythema at injection 
site* 
1 
>3 - ≤50 mm 
2 
>50 - ≤100 mm 
3 
>100 mm 
Swelling at injection site* 
1 
>3 - ≤20 mm 
2 
>20 - ≤50 mm 
3 
>50 mm 
*erythema or swelling ≤3mm is an expected consequence of skin puncture and will therefore not be considered an 
adverse event. 
Table 18: Severity grading criteria for local adverse events. 
12.4.1 Reporting Procedures for Serious AEs (see SOP OVC005 Safety Reporting) 
In order to comply with current regulations on serious adverse event reporting to regulatory 
authorities, the event will be documented accurately and notification deadlines respected. SAEs 
will be reported on the SAE forms to members of the study team immediately after the 

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Investigators become aware of their occurrence, as described in SOP OVC005. Copies of all 
reports will be forwarded for review to the Chief Investigator and Principal Investigators (as the 
Sponsor’s representatives) within 24 hours of the Investigator being aware of the suspected SAE. 
The local safety monitor (LSM) will be notified of SAEs which are deemed possibly, probably or 
definitely related to study interventions; the LSM will be notified immediately (within 24 hours) 
of the Investigators’ being aware of their occurrence. SAEs will not normally be reported 
immediately to the REC unless there is a clinically important increase in occurrence rate, an 
unexpected outcome, or a new event that is likely to affect safety of trial volunteers, at the 
discretion of the Chief Investigator and/or LSM. In addition to the expedited reporting above, the 
Investigator shall include all SAEs in the annual Development Safety Update Report (DSUR) 
report. 
12.4.2 Reporting Procedures for SUSARS 
The Chief Investigator will report all SUSARs to the MHRA and REC within required timelines (15 
days for all SUSARs, unless life threatening in which case 7 days, with a final report within a 
further 8 days (total 15)). The Chief Investigator will also inform all Investigators concerned of 
relevant information about SUSARs that could adversely affect the safety of participants.  
All SUSARs and deaths occurring during the study will be reported to the Sponsor. For all deaths, 
available autopsy reports and relevant medical reports will be made available for reporting to the 
relevant authorities. 
12.4.3 Development Safety Update Report 
A Development Safety Update Report (DSUR) will be submitted by the Chief Investigator to the 
Sponsor, the competent authority and ethics committee on the anniversary of the first approval 
date from the regulatory authority for each IMP. 
12.4.4 Procedures to be followed in the event of abnormal findings 
Eligibility for enrolment in the trial in terms of laboratory findings will be assessed as detailed in 
SOP VC027. Abnormal clinical findings from medical history, examination or blood tests will be 
assessed as to their clinical significance throughout the trial. Laboratory adverse events will be 
assessed using the site-specific tables in the Institutional site file (ISF)/ trial master file (TMF). If a 
test is deemed clinically significant, it may be repeated, to ensure it is not a single occurrence. If a 
test remains clinically significant, the volunteer will be informed and appropriate medical care 
arranged as appropriate and with the permission of the volunteer. Decisions to exclude the 
volunteer from enrolling in the trial or to withdraw a volunteer from the trial will be at the 
discretion of the Investigator. 
12.5 Local Safety Monitor 
An independent Local Safety Monitor (LSM) will be appointed to provide real-time safety 
oversight. The LSM will review SAEs deemed possibly, probably or definitely related to study 
interventions. The LSM will be notified within 24 hours of the Investigators’ being aware of their 
occurrence. The LSM has the power to terminate the study if deemed necessary following a 
study intervention-related SAE. At the time of writing, the LSM will be Prof Brian Angus, a Clinical 
Tutor in Medicine, Honorary Consultant Physician and Director, Centre for Tropical Medicine at 
the University of Oxford. All correspondence between the Investigator and the LSM will be 
conveyed by the Investigator to the trial Sponsor. 

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The LSM may be contacted for advice and independent review by the Investigator or trial 
Sponsor in the following situations: 
 Following any SAE deemed to be possibly, probably, or definitely related to a study 
intervention 
 Any other situation where the Investigator or trial sponsor feels independent advice or 
review is important. 
The study can be put on hold upon advice of the Local Safety Monitor, Chief Investigator, Study 
Sponsor, or Ethical Committee(s), for any single event or combination of multiple events which, 
in their professional opinion, jeopardise the safety of the subjects or the reliability of the data. If 
the study is placed on hold it may only be restarted following discussion with and approval from 
the LSM, the ethics committee(s), the trial Sponsor and Chief Investigator. 
12.6 Safety Stopping/Holding Rules  
Safety holding rules have been developed considering the fact that there is limited experience in 
humans with the ChAd63/MVA PvDBP vaccines and this is the first study to assess P. vivax blood-
stage CHMI following vaccination targeting a blood-stage antigen.  
‘Solicited adverse events’ are those listed as foreseeable adverse reactions in section 12.2.6 of 
the protocol, occurring within the first 7 days after vaccination (day of vaccination and six 
subsequent days). ‘Unsolicited adverse events’ are adverse events other than the foreseeable 
ARs occurring within the first 7 days, or any AEs occurring after the first 7 days after vaccination. 
12.6.1 Group 1 holding rules (applies to further vaccinations in Groups 1 and 2) 
If a Group 1 holding rule is activated, no further vaccinations in any group (Groups 1 and 2) will 
occur until an internal safety review has been conducted and it is deemed appropriate to restart 
dosing. The regulatory authority must be informed of the hold via substantial amendment and a 
request to restart dosing with pertinent data must be submitted as a further, subsequent 
substantial amendment. The internal safety review will consider:  
 The relationship of the AE or SAE to the vaccine or P. vivax CHMI. 
 The relationship of the AE or SAE to the vaccine dose, or other possible causes of the event. 
 If appropriate, additional screening or laboratory testing for other volunteers to identify 
those who may develop similar symptoms, and alterations to the current Participant 
Information Sheet (PIS) are discussed. 
 New, relevant safety information from ongoing research programmes on the various 
components of the vaccine. 
The local ethics committee will also be notified if a holding rule is activated or released.  
All vaccinated volunteers will be followed for safety until resolution or stabilisation (if 
determined to be chronic sequelae) of their AEs. 
 Solicited local adverse events: 
o If vaccine dosing is followed by the same Grade 3 solicited local adverse event beginning 
within 2 days after vaccination (day of vaccination and one subsequent day) and 
persisting at Grade 3 for > 72 hrs in two or more Group 1 volunteers. 

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 Solicited systemic adverse events:  
o If vaccine dosing is followed by the same Grade 3 solicited systemic adverse event 
beginning within 2 days after vaccination (day of vaccination and one subsequent day) 
and persisting at Grade 3 for > 48 hrs in two or more Group 1 volunteers.  
 Unsolicited adverse events: 
o If vaccine dosing is followed by the same Grade 3 unsolicited adverse event (including 
the same laboratory adverse event) that is considered possibly, probably or definitely 
related to vaccination and persists at Grade 3 for > 48 hrs in two or more Group 1 
volunteers.  
 A serious adverse event considered possibly, probably or definitely related to vaccination 
occurs 
12.6.2 Holding criteria for enrolment of Group 2 volunteers (applies to Group 2 only) 
 
If any of the following criteria are activated, then enrolment of Group 2 volunteers will not occur 
until an internal safety review has been conducted and it is deemed appropriate to restart dosing. 
The regulatory authority must be informed of the hold via substantial amendment and a request 
to restart dosing with pertinent data must be submitted as a further, subsequent substantial 
amendment. The holding criteria applying to enrolment of Group 2 volunteers are as follows: 
 
 Solicited systemic adverse events:  
o If two or more volunteers in Group 1 report the same Grade 3 solicited systemic adverse 
, which persists at Grade 3 for > 72 hrs, beginning at any time between CHMI and 
completion of anti-malarial therapy,  
 Unsolicited adverse events: 
o If two or more volunteers in Group 1 develop the same Grade 3 unsolicited adverse 
event, which persists at Grade 3 for >48 hours (including the same laboratory adverse 
event), that is considered possibly, probably or definitely related to CHMI at any time 
between CHMI and completion of anti-malarial therapy  
 A serious adverse event considered possibly, probably or definitely related to CHMI occurs 
 
12.6.3 Groups 2 and 3 vaccination holding rules (applies to Group 2 and 3 only) 
If a Group 2/3 holding rule is activated, then further vaccinations (in Groups 2 and/or 3) will not 
occur until an internal safety review has been conducted and it is deemed appropriate to restart 
dosing. The regulatory authority must be informed of the hold via substantial amendment and a 
request to restart dosing with pertinent data must be submitted as a further, subsequent 
substantial amendment. The internal safety review will consider:  
 The relationship of the AE or SAE to the vaccine or P. vivax CHMI. 
 The relationship of the AE or SAE to the vaccine dose, or other possible causes of the event. 

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 If appropriate, additional screening or laboratory testing for other volunteers to identify 
those who may develop similar symptoms, and alterations to the current Participant 
Information Sheet (PIS) are discussed. 
 New, relevant safety information from ongoing research programmes on the various 
components of the vaccine. 
The local ethics committee will also be notified if a holding rule is activated or released.  
All vaccinated volunteers will be followed for safety until resolution or stabilisation (if 
determined to be chronic sequelae) of their AEs. 
The group holding rules applying to groups 2 and 3 are as follows: 
 Solicited local adverse events: 
o If vaccine dosing is followed by the same Grade 3 solicited local adverse event beginning 
within 2 days after vaccination (day of vaccination and one subsequent day) and 
persisting at Grade 3 for > 72 hrs in >3 Group 2 or 3 volunteers. 
 Solicited systemic adverse events:  
o If vaccine dosing is followed by the same Grade 3 solicited systemic adverse event 
beginning within 2 days after vaccination (day of vaccination and one subsequent day) 
and persisting at Grade 3 for > 48 hrs in >3 Group 2 or 3 volunteers.  
 Unsolicited adverse events: 
o If vaccine dosing is followed by the same Grade 3 unsolicited adverse event (including 
the same laboratory adverse event) that is considered possibly, probably or definitely 
related to vaccination and persists at Grade 3 for > 48 hrs in >3 Group 2 or 3 volunteers.  
 A serious adverse event considered possibly, probably or definitely related to vaccination 
occurs 
 
12.6.4 Individual stopping rules 
In addition to the above stated group holding rules, stopping rules for all individual volunteers 
(Groups 1-3) will apply (i.e., indications to withdraw individuals from further vaccinations). 
 
Local reactions: Injection site ulceration, abscess or necrosis. 
 
Laboratory AEs: 
o The volunteer develops a Grade 3 laboratory adverse event considered possibly, 
probably or definitely related within 7 days after vaccination and persisting 
continuously at Grade 3 for >72hrs. 
 Solicited systemic adverse events:  
o The volunteer develops a Grade 3 systemic solicited adverse event considered possibly, 
probably or definitely related within 2 days after vaccination (day of vaccination and 
one subsequent day) and persisting continuously at Grade 3 for >72hrs.  

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 Unsolicited adverse events:  
o The volunteer has a Grade 3 adverse event, considered possibly, probably or definitely 
related to vaccination, persisting continuously at Grade 3 for >72hrs.  
o The volunteer has a serious adverse event considered possibly, probably or definitely 
related to vaccination. 
o The volunteer has an acute allergic reaction or anaphylactic shock following the 
administration of the vaccine investigational product. 
If a volunteer has an acute illness (moderate or severe illness with or without fever) or a fever (oral 
temperature greater than 37.5°C) at the scheduled time of administration of investigational 
product, the volunteer will not receive the vaccine at that time. The vaccine may be administered 
to that volunteer at a later date within the time window specified in the protocol (see Table 8) or 
they may be withdrawn from the study at the discretion of the Investigator.  
All vaccinated volunteers will be followed for safety until the end of their planned participation in 
the study or until resolution or stabilisation (if determined to be chronic sequelae) of their AEs, 
providing they consent to this.  
In addition to these pre-defined criteria, the study can be put on hold upon advice of the Local 
Safety Monitor, Chief Investigator, Study Sponsor, regulatory authority, Research Ethics 
Committee (REC) or Local Safety Monitor (LSM), for any single event or combination of multiple 
events which, in their professional opinion, jeopardise the safety of the volunteers or the 
reliability of the data. 
 

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13 STATISTICS 
13.1  Sample size 
This is an open label, Phase IIa single site controlled human malaria infection study, aiming to 
assess efficacy of the ChAd63 PvDBP and MVA PvDBP vaccine candidates against blood-stage 
challenge for the first time, utilising a newly produced cryopreserved inoculum source. The 
number of volunteers undergoing vaccination, followed by malaria challenge will be a total of 15. 
Three volunteers will receive prime-boost vaccination followed by blood-stage challenge as a 
preliminary study. Provided there are no safety concerns following challenge in this lead-in 
group, the remaining 10-12 will then undergo the same vaccination regimen followed by CHMI.  
Outcome measures will be assessed as described in Section 7. PMR will constitute the primary 
endpoint for the study and pooled data for PMR will be compared with PMR in 15 malaria-naïve 
infectivity controls, recruited as part of another study, VAC069, who will undergo CHMI in 
parallel with Groups 1 and 2 (3 controls will be challenged in parallel with Group 1 and 12 
additional controls will be challenged at the same time as Group 2). Any statistically significant 
change in PMR in a vaccine group would be considered as success, however, it is not clear what 
level of change in PMR would be likely to be significant in terms of clinical outcome.  
Statistical power calculations for previous trials assessing P. falciparum blood-stage candidates in 
Oxford have determined that power is heavily dependent upon the assumptions made regarding 
the distribution of data in controls, and the effect of the intervention upon both the location and 
dispersion of data in the intervention group. This study will be only the second time this source 
of cryopreserved parasitised erythrocytes (as described in full in Section 5.2) has been utilised for 
blood-stage CHMI. Data from the pilot study, VAC069, which will determine safety, feasibility and 
optimal inoculation dose in January 2019, is not yet available. Therefore, currently neither the 
mean PMR nor distribution of PMRs in controls are yet established.  
Due to variation in data in previously conducted P. falciparum blood-stage challenge trials 
conducted in Oxford [130, 131] and in Nijmegen (RUNMC) in both mean PMR and standard 
deviation of PMR among controls, a number of scenarios were modelled to determine power 
≥80% to detect a either a 33% or 50% reduction in mean PMR in vaccinated subjects relative to 
controls in each circumstance, for a P. falciparum candidate vaccine. The historical mean PMR in 
P. falciparum challenge trials Oxford had been 12-fold per 48 hours, and at RUNMC had been 10-
fold. The statistical power of studies with a variety of group sizes up to a maximum total number 
of volunteers of 30, based upon clinical trial site capacity, were calculated for the below: 
10 controls (N1) vs 10 vaccinees (N2) 
10 controls (N1) vs 20 vaccinees (N2) 
15 controls (N1) vs 15 vaccinees (N2) 
A number of scenarios with various values of these parameters were modelled, as follows: 
 Three possible values for SD of the PMR in the control group: 2, 3 and 4-fold per 48 hours, 
based upon the extremes of observed data from Oxford and RUNMC. 
 Three possible values for SD of the vaccine effect upon PMR– currently unknown. We 
used estimates of 2, 3 and 4-fold per 48 hours.  
Thus a total of 9 possible scenarios (combinations of PMR SD in the control group and vaccine 
effect PMR) were considered for each combination of mean vaccine efficacy (33 v 50%), group 
size, and underlying PMR in controls. Power calculations were performed using a two-sample 

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two-sided t-test power analysis by Dr Nicola Williams at the Centre for Statistics in Medicine in 
Oxford in consultation with the group at the Jenner Institute. 
All three options for group sizes were calculated to provide sufficient power to detect a 50% 
reduction in PMR – irrespective of whether analysis was based on historical data from Oxford or 
RUNMC. However, small differences in the dispersion of PMR between the two groups had a 
major impact on power of studies with smaller numbers of volunteers in the control groups, such 
that it was not possible to be confident that trials with 10 controls would be adequately powered 
to detect a 33% vaccine effect upon PMR. A study design with 15 controls versus 15 vaccinees 
consistently did, however, provide adequate power to detect a 33% vaccine effect upon PMR 
under most circumstances, including those with relatively high dispersion of PMR in the controls 
and/or high dispersion of vaccine efficacy (as shown in Table 19).  
A study design with 15 controls vs 15 vaccinees was therefore chosen for the VAC054 P. 
falciparum blood-stage challenge and will be mirrored in this study. Given no prior data exists, 
modelling of the above scenarios may not be applicable to P. vivax blood-stage challenge, 
however, the required sample size to give statistical power to detect either a 33% or 50% PMR 
will be calculated once further PMR data is available for malaria-naïve controls undergoing 
challenge in this model. Of note, smaller numbers are routinely studied and reported in 
numerous other CHMI trials, undertaken in Oxford and elsewhere. 
 
Number of scenarios under which power ≥80% to detect a 33% 
reduction in mean PMR * 
Group Size 
Oxford data (mean 
control PMR = 12) 
RUNMC data (mean 
control PMR = 10) 
Total 
10 vs 10 
4/9 
1/9 
5/18 
10 vs 20 
6/9 
4/9 
10/18 
15 vs 15 
8/9 
4/9 
12/18 
Table 19: Scenarios tested for power calculations for blood-stage P. falciparum CHMI 9 
scenarios for underlying SD in the controls and vaccinees in blood-stage P. falciparum CHMI were 
assessed for each combination of group size, underlying PMR in control groups, and vaccine 
effect; data shown here relate to the lower level of vaccine efficacy considered, i.e. 33% PMR 
reduction. A key comparison is the power of a 10 vs 10 trial as compared to a 15 vs 15 trial to 
detect a 33% reduction in PMR. The former gives ≥80% power under 5/18 tested situations; the 
latter gives ≥80% power under 12/18 scenarios. 
 
 
 
 

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14 QUALITY CONTROL AND QUALITY ASSURANCE PROCEDURES 
14.1  Investigator procedures 
Approved site-specific SOPs will be used at all clinical and laboratory sites. 
14.2 Monitoring 
Monitoring will be performed by CTRG using established procedures, according to ICH Good 
Clinical Practice (GCP).  Following written standard operating procedures, the monitors will verify 
that the clinical trial is conducted and data are generated, documented and reported in 
compliance with the protocol and GCP. The sites will provide direct access to all trial related 
source data/documents and reports for the purpose of auditing by the Sponsor and inspection by 
local and regulatory authorities. 
14.3 Modification to protocol 
No substantial amendments to this protocol will be made without consultation with, and 
agreement of, the Sponsor. Any substantial amendments to the trial that appear necessary 
during the course of the trial must be discussed by the Investigator and Sponsor concurrently. If 
agreement is reached concerning the need for an amendment, it will be produced in writing by 
the Chief Investigator and will be made a formal part of the protocol following ethical approval. 
The Investigator is responsible for ensuring that changes to an approved trial, during the period 
for which ethical committee(s) approval has already been given, are not initiated without ethical 
committee(s)’ review and approval except to eliminate apparent immediate hazards to the 
subject. 
14.4 Protocol deviation  
Any deviations from the protocol will be documented in a protocol deviation form and filed in 
the site trial master file.  
14.5 Audit & inspection  
The QA manager performs system based internal audits to check that  trials are being conducted, 
data recorded, analysed and accurately reported according to study protocols, departmental 
SOPs and in compliance with ICH GCP. The audit schedule includes laboratory activities. The 
internal audits will supplement the external monitoring process and will review processes not 
covered by the external monitor. 
The Sponsor, trial sites, ethical committee(s), and authorised individuals may carry out audit to 
ensure compliance with the protocol, GCP and appropriate regulations. GCP inspections may also 
be undertaken by the regulatory authority to ensure compliance with protocol and national 
regulations. The Sponsor will assist in any inspections. 
14.6 Serious breaches 
A serious breach is defined as “A breach of GCP or the trial protocol which is likely to effect to a 
significant degree –  
(a) the safety or physical or mental integrity of the subjects of the trial; or 
(b) the scientific value of the trial. 
In the event that a serious breach is suspected the Sponsor must be contacted within 1 working 
day. In collaboration with the CI the serious breach will be reviewed by the Sponsor and, if 

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appropriate, the Sponsor will report it to the REC committee, Regulatory authority and the 
relevant NHS host organisation within seven calendar days. 
12.7 Trial progress 
The progress of the trial will be overseen by the Chief Investigator. 
12.8 Publication policy 
The Investigators will be involved in reviewing drafts of the manuscripts, abstracts, press releases 
and any other publications arising from the study.  Authorship will be determined in accordance 
with the ICMJE guidelines and other contributors will be acknowledged. Data may also be used 
for a PhD or MD thesis.  
12.9 Intellectual Property 
Ownership of intellectual property (IP) generated by employees of the University vests in the 
University.  The protection and exploitation of any new IP is managed by the University’s 
technology transfer office, Oxford University Innovations 

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13 ETHICS 
13.1 Declaration of Helsinki 
The Investigator will ensure that this study is conducted according to the principles of the current 
revision of the Declaration of Helsinki 2008. 
13.2 Guidelines for good clinical practice 
The Investigator will ensure that this trial is conducted in accordance with relevant regulations 
and with Good Clinical Practice. 
13.3 Approvals 
Following Sponsor approval the protocol, informed consent form, participant information sheet 
and the proposed advertising material will be submitted to an appropriate Research Ethics 
Committee (REC), HRA (where required), regulatory authorities (MHRA in the UK), and host 
institution(s) for written approval. 
The Investigator will submit and, where necessary, obtain approval from the above parties for all 
substantial amendments to the original approved documents. 
13.4 
Reporting  
The CI shall submit once a year throughout the study, or on request, an Annual Progress Report 
to the REC, HRA (where required), host organisation and Sponsor. In addition, an End of Study 
notification and final report will be submitted to the REC and Sponsor. 
13.5 Volunteer confidentiality 
All data will be anonymised; volunteer data will be identified by a unique study number in the 
CRF and database. Separate confidential files containing identifiable information will be stored in 
secured locations. Only the Sponsor representative, Investigators, the clinical monitor, the 
ethical committee(s) and the regulatory authorities will have access to the records. Photographs 
taken (if required, with the volunteer’s written, informed consent) will not include the 
volunteer’s face and will be identified by the volunteer’s trial specific identification number only. 
Once developed, photographs will be stored as confidential records, as above. This material may 
be shown to other professional staff, used for educational purposes, or included in a scientific 
publication.  
Results of any COVID-19 swab tests carried out through this study will be legally required to be 
reported to Public Health England. Along with the result of the COVID-19 test, the following 
details will also reported: personal details of the participant (name, date of birth, contact details, 
ethnicity, NHS number) and date of diagnosis and symptom onset if applicable. 

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14 DATA HANDLING AND RECORD KEEPING 
14.1 Data handling 
The Chief Investigator will be the data manager with responsibility for delegating the receiving, 
entering, cleaning, querying, analysing and storing all data that accrues from the study. Data will 
be entered into the volunteers’ CRFs in a paper and/or electronic format (using the OpenClinica™ 
database). Electronic data will be stored on secure servers which are outsourced by 
OpenClinica™. OpenClinica™ meets FDA part 11B standards. This includes safety data, laboratory 
data and outcome data. Data are entered in a web browser on PCs and then transferred to the 
OpenClinica Database by encrypted (https) transfer. Safety data will also be collected through an 
electronic diary, which is stored on a secure server.  
14.2 Record keeping 
The Investigators will maintain and retain appropriate medical and research records and 
essential documents for this trial in compliance with ICH E6 GCP and regulatory and institutional 
requirements for the protection of confidentiality of volunteers. The Chief Investigator, co-
investigators, clinical research nurses and authorised personnel will have access to records. The 
investigators will permit authorised representatives of the Sponsor, ethical committee(s), 
regulatory agencies, and the monitors to examine (and when required by applicable law, to copy) 
clinical records for the purposes of quality assurance reviews, audits and evaluation of the study 
safety and progress. 
14.3 Source data and electronic case report forms (eCRFs) 
All protocol-required information will be collected in the electronic diaries and eCRFs designed 
by the Investigator. All source documents will be filed in the participants’ notes. Source 
documents are original documents, data, and records from which the volunteer’s eCRF data are 
obtained. For this study these will include, but are not limited to; volunteer consent form, blood 
results, GP response letters, laboratory records and correspondence. In the majority of cases, 
electronic diaries and eCRF entries will be considered source data as these are the site of the 
original recording (i.e. there is no other written or electronic record of data). In this study this will 
include, but is not limited to medical history, medication records, vital signs, physical 
examination records,  adverse event data and details of study interventions. All source data and 
volunteer CRFs will be stored securely. 
14.4 Data protection  
The study protocol, documentation, data and all other information generated will be held in 
strict confidence. No information concerning the study or the data will be released to any 
unauthorised third party, without prior written approval of the Sponsor. 
Results of any COVID-19 swab tests carried out through this study will be legally required to be 
reported to Public Health England. Along with the result of the COVID-19 test, the following 
details will also reported: personal details of the participant (name, date of birth, contact details, 
ethnicity, NHS number) and date of diagnosis and symptom onset if applicable. 
 

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15 FINANCING AND INSURANCE 
15.1 Financing 
The study is funded through MultiViVax, a European Commission Horizon 2020 funded project 
which intends to develop a highly effective multi-stage malaria vaccine to the point of proof-of-
concept Phase II testing in Europe, prior to clinical trials in malaria-endemic areas. 
15.2 Insurance 
The University has a specialist insurance policy in place which would operate in the event of any 
participant suffering harm as a result of their involvement in the research (Newline Underwriting 
Management Ltd, at Lloyd’s of London). NHS indemnity operates in respect of the clinical 
treatment that is provided. 
15.3 Compensation 
Volunteers will be compensated for their time and for the inconvenience caused by procedures 
as below.   
- Screening visit  
 
 
 
 
 
 
£25  
Subsequent visits: 
- Travel expenses 
 
 
 
 
 
 
£15 per visit 
- Inconvenience of blood tests: 
 
 
 
 
£10 per blood donation 
- Time required for visit: 
 
 
 
 
 
£20 per hour 
- Admission (Illness) Compensation                                                  
£480 total 
Where travel expenses are greater than £15 per visit because the volunteer lives outside the city 
of the trial site, the volunteer may be given further reimbursement to meet the cost of travel 
necessary for study visits at the Investigator’s discretion. The backup volunteer who does not 
undergo malaria challenge will be compensated £200 in addition to compensation for visits they 
may have attended. 
 
Table 20:  Estimated compensation amounts. 
 
Time in Trial
(approx.) 
Maximum No. of 
Visits 
Maximum Volume of 
Blood Taken (mL) 
Compensation 
Group 1 
1 year 
60 
1329 
£3320 
Group 2 
2 years 
53 
1387 
£2990 
Group 3 
1 year 
47 
1151 
£2690 

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16 APPENDICES 
Appendix A: laboratory values for exclusion 
Laboratory parameters for inclusion/exclusion in the trial will be considered on an individual 
basis, with Investigator discretion for interpretation of results and the need for repeated or 
further tests. In general, volunteers will be excluded if a result at screening constitutes what 
would qualify as a grade 1 (or higher) laboratory adverse event, according to the laboratory 
adverse event tables (filed in the TMF), on repeat of an abnormal test result. Urinalysis at 
screening will be assessed as per the table below: 
 
URINE ANALYSIS (using MULTISTIX) 
Protein* 
2+ or Protein creatinine ratio of ≥ 50 mg/mmol 
Blood£ 
2+ on two dipstick tests  
Glucose 
1+ 
Table 21: Urinalysis assessment.  
*In the event of the dipstick testing positive for protein with ≥1+ protein urine should be sent for 
a protein creatinine ratio. 
£ In the event of urine dipstick testing positive for ≥1+ blood with, or without, protein, a repeat 
dipstick test will be carried out to confirm haematuria. In female volunteers, a menstrual history 
will be taken to elicit whether the subject is currently menstruating and if they are, urine dipstick 
will be repeated after 1 - 2 weeks. If blood and/or proteinuria persist in any volunteer, an 
interpretation of the results will be undertaken by the Investigator on an individual basis to 
determine if they will be excluded from the trial, and the appropriate follow-up arranged. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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