A Phase 1, 2-part, Open-label, Fixed-sequence Study Evaluating the Effect of Rifampin (Part 1) and Rabeprazole (Part 2) on the Pharmacokinetics of a Single Dose of Camlipixant (BLU-5937) 50 mg Tablet in Healthy Participants Under Fasting Conditions
Phase: PHASE1
Conditions: Cough, Healthy
Sponsor: Bellus Health Inc. - a GSK company

Protocol
Study ID:  221853
Official Title of Study: A PHASE 1, 2-PART, OPEN-LABEL, 
FIXED-SEQUENCE STUDY EVALUATING THE EFFECT OF 
RIFAMPIN (PART 1) AND RABEPRAZOLE (PART 2) ON THE 
PHARMACOKINETICS OF A SINGLE DOSE OF CAMLIPIXANT 
(BLU-5937) 50 mg TABLET IN HEALTHY PARTICIPANTS UNDER 
FASTING CONDITIONS
Date of Document: 20 Jul 2023

The GlaxoSmithKline group of companies 
Clinical Study Report 
Study Protocol Number: 220254 (BUS-P1-11) 
Page 1 of 4 
16.1.1 
Protocol and Protocol Amendments 
Table of contents 
16.1.1 
Protocol and Protocol Amendments ........................................................ 1 
Table of contents ................................................................................................................. 1 
Study Final Protocol 1.0 dated 03-APR-2023 ..................................................................... 2 
Protocol Administrative Letter dated 13-JUN-2023 ......................................................... 70 
Protocol Administrative Letter dated 20-JUL-2023 .......................................................... 73 

The GlaxoSmithKline group of companies 
 
Clinical Study Report 
 
 
Study Protocol Number: 220254 (BUS-P1-11) 
 
 
Page 2 of 4 
 
Study Final Protocol 1.0 dated 03-APR-2023

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PROTOCOL 220254 
Bellus Health study number: BUS-P1-11 
 
A PHASE 1, 2-PART, OPEN-LABEL, FIXED-SEQUENCE STUDY EVALUATING THE 
EFFECT OF RIFAMPIN (PART 1) AND RABEPRAZOLE (PART 2) ON THE 
PHARMACOKINETICS OF A SINGLE DOSE OF CAMLIPIXANT (BLU-5937) 50 mg 
TABLET IN HEALTHY PARTICIPANTS UNDER FASTING CONDITIONS 
 
Sponsor: 
Bellus Health 
275 Armand-Frappier Blvd. 
Laval, Quebec 
Canada, H7V 4A7 
Tel.: 450 680 4500 
 
Contract Research 
Organization: 
Protocol Version: 
Final 
Date: 
03-APR-2023 
CONFIDENTIAL 
 
This document is strictly confidential. It was developed for Bellus Health by 
. The information in this 
document may be disclosed only to persons involved in the study, ethics committees, regulatory agencies and study 
audit personnel. This document is copyrighted in favor of 
 and cannot be reproduced, modified, or 
adapted, in part or in total, without prior written approval by 
. 
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Protocol Historical File 
Version 
Brief description/summary of changes 
Date 
Final 
Version submitted to the Independent Ethics Committee (IEC). 
03-APR-2023 

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Sponsor Signature Page
Bellus Health Cough Inc.
275 Armand-Frappier Blvd.
Laval, Quebec
Canada H7V 4A7
Tel.: (450) 680-4500
s:
______________________
Dr. Denis Garceau, Ph.D.
Date
Chief Scientific Officer
_________________
______________________
Nathalie Chauret, M.Sc.
Date
Executive Director, Head of Drug Development
______
______________________
Sarabjit Gahir, BPharm, Ph.D.
Date
Director of Clinical Pharmacology
PPD
PPD
PPD
PPD
PPD
PPD

PPD
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Facilities and Responsible Staff 
Clinical Research Facilities 
This study will be conducted by 
 at the following facility: 
Screening and/or visits may also be performed at the 
 facility: 
Biomedical Laboratory Facilities 
Biomedical laboratory testing will be performed by the following laboratories: 
If another biomedical laboratory is used, this will be documented and annexed to the protocol. 
 
 
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Manager Bioanalysis, Clinical Pharmacology and Bioanalysis 
Institutional Review Board 
Advarra Aurora, Ontario, Canada 
372 Hollandview Trail, Suite 300 
Aurora, Ontario, Canada L4G 0A5 
Tel.: 1-905-727-7989 
 
 
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Table of Contents 
PROTOCOL HISTORICAL FILE ............................................................................................. 2 
SPONSOR SIGNATURE PAGE ................................................................................................. 3 
INVESTIGATOR SIGNATURE PAGE..................................................................................... 4 
FACILITIES AND RESPONSIBLE STAFF ............................................................................. 5 
CLINICAL RESEARCH FACILITIES.................................................................................................................................... 5 
BIOMEDICAL LABORATORY FACILITIES ......................................................................................................................... 5 
CLINICAL PHARMACOLOGY AND BIOANALYSIS ............................................................................................................. 5 
BIOANALYTICAL FACILITY ............................................................................................................................................. 5 
INSTITUTIONAL REVIEW BOARD .................................................................................................................................... 6 
TABLE OF CONTENTS ............................................................................................................. 7 
LIST OF TABLES AND FIGURES ............................................................................................ 9 
LIST OF ABBREVIATIONS .................................................................................................... 10 
SYNOPSIS OF PROTOCOL .................................................................................................... 13 
1. 
INTRODUCTION ............................................................................................................. 26 
1.1 
BACKGROUND INFORMATION............................................................................................................................ 26 
1.2 
NONCLINICAL ................................................................................................................................................... 26 
1.3 
CLINICAL .......................................................................................................................................................... 27 
1.4 
BACKGROUND INFORMATION ON RIFAMPIN ...................................................................................................... 28 
1.5 
BACKGROUND INFORMATION ON RABEPRAZOLE .............................................................................................. 29 
1.6 
STUDY RATIONALE ........................................................................................................................................... 30 
1.7 
BENEFIT/RISK ASSESSMENT .............................................................................................................................. 34 
2. 
OBJECTIVES .................................................................................................................... 35 
3. 
ENDPOINTS ...................................................................................................................... 35 
4. 
STUDY DESIGN ............................................................................................................... 35 
5. 
STUDY POPULATION .................................................................................................... 38 
5.1 
NUMBER OF PARTICIPANTS ............................................................................................................................... 38 
5.2 
INCLUSION CRITERIA ........................................................................................................................................ 38 
5.3 
EXCLUSION CRITERIA ....................................................................................................................................... 39 
5.4 
PARTICIPANT WITHDRAWAL AND REPLACEMENT ............................................................................................. 41 
6. 
STUDY TREATMENTS .................................................................................................. 41 
6.1 
DRUG SUPPLIES AND ACCOUNTABILITY ............................................................................................................ 41 
6.2 
IDENTIFICATION OF TREATMENTS ..................................................................................................................... 42 
6.3 
RANDOMIZATION AND BLINDING ...................................................................................................................... 42 
6.4 
STUDY DRUG ADMINISTRATION ....................................................................................................................... 42 
7. 
STUDY RESTRICTIONS ................................................................................................ 44 
7.1 
CONCOMITANT MEDICATIONS .......................................................................................................................... 44 
7.2 
DRUGS, NICOTINE AND ALCOHOL ..................................................................................................................... 44 
7.3 
DIET .................................................................................................................................................................. 44 
7.4 
POSTURE AND PHYSICAL ACTIVITY .................................................................................................................. 45 
8. 
STUDY PROCEDURES ................................................................................................... 45 
8.1 
PHARMACOKINETIC ASSESSMENTS ................................................................................................................... 46 
8.2 
PHARMACOGENOMIC ASSESSMENTS ................................................................................................................. 47 

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8.3 
SAFETY AND TOLERABILITY ASSESSMENTS ...................................................................................................... 47 
8.4 
ADVERSE EVENTS AND SERIOUS ADVERSE EVENTS ......................................................................................... 50 
8.5 
PREMATURE TERMINATION OF THE STUDY ....................................................................................................... 54 
9. 
STATISTICAL ANALYSES ............................................................................................ 54 
9.1 
ANALYSIS POPULATIONS................................................................................................................................... 54 
9.2 
PHARMACOKINETIC PARAMETERS .................................................................................................................... 55 
9.3 
PHARMACOKINETIC STATISTICAL ANALYSIS .................................................................................................... 56 
9.4 
CRITERIA FOR NO DRUG-DRUG INTERACTION FOR CAMLIPIXANT .................................................................... 56 
9.5 
SAFETY AND TOLERABILITY ANALYSIS ............................................................................................................ 56 
9.6 
PHARMACOGENOMIC EVALUATION ................................................................................................................... 57 
10. 
DATA COLLECTION ...................................................................................................... 57 
11. 
REGULATORY CONSIDERATIONS AND QUALITY ASSURANCE .................... 57 
11.1 
IEC APPROVAL OF PROTOCOL AND OTHER STUDY DOCUMENTS ...................................................................... 57 
11.2 
COMPLIANCE..................................................................................................................................................... 58 
11.3 
QUALITY ASSURANCE AND MONITORING ......................................................................................................... 58 
11.4 
CONFIDENTIALITY AND RETENTION OF STUDY RECORDS ................................................................................. 58 
12. 
REFERENCES .................................................................................................................. 60 
13. 
APPENDIX 1 ..................................................................................................................... 62 
14. 
APPENDIX 2 ..................................................................................................................... 66 
 

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List of Tables and Figures 
TABLE 1. 
SCHEDULE OF ASSESSMENTS FOR PART 1 .................................................................. 20 
TABLE 2. 
SCHEDULE OF ASSESSMENTS FOR PART 2 .................................................................. 23 
FIGURE 1. STUDY DESIGN DIAGRAM FOR PART 1 .......................................................................... 36 
FIGURE 2. STUDY DESIGN DIAGRAM FOR PART 2 .......................................................................... 37 
TABLE 3. 
TIME WINDOWS FOR PK BLOOD SAMPLES FOR PART 1 ............................................. 46 
TABLE 4. 
TIME WINDOWS FOR PK BLOOD SAMPLES FOR PART 2 ............................................. 46 
TABLE 5. 
CLINICAL LABORATORY ASSESSMENTS ..................................................................... 49 
TABLE 6. 
SEVERITY SCALE ....................................................................................................... 51 
TABLE 7. 
RELATIONSHIP CATEGORIES ...................................................................................... 52 

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List of Abbreviations 
AD 
atopic dermatitis 
ADAM 
advanced dissolution, absorption, and metabolism 
AE 
adverse event 
AEMI 
adverse event of medical interest 
ALT 
alanine aminotransferase 
ANOVA 
analysis of variance 
aPTT 
activated partial thromboplastin time 
AST 
aspartate aminotransferase 
ATP 
adenosine triphosphate 
AUC0-inf 
area under the concentration-time curve from time zero to infinity 
(extrapolated) 
AUC0-t 
area under the concentration-time curve from time zero until the last 
observed concentration 
BCRP 
breast cancer resistance protein 
BID 
bis in die (twice a day) 
BMI 
body mass index 
BUN 
blood urea nitrogen 
CDER 
Center for Drug Evaluation and Research 
CFR 
Code of Federal Regulations 
CI 
confidence interval 
CK 
creatine kinase 
Cl/F 
apparent clearance 
Cmax 
maximal observed concentration 
COVID-19 
coronavirus 2019 
CRF 
case report form 
CRO 
contract research organization 
CTA 
Clinical Trial Application 
CV 
coefficient of variation 
CYP 
cytochrome P450 
DDI 
drug-drug interaction 
DMP 
data management plan 
DNA 
deoxyribonucleic acid 
eCRF 
electronic case report form 
ECG 
electrocardiogram 
EFD 
embryo-fetal development 

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ET 
early termination 
FDA 
Food and Drug Administration 
FIH 
first-in-human 
fm 
fraction metabolized 
FSH 
follicle-stimulating hormone 
GCP 
Good Clinical Practice 
GERD 
gastroesophageal reflux disease 
GGT 
gamma-glutamyl transferase 
GMP 
Good Manufacturing Practice 
HBsAg 
hepatitis B surface antigen 
HCV 
hepatitis C virus 
HEENT 
head, eyes, ears, nose, and throat 
HIV 
human immunodeficiency virus 
IB 
Investigator’s Brochure 
IBS 
irritable bowel syndrome 
ICF 
informed consent form 
ICH 
International Council for Harmonisation of Technical Requirements for 
Pharmaceuticals for Human Use 
IEC 
Independent Ethics Committee 
IME 
important medical event 
INR 
international normalized ratio 
Kel 
terminal elimination rate constant 
LFT 
liver function test 
LS 
least squares 
MAD 
multiple ascending dose 
Max 
maximum 
MDMA 
3,4-methylenedioxymethamphetamine 
MedDRA 
Medical Dictionary for Regulatory Activities 
Min 
minimum 
NERD 
non erosive reflux disease 
NOAEL 
no observed adverse effect level 
NOEL 
no observed effect level 
NOL 
No Objection Letter 
OATP 
organic anion transporter polypeptide 
OTC 
over-the-counter 
PBPK 
physiologically based pharmacokinetic 

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PC 
pharmacokinetic concentration 
PCP 
phencyclidine 
PEPT1 
peptide transporter 1 
PK 
pharmacokinetic(s) 
PPI 
proton-pump inhibitor 
PT 
prothrombin time 
QA 
quality assurance 
QC 
quality control 
QT 
QT interval 
QTcF 
Fridericia’s corrected QT interval 
RBC 
red blood cell 
RCC 
refractory and unexplained chronic cough 
RNA 
ribonucleic acid 
SAD 
single ascending dose 
SAE 
serious adverse event 
SAP 
statistical analysis plan 
SAS 
statistical analysis system 
SD 
standard deviation 
SOP 
standard operation procedure 
SUSAR 
suspected, unexpected, serious adverse reaction 
T½ el 
terminal elimination half-life 
TDAE 
taste disturbance adverse event 
TEAE 
treatment-emergent adverse event 
THC 
tetrahydrocannabinol 
Tmax 
time when the maximal concentration is observed 
 
 
ULN 
upper limit of normal 
Vz/F 
apparent volume of distribution 
WBC 
white blood cell 
WHODrug 
World Health Organization Drug 
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Synopsis of Protocol 
Project Number: 
220254 
BUS-P1-11 
Title: 
A Phase 1, 2-Part, Open-label, Fixed-sequence Study Evaluating the Effect 
of Rifampin (Part 1) and Rabeprazole (Part 2) on the Pharmacokinetics of a 
Single Dose of Camlipixant (BLU-5937) 50 mg Tablet in Healthy 
Participants under Fasting Conditions 
Investigational 
Product: 
Camlipixant (BLU-5937) 50 mg Tablet 
Study Phase and Type: 
Phase 1 – Drug-Drug Interaction (DDI) 
Objectives: 
Primary objectives: 
• 
To assess the effect of repeated oral doses of rifampin, a cytochrome 
P450 (CYP) 3A4 and 
 inducer (Part 1), or rabeprazole, a 
proton-pump inhibitor (PPI) (Part 2), on the pharmacokinetics (PK) of a 
single oral dose of camlipixant (BLU-5937), administered to healthy 
participants. 
Secondary objective: 
• 
To evaluate the safety and tolerability of camlipixant when 
administered alone and in combination with rifampin or rabeprazole to 
healthy participants. 
Endpoints: 
Primary endpoints: 
• 
PK parameters: AUC0-inf, AUC0-t, and Cmax 
Secondary endpoints: 
• 
PK parameters: Tmax, T½ el, Residual area, Kel, Cl/F, and Vz/F 
• 
Safety evaluation: 
o Adverse events (AEs), serious adverse events (SAEs), adverse 
events of medical interest (AEMIs), vital signs measurements 
(blood pressure, heart rate, respiratory rate, and oral temperature), 
12-lead electrocardiogram (ECG) recordings, physical 
examinations, and clinical laboratory test results, including 
hematology, biochemistry, coagulation, and urinalysis. 
Study Design: 
This is a single-center, 2-part, Phase 1, open-label, fixed-sequence, DDI 
study designed to compare the PK of camlipixant when administered with 
and without rifampin (Part 1) or rabeprazole (Part 2) in healthy participants 
under fasting conditions. The start of study conduct for Part 2 is 
independent from Part 1 study conduct. 
Participants will be enrolled to either Part 1 or Part 2. In each part, 
participants will receive the assigned treatment. 
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In Part 1, participants will receive a single oral dose of 1 x 50 mg 
camlipixant tablet on Day 1, followed by 48 hours of PK and safety 
assessments. Repeated oral doses of 
 mg rifampin capsules (total 
dose 
mg) will be administered 
 on Days 4 to 12, with 
co-administration of a single oral dose of 1 x 50 mg camlipixant tablet with 
rifampin capsules on Day 11. Administration of camlipixant on Day 11 will 
occur 1 hour (± 2 minutes) after administration of rifampin, followed by 
48 hours of PK and safety assessments. 
In Part 2, participants will receive a single oral dose of 1 x 50 mg 
camlipixant tablet on Day 1, followed by 48 hours of PK and safety 
assessments. Repeated oral doses of 
 mg rabeprazole enteric-coated 
tablets will be administered 
 on Days 4 to 11, with co-administration of 
a single oral dose of 1 x 50 mg camlipixant tablet with rabeprazole 
enteric-coated tablet on Day 10. Administration of camlipixant on Day 10 
will occur 1 hour (± 2 minutes) after administration of rabeprazole, 
followed by 48 hours of PK and safety assessments. 
The study will include a screening visit from Day -28 to Day -1. In each 
part of the study, eligible participants will be admitted to the clinical site on 
Day -1 and will be confined until completion of the assessments on Day 13 
(Part 1) or Day 12 (Part 2). There will be a washout period of at least 3 days 
between the first dose of camlipixant on Day 1 and the first dose of 
rifampin (Part 1) or rabeprazole (Part 2) on Day 4. A follow-up phone call 
will be performed 7 ± 2 days after discharge (Day 20 ± 2 in Part 1 and 
Day 19 ± 2 in Part 2). 
Study Population: 
A total of 32 healthy participants are planned to be enrolled. Participants 
must be ≥ 18 and ≤ 55 years of age and non-smoker for enrollment in the 
study. In Part 1, a total of 16 healthy males and non-childbearing potential 
females will be enrolled. In Part 2, a total of 16 healthy males and females 
will be enrolled. 
Inclusion/Exclusion 
Criteria: 
Inclusion Criteria: 
1. Male (Parts 1 and 2) or non-childbearing potential female (Part 1) or 
female (Part 2), non-smoker (no use of tobacco or nicotine products 
within 3 months prior to screening), ≥18 and ≤55 years of age, with 
BMI >18.5 and <30.0 kg/m2 and body weight ≥50.0 kg for males and 
≥45.0 kg for females. 
2. Healthy as defined by: 
a. the absence of clinically significant illness and surgery within 
4 weeks prior to dosing. 
b. the absence of clinically significant history of neurological, 
endocrine, cardiovascular, respiratory, hematological, 
immunological, psychiatric, gastrointestinal, renal, hepatic, and 
metabolic disease. 
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3. Female participants of non-childbearing potential (Part 1 and Part 2) 
must be: 
a. post-menopausal (spontaneous amenorrhea for at least 12 months 
prior to dosing) with confirmation by documented FSH levels 
≥40 mIU/mL; or 
b. surgically sterile (bilateral oophorectomy, bilateral salpingectomy, 
or hysterectomy) at least 3 months prior to dosing. 
4. Female participants of childbearing potential (Part 2 only) who are 
sexually active with a non-sterile male partner (sterile male partners are 
defined as men vasectomized for at least 3 months prior to dosing) must 
be willing to use one of the following acceptable contraceptive methods 
throughout the study and for 30 days after the last dose: 
a. simultaneous use of non-hormonal intrauterine device placed at 
least 4 weeks prior to dosing and condom for the male partner; 
b. simultaneous use of diaphragm or cervical cap with spermicide and 
condom for the male partner, started at least 21 days prior to 
dosing; 
c. tubal ligation at least 3 months prior to dosing. 
5. Female participants must be willing not to donate ova for 30 days after 
the last dose. 
6. Male participants who are not vasectomized for at least 3 months prior 
to dosing and who are sexually active with a female partner of 
childbearing potential must be willing to use one of the following 
acceptable contraceptive methods from the first dose and for 90 days 
after the last dose: 
a. simultaneous use of condom and hormonal contraceptive (e.g., oral, 
patch, depot injection, implant, vaginal ring, intrauterine device) or 
non-hormonal intrauterine device used for at least 4 weeks prior to 
sexual intercourse for the female partner; 
b. simultaneous use of condom and a diaphragm or cervical cap with 
spermicide for the female partner. 
7. Male participants (including men who have had a vasectomy) with a 
pregnant partner must agree to use a condom from the first dose and for 
90 days after the last dose. 
8. Male participants must be willing not to donate sperm for 90 days after 
the last dose. 
9. Able to understand the study procedures and provide signed informed 
consent to participate in the study. 
Exclusion Criteria: 
1. Any clinically significant abnormal finding at physical examination at 
screening. 

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2. Clinically significant abnormal laboratory test results or positive 
serology test results for hepatitis B surface antigen (HBsAg), hepatitis 
C virus (HCV) antibody, or human immunodeficiency virus (HIV) 
antigen and antibody, at screening. 
3. Any of the following laboratory parameters above the upper limit of 
normal (ULN) values at screening or baseline (Day -1): aspartate 
aminotransferase (AST), alanine aminotransferase (ALT), direct 
bilirubin, indirect bilirubin, and total bilirubin. Only abnormal values up 
to 1.5x ULN may be repeated once for confirmation to below ULN. 
4. Positive pregnancy test or lactating female participant. 
5. Positive urine drug screen, urine cotinine test, or alcohol breath test. 
6. Positive test for coronavirus 2019 (COVID-19) at admission. 
7. Known allergic reactions or hypersensitivity to camlipixant, rifampin or 
any other rifamycins (participants in Part 1 only), rabeprazole or 
substituted benzimidazoles (participants in Part 2 only), or other related 
drugs, or to any excipient in the formulation. 
8. Clinically significant ECG abnormalities (for example, QTcF > 450 ms) 
or vital signs abnormalities (systolic blood pressure lower than 90 or 
over 140 mmHg, diastolic blood pressure lower than 50 or over 
90 mmHg, or heart rate less than 50 or over 100 bpm) at screening. 
9. History of drug abuse within 1 year prior to screening or recreational 
use of soft drugs (such as medicinal or recreational marijuana) within 
1 month or hard drugs (such as cocaine, phencyclidine [PCP], crack, 
opioid derivatives including heroin, and amphetamine derivatives) 
within 3 months prior to screening. 
10. History of alcohol abuse within 1 year prior to screening or regular use 
of alcohol within 6 months prior to screening that exceeds 10 units for 
women or 15 units for men of alcohol per week (1 unit = 340 mL of 
beer 5%, 140 mL of wine 12%, or 45 mL of distilled alcohol 40%). 
11. History of gastrointestinal disorders, such as stomach ulcers, irritable 
bowel syndrome (IBS), ulcerative or pseudomembranous colitis, 
intestinal obstruction, previous liver disease, hyperbilirubinemia, 
jaundice, or elevated liver enzymes. 
12. Known Gilbert, Rotor, Crigler-Najjar, or Dubin-Johnson syndrome. 
13. Medical history of ageusia/hypogeusia/dysgeusia or known presence of 
a dysfunction in his/her ability to taste. 
14. History of clostridium difficile infection and clostridium 
difficile-associated diseases. 
15. Participants in Part 1 only: History of liver cirrhosis, liver tuberculosis, 
adenocarcinoma of the liver or neoplasm of the biliary tract. 
16. Participants in Part 1 only: History of coagulation disorders. 
17. Participants in Part 2 only: History of osteoporosis. 

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18. Participants in Part 2 only: History of subacute cutaneous lupus 
erythematosus. 
19. Use of medications for the timeframes specified below, with the 
exception of medications exempted by the Investigator on a case-by-
case basis because they are judged unlikely to affect the PK profile of 
the study drug or participant safety (e.g., topical drug products without 
significant systemic absorption): 
a. depot injection or implant within 3 months prior to dosing; 
b. any drug known to induce or inhibit hepatic drug metabolism, 
including St. John’s wort, within 30 days prior to dosing; 
c. prescription medications within 14 days prior to dosing; 
d. any vaccine, including COVID-19 vaccine, within 14 days prior to 
dosing; 
e. over-the-counter (OTC) medications and natural health products 
(including herbal remedies, homeopathic and traditional medicines, 
probiotics, food supplements such as vitamins, minerals, amino 
acids, essential fatty acids, and protein supplements used in sports) 
within 7 days prior to dosing, with the exception of the occasional 
use of acetaminophen (up to 2 g daily). 
20. Participation in a clinical research study involving the administration of 
an investigational or marketed drug or device within 30 days prior to 
dosing, administration of a biological product in the context of a clinical 
research study within 90 days prior to dosing, or concomitant 
participation in an investigational study involving no drug or device 
administration. 
21. Donation of plasma within 7 days prior to dosing or donation or loss of 
500 mL or more of whole blood within 8 weeks prior to dosing. 
22. Any reason which, in the opinion of the Investigator, would prevent the 
participant from participating in the study. 
Study Treatments: 
Participants will receive: 
• 
Camlipixant (BLU-5937) 1 x 50 mg tablet administered under 
fasting conditions 
 on Day 1 (Part 1 and Part 2) and 
Day 11 (Part 1) or Day 10 (Part 2). 
• 
Rifampin 
 mg capsules (total dose 
 mg) administered 
, for 9 consecutive days from Day 4 to Day 12 
in Part 1 only. 
• 
Rabeprazole 
 mg enteric-coated tablet administered 
 
, for 8 consecutive days from Day 4 to Day 11 in Part 2 
only. 
• 
On Day 11 (Part 1) or Day 10 (Part 2), camlipixant will be 
administered 1 hour (± 2 minutes) 
administration of 
rifampin (Part 1) or rabeprazole (Part 2). 
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On Day 1: No food will be allowed from at least 10 hours before 
camlipixant dosing until at least 4 hours after dosing. 
On Day 11 (Part 1) or Day 10 (Part 2): No food will be allowed from at 
least 10 hours before rifampin (Part 1) or rabeprazole (Part 2) dosing until at 
least 4 hours after camlipixant dosing. 
On Days 4 to 10 and Day 12 in Part 1: No food will be allowed from at least 
2 hours before rifampin dosing until 1 hour post-dose. A normo-caloric 
breakfast will be served at least 1 hour after rifampin administration. 
On Days 4 to 9 and Day 11 in Part 2: No food will be allowed from at least 
2 hours before rabeprazole dosing until 1 hour post-dose. A normo-caloric 
breakfast will be served at least 1 hour after rabeprazole administration. 
Study Procedures: 
Blood samples for PK analysis will be collected and safety procedures will 
be performed at pre-defined times throughout the study as specified in 
Table 1. Schedule of Assessments for Part 1 and Table 2. 
Schedule of 
Assessments for Part 2. 
Participants will be monitored throughout the study by the clinical staff for 
AEs and concomitant medication use. 
Statistical Analyses: 
PK analysis: 
Concentrations for rifampin (Part 1) and rabeprazole (Part 2) will be 
tabulated. They will be presented as supportive data. Descriptive statistics 
on pre-dose concentrations of rifampin in Part 1 (Days 9, 10, and 11) and 
rabeprazole in Part 2 (Days 8, 9, and 10) will be performed to evaluate the 
attainment of steady-state. 
 
 
 
 
 
Other possible exploratory markers may be considered as deemed 
necessary. 
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Metabolites of camlipixant may be assayed at a later time, if deemed 
necessary. 
Safety and tolerability analysis: 
Safety and tolerability of camlipixant alone and in combination with 
rifampin (Part 1) or rabeprazole (Part 2) will be evaluated through the 
assessment of AEs, SAEs, AEMIs (i.e., seriousness, severity, relationship to 
the study drug and the interacting drug, outcome, duration, and 
management), vital signs, 12-lead ECGs, clinical laboratory tests, and 
physical examinations. Treatment-emergent adverse events (TEAEs) will be 
tabulated by treatment. Safety and tolerability data will be reported using 
descriptive statistics. 
A Summary Table of study procedures is presented in Appendix 1. 

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Table 1. 
Schedule of Assessments for Part 1 
Study Stage 
Screening 
Baseline 
Treatment 
Follow-up 
phone call 
Day 
-28 to -1 
-1 
1 
2 
3 
4 
5-7 
8-10 
11 
12 
13 
20 ± 2 
Informed consent 
X 
 
 
 
 
 
 
 
 
 
 
 
Inclusion/exclusion criteria 
X 
 
 
 
 
 
 
 
 
 
 
 
Demographic data 
X 
 
 
 
 
 
 
 
 
 
 
 
Medical and medication history 
X 
 
 
 
 
 
 
 
 
 
 
 
Confinement 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Discharge/ET 
 
 
 
 
 
 
 
 
 
 
X14 
 
Follow-up phone call 
 
 
 
 
 
 
 
 
 
 
 
X15 
Study drug administration 
 
 
 
 
 
 
 
 
 
Camlipixant1 
 
 
X 
 
 
 
 
 
X 
 
 
 
Rifampin2 
 
 
 
 
 
X 
X 
X 
X 
X 
 
 
Pharmacokinetics 
 
 
 
 
 
 
 
 
 
 
 
 
Blood samples for PK analysis of 
Camlipixant3 
 
 
X 
X 
X 
 
 
 
X 
X 
X 
 
Blood samples for PK analysis of rifampin4 
 
 
 
 
 
X 
 
X 
X 
 
 
 
Blood sample for pharmacogenomic 
analysis 
 
X 
 
 
 
 
 
 
 
 
 
 
Safety 
 
 
 
 
 
 
 
 
 
 
 
 
Physical examination5 
X 
X 
 
 
 
 
 
X 
 
 
X 
 
Body measurements (height, weight, BMI) 
X 
 
 
 
 
 
 
 
 
 
 
 
Vital signs6 
X 
 
X 
 
 
 
 
 
X 
 
X 
 
12-lead ECG7 
X 
 
X 
 
 
X 
 
 
X 
 
X 
 
Serology tests8 
X 
 
 
 
 
 
 
 
 
 
 
 
Clinical laboratory tests (biochemistry, 
hematology, and coagulation)9 
X 
X 
 
 
 
X 
X 
X 
X 
 
X 
 
Urinalysis10 
X 
X 
 
 
 
X 
 
 
X 
 
X 
 
FSH (for post-menopausal females)11 
X 
 
 
 
 
 
 
 
 
 
 
 
Pregnancy tests12 
X 
X 
 
 
 
 
 
 
 
 
X 
 
Drug, cotinine, and alcohol screens 
X 
X 
 
 
 
 
 
 
 
 
 
 

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Study Stage 
Screening 
Baseline 
Treatment 
Follow-up 
phone call 
Day 
-28 to -1 
-1 
1 
2 
3 
4 
5-7 
8-10 
11 
12 
13 
20 ± 2 
COVID-19 test 
 
X 
 
 
X 
 
 
 
 
 
 
 
Monitoring and recording of AEs, SAEs, 
AEMIs, and prior/concomitant medication 
use13 
 
 
 
 
 
 
 
 
 
 
 
 
Abbreviations: AE = adverse event; AEMI =adverse event of medical interest; BMI = body mass index; CK = creatine kinase; COVID-19 = coronavirus 2019; 
ECG = electrocardiogram; ET = early termination; FSH = follicle-stimulating hormone; LFT = liver function test; PK = pharmacokinetic; SAE = serious adverse 
event. 
1 
On Day 11, camlipixant will be administered 1 hour (± 2 minutes) 
 administration of rifampin. 
2 
Administration of rifampin will occur at approximately 
 from Days 4 to 12. A time window of ± 10 minutes from the scheduled 
dosing time will be allowed, as long as the 1-hour (± 2 minutes) time interval between rifampin and camlipixant dosing on Day 11 is respected. 
3 
A total of 20 blood samples will be collected for PK analysis of camlipixant on Day 1 and Day 11: at pre-dose and 0.16, 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 4, 6, 
8, 10, 12, 15, 18, 24, 36, and 48 hours post-dose. Refer to Table 3 for more details. 
4 
A total of 5 blood samples will be collected for PK analysis of rifampin pre-dose on Days 4, 8, 9, 10, and 11. Refer to Table 3 for more details. 
5 
A complete physical examination will be performed at screening. A brief physical examination will be performed on Day -1, in the evening of Day 10, and at 
discharge on Day 13 (or ET). 
6 
Blood pressure, heart rate, respiratory rate, and oral temperature will be measured at screening and discharge on Day 13 (or ET). Blood pressure and heart 
rate will be measured before camlipixant dosing on Day 1 and before rifampin dosing on Day 11. 
7 
12-lead ECG will be measured at screening, before camlipixant dosing on Day 1, before rifampin dosing on Day 4 and Day 11, and at discharge on Day 13 
(or ET). 
8 
Serology tests include hepatitis B surface antigen (HbsAg), hepatitis C virus (HCV) antibody, and human immunodeficiency virus (HIV) antigen and 
antibody. 
9 
Standard biochemistry (including LFT and CK), hematology, and coagulation tests will be performed at screening, on Day -1, before rifampin dosing on 
Day 4 and Day 11, and at discharge on Day 13 (or ET). Biochemistry (including LFT and CK) will be also measured before rifampin dosing on Day 6 and 
Day 9. 
10 Urinalysis tests will be performed at screening, on Day -1, before rifampin dosing on Day 4 and Day 11, and at discharge on Day 13 (or ET). 
11 FSH levels will be measured at screening to confirm the post-menopausal status. 
12 A urine pregnancy test will be performed at screening and at discharge on Day 13 (or ET), and a serum pregnancy test will be performed on Day -1. If there 
is a positive pregnancy result following the first study drug administration, a Pregnancy Notification form is to be completed and submitted to the Sponsor. 
13 All AEs, SAEs, and AEMIs will be closely monitored and reported as indicated in safety section 8.4. Following dosing on Day 1 until discharge,  
. Also, 
in the event of 
, a COVID-19 test will be performed. 
14 In case of ET, discharge procedures will be performed as soon as possible. 
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15 A safety follow-up phone call will be performed 7 ± 2 days after discharge. 

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Table 2. 
Schedule of Assessments for Part 2 
Study Stage 
Screening 
Baseline 
Treatment 
Follow-up 
phone call 
Day 
-28 to -1 
-1 
1 
2 
3 
4 
5-6 
7-9 
10 
11 
12 
19 ± 2 
Informed consent 
X 
 
 
 
 
 
 
 
 
 
 
 
Inclusion/exclusion criteria 
X 
 
 
 
 
 
 
 
 
 
 
 
Demographic data 
X 
 
 
 
 
 
 
 
 
 
 
 
Medical and medication history 
X 
 
 
 
 
 
 
 
 
 
 
 
Confinement 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Discharge/ET 
 
 
 
 
 
 
 
 
 
 
X14 
 
Follow-up phone call 
 
 
 
 
 
 
 
 
 
 
 
X15 
Study drug administration 
 
 
 
 
 
 
 
 
 
 
 
 
Camlipixant1 
 
 
X 
 
 
 
 
 
X 
 
 
 
Rabeprazole2 
 
 
 
 
 
X 
X 
X 
X 
X 
 
 
Pharmacokinetics 
 
 
 
 
 
 
 
 
 
 
 
 
Blood samples for PK analysis of 
camlipixant3 
 
 
X 
X 
X 
 
 
 
X 
X 
X 
 
Blood samples for PK analysis of 
rabeprazole4 
 
 
 
 
 
X 
 
X 
X 
 
 
 
Blood sample for pharmacogenomic 
analysis 
 
X 
 
 
 
 
 
 
 
 
 
 
Safety 
 
 
 
 
 
 
 
 
 
 
 
 
Physical examination5 
X 
X 
 
 
 
 
X 
 
 
X 
 
Body measurements (height, weight, BMI) 
X 
 
 
 
 
 
 
 
 
 
 
 
Vital signs6 
X 
 
X 
 
 
 
 
 
X 
 
X 
 
12-lead ECG7 
X 
 
X 
 
 
X 
 
 
X 
 
X 
 
Serology tests8 
X 
 
 
 
 
 
 
 
 
 
 
 
Clinical laboratory tests (biochemistry, 
hematology, and coagulation)9 
X 
X 
 
 
 
X 
 
 
X 
 
X 
 
Urinalysis10 
X 
X 
 
 
 
X 
 
 
X 
 
X 
 
FSH (for post-menopausal females)11 
X 
 
 
 
 
 
 
 
 
 
 
 
Pregnancy tests12 
X 
X 
 
 
 
 
 
 
 
 
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Study Stage 
Screening 
Baseline 
Treatment 
Follow-up 
phone call 
Day 
-28 to -1 
-1 
1 
2 
3 
4 
5-6 
7-9 
10 
11 
12 
19 ± 2 
Drug, cotinine, and alcohol screens 
X 
X 
 
 
 
 
 
 
 
 
 
 
COVID-19 test 
 
X 
 
 
X 
 
 
 
 
 
 
 
Monitoring and recording of AEs, SAEs, 
AEMIs, and prior/concomitant medication 
use13 
 
 
 
 
 
 
 
 
 
 
 
 
Abbreviations: AE = adverse event; AEMI =adverse event of medical interest; BMI = body mass index; COVID-19 = coronavirus 2019; ECG = 
electrocardiogram; ET = early termination; FSH = follicle-stimulating hormone; LFT = liver function test; PK = pharmacokinetic; SAE = serious adverse event. 
1 
On Day 10, camlipixant will be administered 1 hour (± 2 minutes)
 administration of rabeprazole. 
2 
Administration of rabeprazole will occur at approximately 
 from Days 4 to 11. A time window of ± 10 minutes from the 
scheduled dosing time will be allowed, as long as the 1-hour (± 2 minutes) time interval between rabeprazole and camlipixant dosing on Day 10 is respected. 
3 
A total of 20 blood samples will be collected for PK analysis of camlipixant on Day 1 and Day 10: at pre-dose and 0.16, 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 4, 6, 
8, 10, 12, 15, 18, 24, 36, and 48 hours post-dose. Refer to Table 4 for more details. 
4 
A total of 5 blood samples will be collected for PK analysis of rabeprazole pre-dose on Days 4, 7, 8, 9, and 10. Refer to Table 4 for more details. 
5 
A complete physical examination will be performed at screening. A brief physical examination will be performed on Day -1, in the evening of Day 9, and at 
discharge on Day 12 (or ET). 
6 
Blood pressure, heart rate, respiratory rate, and oral temperature will be measured at screening and discharge on Day 12 (or ET). Blood pressure and heart 
rate will be measured before camlipixant dosing on Day 1 and before rabeprazole dosing on Day 10. 
7 
12-lead ECG will be measured at screening, before camlipixant dosing on Day 1, before rabeprazole dosing on Day 4 and Day 10, and at discharge on 
Day 12 (or ET). 
8 
Serology tests include hepatitis B surface antigen (HbsAg), hepatitis C virus (HCV) antibody, and human immunodeficiency virus (HIV) antigen and 
antibody. 
9 
Standard biochemistry (including LFT and CK), hematology, and coagulation tests will be performed at screening, on Day -1, before rabeprazole dosing on 
Day 4 and Day 10, and at discharge on Day 12 (or ET). 
10 Urinalysis will be performed at screening, on Day -1, before rabeprazole dosing on Day 4 and Day 10, and at discharge on Day 12 (or ET). 
11 FSH levels will be measured at screening to confirm the post-menopausal status. 
12 A urine pregnancy test will be performed at screening and at discharge on Day 12 (or ET), and a serum pregnancy test will be performed on Day -1. If there 
is a positive pregnancy result following the first study drug administration, a Pregnancy Notification form is to be completed and submitted to the Sponsor. 
13 All AEs, SAEs, and AEMIs will be closely monitored and reported as indicated in safety section 8.4. Following dosing on Day 1 until the end of the study,  
 Also, 
in the event of a 
, a COVID-19 test will be performed. 
14 In case of ET, discharge procedures will be performed as soon as possible. 
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15 A safety follow-up phone call will be performed 7 ± 2 days after discharge. 

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1. 
Introduction 
1.1 
Background Information 
Camlipixant (previously identified as BLU-5937) is a small molecule of the 
 
 that is developed for the treatment of refractory (or unexplained) chronic cough 
(RCC). It has been shown to be a potent, selective, and non-competitive P2X3 homotrimeric 
receptor antagonist. P2X3 receptors are adenosine triphosphate (ATP) cation-gated channels 
located on primary afferent neurons in various tissues, including respiratory tract. ATP released 
from damaged or inflamed tissues acts on P2X3 receptors, triggering pain or irritation signals 
transmitted by sensory afferent fibers to the brain. Specifically, the P2X3 receptor appears to 
play a role in cough hypersensitivity and has been identified as an important target in refractory 
RCC. Camlipixant was shown to reduce significantly cough frequency in patients with baseline 
awake cough frequency 
 coughs/hour in a Phase 2b clinical study.1 
 
2,3 Of note, the high selectivity of camlipixant for the P2X3 homotrimeric receptor versus 
P2X2/3 heterotrimeric receptor should reduce the taste disturbance AEs that have been 
associated to P2X2/3 and observed with other less selective P2X3 antagonists.1 
1.2 
Nonclinical 
The toxicology of camlipixant has been studied in several preclinical species. Selected findings 
are presented below. Please refer to the Investigator’s Brochure (IB) for a complete description 
and summary. Regarding the male reproductive system, camlipixant was shown to have effects 
in the testis with decreased sperm in the epididymis upon long-term administration in animal 
toxicity studies (26 weeks in rat and 39 weeks in dog). These findings were fully reversible and 
were not observed with shorter-term dosing (28 days toxicity study, and a fertility study where 
male rats were administered camlipixant up to 60 days).1 However, it is not known whether the 
effects seen in animals will also occur in men dosed with camlipixant. Since only the long-term 
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preclinical studies have resulted in testicular toxicity and that this has been observed to be 
reversible, it is considered that the risks to healthy male adults receiving single doses, and with a 
suitable washout period between doses, is minimal.  
Lens and corneal opacities have been observed upon chronic 26- and 39-week administration in 
rats and dogs, respectively. These were minor in terms of severity and were considered 
non-adverse as they are not expected to affect the vision. These were not observed with 
short-term dosing and the risks to healthy participants receiving single doses is considered 
minimal.1 
1.3 
Clinical 
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To date, approximately 560 participants have been exposed to camlipixant at doses ranging from 
12.5 mg to 1200 mg as single or multiple BID doses for up to 4 weeks in Phase 1 and Phase 2 
studies. Camlipixant was found to be generally well tolerated in healthy adult participants, 
participants with RCC, and participants with chronic pruritis associated with atopic dermatitis. 
Overall, 210 healthy participants have been exposed to camlipixant at doses ranging from 
12.5 mg to 1200 mg as single or multiple doses in Phase 1 studies. There were no deaths or 
serious adverse events (SAEs) reported during these studies. The most common TEAEs 
(camlipixant/placebo) following administration were headache (10.0% / 3.2%), somnolence 
(9.5% [possibly all related to
 in a DDI study]) / 0.0%), dysgeusia (9.0% / 1.6%), 
constipation (6.2% / 0.0%), dizziness (5.2% / 0.0%), nausea (4.3% / 4.8%), hypoesthesia (3.8% / 
0.0%), diarrhea (3.3% / 0.0%), dyspepsia (2.4% / 1.6%), and abdominal pain (0.0% / 3.2%). 
There were no significant changes in vital signs or ECG parameters at any dose level. There 
were no significant changes in laboratory parameters, except for two isolated cases of mild 
elevations in liver enzymes (alanine aminotransferase [ALT] and/or aspartate aminotransferase 
[AST]), 1 case at 400 mg BID in the FIH and one case at 200 mg BID in a DDI study (BUS-P1-
02). In both cases, these elevations in liver enzymes were not associated with a concomitant 
increase in bilirubin or with clinical symptoms of liver injury. There was a slight trend of 
increased bilirubin in the FIH study (especially at 400 mg BID) and 1 case with 200 mg BID in a 
DDI study (BUS-P1-02; both representing a supra-therapeutic dose), which were not associated 
with any concomitant increases in liver enzymes. The mild elevation in bilirubin in the absence 
of increased liver enzyme levels is likely due to the drug’s interference in bilirubin disposition 
through OATP inhibition and is likely to represent a benign process. Overall, 3 participants were 
discontinued from the Phase 1 clinical studies due to TEAEs, all from the DDI (BUS-P1-02) 
study at the 200 mg BID dose: 2 participants had mild rash (camlipixant) and one of these 
participants had increased AST and ALT levels (sulfasalazine alone).1 
 
 
. 
Refer to the IB v.5 and the IB addendum for detailed background information on camlipixant.1 
1.4 
Background Information on Rifampin 
Rifampin is indicated for the treatment of pulmonary tuberculosis, as well as prophylaxis for 
meningococcal infection. The recommended dosage should not exceed a once daily dose of 
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600 mg for the treatment of tuberculosis and 600 mg twice daily for treatment of meningococcal 
infection. It is recommended that rifampin be administered once daily on an empty stomach 
(1 hour before a meal) to ensure optimum absorption. AEs associated with rifampin are listed in 
the Product Monograph.5  
Rifampin may be bacteriostatic or bactericidal in action, depending on the concentration of the 
drug attained at the site of infection and the susceptibility of the infecting organism. Rifampin 
suppresses initiation of chain formation for ribonucleic acid (RNA) synthesis in susceptible 
bacteria by inhibiting deoxyribonucleic acid (DNA)-depending RNA polymerase.5 
Rifampin is well absorbed from the gastrointestinal tract. Time to peak plasma concentration is 
1.5 to 4 hours after oral administration; peak concentration may be decreased and delayed 
following administration with food. Its elimination half-life is initially 3 to 5 hours; with 
repeated administration half-life decreasing to 2 to 3 hours.5  
Both in the laboratory animal and man, the administration of rifampin has been associated with 
evidence of induction of drug metabolizing enzyme systems of the liver,5 especially the CYP 
family including 
  
1.5 
Background Information on Rabeprazole 
Rabeprazole is a substituted benzimidazole PPI. It is indicated for the treatment of conditions 
where a reduction of gastric acid secretion is required, such as erosive or ulcerative 
gastroesophageal reflux disease (GERD), symptomatic GERD (also known as non-erosive reflux 
disease [NERD]), duodenal and gastric ulcers, and hypersecretory conditions such as 
Zollinger-Ellison syndrome. In combination with antibiotics, it is also used to eradicate 
Helicobacter pylori associated with duodenal ulcer disease. The recommended daily dosage 
ranges from 10 to 60 mg, depending on the disease being treated, with 10 to 20 mg once daily 
being the most frequently recommended dosing regimen. Doses up to 100 mg 
and 60 mg 
twice daily (BID) have been administered as well. AEs associated with rabeprazole are listed in 
the Product Monograph.7  
Rabeprazole sodium is an antisecretory compound that suppresses gastric acid secretion by 
inhibiting the gastric H+, K+- ATPase at the secretory surface of the gastric parietal cell. 
Because this enzyme is regarded as the acid (proton) pump within the parietal cell, rabeprazole 
has been characterized as a gastric PPI.7 
Following oral administration, rabeprazole is rapidly absorbed and can be detected in plasma as 
early as 0.5 hours. After oral administration of 
mg rabeprazole, peak plasma concentrations 
(Cmax) are reached at an average of 1.6 to 5.0 hours. Bioavailability is 52%. The rabeprazole Cmax 
and AUC are linear with doses from 10 mg to 40 mg. Rabeprazole does not accumulate and its 
PK are not altered by multiple dosing. Rabeprazole is 96.3% bound to human plasma proteins.7 
Taking rabeprazole tablets with food does not alter Cmax or AUC relative to the fasting state; the 
Tmax is increased by 1.7 hours. Administration of rabeprazole with a high fat meal may delay its 
absorption by approximately 4 hours or longer; however, the Cmax and AUC are not altered.7  
The plasma half-life is approximately 1 hour.7  
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1.6 
Study Rationale 
Part 1: 
In vitro studies indicate that 
 play a role in the 
oxidative metabolism of camlipixant.
 
 
1 
Metabolic induction may result in decreased plasma concentrations of drugs and/or their active 
metabolite(s). These decreased plasma concentrations may diminish the therapeutic effects of 
these drugs. 
Therefore, the purpose of Part 1 is to assess, in vivo, the potential of camlipixant to be a victim of 
DDIs precipitated by inducers CYP enzymes (
 believed to be important 
in the biotransformation of camlipixant. In accordance with the recommendations provided in the 
FDA Guidance for Clinical Drug Interaction Studies – Cytochrome P450 Enzyme- and 
Transporter-Mediated Drug Interactions (2020),8 multiple doses of the CYP inducer, rifampin,9 
will be administered to evaluate the effect on the PK of single dose camlipixant. Rifampin was 
judged to be the optimal choice among CYP inducers for this study, given its ability to induce 
both 
 It is a clinically validated, strong inducer for 
 and one of 
the only clinically validated inducers of CYP2C8.9 Additionally, rifampin does not require an 
initial up-titration phase, allowing for an overall shorter exposure time to the perpetrator drug 
and reduces study duration for healthy participants. Therefore, in terms of participant safety, the 
selection of this clinical index inducer represents an advantageous risk mitigation strategy, 
because, with appropriate dosing duration, it allows to achieve sufficient CYP3A induction while 
limiting exposure. Moreover, the use of rifampin to induce both 
 and 
 
represents the worst-case scenario and will enable the Sponsor to validate and refine an existing 
PBPK model and delineate the relative contributions of the two metabolic pathways in clearance 
of camlipixant. Therefore, rifampin is the most optimal inducer to achieve these objectives and 
characterize the DDI profile of camlipixant. 
Part 2: 
Solubility of camlipixant in simulated biological fluids and in buffers at different pH was 
assessed at 37°C.
 
1 Based on the FDA Guidance for Evaluation of Gastric 
pH-Dependent Drug Interactions With Acid-Reducing agents: Study Design, Data Analysis, and 
Clinical Implications (2020), most drugs that have demonstrated pH-dependent DDIs are weak 
bases with low intrinsic aqueous solubility compared to the solubility needed to dissolve the 
clinical dose (i.e., dose divided by 250 mL water).10 In other words, the potential for an 
interaction with pH modifying agents is low when the solubility of a drug is higher than the dose 
divided by 250 mL. 
 
 
 
 
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Accordingly, the purpose of Part 2 is to assess, in vivo, the potential of camlipixant to be a victim 
of DDIs related to reduction in gastric pH. Among acid-reducing agents, PPIs are listed in the 
FDA Guidance for Evaluation of Gastric pH-Dependent Drug Interactions With Acid-Reducing 
agents: Study Design, Data Analysis, and Clinical Implications (2020) as producing long lasting 
effects on gastric pH. In this study, multiple doses of the PPI rabeprazole, mentioned in the 
FDA’s guidance,9 will be administered to evaluate the effect on the PK of single-dose 
camlipixant. Considering that a range of cytochromes (CYPs) are involved in the metabolism of 
camlipixant, rabeprazole is an appropriate choice of PPI as it has a low affinity for a range of 
CYP isoenzymes.11  
1.6.1 
Analytes to Measure 
The analytes to be measured will include the investigational drug camlipixant (Parts 1 and 2), as 
well as rifampin (Part 1) and rabeprazole (Part 2). 
Metabolites of camlipixant may be assayed at a later time, if deemed necessary. 
In this clinical study, rifampin (Part 1) and rabeprazole (Part 2) will be administered in a 
controlled setting i.e., within a clinical research unit with directly observed dosing. Thus, it is not 
relevant to measure extensively rifampin or rabeprazole blood levels. Accordingly, as 
participants will be confined to the clinical unit the full duration of the study, only sparse 
samples for rifampin (Part 1) and rabeprazole (Part 2) will be collected to provide information on 
attainment of steady-state, or to help explain any aberrant results. 
1.6.2 
Rationale for the Dose and Dosing Regimen 
 
 
 
 
 
  
According to the FDA guidance,8 the dose of the perpetrator drug used in DDI studies should 
maximize the possibility of identifying a DDI, by using the maximum approved dose and 
shortest dosing interval. For inducers, such as rifampin, multiple doses are used to ensure the 
maximal induction of a specific pathway. Except for prophylaxis of meningococcal infection, the 
maximal dose and dosing regimen of rifampin in the clinical setting is 
 mg 
.5 According 
to the literature, 
mg was the most commonly used dose in DDI studies using rifampin as a 
perpetrator drug. The duration of rifampin dosing varies between studies. Dosing for 7 days is 
expected to achieve near maximal induction.12 In the interest of not exposing healthy participants 
to more than the minimum required lead-in period of rifampin, and, considering that 7 days of 
dosing is common practice in the literature, co-administration of rifampin with the 
investigational drug will occur on the 8th day of rifampin dosing in this study. This approach has 
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been judged to be sufficient to achieve adequate 
 induction, while minimizing 
unnecessary exposure and safety risks. Following co-administration with camlipixant, rifampin 
will continue to be administered for 1 day, in order to maintain 
 induction during the 
collection period for PK sampling of camlipixant. Therefore, a 
 mg dose of rifampin given 
 as oral capsules for 9 consecutive days, with administration of rifampin 1 hour before 
camlipixant dosing on the 8th day of rifampin administration, has been selected for Part 1. 
Based on the FDA DDI guidance on acid-reducing agents, pre-treatment with PPIs for several 
days (e.g., 4 to 5 days) is needed to reach the pharmacodynamic steady-state of PPIs before 
administering the investigational drug. It is preferable to select a dose that is expected to provide 
a near maximum effect on pH elevation.10 In this study, attainment of maximal effect on pH will 
be ensured by a lead-in period of 6 days with rabeprazole before co-administration of 
camlipixant on the 7th day of rabeprazole dosing. A dose of 
 of rabeprazole represents the 
highest recommended dose for most indications,7 and is in line with the dose listed in the FDA 
guidance.10 The effect of PPIs on gastric pH is long lasting, and thus staggered administration of 
an investigational drug with a PPI is not expected to mitigate the DDI risk.10 A 1-hour time 
interval between rabeprazole and camlipixant dosing will be kept for the day of 
co-administration as standardization with other previously performed DDI studies with 
camlipixant, without minimizing the possible effect on pH. Following co-administration with 
camlipixant, rabeprazole will continue to be administered for 1 day, as a conservative approach. 
Therefore, a 
mg dose of rabeprazole given 
as an oral tablet for 8 consecutive days, with 
administration of rabeprazole 1 hour before camlipixant dosing on the 7th day of rabeprazole 
administration, has been selected for Part 2. 
1.6.3 
Pharmacogenomic Testing 
One blood sample for pharmacogenomic testing will be taken on Day -1.
 
 The sample may be also used to investigate other possible exploratory markers as 
deemed necessary. 
1.6.4 
Rationale for the Study Population 
A healthy volunteer population has been selected for the study because healthy participants with 
no concomitant diseases and using no concomitant medications represent a homogenous 
population allowing for proper evaluation of the PK, safety, and tolerability of a drug without 
confounding factors. 
Embryo-fetal development (EFD) and female and male fertility studies on camlipixant in rats 
and rabbits did not identify any findings of concern for humans, including teratogenicity, at the 
proposed clinical doses (safety margins >20 at the 50 mg single dose proposed in this current 
study). The no observed adverse effect levels (NOAEL) for EFD toxicity in pregnant rats was 
100 mg/kg/day with lower maternal body weights, lower fetal body weights, and increased 
incidence of fetal tail abnormalities and skeletal variations observed at the highest dose tested 
(250 mg/kg/day). No test article-related effects on maternal survival, clinical findings, ovarian 
and uterine parameters or gross macroscopic findings were observed at any camlipixant dose 
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level evaluated. The NOAEL for fertility and reproductive effects and early embryonic 
development in female rats was 150 mg/kg/day due to adverse lower fertility and fecundity 
indices, lower number of implantation sites, and post implantation loss observed at 
450 mg/kg/day. In the EFD study in pregnant rabbits, based upon the maternal clinical signs and 
lower body weight gain and food consumption at 450 mg/kg/day, the NOAEL for maternal 
toxicity was considered to be 200 mg/kg/day while the NOAEL for EFD toxicity is considered to 
be 450 mg/kg/day. In the male fertility study, the no observed effect level (NOEL) for paternal 
toxicity and male mating, fertility, sperm parameters, and reproductive outcome is considered to 
be 450 mg/kg/day.1 There have been no clinical studies of camlipixant conducted in pregnant 
women. 
Rifampin has been demonstrated to cross the placental barrier and is teratogenic in rodents when 
given orally. In rat studies, a greater number of reabsorbed fetuses and a dose-related decrease in 
fetal weights were observed in the group receiving 200 mg/kg. Treatment with 200 mg/kg of 
rifampin caused an incidence of fusion of the palatine bones, two cases of general malformations 
(monstrosity), one case of bone malformation which consisted of bone centers of the sternum 
divided or missing entirely and fusion of vertebral bodies. In rabbits treated with 200 mg/kg 
rifampin, the number of reabsorbed fetuses were higher and the number of live fetuses lower. 
This was a dose-related effect. The progeny of rabbits treated with 200 mg/kg rifampin showed 
evidence of fissure of the second bone of the sternum, along with hydrocephalus. Also in this 
group, an incidence of 11.9% of spina bifida was observed. In mice, doses of 150-200 mg/kg 
caused dose-dependent toxic effects on the embryos and malformations (particularly cleft palate 
and spina bifida) in 5-10% of the pregnant mice. It is recommended that pregnant women with 
tuberculosis be treated for a minimum of 9 months with multi-drug therapy, including rifampin. 
It has rarely caused postnatal hemorrhages in the mother and infant when administered during 
the last few weeks of pregnancy; vitamin K may be indicated. Neonates should be carefully 
observed for evidence of adverse effects.5 While there are no well controlled studies in pregnant 
women, cases of fetal malformation have been reported when used during pregnancy.13 Thus, 
women of childbearing potential will not be recruited into Part 1; only male and 
non-childbearing potential female participants will be included into this part of the study. 
Sexually active non-surgically-sterile male participants with female partners of childbearing 
potential will be required to use a double contraceptive method. 
For rabeprazole, at maternally toxic doses (25 and 50 mg/kg) in the rat EFD study, incomplete 
ossification of the parietal and/or occipital bones was observed. There were no other effects on 
viability, weight or morphology. At maternally toxic doses (30 mg/kg) in the rabbit EFD study, 
decreased fetal weight and delayed ossification of the proximal tibial epiphysis was observed. 
There were no other effects on fetal viability or morphology. Adequate absorption of rabeprazole 
was demonstrated in the rabbit during the organogenesis period. No effects on fetal development, 
parturition, lactation, postnatal growth and offspring development, or offspring reproductive 
performance were observed in this study. The safety of rabeprazole treatment in pregnancy has 
not been established. Rabeprazole tablets should not be administered to pregnant women unless 
the expected benefits outweigh the potential risks to the fetus.7 In light of these data, only male 
and non-pregnant, non-lactating female participants will be included in Part 2. Sexually active 
female participants of childbearing potential and non-surgically-sterile male participants with 
female partners of childbearing potential will be required to use a double contraceptive method. 

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In order to avoid any potential DDIs associated with hormonal contraceptives in this study, 
hormonal methods of contraception will not be allowed for female participants. 
Pregnancy tests will also be performed at different times over the course of the study for female 
participants. Additional pregnancy reporting information is provided in section 8.4.7. 
Additionally, caution in dosage of rifampin is recommended in elderly persons.5 Furthermore, in 
20 healthy elderly participants given a 
 mg rabeprazole dose 
 for seven days, the AUC 
doubled and the Cmax increased by 60% compared to measurements in a parallel younger control 
group. Also, several published observational studies suggest that PPI therapy may be associated 
with an increased risk for osteoporosis-related fractures of the hip, wrist or spine. In the geriatric 
population, benefits of use of PPIs should be weighed against the increased risk of fractures as 
patients in this category may already be at high risk of osteoporosis-related fractures.7 Therefore, 
the population in this study will include healthy individuals between the ages of 18 and 55 years. 
1.7 
Benefit/Risk Assessment 
The inclusion and exclusion criteria have been chosen to select participants who are known to be 
free from any significant illness, history of autoimmune diseases, and from any condition that 
could impact their safety or interfere with meeting the study objectives. The proposed safety 
screening and monitoring assessments are deemed to be sufficient to monitor potential risks of 
camlipixant administration alone and in combination with rifampin or rabeprazole. There is no 
anticipated therapeutic benefit for the healthy participants in this study. 
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2. 
Objectives 
Primary objectives: 
• To assess the effect of repeated oral doses of rifampin, a 
 and 
 inducer 
(Part 1), or rabeprazole, a PPI (Part 2), on the PK of a single oral dose of camlipixant 
(BLU-5937), administered to healthy participants. 
Secondary objective: 
• To evaluate the safety and tolerability of camlipixant when administered alone and in 
combination with rifampin or rabeprazole to healthy participants. 
3. 
Endpoints 
Primary endpoints: 
• PK parameters: AUC0-inf, AUC0-t, and Cmax 
Secondary endpoints: 
• PK parameters: Tmax, T½ el, Residual area, Kel, Cl/F, and Vz/F 
• Safety evaluation: 
o AEs, SAEs, AEMIs, vital signs measurements (blood pressure, heart rate, respiratory 
rate, and oral temperature), 12-lead ECG recordings, physical examinations, and 
clinical laboratory test results, including hematology, biochemistry, coagulation, and 
urinalysis. 
4. 
Study Design 
This is a single-center, 2-part, Phase 1, open-label, fixed-sequence, DDI study designed to 
compare the PK of camlipixant when administered with and without rifampin (Part 1) or 
rabeprazole (Part 2) in healthy participants under fasting conditions. The start of study conduct 
for Part 2 is independent from Part 1 study conduct. 
A total of 32 participants will be enrolled to either Part 1 or Part 2 (16 participants in each part). 
In each part, participants will receive the assigned treatment. 
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In Part 1, participants will receive a single oral dose of 1 x 50 mg camlipixant tablet on Day 1, 
followed by 48 hours of PK and safety assessments. Repeated oral doses of 
 mg rifampin 
capsules (total dose 
mg) will be administered 
 on Days 4 to 12, with co-administration of 
a 
 mg camlipixant tablet with rifampin capsules on Day 11. 
Administration of camlipixant on Day 11 will occur 1 hour (± 2 minutes) after administration of 
rifampin, followed by 48 hours of PK and safety assessments. The study design is presented in 
Figure 1. 
Figure 1. Study Design Diagram for Part 1 
 
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In Part 2, participants will receive a single oral dose of 1 x 50 mg camlipixant tablet on Day 1, 
followed by 48 hours of PK and safety assessments. Repeated oral doses of 
 mg 
rabeprazole enteric-coated tablets will be administered 
 on Days 4 to 11, with 
co-administration of a single oral dose of 1 x 50 mg camlipixant tablet with rabeprazole 
enteric-coated tablet on Day 10. Administration of camlipixant on Day 10 will occur 1 hour 
(± 2 minutes) after administration of rabeprazole, followed by 48 hours of PK and safety 
assessments. The study design is presented in Figure 2. 
Figure 2. Study Design Diagram for Part 2 
 
The study will include a screening visit from Day -28 to Day -1. In each part of the study, 
eligible participants will be admitted to the clinical site on Day -1 and will be confined until 
completion of the assessments on Day 13 (Part 1) or Day 12 (Part 2). There will be a washout 
period of at least 3 days between the first dose of camlipixant on Day 1 and the first dose of 
rifampin (Part 1) or rabeprazole (Part 2) on Day 4. A follow-up phone call will be performed 
7 ± 2 days after discharge (Day 20 ± 2 in Part 1 and Day 19 ± 2 in Part 2). 
Outings may be permitted during confinement. If permitted, outings will be supervised at all 
times by the clinical site staff to ensure compliance with the protocol and will be limited to the 
grounds surrounding the clinic. 
The total duration of study participation for each participant from screening through the 
follow-up phone call is anticipated to be approximately 7 weeks for Part 1 and 7 weeks for 
Part 2. 
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Each study part is intended to dose in one group; if, for any reason, the study is dosed in more 
than one group, all groups will be dosed at the same clinical site and the same protocol 
requirements and procedures will be followed within each group. 
5. 
Study Population 
5.1 
Number of Participants 
It is planned to enroll up to 16 participants in Part 1 and 16 participants in Part 2 for participation 
in this study (total of 32 participants) in order to have at least 12 evaluable participants for PK 
analysis in each part of the study. No formal sample size calculation has been made. Based on 
experience from previous similar studies, a total of 32 participants (16 in each study part) was 
considered sufficient to adequately characterize the PK potential for a clinical DDI. 
5.2 
Inclusion Criteria 
Participants must meet all of the following criteria to be included in the study: 
1. Male (Parts 1 and 2) or non-childbearing potential female (Part 1) or female (Part 2), 
non-smoker (no use of tobacco or nicotine products within 3 months prior to screening), ≥18 
and ≤55 years of age, with BMI >18.5 and <30.0 kg/m2 and body weight ≥50.0 kg for males 
and ≥45.0 kg for females. 
2. Healthy as defined by: 
c. the absence of clinically significant illness and surgery within 4 weeks prior to dosing. 
d. the absence of clinically significant history of neurological, endocrine, cardiovascular, 
respiratory, hematological, immunological, psychiatric, gastrointestinal, renal, hepatic, 
and metabolic disease. 
3. Female participants of non-childbearing potential (Part 1 and Part 2) must be: 
a. post-menopausal (spontaneous amenorrhea for at least 12 months prior to dosing) with 
confirmation by documented FSH levels ≥40 mIU/mL; or 
b. surgically sterile (bilateral oophorectomy, bilateral salpingectomy, or hysterectomy) at 
least 3 months prior to dosing. 
4. Female participants of childbearing potential (Part 2 only) who are sexually active with a 
non-sterile male partner (sterile male partners are defined as men vasectomized for at least 
3 months prior to dosing) must be willing to use one of the following acceptable 
contraceptive methods throughout the study and for 30 days after the last dose: 
a. simultaneous use of non-hormonal intrauterine device placed at least 4 weeks prior to 
dosing and condom for the male partner; 
b. simultaneous use of diaphragm or cervical cap with spermicide and condom for the male 
partner, started at least 21 days prior to dosing; 
c. tubal ligation at least 3 months prior to dosing. 

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5. Female participants must be willing not to donate ova for 30 days after the last dose. 
6. Male participants who are not vasectomized for at least 3 months prior to dosing and who are 
sexually active with a female partner of childbearing potential must be willing to use one of 
the following acceptable contraceptive methods from the first dose and for 90 days after the 
last dose: 
a. simultaneous use of condom and hormonal contraceptive (e.g., oral, patch, depot 
injection, implant, vaginal ring, intrauterine device) or non-hormonal intrauterine device 
used for at least 4 weeks prior to sexual intercourse for the female partner; 
b. simultaneous use of condom and a diaphragm or cervical cap with spermicide for the 
female partner. 
7. Male participants (including men who have had a vasectomy) with a pregnant partner must 
agree to use a condom from the first dose and for 90 days after the last dose. 
8. Male participants must be willing not to donate sperm for 90 days after the last dose. 
9. Able to understand the study procedures and provide signed informed consent to participate 
in the study. 
5.3 
Exclusion Criteria 
Participants to whom any of the following applies will be excluded from the study: 
1. Any clinically significant abnormal finding at physical examination at screening. 
2. Clinically significant abnormal laboratory test results or positive serology test results for 
HBsAg, HCV antibody, or HIV antigen and antibody, at screening. 
3. Any of the following laboratory parameters above the ULN values at screening or baseline 
(Day -1): AST, ALT, direct bilirubin, indirect bilirubin, and total bilirubin. Only abnormal 
values up to 1.5x ULN may be repeated once for confirmation to below ULN. 
4. Positive pregnancy test or lactating female participant. 
5. Positive urine drug screen, urine cotinine test, or alcohol breath test. 
6. Positive test for coronavirus 2019 (COVID-19) at admission. 
7. Known allergic reactions or hypersensitivity to camlipixant, rifampin or any other rifamycins 
(participants in Part 1 only), rabeprazole or substituted benzimidazoles (participants in Part 2 
only), or other related drugs, or to any excipient in the formulation. 
8. Clinically significant ECG abnormalities (for example, QTcF > 450 ms) or vital signs 
abnormalities (systolic blood pressure lower than 90 or over 140 mmHg, diastolic blood 
pressure lower than 50 or over 90 mmHg, or heart rate less than 50 or over 100 bpm) at 
screening. 
9. History of drug abuse within 1 year prior to screening or recreational use of soft drugs (such 
as medicinal or recreational marijuana) within 1 month or hard drugs (such as cocaine, 
phencyclidine [PCP], crack, opioid derivatives including heroin, and amphetamine 
derivatives) within 3 months prior to screening. 

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10. History of alcohol abuse within 1 year prior to screening or regular use of alcohol within 
6 months prior to screening that exceeds 10 units for women or 15 units for men of alcohol 
per week (1 unit = 340 mL of beer 5%, 140 mL of wine 12%, or 45 mL of distilled alcohol 
40%). 
11. History of gastrointestinal disorders, such as stomach ulcers, IBS, ulcerative or 
pseudomembranous colitis, intestinal obstruction, previous liver disease, hyperbilirubinemia, 
jaundice, or elevated liver enzymes. 
12. Known Gilbert, Rotor, Crigler-Najjar, or Dubin-Johnson syndrome. 
13. Medical history of ageusia/hypogeusia/dysgeusia or known presence of a dysfunction in 
his/her ability to taste. 
14. History of clostridium difficile infection and clostridium difficile-associated diseases. 
15. Participants in Part 1 only: History of liver cirrhosis, liver tuberculosis, adenocarcinoma of 
the liver or neoplasm of the biliary tract. 
16. Participants in Part 1 only: History of coagulation disorders. 
17. Participants in Part 2 only: History of osteoporosis. 
18. Participants in Part 2 only: History of subacute cutaneous lupus erythematosus. 
19. Use of medications for the timeframes specified below, with the exception of medications 
exempted by the Investigator on a case-by-case basis because they are judged unlikely to 
affect the PK profile of the study drug or participant safety (e.g., topical drug products 
without significant systemic absorption): 
a. depot injection or implant within 3 months prior to dosing; 
b. any drug known to induce or inhibit hepatic drug metabolism, including St. John’s wort, 
within 30 days prior to dosing; 
c. prescription medications within 14 days prior to dosing; 
d. any vaccine, including COVID-19 vaccine, within 14 days prior to dosing; 
e. OTC medications and natural health products (including herbal remedies, homeopathic 
and traditional medicines, probiotics, food supplements such as vitamins, minerals, amino 
acids, essential fatty acids, and protein supplements used in sports) within 7 days prior to 
dosing, with the exception of the occasional use of acetaminophen (up to 2 g daily). 
20. Participation in a clinical research study involving the administration of an investigational or 
marketed drug or device within 30 days prior to dosing, administration of a biological 
product in the context of a clinical research study within 90 days prior to dosing, or 
concomitant participation in an investigational study involving no drug or device 
administration. 
21. Donation of plasma within 7 days prior to dosing or donation or loss of 500 mL or more of 
whole blood within 8 weeks prior to dosing. 
22. Any reason which, in the opinion of the Investigator, would prevent the participant from 
participating in the study. 

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5.4 
Participant Withdrawal and Replacement 
Participants will be advised that they are free to withdraw from the study at any time. Over the 
course of the study, the Sponsor and the Investigator or designee may withdraw any participant 
from the study for one of the reasons described below; participant withdrawal will be done in 
accordance with the clinical site’s SOP: 
• Safety reason; 
• Non-compliance with protocol requirements; 
• Significant protocol deviation; 
• Positive pregnancy test, drug screen, cotinine test, or alcohol breath test. 
Participants who withdraw or are withdrawn from the study after dosing will not be replaced. 
However, in the event that the number of drop-outs exceeds initial expectations, participants who 
withdraw or are withdrawn might be replaced at the discretion of the Sponsor. Such replacement 
resulting in dosing more participants than planned in this protocol would be documented in a 
protocol amendment. 
Participants who withdraw or are withdrawn will be asked to remain at the clinic until the 
Investigator or designee agrees that the participant is fine and can be discharged. As soon as 
participant withdrawal is confirmed, blood sampling will be stopped. A PK blood sample may be 
collected at the time of withdrawal if deemed required by the Investigator. Discharge/ET 
procedures will be performed at the time of withdrawal from the study or as soon as possible 
thereafter. 
6. 
Study Treatments 
6.1 
Drug Supplies and Accountability 
It is the responsibility of the Sponsor to ensure that study drug provided for this study are 
manufactured under Good Manufacturing Practice (GMP) and are suitable for human use. The 
Sponsor is responsible to ship a sufficient amount of dosage units to allow the clinical site to 
maintain an appropriate sampling for the study. 
The clinical site will be responsible for sourcing rifampin from the Canadian or US market and 
rabeprazole from the Canadian market. 
The study drugs will be stored at the clinical site pharmacy as per applicable requirements in a 
locked, environmentally-controlled medication room with restricted access. Container(s) will be 
labeled according to applicable regulations. 
Individual doses for each participant will be dispensed at the clinical site pharmacy, as per 
appropriate SOP and according to the fixed-sequence, in appropriate containers indicated with at 
least the project number and the participant number/spare number. 
All study drugs received at the site will be inventoried and accounted for throughout the study 
and the result recorded in the drug accountability record according to the clinical site appropriate 
SOP. 

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6.2 
Identification of Treatments 
Parts 1 and 2: 
 
 
Part 1: 
 mg capsules of rifampin, total dose 
 mg (Sourced from the Canadian 
or US market) administered 
, for 9 consecutive days from 
Day 4 to Day 12 in Part 1 only. 
Part 2: 
 mg of rabeprazole enteric-coated tablet (Sourced from the Canadian 
market) administered 
, for 8 consecutive days from Day 4 to 
Day 11 in Part 2 only. 
6.3 
Randomization and Blinding 
This study will be an open-label study due to the objective nature of the data. Thus, no 
randomization and blinding measures will be applied. Participants will be administered each 
treatment according to the fixed-sequence scheme. 
6.4 
Study Drug Administration 
Part 1: 
On Day 1 and Day 11, camlipixant will be administered to each participant with 240 mL of 
water. On Day 11, camlipixant will be administered 1 hour after administration of rifampin 
dosing, with a time-tolerance window of ± 2 minutes. The time of administration of both 
camlipixant and rifampin will be recorded, and the time interval between the 2 administrations 
must not fall outside of the scheduled acceptable range. 
Rifampin will be administered to each participant as capsules 
 for 
9 consecutive days, from Day 4 to Day 12. The rifampin capsules will be administered to each 
participant with 240 mL of water. In the event that participants cannot swallow all capsules with 
240 mL of water, additional water may be allowed up to a maximum total volume of 400 mL. 
Administration of rifampin will be performed at approximately the same time on Days 4 to 12. A 
time window of ± 10 minutes from the scheduled rifampin dosing time will be allowed, as long 
as the 1-hour (± 2 minutes) time interval between rifampin and camlipixant dosing on Day 11 is 
respected. 
A hand and mouth check will be performed to ensure consumption of the medication. 
On Day 1, no food will be allowed from at least 10 hours before camlipixant dosing until at least 
4 hours post-dose. 
On Day 11, no food will be allowed from at least 10 hours before rifampin dosing until at least 
4 hours after camlipixant dosing. 
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On Days 4 to 10 and Day 12: No food will be allowed from at least 2 hours before rifampin 
dosing until 1 hour post-dose. A normo-caloric breakfast will be served at least 1 hour after 
rifampin administration. 
On Day 1, except for water given with camlipixant, no fluids will be allowed for 1 hour before 
dosing until 1 hour post-dose. On Day 11, except for water given with camlipixant and rifampin 
dosing, no fluids will be allowed for 1 hour before rifampin dosing until 1 hour post-dose of 
camlipixant. On Days 4, 5, 6, 7, 8, 9, 10, and 12, except for water given with rifampin dosing, no 
fluids will be allowed for 1 hour before dosing until 1 hour post-dose. Water will be provided ad 
libitum at all other times. 
Meals will be standardized throughout the study. 
Part 2: 
On Day 1 and Day 10, camlipixant will be administered to each participant with 240 mL of 
water. On Day 10, camlipixant will be administered 1 hour after administration of rabeprazole 
dosing, with a time-tolerance window of ± 2 minutes. The time of administration of both 
camlipixant and rabeprazole will be recorded, and the time interval between the 
2 administrations must not fall outside of the scheduled acceptable range. 
Rabeprazole will be administered to each participant as tablet 
 for 
8 consecutive days, from Day 4 to Day 11. The rabeprazole tablet will be administered to each 
participant with 240 mL of water. Administration of rabeprazole will be performed at 
approximately the same time on Days 4 to 11. A time window of ± 10 minutes from the 
scheduled rabeprazole dosing time will be allowed, as long as the 1-hour (± 2 minutes) time 
interval between rabeprazole and camlipixant dosing on Day 10 is respected. 
A hand and mouth check will be performed to ensure consumption of the medication. 
On Day 1, no food will be allowed from at least 10 hours before camlipixant dosing until at least 
4 hours post-dose. 
On Day 10, no food will be allowed from at least 10 hours before rabeprazole dosing until at 
least 4 hours after camlipixant dosing. 
On Days 4 to 9 and Day 11: No food will be allowed from at least 2 hours before rabeprazole 
dosing until 1 hour post-dose. A normo-caloric breakfast will be served at least 1 hour after 
rabeprazole administration. 
On Day 1, except for water given with the camlipixant, no fluids will be allowed for 1 hour 
before dosing until 1 hour post-dose. On Day 10, except for water given with camlipixant and 
rabeprazole dosing, no fluids will be allowed for 1 hour before rabeprazole dosing until 1 hour 
post-dose of camlipixant. On Days 4, 5, 6, 7, 8, 9, and 11, except for water given with 
rabeprazole dosing, no fluids will be allowed for 1 hour before dosing until 1 hour post-dose. 
Water will be provided ad libitum at all other times. 
Meals will be standardized throughout the study. 
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7. 
Study Restrictions 
7.1 
Concomitant Medications 
Participants will be required to avoid receiving any vaccination (including COVID-19 vaccine) 
and using prescription medications, OTC medications, and natural health products (including 
herbal remedies, homeopathic and traditional medicines, probiotics, food supplements such as 
vitamins, minerals, amino acids, essential fatty acids, and protein supplements used in sports) for 
the period of time specified in exclusion criterion no. 19 and throughout the study.  
Hormonal contraception and hormone replacement therapy for female participants will not be 
allowed. 
No concomitant medications will be allowed during the study, with the exception of medications 
required for the medical management of an AE/SAE, and medications exempted by the 
Investigator on a case-by-case basis that are judged unlikely to affect the PK profile of the study 
drug or participant safety (e.g., topical drug products without significant systemic absorption). 
If vaccination is required for any reason, it must first be discussed with and exempted by the 
Investigator on a case-by-case basis to ensure that it does not compromise the PK profile of the 
study drug or the participant safety. 
Medications taken by participants before dosing will be documented as prior medications and 
medications taken by participants after dosing up to follow-up phone call will be documented as 
concomitant medications. Any prior or concomitant medication use, other than the allowed 
medications stated above, will be reviewed and evaluated on a case-by-case basis by the 
Investigator to determine if they affect a participant’s eligibility or continued participation in the 
study, or for potential impact on the study results. 
7.2 
Drugs, Nicotine and Alcohol 
Participants will be required to abstain from: 
• Soft or hard drugs from screening and throughout the study; 
• Any nicotine product from screening and throughout the study; 
• Alcohol-based products from 24 hours prior to admission until after the last PK blood 
sample collection of the study. 
7.3 
Diet 
Participants will be required to abstain from: 
• Food or beverages containing grapefruit, Seville orange, starfruit, pomegranate, 
pineapple, or pomelo from 7 days prior to first dosing until after the last PK blood sample 
collection of the study; 

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• Food or beverages containing xanthine derivatives or xanthine-related compounds 
(coffee, black/green tea, chocolate) or energy drinks from 48 hours prior to first dosing 
until after the last PK blood sample collection of the study; 
• Food containing poppy seeds from 24 hours prior to admission. 
7.4 
Posture and Physical Activity 
Part 1: 
Participants will be allowed to engage in normal activity but will avoid lying down or sleeping 
for 4 hours after camlipixant administration on Day 1. On Day 11, participants will be allowed to 
engage in normal activity but will avoid lying down or sleeping for 5 hours after rifampin 
administration. On Days 4 to 10 and Day 12, participants will be allowed to engage in normal 
activity but will avoid lying down or sleeping for 4 hours after each rifampin administration. 
Participants will be required to refrain from strenuous exercise at least 3 days before admission 
and throughout the study. 
Part 2: 
Participants will be allowed to engage in normal activity but will avoid lying down or sleeping 
for 4 hours after camlipixant administration on Day 1. On Day 4, participants will be required to 
remain seated or semi-reclined and will avoid lying down or sleeping for 4 hours after 
rabeprazole administration. On Day 10, participants will be required to remain seated or 
semi-reclined and will avoid lying down or sleeping for 5 hours after rabeprazole administration. 
On Days 5 to 9 and Day 11, participants will be allowed to engage in normal activity but will 
avoid lying down or sleeping for 4 hours after each rabeprazole administration. 
Participants will be required to refrain from strenuous exercise at least 3 days before admission 
and throughout the study. 
8. 
Study Procedures 
Participants must provide written informed consent prior to initiation of any study procedures. 
Unless otherwise specified, study procedures will be conducted in accordance with clinical site 
SOPs. From screening through the follow-up phone call, participants will undergo study 
procedures at pre-defined times as specified in Table 1. 
Schedule of Assessments for Part 1 
and Table 2. Schedule of Assessments for Part 2 and as described in sections 8.1, 8.2, and 8.3. 
Every effort will be made to schedule and perform the procedures as close to the nominal time as 
possible, giving considerations to appropriate posture conditions, practical restrictions, and other 
procedures to be performed at the same time point. 
PK blood sample collection will be performed closest to the nominal time. When vital signs 
measurement or ECG recording coincide with a blood collection, they should preferably be 
performed before the blood collection, whenever possible. Sample collections done outside the 

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pre-defined time windows will not be considered as protocol deviations since actual post-dose 
sampling times will be used for PK and statistical analyses. 
8.1 
Pharmacokinetic Assessments 
8.1.1 
Pharmacokinetic Blood Sample Collection and Processing 
Blood samples for PK analysis will be collected via an intravenous catheter or by direct 
venipuncture at the time points indicated in Table 1. Schedule of Assessments for Part 1 and 
Table 2. 
Schedule of Assessments for Part 2. Applicable time windows for PK blood 
samples are defined in the tables below. 
Table 3. 
Time Windows for PK Blood Samples for Part 1 
Day 
Time point (camlipixant) 
Time point (rifampin) 
Time window 
1 and 11 
Pre-dose 
Pre-dose (Day 11) 
Within 30 minutes 
0.16, 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 
4, and 6 hours 
- 
±1 minute 
8, 10, 12, 15, and 18 hours 
- 
±3 minutes 
2 and 12 
24 and 36 hours 
- 
±5 minutes 
3 and 13 
48 hours 
- 
±10 minutes 
4, 8, 9, and 10 
Not applicable 
Pre-dose 
Within 30 minutes 
 
Table 4. 
Time Windows for PK Blood Samples for Part 2 
Day 
Time point (camlipixant) 
Time point 
(rabeprazole) 
Time window 
1 and 10 
Pre-dose 
Pre-dose (Day 10) 
Within 30 minutes 
0.16, 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 
4, and 6 hours 
- 
±1 minute 
8, 10, 12, 15, and 18 hours 
- 
±3 minutes 
2 and 11 
24 and 36 hours 
- 
±5 minutes 
3 and 12 
48 hours 
- 
±10 minutes 
4, 7, 8, and 9 
Not applicable 
Pre-dose 
Within 30 minutes 
 
The planned volume of blood to be collected for this study, including that collected for eligibility 
and safety purposes, should not exceed 200 mL in Part 1 and 200 mL in Part 2. Additional tests 
or blood draws could be performed, if deemed required by the Investigator or study staff. 
Procedures for collection and processing of PK blood samples will be detailed in a separate 
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Plasma concentrations of the study drug will be determined using a validated analytical method. 
Details of the analytical method will be provided in a separate document. 
8.2 
Pharmacogenomic Assessments 
One blood sample for pharmacogenomic analysis will be collected upon admission on Day -1 in 
both Part 1 and Part 2. 
8.3 
Safety and Tolerability Assessments 
Part 1: 
Participants will be monitored throughout the study by the clinical staff for AEs/SAEs. On 
Day 1, the Investigator or designee will be on site for camlipixant administration and until 
4 hours post-dose. On Day 4, the Investigator or designee will be on site for rifampin 
administration and until 4 hours post-dose. On Day 11, the Investigator or designee will be on 
site for rifampin administration and camlipixant administration and until 4 hours post-dose of 
camlipixant. The Investigator or designee will be available on call for the remainder of the study. 
Part 2: 
Participants will be monitored throughout the study by the clinical staff for AEs/SAEs. On 
Day 1, the Investigator or designee will be on site for camlipixant administration and until 
4 hours post-dose. On Day 4, the Investigator or designee will be on site for rabeprazole 
administration and until 4 hours post-dose. On Day 10, the Investigator or designee will be on 
site for rabeprazole administration and camlipixant administration and until 4 hours post-dose of 
camlipixant. The Investigator or designee will be available on call for the remainder of the study.  
Parts 1 and 2: 
If necessary, the Investigator or designee at the clinical site or a healthcare professional in a 
nearby hospital will administer treatment for any AEs/SAEs. A crash cart or emergency bag 
containing the necessary rescue material and appropriate medications will be available in the 
clinic to allow rapid intervention in case of emergency. 
Safety parameters will be assessed by the Investigator or designee, using the clinical site 
acceptance ranges as suggested guidelines in making the medical assessment. 
For eligibility purposes, abnormal vital signs measurements or clinical laboratory test results 
may be repeated once if an abnormal result is observed at the initial reading. Moreover, 
abnormalities found in the ECG may need to be confirmed by repeated measurements. In the 
event that the participation of a participant in the study is delayed and some screening procedures 
had been performed outside of the prescribed screening window, outdated screening procedures 
can be repeated. 
Safety assessments scheduled during the study will be repeated according to the clinical site 
SOPs or upon request from the Investigator or designee. Any abnormal repeated measurement 
will be evaluated and repeated, if judged necessary. Further action may be taken upon the 
Investigator or designee’s request. 

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8.3.1 
Physical Examination 
Physical examinations will be performed at the times specified in Table 1. Schedule of 
Assessments for Part 1 and Table 2. Schedule of Assessments for Part 2. 
A complete physical examination will include assessments of the following: head, eyes, ears, 
nose, throat (HEENT), neck, chest, lungs, abdomen, musculoskeletal, dermatological, 
cardiovascular/peripheral vascular, and general neurological examination. 
A brief physical examination will include assessments of the following: HEENT, chest, lungs, 
abdomen, dermatological, cardiovascular/peripheral vascular, and areas of note elicited from the 
participant. 
8.3.2 
Body Measurements 
Body measurements will be performed at screening and will include body weight and height 
measurements, as well as BMI calculation. 
8.3.3 
Vital Signs 
Blood pressure, heart rate, respiratory rate, and oral temperature will be measured after the 
participants have been resting for at least 5 minutes in a sitting position at the times specified in 
Table 1. 
Schedule of Assessments for Part 1 and Table 2. 
Schedule of Assessments for 
Part 2. 
8.3.4 
12-lead ECG 
Standard 12-lead ECG will be recorded after the participants have been resting for at least 
5 minutes in a semi-recumbent or supine position at the times specified in Table 1.
 
Schedule of Assessments for Part 1 and Table 2. 
Schedule of Assessments for Part 2.  
8.3.5 
Laboratory Assessments 
Blood and urine samples for clinical laboratory assessments will be collected according to the 
clinical site SOPs at the times specified in Table 1. Schedule of Assessments for Part 1 and 
Table 2. 
Schedule of Assessments for Part 2. The clinical laboratory assessments to be 
performed are listed in the table below. In case of abnormal results, additional testing may be 
conducted at the discretion of the Investigator. 

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Table 5. 
Clinical Laboratory Assessments 
Biochemistry 
Hematology 
Urinalysis 
Albumin 
Alkaline phosphatase 
ALT 
AST 
Calcium 
Chloride 
Creatine kinase 
Creatinine 
GGT 
Glucose 
Phosphorus 
Potassium  
Sodium 
Total, direct and indirect bilirubin1 
Total protein 
Urea (BUN) 
Uric acid 
 
Hematocrit 
Hemoglobin 
Platelet count 
RBC count 
WBC count and differential: 
• 
Basophils 
• 
Eosinophils 
• 
Lymphocytes 
• 
Monocytes 
• 
Neutrophils 
Bilirubin 
Blood (occult) 
Color and appearance 
Glucose 
Ketones 
Leukocyte esterase 
Nitrite 
pH 
Protein 
Specific gravity 
Urobilinogen 
Microscopic examination (in the 
event of abnormal findings) 
Coagulation2 
aPTT 
PT 
INR 
Serology 
Drug, cotinine, and alcohol 
screens 
Hormone panel - females only 
HBsAg 
HCV antibody 
HIV antigen/antibody 
 
Amphetamines/methamphetamines 
Barbiturates 
Benzodiazepines 
Cocaine 
MDMA 
Methadone 
Opiates 
PCP 
THC 
 
Urine cotinine test 
Alcohol breath test 
FSH (post-menopausal females 
only) 
Serum pregnancy test 
Urine pregnancy test 
Abbreviations: ALT = alanine aminotransferase; aPTT = activated partial thromboplastin time; AST = aspartate 
aminotransferase; BUN = blood urea nitrogen; FSH = follicle-stimulating hormone; GGT = gamma-glutamyl 
transferase; HBsAg = hepatitis B surface antigen; HCV = hepatitis C virus; HIV = human immunodeficiency virus; 
INR = international normalized ratio; MDMA = 3,4- methylenedioxymethamphetamine; PCP = phencyclidine; PT = 
prothrombin time; RBC = red blood cell; THC = tetrahydrocannabinol; WBC = white blood cell. 
1 
Considering that indirect bilirubin is calculated from total and direct bilirubin values, indirect bilirubin result 
would not be available in case of total or direct bilirubin below the limit of quantification. 
2 
If the coagulation tests results come back normal but the LFTs results are still abnormal after the repeat, the 
coagulation tests may be repeated upon Investigator’s judgement. 

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8.3.6 
Follow-up Phone Call 
A follow-up phone call will be performed at the times specified in Table 1.Schedule of 
Assessments for Part 1 and Table 2. Schedule of Assessments for Part 2, to ensure the ongoing 
wellbeing of participants after discharge. 
8.4 
Adverse Events and Serious Adverse Events 
8.4.1 
Definition of Adverse Event 
An AE is defined as any untoward medical occurrence in a participant who is administered a 
pharmaceutical product and which does not necessarily have a causal relationship with the 
treatment. An AE can, therefore, be any unfavorable and unintended sign (including an abnormal 
laboratory finding, for example), symptom, or disease temporally associated with the use of a 
medicinal (investigational) product, whether or not considered related to the medicinal 
(investigational) product. 
8.4.2 
Definition of Adverse Events of Medical Interest 
AEMIs are AEs of scientific interest specific to the drug class. They are required to be monitored 
closely and reported by the Investigator to the Sponsor promptly, regardless of relationship, 
severity, expectedness, and seriousness.  
AEMIs for this study include the following, but not limited to: 
The incidence of AEMIs of camlipixant alone from Day 1 to Day 4 pre-dose of rifampin (Part 1) 
or rabeprazole (Part 2) will act as a baseline.  
AEMIs appearing following rifampin administration alone from Day 4 to Day 11 pre-dose of 
camlipixant (Part 1) and rabeprazole administration alone from Day 4 to Day 10 pre-dose of 
camlipixant (Part 2) will be accounted for causality based on their onset date/time.  
8.4.3 
Definition of Serious Adverse Event 
A SAE is defined as any untoward medical occurrence that, at any dose: 
• Results in death; 
• Is life-threatening; 
• Requires inpatient hospitalization or prolongation of existing hospitalization; 
• Results in persistent or significant disability/incapacity; 
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• Is a congenital anomaly/birth defect, or; 
• Is otherwise considered to be an important medical event (IME) that may not be immediately 
life-threatening or result in death or hospitalization but may jeopardize the patient or may 
require intervention to prevent one of the other outcomes listed in the definition above. 
Medical and scientific judgement should be exercised in deciding whether an event should be 
considered as an IME. 
The Sponsor can upgrade an event at any time; downgrade is not permitted at any time.  
If a SAE occurs to a participant on this study, contact the Sponsor personnel listed in 
Section 8.4.6. 
8.4.4 
Assessment of Severity 
The severity will be described and documented using the following definitions: 
Table 6. 
Severity Scale 
Severity 
Description 
Mild 
Awareness of signs and symptoms but are easily tolerated; are of minor irritant type; 
causing no limitations of usual activities. Signs or symptoms may require minor 
action. 
Moderate 
Discomfort severe enough to cause some limitations of usual activities and may 
require action. 
Severe 
Incapacitating with inability to carry out usual activities or significantly affects 
clinical status, and requires specific action and/or medical attention. 
 
8.4.5 
Assessment of Relationship to Study Drug 
Each AE/SAE must be classified based on medical judgment and according to the following 
relationship categories: definite, probable, possible, unlikely, and not related. Causality 
assessments will need to be applied to the study drug and interacting drug the participant has 
been administered. The definitions for the relationship categories are as follows: 

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Table 7. 
Relationship Categories 
Assessment 
Definition 
Definite 
A clinical event, including laboratory test abnormality, occurring in a plausible time 
relationship to drug administration and which cannot be explained by concurrent 
disease or other drugs or chemicals. The response to withdrawal of the drug 
(de-challenge) should be clinically plausible. The event must be definitive 
pharmacologically or phenomenologically using a satisfactory re-challenge (the drug 
is re-administered to determine if the same reaction occurs) procedure if necessary. 
Probable 
A clinical event, including laboratory test abnormality, occurring in a plausible time 
relationship to drug administration and which cannot be explained by concurrent 
disease or other drugs or chemicals. The response to withdrawal of the drug 
(de-challenge) should be clinically plausible. 
Possible 
A clinical event, including laboratory test abnormality, with a reasonable time 
sequence to the drug administration, but which could also be explained by concurrent 
disease or other drugs or chemicals. Information on drug withdrawal may be lacking 
or unclear. 
Unlikely 
A clinical event, including laboratory test abnormality, with a temporal relationship 
to drug administration which makes a causal relationship improbable and in which 
other drugs, chemicals or underlying disease provide plausible explanations. 
Not related 
Any event that does not meet the above criteria; there is sufficient information that 
aetiology of the event is in no relation to the study drug. 
 
8.4.6 
Event Reporting 
All safety events will be recorded and evaluated for their seriousness, severity, and relationship 
to the study drug and the interacting drug. Safety events will be collected and documented 
starting from the time of signing the informed consent form (ICF), throughout the study, and 
until the follow-up phone call.  
After the initial AE/SAE report, the Investigator is required to proactively follow up with each 
participant at all subsequent visits or contact. All events will be followed up until the resolution, 
stabilization, the event is otherwise explained, or the participant refuses to provide additional 
information (documented as lost to follow-up). 
At any point after completion of the study, if a participant experiences an SAE that is considered 
by the Investigator to be either Definite, Probable, or Possible to study drug, this needs to be 
submitted to the Sponsor as described within. 
Safety events will be reported within 24 hours of learning of the event, using the appropriate 
reporting forms (SAE Form or Pregnancy Form). The notification must be directed to: 
 
Drug Safety and Pharmacovigilance 
And to: 
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Blank copies of the forms are included in the study Investigator’s file. It is not acceptable for the 
Investigator to send photocopies of the patient’s medical records to the Sponsor company or its 
representative in lieu of completion of the appropriate AE eCRF page or SAE Report Form. 
However, there may be instances when copies of medical records for certain cases are requested 
by the Sponsor or its representative. In this instance, all participant identifiers will be blinded on 
the copies of the medical records before submission to the Sponsor or its representative.  
If the Investigator does not have all information regarding an SAE, he/she will not wait to 
receive additional information before completing and sending the form. 
Follow-up reports (as many as required) should be completed and faxed/e-mailed following the 
same procedure above. The Investigator should follow the participant with the event until 
resolution or stabilization of the condition. 
The Investigator must keep a copy of all documentation related to the event in the clinical site 
files. 
8.4.6.1 
Suspected Unexpected Serious Adverse Event Reporting to the IEC and 
Regulatory Agency(ies) 
It is the responsibility of the clinical site to report suspected, unexpected, serious adverse 
reactions (SUSARs) to the IEC responsible for the study per their policies. Report of fatal or 
life-threatening SUSARs must be made as soon as possible, but no later than 7 calendar days 
after first knowledge of the event. Report of SUSARs that are neither fatal nor life-threatening 
must be made as soon as possible, but no later than 15 calendar days after first knowledge of the 
event. 
The Sponsor (or representative) is responsible for notifying the regulatory agency(ies) of 
SUSARs observed during the study conduct per their regulations, as soon as possible but no later 
than 7 calendar days after becoming aware of the information when fatal or life-threatening, or 
15 calendar days when neither fatal nor life-threatening. The Sponsor (or representative) is 
responsible to comply with any other applicable regulatory requirement(s) related to the 
reporting of SAE to other regulatory authority(ies). 
8.4.7 
Pregnancy Reporting 
In the event a dosed female participant or the female partner of a dosed male participant (i.e., has 
received at least one dose of the investigational product) becomes pregnant during or up to 
30 days after the last dose, this pregnancy will be reported to the Sponsor (or representative) 
within 24 hours of first knowledge of the event as described in Section 8.4.6. The applicable 
Pregnancy Notification and Outcome forms will be used.  
Any participant who becomes pregnant during the study will be immediately withdrawn. 
Follow-up information regarding the course and outcome of the pregnancy will be documented 
(after obtaining the consent of the female partner) as per site’s SOP.  
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If at any time during the pregnancy or the outcome of the pregnancy, the participant and/or baby 
experiences an AE that meets the criteria of an SAE and/or reportable event, reporting of the 
event to the IEC responsible for the study and/or to applicable regulatory agency(ies) will be 
performed as per site’s SOP and country-specific reporting requirement. 
8.4.8 
Overdose Reporting 
Although unlikely to occur as study drug is administered as a single dose under direct 
supervision, should a participant experience an overdose (with or without an AE/SAE), protocol 
deviation will need to be documented and reported promptly to the Sponsor. 
8.5 
Premature Termination of the Study 
The study may be prematurely terminated by the Investigator following consultation with the 
Sponsor, by the Sponsor or by the regulatory authorities. Following a decision to discontinue the 
trial, the Investigator will promptly inform the active study participants and the IEC responsible 
for this trial, stating the reasons for discontinuation of the study. It is the responsibility of the 
Sponsor (or representative) to report the premature termination of the study to the regulatory 
authority(ies), when required by the applicable regulatory requirement(s). 
9. 
Statistical Analyses 
A complete description of the statistical analyses to be performed on PK as well as safety and 
tolerability data will be presented in a statistical analysis plan (SAP). 
9.1 
Analysis Populations 
9.1.1 
Safety Population 
The safety population is defined as all participants who receive at least one dose of the study 
drug. 
9.1.2 
Pharmacokinetic Concentration Population 
The pharmacokinetic concentration (PC) population for camlipixant will include all participants 
who received at least one dose of camlipixant drug at Day 1 or Day 11 (Part 1)/Day 10 (Part 2) 
and have at least one reportable concentration. 
9.1.3 
Pharmacokinetic Parameter Population 
The PK parameter population will include all participants for whom the Day 1 and Day 11 
(Part 1) or Day 10 (Part 2) PK profiles of the victim drug camlipixant can be adequately 
characterized, specifically, when administered alone and in combination with rifampin (Part 1) or 
rabeprazole (Part 2). 

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Any participant who experienced emesis during the sampling interval will be evaluated on a 
case-by-case basis in order to determine whether the participant will be excluded from the 
descriptive statistics and statistical analysis. 
Here are some aspects to be considered (but not to be limited to) when determining data 
availability for the PK population: inclusion and exclusion criteria, acceptable times for visit 
dates and measurements, compliance with camlipixant treatment, compliance with rifampin 
(Part 1) or rabeprazole (Part 2) treatment impacting camlipixant PK (number of doses received 
equal to 9 [Part 1] or 8 [Part 2]), 1-hour time interval between rifampin and camlipixant dosing 
on Day 11 of Part 1 or 1-hour time interval between rabeprazole and camlipixant dosing on 
Day 10 of Part 2, the nature and quality of the data, withdrawal, and any protocol deviation. The 
final responsibility of deciding which participants are to be included or excluded lies with the 
Investigator and/or the Sponsor. 
9.1.4 
Pharmacogenomic Population 
The pharmacogenomic population is defined as all participants in the safety population who had 
at least one pharmacogenomic measurement data available. 
9.2 
Pharmacokinetic Parameters 
The following PK parameters will be calculated based on the PK population by standard 
non-compartmental methods for camlipixant: 
• AUC0-t: Area under the concentration-time curve from time zero until the last observed 
concentration 
• AUC0-inf: Area under the concentration-time curve from time zero to infinity 
(extrapolated) 
• Residual area: Percentage of AUC0-inf due to extrapolation from the time of the last 
observed concentration to infinity, calculated as [1 – (AUC0-t/AUC0-inf)] x 100 
• Cmax: Maximal observed concentration 
• Tmax: Time when the maximal concentration is observed 
• T½ el: Terminal elimination half-life 
• Kel: Terminal elimination rate constant 
• Cl/F: Apparent clearance 
• Vz/F: Apparent volume of distribution 
The following information will be presented for rifampin (Part 1): pre-dose concentrations on the 
morning of Days 4, 8, 9, 10, and 11. 
The following information will be presented for rabeprazole (Part 2): pre-dose concentrations on 
the morning of Days 4, 7, 8, 9, and 10. 
Additional PK parameters may be calculated. 

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9.3 
Pharmacokinetic Statistical Analysis 
Statistical analysis described in this section will be based on the PK parameter population. 
Individual and mean plasma concentration versus time curves will be presented for both linear 
and semi-log scales. Descriptive statistics (arithmetic and geometric means, standard deviation 
[SD], CV%, minimum [Min], maximum [Max], and median) of the plasma concentrations versus 
time will be presented as well for the PK parameters. 
Concentrations for rifampin (Part 1) and rabeprazole (Part 2) will be tabulated. They will be 
presented as supportive data. Descriptive statistics on pre-dose concentrations of rifampin in 
Part 1 (Days 9, 10, and 11) and rabeprazole in Part 2 (Days 8, 9, and 10) will be performed to 
evaluate the attainment of steady-state. 
Additional PK statistical analysis may be performed. 
A SAP will be prepared after completion of the final protocol and prior to database lock. 
9.4 
Criteria for No Drug-Drug Interaction for Camlipixant 
 
 
 
9.5 
Safety and Tolerability Analysis 
Demographic parameters will be summarized descriptively. 
Safety and tolerability analysis will be performed for all participants in the safety population. No 
inferential statistical analysis of safety data is planned. 
Safety and tolerability of camlipixant alone and in combination with rifampin (Part 1) or 
rabeprazole (Part 2) will be evaluated through the assessment of AEs, SAEs, AEMIs (i.e., 
seriousness, severity, relationship to the study drug and the interacting drug, outcome, duration, 
and management), vital signs, 12-lead ECGs, clinical laboratory tests, and physical 
examinations. AEs will be coded using the latest version of the Medical Dictionary for 
Regulatory Activities (MedDRA). 
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Concomitant medications will be coded using the most current version of World Health 
Organization drug (WHODrug) dictionary available.  
Note that both MedDRA and WHODrug dictionaries are updated twice annually. 
TEAEs will be tabulated by treatment. Changes from baseline values in vital signs, 12-lead 
ECGs, and clinical laboratory tests will be evaluated. Safety and tolerability data will be reported 
using descriptive statistics. 
9.6 
Pharmacogenomic Evaluation 
 Other possible 
exploratory markers may be considered as deemed necessary. 
10. Data Collection 
The source data will be collected mainly on paper as per site SOPs. Source data should be 
attributable, legible, contemporaneous, original, accurate, and complete. Source documents will 
be maintained in order to maintain data integrity. The Investigator and/or the clinical staff have 
the responsibility of ensuring the accuracy, completeness, legibility, and timeliness of the source 
data. 
Source data will be transcribed by the clinical site in the RAVE electronic data capture system 
electronic case report form (eCRF) designed to capture study protocol required data. Vendor data 
will be received electronically and will be reconciled with eCRF data. Details on the data 
management process will be described in a data management plan (DMP). 
11. Regulatory Considerations and Quality Assurance 
11.1 IEC Approval of Protocol and Other Study Documents 
The Investigator(s) agree to provide the IEC with all appropriate documents, including a copy of 
the protocol/amendments, ICFs, advertising text (if any), Investigator’s Brochure (if any), and 
any other written information provided to study participants. The trial will not begin until the 
Investigators have obtained the IEC favourable written approvals for the above-mentioned study 
documents. A properly executed written ICF shall be read, signed, and dated by each participant 
prior to entering the trial or prior to performing any study procedure. The original signed and 
dated ICF will be kept at the clinical site and a copy will be given to the participant. 
In the event that the protocol is amended, the revised protocol must be approved by the IEC prior 
to its implementation, unless the changes involve only logistical or administrative aspects of the 
trial. If a revised ICF is introduced during the study, each participant’s further consent must be 
obtained. The new version of the ICF must be approved by the IEC, prior to subsequently 
obtaining each participant’s consent. 
The Investigator and the Sponsor’s representative must sign the protocol and its amendments (if 
any) before initiating the study. 
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It is the Sponsor’s responsibility to submit the protocol and its amendments (if any), and the 
ICFs to regulatory authorities when necessary. This task has been delegated to the contract 
research organization (CRO). 
11.2 Compliance 
This study will be conducted in compliance with the protocol, GCP ICH E6 (R2), all applicable 
regulations, including the Federal Food, Drug and Cosmetic Act, U.S. applicable Code of 
Federal Regulations (title 21), and any IEC requirements relative to clinical studies. The study 
will also be conducted in compliance with the recommendations laid down in the most recent 
version of the Declaration of Helsinki, with the exception that registration of such Phase 1 trials 
in a publicly accessible database is not mandatory. As required by the Canadian regulatory 
agency, a Clinical Trial Application (CTA) will be submitted before the beginning of the study 
and a No Objection Letter (NOL) must be received prior to dosing. 
11.3 Quality Assurance and Monitoring 
The Sponsor or its designee will perform the quality assurance and quality control activities of 
this study; however, responsibility for the accuracy, completeness, security, and reliability of the 
study data presented to the Sponsor lies with the Investigator generating the data. When 
applicable, quality assurance procedures will be performed according to the site SOPs. 
The study will be monitored according to the Sponsor monitoring plan and SOP to ensure that it 
is conducted and documented properly according to the protocol, GCP, and all applicable 
regulatory requirements. The Sponsor is entitled to access information about the status of the 
study and to review the original documents of the study. 
The Sponsor may arrange audits as part of the implementation of quality assurance to ensure that 
the study is being conducted in compliance with the protocol, SOPs, GCP, and all applicable 
regulatory requirements. In such case, audits will be independent of and separate from the 
routine monitoring and quality control functions. 
11.4 Confidentiality and Retention of Study Records 
This document contains trade secrets and commercial information that is confidential and may 
not be disclosed to third parties. Persons to whom this study protocol is disclosed must be 
informed that all the information herein is confidential and may not be further divulged. These 
restrictions will apply as well to all future communications if deemed privileged or confidential. 
Publication of the study results may only be allowed with written permission from the Sponsor. 
All information on a participant obtained during the conduct of the study will be kept 
confidential. Participants will be identified by an anonymized identifier on all samples and study 
records provided to the Sponsor or designee. In compliance with ICH GCP, the Sponsor’s 
authorized representatives, monitor(s), auditor(s), IEC, and regulatory authority(ies) will be 
granted direct access to the participant’s original trial-related records for verification of clinical 
trial procedures and/or data, without violating the confidentiality of the participant, to the extent 
permitted by the applicable laws and regulations. Consent from the participant for disclosure of 

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such information will be obtained in writing in the ICF. In addition, should a participant require 
medical care or hospitalization during the course of the study, the clinical site may contact the 
treating physician with the participant’s consent, except that consent may not be requested if 
there is an emergency situation. If the results of the study are published, the participant’s identity 
will remain confidential. 
The clinical site will maintain adequate study records for 25 years after completion or 
termination of study. The Sponsor will be notified prior to the destruction of study records. 

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12. References 
1 
BLU-5937. Investigator’s Brochure. Bellus Health Inc. 5th Edition (version dated April 
22nd, 2022) and Addendum Version 5.0 (dated April 19th, 2022). 
2 
Bellus Health Inc. A 24-Week Study of the Efficacy and Safety of BLU-5937 in Adults 
With Refractory Chronic Cough (CALM-2). ClinicalTrials.gov identifier: NCT05600777. 
Updated: March 6, 2023. 
https://clinicaltrials.gov/ct2/show/NCT05600777?term=5937&cond=refractory+chronic+
cough&draw=2&rank=3 
3 
Bellus Health Inc. A 52-Week Study of the Efficacy and Safety of BLU-5937 in Adults 
With Refractory Chronic Cough (CALM-1). ClinicalTrials.gov identifier: NCT05599191. 
Updated: March 6, 2023. 
https://clinicaltrials.gov/ct2/show/NCT05599191?term=5937&cond=refractory+chronic+
cough&draw=2&rank=2 
4 
A Phase I, Double-Blind, Randomized, Adaptive-designed Study to Assess the 
Pharmacokinetics and Safety of BLU-5937 in Healthy Adult Japanese and Caucasian 
Subjects Following Single and Multiple Oral Doses. BUS-P1-07/C20042. Clinical Study 
Report. Bellus Health. 11 November 2022. 
5 
ROFACT®, Product Monograph. Version revised on June 28, 2019. Drug Product 
Database, Health Canada. Available online at: health-products.canada.ca/dpd-
bdpp/index-eng.jsp 
6 
Rifampin Capsules USP, Drug Label Information. Version revised: April 2022. Available 
online at: dailymed.nlm.nih.gov/dailymed/index.cfm 
7 
PARIET®, Product Monograph. Version revised on August 8, 2022. Drug Product 
Database, Health Canada. Available online at: health-products.canada.ca/dpd-
bdpp/index-eng.jsp 
8 
Center for Drug Evaluation and Research (CDER), FDA. Guidance for Industry: Clinical 
Drug Interaction Studies – Cytochrome P450 Enzyme- and Transporter-Mediated Drug 
Interactions. January 2020. 
9 
Drug Development and Drug Interactions: Table of Substrates, Inhibitors and Inducers. 
Content current as of 08/24/2022. Accessed on: https://www.fda.gov/drugs/drug-
interactions-labeling/drug-development-and-drug-interactions-table-substrates-inhibitors-
and-inducers#table4-2. 
10 
Center for Drug Evaluation and Research (CDER), FDA. Evaluation of Gastric 
pH-Dependent Drug Interactions With Acid-Reducing Agents: Study Design, Data 
Analysis, and Clinical Implications. November 2020. 
11 
Wedemeyer RS, Blume H. Pharmacokinetic drug interaction profiles of proton pump 
inhibitors: an update. Drug Saf. 2014;37(4):201-211. 
12 
Kapetas AJ, Sorich MJ, Rodrigues AD, Rowland A. Guidance for Rifampin and 
Midazolam Dosing Protocols To Study Intestinal and Hepatic Cytochrome P450 (CYP) 
3A4 Induction and De-induction. AAPS J. 2019;21(5):78. Published 2019 Jun 19. 

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13 
Kalayci T, Erener-Ercan T, Buyukkale G, Cetinkaya M. Limb deformity in a newborn. Is 
rifampicin just an innocent bystander?. Eur Rev Med Pharmacol Sci. 2015;19(3):517-
519. 
 
 
 

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13. Appendix 1 
Summary Table for Part 1 
 
Procedures 
Screening 
• 
Informed consent 
• 
Inclusion/exclusion criteria 
• 
Demographic data 
• 
Medical and medication history 
• 
Complete physical examination 
• 
Body measurements (height, weight, BMI) 
• 
Vital signs (blood pressure, heart rate, respiratory rate, and oral temperature) 
• 
12-lead ECG 
• 
Serology (HBsAg, HCV antibody, and HIV antigen and antibody) 
• 
Biochemistry (including LFT and CK), hematology, coagulation, urinalysis 
• 
Drug, cotinine, and alcohol screens 
• 
Urine pregnancy test 
• 
FSH levels to confirm post-menopausal status 
• 
Monitoring of AE/SAE/AEMI 
D -1 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Start of confinement 
• 
Blood sample for pharmacogenomic analysis 
• 
Brief physical exam 
• 
Biochemistry (including LFT and CK), hematology, coagulation, urinalysis 
• 
Drug, cotinine, and alcohol screens 
• 
COVID-19 test 
• 
Serum pregnancy test 
D1 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
Single dose administration of camlipixant 50 mg tablet 
• 
Blood samples for PK analysis of camlipixant 
• 
Blood pressure and heart rate: before dosing 
• 
12-lead ECG: before dosing 
D2 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
Blood samples for PK analysis of camlipixant 
D3 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
COVID-19 test 
• 
Blood samples for PK analysis of camlipixant 
D4 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
 dose morning administration of capsules of rifampin 
 mg 
 
• 
Blood sample for PK analysis of rifampin 
• 
12-lead ECG: pre-dose of rifampin administration 
• 
Biochemistry (including LFT and CK), hematology, coagulation, and urinalysis: before dosing 
D5 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
dose morning administration of 2 capsules of rifampin 
mg 
 
D6 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
 dose morning administration of capsules of rifampin 
mg 
 
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• 
Biochemistry (including LFT and CK) before dosing 
D7 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
 dose morning administration of capsules of rifampin 
mg 
 
D8 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
 dose morning administration of capsules of rifampin 
 mg 
 
• 
Blood sample for PK analysis of rifampin 
D9 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
Multiple dose morning administration of
capsules of rifampin 
mg 
 
• 
Blood sample for PK analysis of rifampin 
• 
Biochemistry (including LFT and CK) before dosing 
D10 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
Multiple dose morning administration of  capsules of rifampin 
 mg 
 
• 
Blood sample for PK analysis of rifampin 
• 
Brief physical exam in the evening 
D11 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
Multiple dose morning administration of capsules of rifampin 
mg 
 
• 
Single dose administration of camlipixant 50 mg tablet 1 hour (± 2 minutes) after rifampin 
administration 
• 
Blood samples for PK analysis of camlipixant 
• 
Blood sample for PK analysis of rifampin 
• 
Blood pressure and heart rate: before rifampin dosing 
• 
12-lead ECG: before rifampin dosing 
• 
Biochemistry (including LFT and CK), hematology, coagulation and urinalysis before rifampin 
dosing 
D12 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
 dose morning administration of  capsules of rifampin 
mg 
 
• 
Blood samples for PK analysis of camlipixant 
D13 
Discharge or 
ET 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Brief physical exam 
• 
Vital signs (blood pressure, heart rate, respiratory rate, and oral temperature) 
• 
12-lead ECG 
• 
Biochemistry (including LFT and CK), hematology, coagulation, urinalysis 
• 
Urine pregnancy test 
• 
Blood samples for PK analysis of camlipixant 
• 
Discharge 
D20 ± 2 
• 
Follow-up phone call 
• 
Monitoring of AEs/SAEs/AEMIs and concomitant medications 
Abbreviations: AE = adverse event; AEMI = adverse event of medical interest; CK = creatine kinase; COVID-19 = 
coronavirus 2019; ECG = electrocardiogram; ET = early termination; FSH = follicle-stimulating hormone; HBsAg = 
hepatitis B surface antigen; HCV = hepatitis C virus; HIV = human immunodeficiency virus; LFT = liver function 
test; PK = pharmacokinetic, 
; SAE = serious adverse event. 
 
 
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Summary Table for Part 2 
 
Procedures 
Screening 
• 
Informed consent 
• 
Inclusion/exclusion criteria 
• 
Demographic data 
• 
Medical and medication history 
• 
Complete physical examination 
• 
Body measurements (height, weight, BMI) 
• 
Vital signs (blood pressure, heart rate, respiratory rate, and oral temperature) 
• 
12-lead ECG 
• 
Serology (HBsAg, HCV antibody, and HIV antigen and antibody) 
• 
Biochemistry (including LFT and CK), hematology, coagulation, urinalysis 
• 
Drug, cotinine, and alcohol screens 
• 
Urine pregnancy test 
• 
FSH levels to confirm post-menopausal status 
• 
Monitoring of AEs/SAEs/AEMIs 
D -1 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Start of confinement 
• 
Blood sample for pharmacogenomic analysis 
• 
Brief physical exam 
• 
Biochemistry (including LFT and CK), hematology, coagulation, urinalysis 
• 
Drug, cotinine, and alcohol screens 
• 
COVID-19 test 
• 
Serum pregnancy test 
D1 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
Single dose administration of camlipixant 50 mg tablet 
• 
Blood samples for PK analysis of camlipixant 
• 
Blood pressure and heart rate: before dosing 
• 
12-lead ECG: before dosing 
D2 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
Blood samples for PK analysis of camlipixant 
D3 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
COVID-19 test 
• 
Blood samples for PK analysis of camlipixant 
D4 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
dose 
 administration of rabeprazole
 mg enteric-coated tabled 
 
• 
Blood sample for PK analysis of rabeprazole 
• 
12-lead ECG: pre-dose 
• 
Biochemistry (including LFT and CK), hematology, coagulation, and urinalysis: before dosing 
D5 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
dose morning administration of rabeprazole 
mg enteric-coated tabled 
 
D6 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
 dose morning administration of rabeprazole 
mg enteric-coated tabled 
 
D7 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
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• 
 dose 
 administration of rabeprazole
 mg enteric-coated tabled 
 
• 
Blood sample for PK analysis of rabeprazole 
D8 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
 dose 
 administration of rabeprazole 
mg enteric-coated tabled 
 
• 
Blood sample for PK analysis of rabeprazole 
D9 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
 dose 
 administration of rabeprazole
 mg enteric-coated tabled 
 
• 
Blood sample for PK analysis of rabeprazole 
• 
Brief physical exam in the evening 
D10 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
dose 
 administration of rabeprazole 
mg enteric-coated tabled 
 
• 
Single dose administration of camlipixant 
mg tablet 1 hour (± 2 minutes) after rabeprazole 
administration 
• 
Blood samples for PK analysis of camlipixant 
• 
Blood sample for PK analysis of rabeprazole 
• 
Blood pressure and heart rate: before rabeprazole dosing 
• 
12-lead ECG: before rabeprazole dosing 
• 
Biochemistry (including LFT and CK), hematology, coagulation and urinalysis before 
rabeprazole dosing 
D11 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Continued confinement 
• 
 dose 
 administration of rabeprazole 
mg enteric-coated tabled 
 
• 
Blood samples for PK analysis of camlipixant 
D12 
Discharge or 
ET 
• 
Monitoring and recording of AEs/SAEs/AEMIs and concomitant medication use 
• 
Blood samples for PK analysis of camlipixant 
• 
Brief physical exam 
• 
Vital signs (blood pressure, heart rate, respiratory rate, and oral temperature) 
• 
12-lead ECG 
• 
Biochemistry (including LFT and CK), hematology, coagulation, urinalysis 
• 
Urine pregnancy test 
• 
Discharge 
D19 ± 2 
• 
Follow-up phone call 
• 
Monitoring of AEs/SAEs/AEMIs and concomitant medications 
Abbreviations: AE = adverse event; AEMI = adverse event of medical interest; CK = creatine kinase; COVID-19 = 
coronavirus 2019; ECG = electrocardiogram; ET = early termination; FSH = follicle-stimulating hormone; HBsAg = 
hepatitis B surface antigen; HCV = hepatitis C virus; HIV = human immunodeficiency virus; LFT = liver function 
test; PK = pharmacokinetic, 
 SAE = serious adverse event. 
 
 
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CCI - This section contained Clinical Outcome Assessment data collection questionnaires or indices, which are protected by third party copyright laws and 
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The GlaxoSmithKline group of companies 
 
Clinical Study Report 
 
 
Study Protocol Number: 220254 (BUS-P1-11) 
 
 
Page 3 of 4 
 
Protocol Administrative Letter dated 13-JUN-2023 
 
 
 

Protocol Administrative Letter for Early Phase Studies 
 
This document is confidential. 
Controlled Document ID: 2780E.00, Effective Date 29-Jul-2021 
Page 1 of 2 
Filing requirement: TMF 
Project: 220254 (Sponsor code: BUS-P1-11) 
Sponsor: Bellus Health 
CC: Final Protocol dated 03-APR-2023 
Date: 13-JUN-2023 
Study Title: A Phase 1, 2-Part, Open-label, Fixed-sequence Study Evaluating the Effect of 
Rifampin (Part 1) and Rabeprazole (Part 2) on the Pharmacokinetics of a Single Dose of 
Camlipixant (BLU-5937) 50 mg Tablet in Healthy Participants under Fasting Conditions 
  
This Protocol administrative letter intends to bring the following change to the above-mentioned 
final protocol. 
It should be clarified that safety events must be reported 
 responsible 
for pharmacovigilance and case processing, using an additional e-mail address. Therefore, the 
information on pages 52-53, under section 8.4.6 Event Reporting, has been modified as follows: 
From: 
 
Drug Safety and Pharmacovigilance 
 
 
And to: 
 
To: 
 
 
Bellus Health: 
 
Drug Safety and Pharmacovigilance 
 
 
And to: 
 
 
 
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Administrative Letter 
Sponsor: Bellus Health; Protocol No.: 220254 (BUS-P1-11) 
 
 
This document is confidential. 
Controlled Document ID: 2780E.00, Effective Date 29-Jul-2021 
Page 2 of 2 
Filing requirement: TMF 
Created by: 
, Clinical Research Scientist II   
   
Printed Name, Title 
  Signature 
  Date (dd-MMM-
YYYY) 
  
Jun 13, 2023
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The GlaxoSmithKline group of companies 
 
Clinical Study Report 
 
 
Study Protocol Number: 220254 (BUS-P1-11) 
 
 
Page 4 of 4 
 
Protocol Administrative Letter dated 20-JUL-2023 

Protocol Administrative Letter for Early Phase Studies 
This document is confidential. 
Controlled Document ID: 2780E.00, Effective Date 29-Jul-2021 
Page 1 of 1 
Filing requirement: TMF 
Project: 220254 (Sponsor code: BUS-P1-11) 
Sponsor: Bellus Health 
CC: Final Protocol dated 03-APR-2023 
Date: 20-JUL-2023 
Study Title: A Phase 1, 2-Part, Open-label, Fixed-sequence Study Evaluating the Effect of 
Rifampin (Part 1) and Rabeprazole (Part 2) on the Pharmacokinetics of a Single Dose of 
Camlipixant (BLU-5937) 50 mg Tablet in Healthy Participants under Fasting Conditions 
This Protocol administrative letter intends to bring the following change to the above-mentioned 
final protocol.  
On page 50, under section 8.4.2 Definition of Adverse Events of Medical Interest, it is stated that 
adverse events of medical interest (AEMIs) occurring until the end of the study discharge will 
require 
. This may be misinterpreted as the time of discharge 
from the clinic. However, as AEMIs are part of the secondary safety endpoints, they need to be 
reported and documented from camlipixant first dosing until the end of the study (i.e. until the 
follow-up phone call or early termination [if applicable]), just as any other adverse event. 
Therefore, AEMIs occurring up until the end of the study, and not only until discharge from the 
clinic, will require 
.  
The following sentence: 
 
 
 
Should read as: 
 
 
Created by: 
, Senior Clinical Research 
Scientist 
Printed Name, Title 
Signature 
Date (dd-MMM-
YYYY) 
Jul 20, 2023
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