A Randomised Double Blind, Placebo Controlled Study of the Efficacy of Topical Menthol for Pain Relief During Topical Photodynamic Therapy
Phase: PHASE4
Conditions: Actinic Keratosis
Sponsor: University of Dundee

 
 

 
 
  
 
 
 
Page 1 
 
 
Study Protocol 
A randomised double blind, placebo controlled study of the efficacy of topical 
menthol for pain relief during topical photodynamic therapy 
 
Study Acronym 
Menthol for PDT pain 
Sponsor 
University of Dundee 
Sponsor R&D Number 
2015PQ01 
Funder 
British Skin Foundation/ 
British Photodermatology Group 
Chief Investigator 
Professor Sally H. Ibbotson 
EudraCT Number 
2015-002849-59 
CTA Number 
      
REC Number 
     16/ES/0127  
Clinicaltrials.gov Number 
     NCT02984072 
Version Number and Date 
v.6.0 27/March/2019 
 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 2 
 
 
CONTENTS 
 
CONTENTS .............................................................................................................. 2 
PROTOCOL APPROVAL .......................................................................................... 4 
LIST OF ABBREVIATIONS ....................................................................................... 5 
SUMMARY ................................................................................................................ 6 
1 
INTRODUCTION ......................................................................................... 6 
1.1 
BACKGROUND .................................................................................. 6 
1.2 
RATIONALE FOR STUDY ................................................................ 10 
2 
STUDY OBJECTIVES ............................................................................... 10 
2.1 
OBJECTIVEs .................................................................................... 10 
2.1.1 
Primary Objective .................................................................... 10 
2.1.2 
Secondary Objectives .............................................................. 10 
2.2 
OUTCOMES ..................................................................................... 10 
2.2.1 
Primary Outcomes ................................................................... 10 
2.2.2 
Secondary Outcomes .............................................................. 11 
3 
STUDY DESIGN ........................................................................................ 11 
3.1 
STUDY DESCRIPTION .................................................................... 11 
3.2 
TRIAL FLOWCHART ........................................................................ 12 
3.3 
STUDY MATRIX ............................................................................... 13 
4 
STUDY POPULATION .............................................................................. 13 
4.1 
NUMBER OF PARTICIPANTS ......................................................... 13 
4.2 
INCLUSION CRITERIA .................................................................... 14 
4.3 
EXCLUSION CRITERIA ................................................................... 14 
5 
PARTICIPANT SELECTION AND ENROLMENT ..................................... 14 
5.1 
IDENTIFYING PARTICIPANTS ........................................................ 14 
5.2 
CONSENTING PARTICIPANTS ....................................................... 14 
5.3 
SCREENING FOR ELIGIBILITY ....................................................... 14 
5.4 
INELIGIBLE AND NON-RECRUITED PARTICIPANTS .................... 15 
5.5 
RANDOMISATION ........................................................................... 15 
5.5.1 
Randomisation ........................................................................ 15 
5.5.2 
Treatment Allocation ................................................................ 15 
5.5.3 
Emergency Unblinding ProceduresError! 
Bookmark 
not 
defined. 
5.5.4 
Withdrawal procedures ............................................................ 15 
6 
INVESTIGATIONAL MEDICINAL PRODUCT ........................................... 16 
6.1 
STUDY DRUG .................................................................................. 16 
6.1.1 
Study Drug Identification ......................................................... 16 
6.1.2 
Study Drug Manufacturer ........................................................ 16 
6.1.3 
Marketing Authorisation Holder ............................................... 16 
6.1.4 
Labelling and Packaging ......................................................... 16 
6.1.5 
Storage .................................................................................... 17 
6.1.6 
IMP Safety Information ............................................................ 16 
6.1.7 
Accountability procedures........................................................ 17 
6.2 
STUDY COMPARATOR ................................................................... 17 
6.2.1 
Comparator Identification......................................................... 17 
6.2.2 
Comparator Manufacturer........................................................ 17 
6.2.3 
Labelling and Packaging ......................................................... 17 
6.2.4 
Storage .................................................................................... 17 
6.2.5 
Accountability procedures........................................................ 17 
6.3 
DOSING REGIME ............................................................................ 17 
6.4 
DOSE CHANGES ................................ Error! Bookmark not defined. 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 3 
 
 
6.5 
PARTICIPANT COMPLIANCE ......................................................... 17 
6.6 
OVERDOSE ..................................................................................... 17 
6.7 
OTHER MEDICATIONS ................................................................... 17 
6.7.1 
Permitted Medications ............................................................. 17 
6.7.2 
Prohibited Medications ............................................................ 17 
6.7.3 
Concomitant Medications ........................................................ 18 
7 
STUDY ASSESSMENTS .......................................................................... 19 
7.1 
STUDY ASSESSMENTS .................................................................. 19 
7.2 
SAFETY ASSESSMENTS ................................................................ 19 
8 
DATA COLLECTION & MANAGEMENT .................................................. 18 
8.1 
Data Collection ................................................................................. 18 
8.2 
Data Management System ............................................................... 18 
9 
STATISTICS AND DATA ANALYSIS ....................................................... 18 
9.1 
SAMPLE SIZE CALCULATION ........................................................ 18 
9.2 
PROPOSED ANALYSES ................................................................. 19 
10 
ADVERSE EVENTS .................................................................................. 19 
10.1 
DEFINITIONS ................................................................................... 19 
10.2 
RECORDING AND REPORTING AEs AND SAEs ........................... 19 
10.3 
REGULATORY REPORTING REQUIREMENTS ............................. 20 
10.4 
ANNUAL REPORTING REQUIREMENTS  
 
 
  20 
10.5 
URGENT SAFETY MEASURES ....................................................... 20 
11 
PREGNANCY............................................................................................ 20 
12 
TRIAL MANAGEMENT & OVERSIGHT ARRANGEMENTS ..................... 21 
12.1 
TRIAL MANAGEMENT GROUP ....................................................... 21 
12.2 
TRIAL MANAGEMENT ..................................................................... 21 
12.5 
INSPECTION OF RECORDS ........................................................... 21 
12.6 
RISK ASSESSMENT ........................................................................ 21 
12.7 
STUDY MONITORING ..................................................................... 21 
    12.7.1 Potential risks ........................................................................................... 21 
12.7.2 
Minimising risk  ........................................................................ 21 
13 
GOOD CLINICAL PRACTICE ................................................................... 21 
13.1 
ETHICAL CONDUCT OF THE STUDY ............................................. 21 
13.1.1 
Confidentiality  ......................................................................... 21 
13.1.2 
Data protection ........................................................................ 22 
13.1.3 
Insurance & indemnity ............................................................. 22 
14 
STUDY CONDUCT RESPONSIBILITIES .................................................. 22 
14.1 
PROTOCOL AMENDMENTS ........................................................... 22 
14.2 
PROTOCOL DEVIATIONS, BREACHES, WAIVERS ....................... 23 
14.3 
STUDY RECORD RETENTION ....................................................... 23 
14.4 
END OF STUDY ............................................................................... 23 
14.5 
CONTINUATION OF DRUG FOLLOWING END OF STUDY ............ 23 
15 
REPORTING, PUBLICATION & NOTIFICATION OF RESULTS .............. 23 
15.1 
AUTHORSHIP POLICY .................................................................... 23 
15.2 
PUBLICATION ................................................................................. 23 
15.3 
PEER REVIEW ................................................................................ 23 
16 
REFERENCES .......................................................................................... 24 
APPENDICES 1 & 2 ............................................................................................... 26 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 4 
 
 
PROTOCOL APPROVAL 
A randomised double blind, placebo controlled study of the efficacy of topical 
menthol for pain relief during topical photodynamic therapy 
EudraCT number 2015-002849-59 
Signatures 
By signing this document I am confirming that I have read, understood and 
approve the protocol for the above study. 
 
Professor Sally H.  
Ibbotson 
 
20.11.19 
Chief Investigator 
Signature 
 
Date 
 
 
 
 
 
20.11.19 
Dr Robert S. Dawe 
 
 
Individual Responsible for 
Statistical Review 
Signature 
 
Date 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 5 
 
 
LIST OF ABBREVIATIONS 
(including Study abbreviations) 
 
GCP 
Good Clinical Practice 
IMP 
Investigational Medicinal Product 
TMF 
Trial Master File 
SOP 
Standard Operating Procedure 
CRF 
Case Report Form 
AE 
Adverse Event 
SAE 
Serious Adverse Event 
AR 
Adverse Reaction 
UAR 
Unexpected Adverse Reaction 
SUSAR 
Suspected Unexpected Serious Adverse Reaction 
CNORIS 
Clinical Negligence and Other Risks Scheme 
NRES 
National Research Ethics Service 
REC 
Research Ethics Committee 
MHRA 
Medicines and Healthcare Products Regulatory Authority  
PBU 
Photobiology Unit 
PDT 
Photodynamic Therapy 
NMSC 
Non-melanoma skin cancer 
VAS 
Visual analogue scale 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 6 
 
 
SUMMARY 
Topical photodynamic therapy (PDT) is widely used to treat superficial non-
melanoma skin cancer (NMSC) and dysplasia, notably actinic keratosis and may also 
be effective in a range of other dermatological conditions. A major limitation of PDT is 
pain during irradiation, which occurs in most and can be severe in ~20% of patients. 
A lack of knowledge of the mechanism of PDT-induced pain has limited the 
development of effective approaches for prevention or relief of this adverse effect. 
We developed a mouse model of PDT-induced pain that enabled us to determine the 
molecular mechanisms involved. Use of the model in combination with an in vitro 
assay of PDT-induced excitation of nociceptive neurons led to our identification of 
menthol as a potential analgesic agent for minimising PDT-pain. This proposal 
describes the prospective randomised double blind, placebo controlled clinical trial 
we will undertake in which we investigate the use of topical menthol for PDT-induced 
pain relief in patients with actinic keratosis of the face and scalp who will be attending 
general dermatology and PDT outpatient clinics at Ninewells Hospital, Dundee. 
 
This will be undertaken by comparison of 5% menthol in aqueous cream with 
aqueous cream as placebo and the primary outcome measures will be pain recorded 
on a visual analogue scale (VAS) during and up to 24 h after PDT. Secondary 
outcomes are phototoxicity, assessed by a semi-quantitative scoring system 
immediately after PDT, fluorescence assessed routinely after cream application and 
before irradiation and outcome based on clinical assessment three months after PDT 
and patient evaluation. Patients will be involved in the study from the first visit for 
PDT until the three-month assessment visit after PDT.  Data analysis will be 
undertaken using within-subject paired analyses as patients act as their own control. 
Information from this study will inform us as to whether we should or should not 
incorporate topical menthol into PDT treatment regimens routinely in order to reduce 
pain and increase tolerance of treatment. The information will also provide us with 
additional information as to the mechanisms of PDT-induced pain and its possible 
prevention and/or relief. 
 
1.0 
INTRODUCTION 
1.1 
 BACKGROUND 
Overview of background and purpose to the study 
Topical photodynamic therapy (PDT) is widely used to treat superficial non-
melanoma skin cancer (NMSC) and dysplasia, notably actinic keratosis (AK) and 
may also be effective in a range of other dermatological conditions [1, 2].  
Topically applied 5-aminolaevulinic acid (ALA), or its methyl ester (MAL), is absorbed 
(preferentially by diseased skin) and metabolised to the photosensitiser, 
protoporphyrin IX (PpIX) [3]. Irradiation during PDT causes photobleaching of PpIX 
and production of reactive oxygen species (ROS), particularly singlet oxygen, 
initiating cell destruction. A major limitation of PDT and the primary reason for lack of 
successful treatment delivery and refusal of therapy is pain during irradiation, which 
occurs in most and can be severe in ~20% of patients [3, 4]. A lack of knowledge of 
the mechanism of PDT-induced pain has limited the development of effective 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 7 
 
 
approaches for prevention or relief of this adverse effect [3-5]. The use of low 
irradiance light delivery may limit pain but requires prolonged treatment times and is 
only applicable in specific situations and is not feasible for most patients treated with 
PDT [6, 7]. It is also unclear whether the choice of photosensitiser pro-drug 
influences pain severity. Clinical studies suggest that MAL use is either associated 
with less severe PDT-induced pain than the use of ALA [4, 8, 9] or that there is no 
difference between treatments [10, 11]. The European Medicines Agency has 
recently approved Ameluz® (BF-200 ALA) for PDT of AK of the face and scalp [12]. 
Ameluz® is a nanoemulsion containing 8% ALA-HCl, with improved stability. In a 
recent study 82% of patients experienced pain during Ameluz® PDT but this was not 
significantly different to MAL PDT [11]. We developed a mouse model of PDT-
induced pain that enabled us to determine the molecular mechanisms involved. Use 
of the model in combination with an in vitro assay of PDT-induced excitation of 
nociceptive neurons led to our identification of menthol as a potential analgesic agent 
for minimising PDT-pain (see below). It is essential that we now determine whether 
the topical application of menthol is effective for PDT-induced pain relief in patients 
treated with PDT as this is a simple, safe approach that could easily be routinely 
incorporated into PDT regimes and if effective would markedly improve the 
management of such patients. Thus, this proposal describes the prospective 
randomised double blind, placebo controlled clinical trial we will undertake in which 
we investigate the use of topical menthol for PDT-induced pain relief in patients with 
AK of the face and scalp. 
 
Pain associated with PDT 
Most patients receiving PDT experience pain during irradiation. In Dundee, 16% of 
4717 PDT treatments were associated with severe pain [4]. This limits successful 
and effective delivery of PDT and negatively impacts on the patient’s experience of 
treatment. Unsurprisingly, given the nature of pain transmission, PDT is most painful 
in patients when performed on highly innervated skin such as the face and scalp [5, 
13]. Interestingly, higher pain levels are experienced during PDT for AK and psoriasis 
than for basal cell carcinoma [13, 14], perhaps implicating neuromodulatory factors 
released from specific cell types. Characteristics of irradiation (emission spectrum 
and irradiance) appear to influence the perception of pain. Red light produces more 
pain than violet light and pain appears to correlate with the rate of photobleaching of 
PpIX [15, 16]. Reduction of irradiance may reduce pain but greatly increases 
treatment times [6, 7]. Other options for pain relief are limited as conventional non-
invasive methods, such as topical analgesia with morphine or local anaesthetics are 
not significantly effective [5, 17, 18]. Local anaesthetic nerve block results in effective 
pain reduction [19] but is invasive, not feasible at all body sites and there may be risk 
of toxicity. Cooling is associated with slight reduction in PDT-induced pain [20], 
although there are concerns that this may reduce the efficacy of PDT [21]. 
 
 
 
Mechanisms of PDT pain 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 8 
 
 
Little is known about the mechanism(s) of PDT-induced pain. At the time of writing a 
literature search using the terms “pain and photodynamic therapy” yielded 423 
publications, although most relate to the prevalence of PDT-pain and the limited 
success of treatment. Inhibition of PDT-induced pain by nerve block [19] implicates 
classical modes of pain transmission in which voltage activated sodium channels 
(VASCs) are activated leading to action potentials in primary afferent fibres 
stimulating ascending pain pathways in the spinal cord, thalamus and cortex [22]. 
PDT pain is described as a burning sensation. Furthermore, demonstrations that 
cooling reduces PDT pain may implicate heat-sensitive nociceptors. The transient 
receptor potential (TRP) family of ion channels senses heat, among other noxious 
stimuli including the pungent vanilloid capsaicin [23].  
 
The heat/capsaicin activated TRP channel is TRPV1 [24] and this channel is a 
candidate for mediating PDT pain. However, PDT causes only modest temperature 
increases below the threshold for TRPV1 under normal conditions [24, 25] (Figure 1; 
Appendix 1) and thus there remains uncertainty about mechanisms involved. 
 
Pre-clinical Pilot Studies 
In pilot studies, we identified an electrophysiological correlate of PDT-evoked pain in 
cultured mouse primary afferent DRG neurons and developed a behavioural model 
for this phenomenon (Figures 2-9; Appendix 1). 
 
PpIX phototoxicity-induced pain behaviour in mice 
We examined the effect of laser irradiation (630 nm, 3.7 J/cm2) and ALA applied 
topically (4-6 h) to the tails of NIH SWISS mice. Neither topical ALA (n = 35), nor 
laser irradiation alone (n = 30), caused discernible pain behaviour in either mouse 
strain. By contrast, 20 ± 3 s (n = 30) of tail lifting, holding and licking occurred during 
60 s following laser irradiation of ALA treated tails (Figure 2a; Appendix 1). Pain 
behaviour ceased within 5 minutes suggesting that the underlying pain was acute 
and transient. Tail lifting, holding and licking did not occur in the 60 s period following 
irradiation in mice treated with vehicle cream. We observed PpIX emission non-
invasively using fluorescence spectroscopy with fibre-optic coupled laser excitation at 
405 nm (Figure 2b; Appendix 1). Compared to vehicle treated mouse tails, the 
characteristic PpIX emission spectrum was enhanced by ALA treatment to levels 
similar to those achieved in the ALA treated human forearm (Figure 2b; Appendix 1).  
The in vivo data demonstrated that neither PpIX production nor laser irradiation alone 
was sufficient to generate pain in mice. By contrast, ALA PDT was associated with 
quantifiable pain behaviour.  
 
PpIX phototoxicity evokes action potentials in DRG neurons  
Primary afferent dorsal root ganglion (DRG) neurons transmit nociceptive pain from 
peripheral sites, such as the tail, to the spinal cord. We dissociated DRG from mice 
and performed flow cytometry on cells grown for 7 days in vitro. Flow cytometry 
revealed that cells treated with ALA (1 mM for 4 h) produced PpIX fluorescence that 
was not seen in untreated cells (Figure 3a; Appendix 1). We examined responses of 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 9 
 
 
small DRG neurons (<25 µm) to ALA either alone or in combination with laser 
irradiation (630 nm) using the cell attached configuration to record action potentials. 
This approach preserves the intracellular milieu while action potentials are acquired 
as a combination of resistive and capacitive currents [26]. Spontaneous action 
potentials occurred very rarely in recordings from DRG neurons (grown for 1-15 days 
in vitro) under control conditions or in recordings from neurons exposed to ALA (1 
mM, 4-7 h)  prior to irradiation (Figure 3b; Appendix 1). By contrast, during laser 
irradiation (630 nm) neurons exposed to ALA exhibited bursts of frequent action 
potentials (Figure 3b; Appendix 1).  
 
While 97% of neurons responded to PpIX irradiation (day 4-15 in vitro), there was 
considerable variability in the latency to the first burst of action potentials (486 ± 20 s, 
n = 135), which equates to a mean light dose of 47 ± 2 J/cm2 required to evoke a 
response. The instantaneous frequency of action potentials was 11.6 ± 1.3 Hz (day 7 
in vitro). The mean frequency of firing during the entire period of irradiation was 0.23 
± 0.03 Hz. Interestingly, despite the known cellular toxicity of PpIX irradiation, 
resulting from the release of ROS, most DRG neurons survived the full 1200 s of 
laser exposure. 
 
Using the whole-cell current-clamp recording configuration we examined the effects 
on membrane potential of ALA and irradiation either alone or in combination (Figure 
3c; Appendix 1). DRG neurons exhibited infrequent spontaneous action potentials 
under control conditions.  Neither ALA (-57 ± 3 mV, n = 7) nor laser irradiation alone 
(-60 ± 3 mV, n = 5) affected resting membrane potential or frequency of spontaneous 
action potentials (Figure 3c; Appendix 9). However, laser irradiation of ALA treated 
(4-7 h) DRG neurons led to sustained depolarisation (of 9 ± 1 mV, n = 3) and the 
appearance of frequent action potentials (Figure 3d; Appendix 9). 
 
Taken together, the in vitro data demonstrate that neither PpIX production nor laser 
irradiation alone was sufficient to generate action potentials in nociceptive neurons. 
By contrast, PpIX irradiation depolarized neurons and initiated bursts of action 
potentials. 
 
Menthol suppresses PpIX phototoxicity-evoked action potentials and pain 
Menthol exhibits local anaesthetic effects through inhibition of VASCs on nociceptive 
neurons [27]. Menthol also causes a cooling sensation by activating TRPM8 
receptors [28]. Both of these actions could provide analgesia to patients being 
treated with PDT. We examined whether menthol (300 µM and 600 µM) inhibited 
ALA PDT-induced action potentials recorded from DRG neurons.  
 
Menthol inhibited action potential frequency in a concentration-dependent manner 
(Figure 4a; Appendix 1). Also, the percentage of cells that responded to PDT was 
reduced by menthol (600 µM) from 100% to 33%. Menthol (300 µM) had no effect on 
the threshold light dose; however, the reduction in the number of cells responding in 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 10 
 
 
the presence of 600 µM menthol precluded analysis of the average threshold light 
dose in this case.  
 
We next investigated whether menthol influenced ALA PDT-induced pain behaviour 
in mice. The application of menthol (16%) in aqueous cream had no effect on PpIX-
mediated fluorescence determined using the photospectrometer with fibre-optic 
coupled laser excitation at 405nm (Figure 4b; Appendix 1). The application of 
menthol (2% and 16%) to the tails of mice 600s prior to laser (630 nm, 3.7 J/cm2) 
irradiation caused a dose-dependent reduction in the duration of pain behaviour 
(Figure 4c; Appendix 1). These data suggest a role for TRP pathways [29] and 
indicate that menthol is an effective analgesic for treating ALA PDT-induced pain in 
mice and we will now investigate this in patients receiving PDT for AK. 
 
1.2 
RATIONALE FOR STUDY 
As menthol is such a well-tolerated and safe treatment we would envisage that if the 
clinical study supported the ex-vivo findings and did indeed significantly reduce PDT-
induced pain, then this would be routinely incorporated into PDT treatment protocols 
and significantly improve patient care and the tolerance of PDT. We will use 5% 
menthol as this is available for clinical use and in order not to miss a potential pain-
relieving effect. 
 
2 
STUDY OBJECTIVES 
2.1 
OBJECTIVES 
2.1.1 Primary Objectives 
The primary objective of this study is to examine whether the pain (as assessed by 
VAS pain scores) of topical PDT is significantly different when using menthol in 
aqueous cream applied before PDT compared with aqueous cream (placebo) 
application before PDT. 
 
2.1.2 Secondary Objectives 
We will also examine possible differences in phototoxicity of the two regimens and 
assess patient evaluation of treatment. We will additionally assess fluorescence after 
cream application and before irradiation, using Wood’s light as used in routine clinical 
practice. Efficacy of the two treatment regimens will also be assessed. 
 
2.2 
OUTCOMES 
2.2.1 Primary Outcomes 
Pain will be assessed by the patient using a visual analogue scale of 0-10 cm. 
Maximal recall of pain experienced during PDT will be recorded immediately after 
PDT, and then pain scores at three, six and 24 hours after PDT. The patient-scored 
pain at the first time point will be undertaken with the aid of a blinded investigator and 
subsequently the patient alone will assess symptoms. 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 11 
 
 
2.2.2.    Secondary Outcomes 
Phototoxicity as assessed by semi-quantitative scoring of erythema, oedema and  
urticaria will be assessed immediately after irradiation.  Fluorescence will also be 
assessed after Ameluz and IMP applications using Wood’s light. Efficacy of treatment 
(clearance, partial or no response) three months after PDT will be determined 
clinically. Patient evaluation of treatment will also be assessed. 
 
3 
STUDY DESIGN 
3.1 
STUDY DESCRIPTION 
This protocol describes a prospective, single site, randomised, double blind placebo 
controlled study to assess the efficacy of menthol in aqueous cream for PDT-induced 
pain. Each subject will act as their own control. Potential participants with a diagnosis 
of actinic keratosis (AK) bilaterally affecting face or scalp who are referred for PDT 
will be identified by the Chief Investigator (CI), a consultant dermatologist, screening 
referrals and will be invited to participate by letter and a patient information sheet 
(PIS) will be sent out with the PDT clinic appointment details. Patients will also be 
identified in the dermatology outpatient or PDT clinics by either a dermatologist, 
specialist nurse or technologist and will be provided with details of the study and a 
PIS. At first visit at the PDT clinic the study will be described in full detail by a PDT 
study doctor, technologist or clinic nurse and written informed consent will be 
obtained 
prior 
to 
any 
study-related 
activities. 
Computer-generated 
block 
randomisation of the active/placebo to right or left sides and which side will be 
treated first will be undertaken by Tayside Pharmaceuticals. Patients will then receive 
their randomised treatment and this will also be undertaken by the Photobiology 
Technician or nurse as is the normal clinical practice in the PDT Unit.   
 
A study clinician, technologist or nurse will obtain a medical history and the areas for 
treatment will be examined, the study fields will be marked out, lesions counted and 
the fields mapped and photographed. The maximal diameter of each comparable 
field will be 5x10cm. Topical PDT will be undertaken using the standard Ameluz® 
PDT regime (11). In brief, any hyperkeratotic areas will be surface prepared using a 
disposable ring curette (Stiefel™), without the need for local anaesthesia. Ameluz® 
gel will be thinly applied to both comparative fields, left to dry and occluded for three 
hours with Tegaderm and Mepore dressings. After removal of the dressings and 
surplus gel, the active treatment (menthol 5% in aqueous cream) or placebo 
(aqueous cream) will be applied to right/left side according to randomisation The 
IMPD/placebo will be provided as 1g in 2mL syringes, applied to the maximum field 
size field of 5x10cm or pro-rata to smaller field sizes. Ten minutes later any excess 
cream will be wiped off and irradiation will commence (LED 37.5 J/cm2, irradiance 
approximately 80 mW/cm2), with the randomisation to account for which side will be 
treated first. Menthol vapour will be in the room in order to mask the vapour of the 
IMP and to aid with ensuring blinding of both patient and assessor (research nurse or 
another technologist). 
 
Assessments 
Fluorescence will be examined using a semi-quantitative scoring system (0=none; 
1=minimal; 2=moderate; 3=strong) after 3 h of Ameluz application and after 
menthol/placebo application. 
 
Pain scores will be recorded by the patient immediately after irradiation (as recall of 
maximal pain experienced during irradiation) and at 3, 6 and 24 h after irradiation 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 12 
 
 
using a VAS score of 0-10cm at each time-point. The study technologist  or research 
nurse will be present at the time of the first pain score but patients will fill in the VAS 
scores themselves at home for the 3, 6 and 24 h time-points and send these back to 
the PDT clinic by stamped addressed envelope. A study nurse will contact the patient 
by phone at one week, to ask about any adverse effects and to check that the VAS 
scores are returned. 
 
Phototoxicity will be assessed by the study technologist or research nurse 
immediately after irradiation using a semi-quantitative scoring system for erythema 
(0=none; 1=mild; 2=moderate; 3=severe), oedema (1=yes; 0=no), exudation (1=yes; 
0=no) and urticaria (1=yes; 0=no). 
 
Efficacy will be assessed clinically approximately three months (± 2 weeks) after 
PDT, with clearance, partial response or no response recorded as outcomes. Patient 
evaluation of treatment and of blinding will also be assessed for each treatment site 
when the patient returns their pain scores after 24h, using the following two 
questions: [1] Which side do you think received menthol? Right/left/not sure; [2] 
Which side do you think was best? Right/left/no difference.  
 
 
3.2 
TRIAL FLOWCHART 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Recruit
t
Randomisation by 
Technologist/nurse to receive 
IMP/placebo application by unblinded 
technologist/nurse who will be delivering 
PDT treatment (menthol vapour in air to 
Unblinded 
t
h
l
i t/
d li
Technologist/nurse 
A
l
®
Immediately after irradiation patient 
self-rated pain score (VAS 0 – 10) 
Pain assessment record (VAS 
scores) completed by patient 
at 3 hours, 6 hours and 24 
h
ft
PDT P ti
t
Follow up 
telephone call by 
Technologist/nurse applies Ameluz® 
cream to treatment areas for 3 h as

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 13 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3.3 
STUDY MATRIX  
ACTIVITY 
Day 1 
Day 2 
DAY 
8 
Approx.  
3 months 
Informed consent 
√ 
 
 
 
Eligibility screening 
√ 
 
 
 
Standard skin preparation for PDT 
√ 
 
 
 
Application of IMP/placebo (remove after 
10 minutes) 
√ 
 
 
 
PDT irradiation 
√ 
 
 
 
Pain assessment (visual analogue scores) 
by subject immediately after PDT - clinic 
√ 
 
 
 
Fluorescence assessment by technician 
√ 
 
 
 
Phototoxicity assessment by technician 
√ 
 
 
 
Pain assessment (visual analogue scores) 
by subject 3hrs after PDT - home 
√ 
 
 
 
Pain assessment (visual analogue scores) 
by subject 6 hrs after PDT - home 
√ 
 
 
 
Pain assessment (visual analogue scores) 
by subject 24 hrs after PDT - home 
 
√ 
 
 
Follow-up phone call by research nurse  
 
 
√ 
 
Assessment of treatment efficacy at 3 
months after PDT 
 
 
 
√ 
Patient evaluation of PDT & blinding 
 
√ 
 
 
 
 
4 
STUDY POPULATION 
4.1 
NUMBER OF PARTICIPANTS 
30 patients will be recruited to the study, with a view to 21 completing the study 
allowing for a 30% drop-out rate at the three month follow-up visit. The study will be 
performed in one centre and each participant will be in the study for three months.  
 
Assessment of 
treatment efficacy at 
Data and statistical
Report
Archiving of 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 14 
 
 
4.2 
INCLUSION CRITERIA 
A subject will be eligible for inclusion in this study only if all of the following criteria 
apply: 
1. Adults >18 years. Target population is men or women ≥50 years (only post-
menopausal women) 
2. Presence of actinic keratoses (AK) on the face and scalp involving both right and 
    left comparable sites. 
3. Free of significant physical abnormalities (e.g. tattoos, dermatoses) in the potential 
    treatment area that may cause difficulty with examination or final evaluation. 
4. Able to understand and adhere to protocol requirements. 
 
4.3 
EXCLUSION CRITERIA 
1. Unable to give written informed consent. 
2. Allergy to menthol, aqueous cream or excipients 
3. Participation in a drug trial or other interventional study within 30 days of 
    recruitment to this study 
4. Pre-menopausal women, pregnancy, breast feeding, planning to conceive 
5. Chronic pain 
 
5 
PARTICIPANT SELECTION AND ENROLMENT 
 
5.1 
IDENTIFYING PARTICIPANTS 
Potential participants with a diagnosis of actinic keratosis (AK) who are referred for 
PDT will be identified by the chief investigator (CI), a consultant dermatologist via 
screening referrals and will be invited to participate by letter and a patient information 
sheet (PIS) will be sent out with the PDT clinic appointment details. Potential 
participants will also be identified during consultation by a Dermatologist, Specialist 
Nurse or technologist in the Dermatology or PDT clinics.  Patients will be invited to 
participate in the study and will be given a Participant Information Sheet (PIS), which 
will include contact details for members of the research team. In the event of the 
patient not receiving the study PIS in the clinic, one will be sent with their 
appointment letter for the PDT clinic. All subjects will be given at least 24 hours to 
read the PIS and have the opportunity to discuss the study and have any questions 
answered before deciding if they wish to participate in the study. If willing to proceed, 
written informed consent will be obtained by a Dermatologist or a delegated suitably 
qualified member of the research team. 
 
5.2 
CONSENTING PARTICIPANTS 
Where a participant requests to speak with a Dermatologist from the study team the 
consent process will not be completed until the participant has spoken to the doctor 
and had all their questions answered to their satisfaction. 
 
5.3 
SCREENING FOR ELIGIBILITY 
Potential participants with a diagnosis of actinic keratosis (AK) bilaterally affecting 
face or scalp who are referred for PDT will be identified by the Chief Investigator (CI), 
a consultant dermatologist, screening referrals and will be invited to participate by 
letter and a patient information sheet (PIS) will be sent out with the PDT clinic 
appointment details. Patients will also be identified in the dermatology outpatient or 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 15 
 
 
PDT clinics by either a dermatologist, specialist nurse or technologist and will be 
provided with details of the study and a PIS. At first visit at the PDT clinic the study 
will be described in full detail by a PDT study doctor, technologist or clinic nurse and 
written informed consent will be obtained prior to any study-related activities. 
 
5.4 
INELIGIBLE AND NON-RECRUITED PARTICIPANTS 
A screening log will be populated and maintained to list reasons for ineligibility and 
non-recruitment. These patients will then proceed to standard clinical care 
 
5.5 
RANDOMISATION 
5.5.1 Randomisation 
Randomisation will be to left or right side within each individual as we cannot 
consider pain experiences on right vs. left within an individual as being independent. 
We want to compare pain immediately after PDT illumination (time-point of most 
interest) and, as another way of comparing between the interventions "pain 
experience over-time" (while trying to reduce the multiple comparisons "problem”), to 
compare within-subjects Areas Under the Curve of pain over time. 
 
Patients will be randomly allocated to either active or placebo treatment to right or left 
side using a computer-generated block randomisation sequence, which will also 
include randomisation as to which side will be treated first. The randomisation code 
will be generated by Tayside Pharmaceuticals and will be concealed from study 
investigators.  
 
5.5.2 Treatment Allocation 
Patients will be allocated treatment to both right side and left side e.g. right side to 
receive treatment A; left side to receive treatment B. Patients should be unable to 
distinguish treatments by smell as menthol has a strong smell, which will likely 
permeate the air around the patient. In addition, menthol vapour will be present in the 
room so that there is an overall menthol smell, which will be difficult to localise. 
 
5.5.3 Blinding and Emergency Unblinding Procedures 
Those assessing patients (Consultant Dermatologist, study technologist or research 
nurse) will not be aware of which side has received which intervention. It is possible 
that all patients (from sensation [cooling] of menthol) might not remain fully blinded. 
Patients will be instructed not to tell those assessing them if they suspect they know 
which intervention is applied to each side. After treatment, patients will be asked to 
provide an opinion as to which treatment was applied to each side to allow 
assessment as to how complete patient blinding was. 
Given the nature of the study, it is very unlikely that unblinding will be required. If 
required, it will be conducted by a PBU member of staff unconnected to the trial. 
 
 
5.5.4 Withdrawal procedures 
Although a participant is not obliged to give reason(s) for withdrawing prematurely, if 
the participant appears lost to follow up, the CI will make a reasonable effort to 
ascertain the reason(s), while fully respecting the individual’s rights, and will 
demonstrate that everything possible was done in an attempt to find any participant 
lost to follow-up. Those lost to follow-up or withdrawn will be identified and a 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 16 
 
 
descriptive analysis of them provided, including the reasons for their loss and its 
relationship to treatment and outcome. 
 
6 
INVESTIGATIONAL MEDICINAL PRODUCT  
6.1 
STUDY DRUGS/IMPS 
6.1.1 Study drug identification 
 
Active IMP is formulated into a cream and supplied as 1g in a 2ml syringe for topical 
administration.  
 
Composition of Active IMP - Levomenthol 5% Cream 
Component 
Reference 
Amount 
Menthol 
Ph Eur 
50mg (5% w/w) 
Aqueous Cream 
BP 
PL 04917/0057 
to 1g 
(50mg menthol + 950mg 
aqueous cream) 
 
Placebo is provided as a cream (1g in a 2ml syringe) for topical administration.  
 
Composition of placebo cream - Aqueous Cream BP. 
Component 
Reference 
Amount 
Aqueous Cream  
BP 
PL 04917/0057 
1g (100%) 
 
6.1.2 Study IMP Manufacturer 
 
The investigational drug substance is Menthol 5% in Aqueous Cream. This product is 
manufactured by Tayside Pharmaceuticals, Ninewells Hospital & Medical School, 
Dundee, DD1 9SY, MIA (IMP) 14076 (see IMPD). 
 
The placebo is Aqueous Cream BP, which is a licensed product, PL 04917/0057 
 
6.1.3 Marketing authorisation holder 
Tayside Pharmaceuticals MIA (IMP) 14076 
 
6.1.4 Labelling and Packaging 
Study IMPs will be packaged and labelled by Tayside Pharmceuticals. 
 
6.1.5 Storage 
Study IMPs will be released by Tayside Pharmceuticals to NHS Tayside Pharmacy 
who will supply them to the PBU. IMPs will be stored in a local PBU storage area 
which will be audited prior to use by the NHS Tayside Clinical Trials Pharmacist. 
Temperature control logs will be maintained.  
 
6.1.6 IMP Safety Information 
The simplified IMPD will be held in the Pharmacy Site File (PSF) and in the Trial 
Master File (TMF). No adverse effects are expected. A minor cooling or tingling 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 17 
 
 
sensation may be expected with IMP contact with skin. Contact with eyes or mucosal 
surfaces will be avoided as these are not within the study treatment sites. 
 
6.1.7 Accountability procedures  
An IMP Accountability Log will be maintained in the TMF. 
 
6.3 
DOSING REGIME 
IMP will be applied topically by a study technologist or nurse at study Visit 1. After 
removal of the dressings and surplus Ameluz® gel, the active treatment (menthol 5% 
in aqueous cream) or placebo (aqueous cream) will be applied to right/left side 
according to randomisation. Ten minutes later any excess cream will be wiped off 
and irradiation will commence using a standard red light LED (37.5 J/cm2, irradiance 
80 mW/cm2), with the randomisation to account for which side will be treated first. 
Menthol vapour will be in the room in order to mask the vapour of the IMP and to aid 
with ensuring blinding of both patient and assessor (research nurse or another 
technologist). 
 
6.4 
DOSE CHANGES 
No planned dose changes in IMPs 
 
6.5 
PARTICIPANT COMPLIANCE 
As both IMPs will be applied topically by a study technologist at study Visit 1, there 
will be no requirement to monitor participant compliance as this will not be relevant. 
 
6.6 
OVERDOSE 
No risk of overdose 
 
6.7 OTHER MEDICATIONS 
6.7.1 Permitted medications 
Usual medications are permitted except for menthol preparations used on the 
treatment day. 
6.7.2 Prohibited medications 
Menthol preparations used on the treatment day 
6.7.3 Concomitant Medications  
All usual medications will be permitted except for menthol preparations. Concomitant 
medications will be logged in the Case Report Form (CRF). 
7 
STUDY ASSESSMENTS 
7.1 
STUDY ASSESSMENTS 
As detailed above – pain, fluorescence, phototoxicity, efficacy and patient evaluation 
will be assessed. 
 
7.2 
SAFETY ASSESSMENTS 
Pain and phototoxicity will be assessed by per protocol and intention to treat 
analyses 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 18 
 
 
 
8 
DATA COLLECTION & MANAGEMENT 
8.1 
DATA COLLECTION 
Data will be collected in the CRF and appropriate clinical information will also be 
recorded in patient notes.  Both patient notes and CRF will act as source data. 
 
8.2 
DATA MANAGEMENT SYSTEM  
The data management system will be Excel. The study system will be based on the 
protocol and CRF. The CRF will not collect more information than is required to meet 
the aims of the study and to ensure the eligibility and safety of the participant.  Data 
collection and validation will be carried out as described in TASC SOP on Excel in 
CTIMPs. 
 
9 
STATISTICS AND DATA ANALYSIS 
9.1 
SAMPLE SIZE CALCULATION 
We were not able to obtain variance for within-subjects pain differences from similar 
studies. An assessment of pain experience with PDT in our unit found a standard 
deviation of between subjects VAS pain score of 2.7cm. Rounding this up to 3cm and 
conservatively estimating that within-subject’s pain score SD will be two-thirds of this 
(2cm) then we estimated that 21 subjects should give us 90% power to detect a 
mean difference in VAS scores of 1.5 cm as significant at the 5% level. To allow for 
dropouts, assuming dropout rate by 3 months of up to 30%, we will recruit 30 
subjects. 
 
9.2 
PROPOSED ANALYSES 
The main analysis will the difference between within-subject pain using appropriate 
paired methods (paired Student’s t-test if assumptions met). The difference will be 
expressed with 95% confidence interval. VAS scores immediately after PDT and the 
areas under the curve for pain scores plotted over each of the time points will be 
assessed. Within subject comparisons of fluorescence, phototoxicity, efficacy and 
patient evaluation will be secondary outcome measures, using paired statistical 
analyses. 
 
Amendment 
Since the original concept and set up of the study, there have been changes in the 
practice of PDT for AKs on the face and scalp, with low illuminance daylight PDT now 
favoured when practicable because this form of PDT is less painful than conventional 
PDT.  Therefore, we will perform (statistical analysis by someone not involved in 
patient treatments and assessments, to ensure blinding) an interim analysis.  With 
the same assumptions as before with a power of 90% we expect to detect a 
difference (at alpha = 0.1 level, two tailed testing) of 3 cm or more (on VAS) in pain 
between groups with 9 subjects should such a difference exist.  We will therefore 
recruit a minimum of 9 participants and if on this interim analysis such a difference is 
detected then the study will be continued as originally planned in order to determine 
whether the difference can be detected at alpha = 0.05 level of significance, unless 
the dermatologist analysing the data advises stopping early as a greater difference 
already detected.  If it seems unlikely that there will be a difference of ≥ 3 cm in pain 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 19 
 
 
on VAS based on this interim analysis, then (with the changes in use of PDT for AKs 
on face and scalp) the data analyst will advise stopping the study. 
 
 
10 ADVERSE EVENTS 
 
10.1 DEFINITIONS 
An adverse event (AE) is any untoward medical event affecting a clinical trial 
participant. Each initial AE will be considered for severity, causality or expectedness 
and may be reclassified as a serious event or reaction based on prevailing 
circumstances. 
An adverse reaction (AR) is where it is suspected that an AE has been caused by a 
reaction to a trial drug 
A serious adverse event (SAE), serious adverse reaction (SAR) or suspected 
unexpected serious adverse reaction (SUSAR) is any AE, AR or UAR that at any 
dose: 
 
• 
results in death 
• 
is life threatening  
• 
requires hospitalisation or prolongation of existing hospitalisation 
• 
results in persistent or significant disability or incapacity 
• 
is a congenital anomaly or birth defect 
• 
Or is otherwise considered serious 
Note: 
Hospitalisations 
for 
treatment 
planned 
prior to 
randomisation 
and 
hospitalisation for elective treatment of a pre-existing condition will not be considered 
as an SAE. However any adverse events occurring during such hospitalisation will be 
recorded. 
 
10.2 RECORDING AND REPORTING AES AND SAES 
Topical menthol may cause a sensation of cooling and hyperalgesia and, with 
repeated applications may cause some skin irritation. However, with a single 10 
minute application to a small area, as proposed in this study, we do not anticipate 
any adverse effects and, indeed, any cooling, hyperalgesic effect may be desirable 
with respect to potential pain relief. The clinical data and Reference Safety 
Information (RSI) are summarised in Appendix 2.  
All AEs and SAEs will be recorded from the time a participant consents to join the 
study until the last study visit. Participants with unresolved AEs at the last study visit 
will be followed up until resolution or 30 days after last patient, last visit (LPLV), 
whichever is sooner. SUSARS will be followed until resolution.  
The CI or delegate will ask about the occurrence of AEs and hospitalisations at every 
visit during the study. AEs will be recorded on the AE Log in the CRF. SAEs will be 
submitted 
on 
an 
SAE 
form 
to 
the 
TASC 
Safety 
Section 
(pharmacovigilance.tayside@nhs.net) within 24 hours of becoming aware of the 
SAE. SAEs will be assessed for expectedness and causality by the Investigator. The 
evaluation of expectedness will be made based on the knowledge of the reaction and 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 20 
 
 
the relevant product information (simplified IB; Appendix 2). Refer to TASC SOP 
11 “Identifying, Recording and Reporting Adverse Events for CTIMPs”. 
 
10.3 REGULATORY REPORTING REQUIREMENTS 
 
The Sponsor, together with the CI, is responsible for reporting SUSARs to the 
competent authority, the MHRA, the Research Ethics Committee (REC) and any 
other competent authorities. Fatal or life threatening SUSARs will be reported within 
7 days and non-fatal and non-life threatening SUSARs within 15 days. 
 
 
10.4 ANNUAL REPORTING REQUIREMENTS 
The following reports will be submitted each year as a condition of the authorisation 
to undertake a clinical trial or as a condition of a favourable opinion from a REC. 
  
The Development Safety Update Report (DSUR) will be prepared jointly by the TASC 
Safety Section and CI and submitted to the MHRA on the anniversary of date of 
Clinical Trial Authorisation (CTA). 
 
An NRES CTIMP Safety Report Form will be sent to REC along with the DSUR. 
Reports of SUSARs in the UK, urgent safety measures and any other safety reports 
submitted, for example, reports of a data monitoring committee, will also be 
accompanied by a Safety Report Form.  
 
A NRES Annual Progress Report for CTIMPs will be prepared and submitted by the 
CI to REC, and copied to Sponsor, on the anniversary date of the REC favourable 
opinion. 
 
10.5 URGENT SAFETY MEASURES 
The CI or other clinician may take appropriate immediate urgent safety measures in 
order to protect the participants of a CTIMP against any immediate hazard to their 
health or safety. The MHRA, REC and Sponsor will be notified in writing within three 
days. 
 
11 PREGNANCY 
Pregnancy is not considered an AE or SAE, unless there is a congenital abnormality 
or birth defect. Any unexpected pregnancy occurring during the clinical study and the 
outcome of the pregnancy, will be recorded on a TASC Pregnancy Notification Form 
and submitted to the TASC Safety Section (pharmacovigilance.tayside@nhs.net) 
within 24 hours of becoming aware of the pregnancy. The pregnancy will be followed 
up until the end of the pregnancy. If the study participant is a male, informed consent 
for follow up must be sought and obtained from his female partner. This study will 
only be undertaken in women who are >50 years old and post-menopausal. 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 21 
 
 
12 TRIAL MANAGEMENT AND OVERSIGHT ARRANGEMENTS 
12.1 TRIAL MANAGEMENT GROUP 
The trial will be co-ordinated by a Trial Management Group, consisting of the CI, Trial 
Technologist and research nurse who will meet on a weekly basis. The TMG will also 
be responsible for oversight of data monitoring. 
 
12.2 TRIAL MANAGEMENT 
A Research Nurse will oversee the study and will be accountable to the CI. The 
Research Nurse will be responsible for checking the CRFs for completeness, 
plausibility and consistency. However, this will remain the overall responsibility of the 
CI. Any queries will be resolved by the CI or delegated member of the trial team.  
A study-specific Delegation of Responsibilities & Signature Log will be prepared, 
detailing the responsibilities of each member of staff working on the trial.  
 
12.3 INSPECTION OF RECORDS 
The CI and the institutions involved in the study will permit trial related monitoring, 
audits, REC review, and regulatory inspection(s). In the event of an audit, the CI will 
allow the Sponsor, representatives of the Sponsor or regulatory authorities direct 
access to all study records and source documentation. 
 
12.4 RISK ASSESSMENT 
A study risk assessment was carried out by the TASC Research Governance 
Manager prior to Sponsorship approval being granted. 
 
12.5 STUDY MONITORING 
The Sponsor has determined the appropriate extent and nature of monitoring for the 
trial and will appoint appropriately qualified and trained monitors. Thus, any potential 
risks will be minimized, 
 
13 GOOD CLINICAL PRACTICE 
13.1 ETHICAL CONDUCT OF THE STUDY 
The study will be conducted in accordance with the principles of good clinical practice 
(GCP). In addition to Sponsorship approval, a favorable ethical opinion will be 
obtained from an appropriate REC. Authorisation from an appropriate competent 
authority(s) and appropriate NHS R&D permissions(s) will be obtained prior to 
commencement of the study. 
 
13.1.1 Confidentiality 
All laboratory specimens, evaluation forms, reports, and other records will be 
identified in a manner designed to maintain participant confidentiality. All records will 
be kept in a secure storage area with limited access to study staff only. Clinical 
information will not be released without the written permission of the participant, 
except as necessary for monitoring and auditing by the Sponsor, its designee or 
Regulatory Authorities. The CI and study staff involved with this study will not 
disclose or use for any purpose other than performance of the study, any data, 
record, or other unpublished, confidential information disclosed to those individuals 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 22 
 
 
for the purpose of the study. Prior written agreement from the Sponsor or its 
designee will be obtained for the disclosure of any said confidential information to 
other parties. 
 
13.1.2 Data Protection 
The CI and study staff involved with this study will comply with the requirements of 
the Data Protection Act 1998 with regard to the collection, storage, processing and 
disclosure of personal information and will uphold the Act’s core principles. The CI 
and study staff will also adhere, if appropriate, to the current version of the NHS 
Scotland Code of Practice on Protecting Patient Confidentiality.  Access to collated 
participant data will be restricted to the CI and appropriate study staff. 
Computers used to collate the data will have limited access measures via user 
names and passwords. 
Published results will not contain any personal data that could allow identification of 
individual participants. 
 
13.1.3 Insurance and Indemnity 
The University of Dundee and Tayside Health Board are Co-Sponsoring the study. 
Insurance. – The University of Dundee will obtain and hold Professional Negligence 
Clinical Trials Insurance cover for legal liabilities arising from the study. 
Tayside Health Board will maintain its membership of the Clinical Negligence and 
Other Risks Insurance Scheme (“CNORIS”) which covers the legal liability of Tayside 
in relation to the study]. 
Where the study involves University of Dundee staff undertaking clinical research on 
NHS patients, such staff will hold honorary contracts with Tayside Health Board 
meaning they will have cover under Tayside’s membership of the CNORIS scheme. 
Indemnity.The Co-Sponsors do not provide study participants with indemnity in 
relation to participation in the Study but have insurance for legal liability as described 
above. 
 
14 STUDY CONDUCT RESPONSIBILITIES 
14.1 PROTOCOL AMENDMENTS 
The CI will seek Sponsor approval for any amendments to the Protocol or other study 
documents. Amendments to the protocol or other study docs will not be implemented 
without approval from the Sponsor and subsequent approval from the appropriate 
REC and/or Regulatory Authority, as appropriate, and NHS R&D Office. Refer to 
TASC SOP 26 “Amendments to CTIMPs” 
 
14.2 PROTOCOL DEVIATIONS, BREACHES AND WAIVERS 
The CI will not implement any deviation from the protocol without agreement from the 
Sponsor, except where necessary to eliminate immediate hazard to trial participants. 
In the event that the CI needs to deviate from the protocol, the nature of and reasons 
for the deviation will be recorded in the CRF, documented in a TASC Deviation & 
Breach Log and notified to the Sponsor. If this necessitates a subsequent protocol 
amendment, this will be submitted to the Sponsor for approval and then to the 
appropriate REC, Regulatory Authority and local NHS R&D for review and approvals 
as appropriate. It is Sponsor policy that waivers to the Protocol will not be approved. 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 23 
 
 
In the event that a serious breach of the protocol or GCP is suspected, this will be 
reported to the Sponsor immediately using the form “Notification to Sponsor of 
Potential Serious Breach or Serious Deviation”. Refer to TASC SOP 25 “Escalation 
and Notification of Serious Breaches of GCP or the Trial Protocol for CTIMPs”.  
 
14.3 STUDY RECORD RETENTION 
Archiving of study documents will be carried out as specified in TASC SOP 13: 
Archiving Clinical Research Data for Clinical Trials of Investigational Medicinal 
Products. For studies where the data does not form part of an application for a 
Marketing Authorisation (MA) all study documentation will be kept for at least 5 years. 
For studies where the data does form part of an application for a Marketing 
Authorisation (MA) all study documentation will be kept for at least 15 years. 
 
14.4 END OF STUDY 
The end of study is defined as last patient last visit (LPLV). The Sponsor and CI have 
the right at any time to terminate the study for clinical or administrative reasons. The 
end of the study will be reported to the Sponsor, REC, Regulatory Authority and NHS 
R&D Office within 90 days, or 15 days if the study is terminated prematurely. The CI 
will ensure that any appropriate follow up is arranged for all participants. A final report 
of the study will be provided to the Sponsor, REC and Regulatory Authority within 
1 year of the end of the study. 
 
14.5 CONTINUATION OF DRUG AT END OF STUDY 
Not applicable 
 
15 REPORTING, PUBLICATIONS AND NOTIFICATION OF RESULTS 
15.1 AUTHORSHIP POLICY 
Ownership of the data arising from this study resides with the study team and their 
respective employers. On completion of the study, the study data will be analysed 
and tabulated, and a clinical study report will be prepared.  
 
15.2 PUBLICATION AND 15.3 PEER REVIEW 
The evaluated data will be used for peer-reviewed publication and presentation at 
scientific meetings. Trial investigators may present orally and publish in writing study 
results. A study summary will also be made available to Investigators for 
dissemination within their clinical areas (where appropriate and at their discretion). 
 
 
16 
REFERENCES 
1. Morton CA et al., European Guidelines for topical PDT: Part 1. J Eur Acad 
Dermatol Venereol 2013; 27: 536-44 
2. Morton CA et al., European guidelines for topical PDT: Part 2. J Eur Acad 
Dermatol Venereol 2013; 27: 672-9 
3. Morton CA et al., Guidelines for topical PDT. Br J Dermatol 2008; 159:1245-66 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 24 
 
 
4. Attili SK et al., A review of pain experienced during topical PDT- our experience in 
Dundee. Photodiagnosis Photodyn Ther 2011; 8: 53-7 
5. Warren CB, et al. Pain associated with aminolevulinic acid-PDT of skin disease. J 
Am Acad Dermatol 2009; 61: 1033-43 
6. Wiegell SR et al., Continuous activation of PpIX by daylight is as effective and 
less painful than conventional PDT for actinic keratoses: a randomised controlled 
single-blinded study. Br J Dermatol 2008, 158: 740-6 
7. Moseley H et al., An open pilot study of ambulatory PDT using a wearable low-
Irradiance organic LED light source in the treatment of non-melanoma skin 
cancer. Br J Dermatol 2009; 161: 170-3 
8. Gholam P et al., Treatment with 5-aminolaevulinic acid methylester is less painful 
than treatment with 5-aminolaevulinic acid nanoemulsion in topical PDT for 
actinic keratosis. Dermatology 2011; 222: 358-62 
9. Moloney FJ & Collins P. Randomized double-blind prospective study to compare 
5-aminolaevulinic acid methylester with 5-ALA PDT for extensive scalp actinic 
keratosis. Br J Dermatol 2007; 157: 87-91 
10. Valentine RM et al. A quantitative comparison of 5-aminolaevulinic acid- and 
methyl aminolevulinate-induced fluorescence photobleaching and pain during 
PDT. Photochem Photobiol 2011; 87: 242-9 
11. Dirschka T et al. PDT with BF-200 ALA for the treatment of actinic keratosis: 
results of a multicentre randomized observer-blind phase III study in comparison 
with a registered methyl-5-aminolaevulinate cream and placebo. Br J Dermatol 
2012; 166:137-46 
12. Tzogani K et al., The European Medicines Agency approval of 5-ALA (Ameluz) 
for the treatment of actinic keratosis of mild to moderate intensity on the face and 
scalp. J Dermatolog Treat. 2014; 25: 371-4 
13. Grapengiesser S et al., Pain caused by PDT of skin cancer. Clin Exp Dermatol 
2002; 27: 493-7 
14. Radakovic-Fijan S et al., Topical aminolaevulinic acid-based PDT as a treatment 
option for psoriasis? Results of a randomized observer-blinded study. Br J 
Dermatol 2005; 152: 279-83 
15. Cottrell WJ et al., Irradiance-dependent photobleaching and pain in delta-
Aminolevulinic acid-PDT of superficial basal cell carcinomas. Clin Cancer Res 
2008; 14: 4475-83 
16. Mikolajewska P et al., Topical aminolaevulinic acid- and aminolaevulinic acid 
methyl ester-based PDT with red and violet light: influence of wavelength on pain 
and erythema. Br J Dermatol 2009, 161: 1173-9 
17. Holmes MV et al., A randomized double-blind placebo-controlled study of the 
efficacy of tetracaine gel (Ametop®) for pain relief during topical PDT. Br J 
Dermatol 2004; 150: 337-40 
18. Langan SM & Collins P. Randomized double-blind placebo-controlled prospective 
study of the efficacy of topical anaesthesia with a eutectic mixture of lignocaine 
2.5% and prilocaine 2.5% for topical 5-aminolaevulinic acid-PDT for extensive 
scalp actinic keratoses. Br J Dermatol 2006; 154: 146-9 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 25 
 
 
19. Paoli J et al., Nerve blocks provide effective pain relief during topical PDT for 
extensive facial actinic keratoses. Clin Exp Dermatol 2008; 33: 559-64 
20. Pagliaro J et al., Cold air analgesia in PDT of basal cell carcinomas and Bowen’s 
disease: An effective addition to treatment. Dermatol Surg 2004;30: 63-6 
21. von Felbert V et al., PDT of multiple actinic keratosis: reduced pain through use 
of visible light plus water-filtered infrared A compared with light from light-emitting 
diodes. Br J Dermatol 2010; 163: 607-15 
22. Mogil J.S. Animal models of pain: progress and challenges. Nat Rev Neurosci 
2009; 10: 283-94 
23. Patapoutian A et al., Transient receptor potential channels: targeting pain at the 
source. Nat Rev Drug Discov 2009; 8: 55-68 
24. Caterina MJ et al., The capsaicin receptor: a heat-activated ion channel in the 
pain pathway. Nature 1997; 389: 816-24 
25. Palsson S et al., Kinetics of the superficial perfusion and temperature in 
connection with PDT of basal cell carcinomas using esterified and non-esterified 
5-aminolaevulinic acid. British Journal of Dermatology 2003; 148: 1179-1188 
26. Hales TG et al., GABA has excitatory actions on GnRH-secreting immortalized 
hypothalamic (GT1-7) neurons. Neuroendocrinology 1994; 59: 297-308 
27. Pan R et al., Central mechanisms of menthol-induced analgesia. J Pharmacol 
Exp Ther 2012; 343:661-672 
28. Liu B et al., TRPM8 is the principal mediator of menthol-induced analgesia of 
acute and inflammatory pain. Pain 2013; 154:2169-217 
29. Babes A et al., Photosensitization in porphyrias and photodynamic therapy 
involves TRPA1 and TRPV1. J Neuroscience 2016; 36: 5264-78 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 26 
 
 
Appendix 1 
Figures 
 
Figure 1. Temperature increase caused by laser irradiation of A, the in vitro 
recording chamber and B, a mouse tail (see text). 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure 2. A, Pain and B, PpIX fluorescence in mouse tails treated with vehicle or 
ALA cream 
 
 
 
 
 
Figure 3. A, Flow cytometry showing fluorescence in DRG cultured cells. Action 
potentials recorded from DRG neurons treated with ALA B, recorded extracellularly 
and C, using the whole-cell patch-clamp approach. 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 27 
 
 
 
 
 
 
 
 
Figure 4. A, Concentration-dependent inhibition of action potential frequency by 
menthol. B, Menthol does not affect PpIX-mediated fluorescence in ALA-treated 
mouse tails. C, Menthol caused a dose-dependent inhibition in PpIX fluorescence-
evoked pain behaviour in mice. 
 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 28 
 
 
Appendix 2  
A randomised, double-blind placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
Eudract No:  
2015-002849-59 
Product: 
menthol in aqueous cream 5% 
 
Simplified Investigator Brochure: Overview of clinical data to support proposed study 
Thorough Medline and Old Medline searches encompassing all years (through PubMed, 
NLM) were undertaken combining the search terms (menthol or levomenthol) AND (skin or 
cutaneous) AND (adverse effect) yielding 65 relevant publications.  Eleven abstracts of 
reports concerning topical application to the skin without occlusion were considered of 
potential relevance and these publications have been assessed and a summary of relevant 
adverse effects is reported. 
 
Topical menthol is a vasodilator (Craighead et al., 2017).  In the studies in which topical 
menthol has been used, no serious or notable advents have been reported.  Skin irritancy 
may occur (Liu et al., 2016, Yosipovitch et al., 1996), however irritancy is more likely with 
repeated applications of topical menthol, and with the single 10 minute application proposed 
in this study we would not expect this to be a factor.  A hyperalgesic tingling, prickling, cooling 
sensation can be experienced as an expected and often desirable effect of topical menthol 
(Wasner et al., 2004, Andersen et al., 2016).  However, again, in the proposed study, as it is 
only applied for 10 minutes and then patients are immediately treated with photodynamic 
therapy, we would not expect there to be any notable adverse effects.  The safety profile of 
topical peppermint and menthol and lack of any notable adverse effects have been 
highlighted (Nair, 2001, Higashi et al., 2010, Sabzghabaee et al., 2011).  The cooling 
sensation is likely to be one of the proposed mechanisms for pain relief and a desirable effect 
of topical menthol (Gillis et al., 2010, Andersen et al., 2015).   
In a study by Fallon and colleagues, cancer treatment-related neuropathic pain was studied in 
51 patients and 40 completed a 6 week treatment course of daily topical menthol in aqueous 
cream with beneficial effects on pain (Fallon et al., 2015).  Other objective parameters were 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 29 
 
 
also studied in that trial and there was a lack of any notable adverse effects with topical 
menthol using this repeated daily treatment regime over 6 weeks.  Of the eleven patients who 
discontinued treatment, only two did this because, as stated in the manuscript, they “disliked 
the cream”, but no other notable effects of topical menthol were described. 
 
In the study of Anderson and colleagues (Anderson et al., 2016), 14 healthy volunteers were 
investigated in a randomised double-blinded study of trans-cinnamaldehyde provoked 
neurogenic inflammation and hyperalgesia compared with trans-cinnamaldehyde combined 
with 40% levomenthol applied simultaneously.  The topical menthol reduced pain, 
hyperalgesia and inflammation, and other than the reporting of a cooling sensation in 
association with the combined trans-cinnamaldehyde and menthol treatment, there were no 
other side effects documented. 
 
Thus, in conclusion, whilst there may be some expected effects of topical menthol in terms of 
minor skin irritation and a cooling and hyperalgesic sensation, no other significant adverse 
effects are anticipated in the proposed study, with a single application of 10 minutes only of 
topical menthol. 
 
Reference safety information (RSI) 
Topical menthol may cause the effects of skin irritation, cooling and hyperalgesia and these 
would be expected, albeit minor and possibly even desirable effects.  We would not expect 
any serious adverse reactions in association with topical menthol as used in this study.  Thus, 
any serious adverse events would be considered as unexpected. 
 

 A randomised double blind, placebo controlled study of the efficacy of topical menthol 
for pain relief during topical photodynamic therapy 
v.6.0 27/March/2019 
 
 
 
Page 30 
 
 
References 
ANDERSEN, H. H., GAZERANI, P. & ARENDT-NIELSEN, L. (2016) High-Concentration L-Menthol 
Exhibits Counter-Irritancy to Neurogenic Inflammation, Thermal and Mechanical 
Hyperalgesia Caused by Trans-cinnamaldehyde. Journal of Pain, 17, 919-929 
ANDERSEN, H. H., POULSEN, J. N., UCHIDA, Y., NIKBAKHT, A., ARENDT-NIELSEN, L. & 
GAZERANI, P. (2015) Cold and L-menthol-induced sensitization in healthy volunteers-
a cold hypersensitivity analogue to the heat/capsaicin model. Pain, 156, 880-889 
CRAIGHEAD, D. H., MCCARTNEY, N. B., TUMLINSON, J. H. & ALEXANDER, L. M. (2017) 
Mechanisms and tie course of menthol-induced cutaneous vasodilation. 
Microvascular Research, 110, 43-47 
FALLON, M. T., STOREY, D. J., KRISHAN, A., WEIR, C. J., MITCHELL, R., FLEETWOOD-WALKER, 
S. M., SCOTT, A. C. & COLVIN, L. A. (2015) Cancer treatment-related neuropathic 
pain: proof of concept study with menthol-a TRPM8 agonist. Supportive Care in 
Cancer, 23, 2769-2777 
GILLIS, D. J., HOUSE, J. R. & TIPTON, M. J. (2010) The influence of menthol on 
thermoregulation and perception during exercise in warm, humid conditions. 
European Journal of Applied Physiology, 110, 609-618 
HIGASHI, Y., KIUCHI, T. & FURUTA, K. (2010) Efficacy and Safety Profile of a Topical Methyl 
Salicylate and Menthol Patch in Adult Patients With Mild to Moderate Muscle Strain: 
A Randomized, Double-Blind, Parallel-Group, Placebo-Controlled, Multicenter Study. 
Clinical Therapeutics, 32, 34-43 
LIU, D. J., COLLAKU, A. & DOSIK, J. S. (2016) Skin irritation and sensitization potential of fixed-
dose combination of Diclofenac 1% and Menthol 3% topical gel: results of two Phase 
1 Patch studies. Drug Research (Stuttgard Germany),  
NAIR, B. (2001) Final report on the safety assessment of Mentha Piperita (Peppermint) Oil, 
Mentha Piperita (Peppermint) Leaf Extract, Mentha Piperita (Peppermint) Leaf, and 
Mentha Piperita (Peppermint) Leaf Water. International Journal of Toxicology, 20, 
61-73 
SABZGHABAEE, A. M., NILI, F., GHANNADI, A., EIZADI-MOOD, N. & ANVARI, M. (2011) Role of 
menthol in treatment of candidial napkin dermatitis. World Journal of Pediatrics, 7, 
167-170 
WASNER, G., SCHATTSHNEIDER, J., BINDER, A. & BARON, R. (2004) Topical menthol--a 
human model for cold pain by activation and sensitization of C nociceptors. Brain, 
127, 1159-71 
YOSIPOVITCH, G., SZOLAR, C., HUI, X. Y. & MAIBACH, H. (1996) Effect of topically applied 
menthol on thermal, pain and itch sensations and biophysical properties of the skin. 
Archives of Dermatological Research, 288, 245-248