MonkeypoxPhase 3PLATINUM-CANNCT05534165
Tecovirimat in Non-hospitalized Patients With Monkeypox
A Phase 3 study testing Tecovirimat in people with Monkeypox, run by Marina Klein at 3 sites in Canada.
Trial summary
PLATINUM-CAN is a parallel collaborative trial linked with the sister trial PLATINUM led by Oxford University. PLATINUM-CAN is a multi-centre, randomized, placebo-controlled trial of Tecovirimat in non-hospitalized patients with presumptive or PCR confirmed monkeypox infection. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Monkeypox
- What is being tested?
- Tecovirimat
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 120 participants
- Where
- 3 sitesCanada
- Study dates
- 14 Aug 2023to 31 Mar 2026
- Phase
- Phase 3
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Any sex, ≥ 18 years of age inclusive at the time of signing informed consent.
- Weight ≥ 40 kg
- Laboratory-confirmed or presumptive monkeypox infection:
- Laboratory-confirmed monkeypox infection is defined as determined by PCR, culture, or antigen test obtained from a sample collected from blood, oropharynx, anal or skin lesion within 4 days of randomization OR
- Presumptive diagnosis:
- Skin lesion(s), mucosal lesion(s) or proctitis consistent with a high probability of monkeypox infection in the opinion of the site investigator AND
Show all 9Show fewer
- Sexual contact with 1 or more persons in the 21 days prior to symptom onset or any person with known close exposure to another person known to be infected with monkeypox infection. Presence of active skin or mucosal lesion(s).
- Appropriate to be managed without hospitalization.
- The participant (or legally acceptable representative) has provided documented informed consent and comply to the require procedures for the study.
Who cannot join
- Weight < 40 kg
- Current or past use of tecovirimat
- Inability to provide informed consent
- The patient's own doctor considers there to be either a definite indication or a definite contraindication to the patient receiving tecovirimat
- Participated in an interventional clinical study < 28 days prior to the day of first IP administration (Day 0) or plans to do so while enrolled in this study.
Trial locations and contacts
3 sites in 1 country.
Canada3 sites
St. Michael's Hospital
Toronto, Ontario, M5B 1W8
Toronto General Hospital
Toronto, Ontario, M5G 2N2
St. Paul's Hospital, BC Centre for Excellence in HIV/AIDS
Vancouver, British Columbia, V6Z 1Y6
About this study
Official title: Placebo-controlled Randomized Trial of Tecovirimat in Non-hospitalized Patients With Monkeypox: Canadian Feasibility Study (PLATINUM-CAN)
PLATINUM-CAN is a parallel collaborative trial linked with the sister trial PLATINUM led by Oxford University. PLATINUM-CAN is a multi-centre, randomized, placebo-controlled trial of Tecovirimat in non-hospitalized patients with presumptive or PCR confirmed monkeypox infection. The study will provide evidence on the efficacy and safety of Tecovirimat for laboratory-confirmed monkeypox in outpatients with monkeypox infection and determine the feasibility of conducting interventional monkeypox trials in Canada.
Read the detailed description
In order to generate needed therapeutic efficacy evidence rapidly, international collaboration is essential. PLATINUM-CAN is a parallel collaborative trial linked with the sister trial PLATINUM led by Oxford University. Given the rapidly evolving epidemic and important differences in healthcare contexts and public health systems between countries that could impact the number of cases and access to diagnosis and treatment, a Canadian study is warranted to assess the feasibility and acceptability of conducting large scale interventional monkeypox trials in Canada. Such a focused trial also allows for the opportunity to explore a number of secondary objectives that can address concerns raised during consultation with Canadian community members (e.g., resolution of pain, quality of life) and validate use of self-assessed primary outcomes using blinded photography assessment.
The trial is pragmatic and minimizes number of visits, tests performed and contacts with the healthcare system through use of self-assessment diaries and self-testing. Lesion and/or throat swabs taken as part of standard care will be sent for detection of monkeypox virus DNA by PCR to local public health/provincial laboratories for initial screening (using panorthopox DNA testing) and confirmation with monkeypox specific PCR either locally or by National Microbiology Laboratory. The protocol allows for a broad range of patients to be enrolled. The trial has been designed so that it can accommodate patients who may be assessed in a variety of medical settings (e.g., hospital emergency rooms, outpatient HIV and infectious diseases clinics, community sexual health clinics, primary care, or through public health services). Similarly, we will ensure our trial design is able to contribute to global efforts such as the core protocol for the evaluation of treatments for human monkeypox (led by the Institut National de Recherche Biomédicale (INRB)/ANRS/NIAID in collaboration with WHO) and the AIDS Clinical Trials Group (ACTG) STOMP protocol.
As a feasibility study, PLATINUM CAN is underpowered for evaluating a primary endpoint of time to active lesion resolution. To achieve full study power, results will be combined with the sister study, PLATINUM-UK (n=500), being conducted at Oxford University, UK of similar design using a pre-planned individual patient meta-analysis. In addition to feasibility outcomes, the trial will evaluate the correlation between the time to active and complete resolution of lesions between self-report and blinded photographic validation from an adjudication committee, in consenting participants.
- Conditions
- Monkeypox
- Being tested
- Tecovirimat, Placebo
- Keywords
- Tecovirimat, Randomized, Placebo-Controlled, Outpatients, Non-hospitalized, Feasibility
- Medical subject headings
- Mpox, Monkeypox
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
TecovirimatDrug
Also called TPOXX
600 mg po BID
PlaceboDrug
identical placebo 600 mg po BID
| Study group | Role | What they receive |
|---|---|---|
| Tecovirimat | Experimental | Tecovirimat (TPOXX®) Capsules, 200 mg (as tecovirimat monohydrate) administered as 600 mg (three 200 mg capsules) taken twice daily orally, every 12 hours, within 30 minutes after a full meal of moderate or high fat (approximately 25 g of fat) for 14 days Receives: Drug: Tecovirimat |
| Placebo | Placebo comparator | Identical placebo supplied by SIGA Technologies Inc. Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Time to active lesion resolution
Time (days) to active lesion resolution, defined as the first day on which all skin lesions are scabbed or desquamated (and mucosal lesions healed).
Measured: Up to 28 days after randomization
Feasibility and acceptability of conducting a pragmatic phase 3 interventional trial for outpatients with Monkeypox in Canada
Number of eligible patients per month and proportion randomized
Measured: 4 months
Secondary outcomes (4)
Time to complete lesion resolution
Time (days) to complete lesion resolution, defined as the first day on which all lesions are completely resolved (all scabs dropped off and intact skin remains underneath, mucosal lesions healed)
Measured: Up to 28 days after randomization
Time to negative throat swab viral culture
Defined as time to consistently negative culture for monkeypox virus on throat swab
Measured: Days 7, 14, 21, and 28
Time to negative skin or mucosa swab viral culture
Defined as time to consistently negative culture for monkeypox virus on swab of most recent active skin or mucosa
Measured: Days 7, 14, 21, and 28
Secondary feasibility outcomes
the proportion who adhere to at least 85% of daily questionnaires and self-sampling, and the proportion of participants who are able to complete all protocol procedures
Measured: 4 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Sep 2022
- Study start14 Aug 2023
- Primary completion13 Mar 2025
- Study completion31 Mar 2026 (estimated)
Why it stopped: The recommendations of the Data Safety Monitoring Committee, based on the results of the STOMP Study (NCT05534984).
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for MonkeypoxStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Randomized 1:1
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 120 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Marina Klein
- Sponsor type
- University, hospital or other
- Collaborators
- McGill University Health Centre/Research Institute of the McGill University Health Centre, University Health Network, Toronto, Unity Health Toronto, University of British Columbia, CIHR Canadian HIV Trials Network
- Responsible party
- Sponsor-investigator, Marina Klein, McGill University Health Centre/Research Institute of the McGill University Health Centre
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05534165
- Sponsor's protocol ID
- CTN 338
- Acronym
- PLATINUM-CAN
- Status last verified
- Mar 2026
- First submitted
- 2 Sep 2022
- Last updated
- 4 Mar 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 4 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Placebo-controlled Randomized Trial of Tecovirimat in Non-hospitalized Patients With Monkeypox: Canadian Feasibility Study (PLATINUM-CAN)
- ClinicalTrials.gov ID
- NCT05534165
- Acronym / sponsor ID
- PLATINUM-CAN / CTN 338
- Conditions
- Monkeypox
- Keywords
- Tecovirimat, Randomized, Placebo-Controlled, Outpatients, Non-hospitalized, Feasibility
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- SuspendedReason stopped: The recommendations of the Data Safety Monitoring Committee, based on the results of the STOMP Study (NCT05534984).
- Enrolment
- 120 participants (estimated)
- Lead sponsor
- Marina KleinUniversity, hospital or other
- Collaborators
- McGill University Health Centre/Research Institute of the McGill University Health Centre, University Health Network, Toronto, Unity Health Toronto, University of British Columbia, CIHR Canadian HIV Trials Network
- Study start
- 14 Aug 2023 (actual)
- Primary completion
- 13 Mar 2025 (actual)
- Study completion
- 31 Mar 2026 (estimated)
- First posted
- 9 Sep 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
PLATINUM-CAN is a parallel collaborative trial linked with the sister trial PLATINUM led by Oxford University. PLATINUM-CAN is a multi-centre, randomized, placebo-controlled trial of Tecovirimat in non-hospitalized patients with presumptive or PCR confirmed monkeypox infection. The study will provide evidence on the efficacy and safety of Tecovirimat for laboratory-confirmed monkeypox in outpatients with monkeypox infection and determine the feasibility of conducting interventional monkeypox trials in Canada.
Detailed description
In order to generate needed therapeutic efficacy evidence rapidly, international collaboration is essential. PLATINUM-CAN is a parallel collaborative trial linked with the sister trial PLATINUM led by Oxford University. Given the rapidly evolving epidemic and important differences in healthcare contexts and public health systems between countries that could impact the number of cases and access to diagnosis and treatment, a Canadian study is warranted to assess the feasibility and acceptability of conducting large scale interventional monkeypox trials in Canada. Such a focused trial also allows for the opportunity to explore a number of secondary objectives that can address concerns raised during consultation with Canadian community members (e.g., resolution of pain, quality of life) and validate use of self-assessed primary outcomes using blinded photography assessment.
The trial is pragmatic and minimizes number of visits, tests performed and contacts with the healthcare system through use of self-assessment diaries and self-testing. Lesion and/or throat swabs taken as part of standard care will be sent for detection of monkeypox virus DNA by PCR to local public health/provincial laboratories for initial screening (using panorthopox DNA testing) and confirmation with monkeypox specific PCR either locally or by National Microbiology Laboratory. The protocol allows for a broad range of patients to be enrolled. The trial has been designed so that it can accommodate patients who may be assessed in a variety of medical settings (e.g., hospital emergency rooms, outpatient HIV and infectious diseases clinics, community sexual health clinics, primary care, or through public health services). Similarly, we will ensure our trial design is able to contribute to global efforts such as the core protocol for the evaluation of treatments for human monkeypox (led by the Institut National de Recherche Biomédicale (INRB)/ANRS/NIAID in collaboration with WHO) and the AIDS Clinical Trials Group (ACTG) STOMP protocol.
As a feasibility study, PLATINUM CAN is underpowered for evaluating a primary endpoint of time to active lesion resolution. To achieve full study power, results will be combined with the sister study, PLATINUM-UK (n=500), being conducted at Oxford University, UK of similar design using a pre-planned individual patient meta-analysis. In addition to feasibility outcomes, the trial will evaluate the correlation between the time to active and complete resolution of lesions between self-report and blinded photographic validation from an adjudication committee, in consenting participants.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- Randomized 1:1
| Arm | Type | Receives |
|---|---|---|
| Tecovirimat | Experimental | Drug: TecovirimatTecovirimat (TPOXX®) Capsules, 200 mg (as tecovirimat monohydrate) administered as 600 mg (three 200 mg capsules) taken twice daily orally, every 12 hours, within 30 minutes after a full meal of moderate or high fat (approximately 25 g of fat) for 14 days |
| Placebo | Placebo comparator | Drug: PlaceboIdentical placebo supplied by SIGA Technologies Inc. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (9 listed)
- Any sex, ≥ 18 years of age inclusive at the time of signing informed consent.
- Weight ≥ 40 kg
- Laboratory-confirmed or presumptive monkeypox infection:
- Laboratory-confirmed monkeypox infection is defined as determined by PCR, culture, or antigen test obtained from a sample collected from blood, oropharynx, anal or skin lesion within 4 days of randomization OR
- Appropriate to be managed without hospitalization.
Key exclusion criteria (5 listed)
- Weight < 40 kg
- Current or past use of tecovirimat
- Inability to provide informed consent
- The patient's own doctor considers there to be either a definite indication or a definite contraindication to the patient receiving tecovirimat
- Participated in an interventional clinical study < 28 days prior to the day of first IP administration (Day 0) or plans to do so while enrolled in this study.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| TecovirimatAlso: TPOXX600 mg po BID | Drug | Tecovirimat |
| Placeboidentical placebo 600 mg po BID | Drug | Placebo |
Primary outcome
Time to active lesion resolution
Time frame: Up to 28 days after randomization
Time (days) to active lesion resolution, defined as the first day on which all skin lesions are scabbed or desquamated (and mucosal lesions healed).
Feasibility and acceptability of conducting a pragmatic phase 3 interventional trial for outpatients with Monkeypox in Canada
Time frame: 4 months
Number of eligible patients per month and proportion randomized
4 secondary outcomes
Time to complete lesion resolution
Time frame: Up to 28 days after randomization
Time to negative throat swab viral culture
Time frame: Days 7, 14, 21, and 28
Time to negative skin or mucosa swab viral culture
Time frame: Days 7, 14, 21, and 28
Secondary feasibility outcomes
Time frame: 4 months
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Mar 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
3 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Tecovirimat in people with Monkeypox, run by Marina Klein at 3 sites in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: paused, as of the sponsor's last update on 4 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 3 sites in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Time to active lesion resolution (time frame: Up to 28 days after randomization). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Mar 2026.