Clinical Trial Details
— Status: Terminated
Administrative data
NCT number |
NCT02354144 |
Other study ID # |
A10-M98-14B |
Secondary ID |
CIHR-MOP-137066C |
Status |
Terminated |
Phase |
Phase 2/Phase 3
|
First received |
|
Last updated |
|
Start date |
February 2016 |
Est. completion date |
March 9, 2020 |
Study information
Verified date |
May 2021 |
Source |
McGill University |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The LIMIT-Study is a placebo-controlled, double-blinded randomized controlled trial designed
to explore the efficacy of a carrageenan-based lubricant as a topical microbicide for
preventing HPV acquisition. Individuals at high risk for infection (men who have sex with
men, or MSM, and especially those with HIV) will be included in the trial. Participants will
complete a self-administered baseline questionnaire during the enrollment visit, and
follow-up questionnaires during all other six visits. The shorter follow-up questionnaires
are intended to evaluate recent sexual behaviours and to corroborate the responses given
during the baseline visit. These questionnaires will measure HPV risk factors, compliance,
and monitor safety and tolerability of the gels. Between follow-up visits, participants will
be asked to log into a secure web module at least once a week to answer questions on daily
sexual activities, condom and study gel use, and adverse events. Individuals will be screened
for eligibility over the telephone or in person and eligible men will attend an enrollment
visit, where the nurse will obtain informed consent and instruct the participant on gel use.
They will receive a one month's supply of gel and provide the first specimen. Random number
sets will be assigned to the treatment and control gel. Each participant will be assigned an
individual code, which will be used to match him to the study arm. Lastly, the nurse will
provide details about HPV infection and advice about condom use and sexual health. HPV
infection status will be measured using anal specimens at baseline (enrollment/time 0), and
at all follow-up clinic visits (1, 2, 3, 6, 9 and 12 months).
Description:
Human papillomavirus (HPV) inhibitory compounds might be useful as topical microbicides for
blocking the spread of HPV. Recent in-vitro and in-vivo laboratory studies have demonstrated
the strong inhibitory properties of carrageenan (an inexpensive gelling agent that is
non-toxic and safe in animals and humans) against all HPV types. So far, there has been no
clinical trial designed to assess a carrageenan-based personal lubricant as a topical
microbicide in the Men who have Sex with Men (MSM) population. Since the introduction of
HAART therapy in 1996, there has been a paradoxical effect on the incidence of anal cancer, a
disease caused by HPV. Whereas patients would formerly die of some other AIDS-related
ailment, men undergoing HAART therapy now have increased longevity, thus allowing diseases
with longer natural history such as anal cancer to develop. Low cluster of differentiation 4
(CD4) counts, high HPV incidence and longer duration of infection have contributed to
elevating the risk of anal lesions and cancer among MSMs with HIV to nearly 80 times that of
the general male population. Although HPV vaccination has been approved for males in Canada,
it is exclusively prophylactic, i.e. it will only prevent HPV infection before exposure
occurs. But considering that most MSMs will have already been exposed to the vaccine target
types, its benefits in this population are limited. Furthermore, current vaccination only
protects against two of the 14 oncogenic HPV types.
The primary aim of the study is to evaluate the efficacy of carrageenan in reducing
type-specific anal HPV incidence, i.e., in preventing infections by new HPV types in sexually
active MSM. Secondary aims are: 1) to evaluate the efficacy of carrageenan in reducing
type-specific anal HPV prevalence, i.e., in accelerating clearance of existing infections in
sexually active MSM; 2) to compare the efficacy of carrageenan for type-specific prevention
and clearance of anal HPV infections among MSM with and without HIV, i.e., to evaluate
whether carrageenan is equally effective among these subgroups; and 3) to assess the safety
and tolerability of the proposed gel and patient adherence to the intervention, i.e., the
parameters important for future clinical use.
To permit verification of the study's objectives with sufficient power at the end of the
one-year follow-up period, we propose to recruit 380 subjects (110 HIV+ and 270 HIV-). We
will be recruiting subjects living with HIV through 5 HIV/AIDS outpatient clinics in
Montreal: Clinique Médicale du Quartier-Latin, Clinique L'Actuel, Clinique OPUS, Unité
d'Hospitalisation de Recherche et d'Enseignement sur les Soins du SIDA (UHRESS) of the Centre
Hospitalier de L'Université de Montréal (CHUM) and Chronic Viral Illnesses Service of McGill
University Health Centre (MUHC). We will advertise at bars, sex and health clubs, in various
media, and the abovementioned clinics-with the addition of the McGill University Student
Health Services. MSMs with and without HIV will be recruited. For those with HIV, a chart
review will be performed at enrollment to collect information on CD4+ count, viral load,
HAART status, year of HIV diagnosis, and nadir CD4+ count. HIV testing will also be performed
on MSMs without HIV to verify their status.
Volunteer MSMs living in Montreal will be randomized to receive either a) treatment with
carrageenan self-applied as an anal microbicide gel, or b) treatment with a placebo gel
applied in the same way. Our specific primary aim is to evaluate the efficacy of carrageenan
in reducing anal HPV incidence, i.e., in preventing new HPV infections in sexually active
MSMs. Additional secondary aims include: to evaluate the efficacy of carrageenan in reducing
anal HPV prevalence (i.e., in accelerating clearance of existing infections in sexually
active MSMs), to evaluate if there is a difference in the efficacy of carrageenan for
prevention and clearance of HPV infections between individuals living with and without HIV,
and to evaluate patient adherence as measured by behavioural characteristics assessed by
means of questionnaires.
Participants will be randomized to either carrageenan or placebo gels by a variable block
randomization algorithm and blinded intervention. Demographics, risk factor, and compliance
information will be collected via computerized questionnaires at baseline (enrollment/ time
0), and 1, 2, 3, 6, 9 and 12 months post-enrollment. HPV DNA detection and genotyping of anal
samples will be done at the same clinic visits by the PGMY polymerase chain reaction
protocol. Measuring the efficacy of the intervention will be done by testing the null
hypothesis of no difference in time to HPV infection (i.e., infection with an HPV type not
present at baseline) between treatment groups with the log rank test. We will use a Cox
proportional hazards regression model to estimate the hazard ratio and 95% confidence
intervals of HPV infection for the treatment versus placebo group. We will also use survival
analysis techniques to measure clearance of infections with HPV types present at enrollment
according to the intervention. Our analyses will be conducted separately according to
participant HIV status, and eventually pooled if results are found to be similar between
groups. We will perform our analyses according to the intention-to-treat approach (i.e.,
including all participants who were randomized and received at least one-month's supply of
gel), and the according-to-protocol approach (i.e., including only participants who complied
with the protocol).
Considering that HPV infection is responsible for 90% of anal cancer cases, as well as for
much suffering due to genital warts, the potential for this microbicide-based approach in
disease prevention cannot be overemphasized. Our team has extensive experience in studies of
HPV epidemiology in Montreal and subject recruitment resources are already in place.
(Full protocol available upon request)