Tecovirimat for Monkeypox

(STOMP Trial)

Recruiting at 83 trial locations

Overseen By ACTG Clinicaltrials.gov Coordinator

Age: Any Age

Sex: Any

Trial Phase: Phase 3

Sponsor: National Institute of Allergy and Infectious Diseases (NIAID)

Must not be taking: Tecovirimat, Cabotegravir/Rilpivirine

Disqualifiers: Pregnancy, Severe risk, others

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 59

Duration: 14 days

719 Participants Needed

Trial Summary

What is the purpose of this trial?

A5418 is a randomized, placebo-controlled, double-blind study to establish the efficacy of tecovirimat for the treatment of people with laboratory-confirmed or presumptive HMPXV disease.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but you cannot start new intramuscular cabotegravir/rilpivirine during the study or for two weeks after. If you are already stable on these medications, you can still join the trial.

What data supports the effectiveness of the drug tecovirimat for treating monkeypox?

Research shows that tecovirimat is effective against the monkeypox virus in lab settings and has been used successfully in patients during outbreaks. It is approved for smallpox, a related virus, and has shown promise in treating monkeypox due to similarities between the viruses. ^{1 2 3 4 5}

Is tecovirimat safe for humans?

Tecovirimat, also known as TPOXX or ST-246, is generally considered safe for humans. In a study involving 549 patients treated for monkeypox, only 3.5% reported adverse events, and all but one were nonserious. This suggests that tecovirimat is safe for use in treating monkeypox, although monitoring for side effects is important. ^{1 2 3 6 7}

How does the drug tecovirimat differ from other treatments for monkeypox?

Tecovirimat is unique because it is an antiviral drug specifically targeting orthopoxviruses, including monkeypox, by inhibiting a viral protein essential for the virus's spread. Unlike other treatments, it is FDA-approved for smallpox and is being used for monkeypox under an investigational protocol, showing promise in animal studies and early human use. ^{1 2 6 8 9}

Research Team

Timothy Wilkin, MD, MPH

Principal Investigator

Cornell

Eligibility Criteria

Adults (≥18 years) with confirmed or suspected Monkeypox virus infection, showing symptoms for less than 14 days and at least one active lesion. Must agree to use contraception if of reproductive potential. Children, severely ill patients, those with severe immunosuppression or skin conditions that increase risk are in a separate group.

Inclusion Criteria

Non-pregnant people of reproductive potential must agree to use at least one effective means of contraception when engaging in sexual activities that can result in pregnancy, from the time of enrollment through the end of study participation

I am 18 years old or older.

Laboratory-confirmed or presumptive HMPXV infection

Exclusion Criteria

I need tecovirimat through an IV.

I plan to start or continue cabotegravir/rilpivirine injections during or after the study.

Participants who, in the judgement of the investigator, will be at significantly increased risk as a result of participation in the study

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive either tecovirimat or placebo for 14 days. Participants with severe disease or specific conditions receive open-label tecovirimat.

14 days

Weekly visits through day 29

Follow-up

Participants self-monitor lesions and symptoms daily through 29 days or until resolution. Weekly assessments for HMPXV disease and safety.

29 days

Weekly visits through day 29, additional visit on day 57

Long-term follow-up

Participants are assessed at day 57 for possible recrudescence of infection.

28 days after treatment

1 visit (in-person) on day 57

Treatment Details

Interventions

• Placebo
• Tecovirimat

Trial Overview The study is testing the effectiveness of Tecovirimat capsules against Monkeypox compared to a placebo. Participants are randomly assigned to receive either the medication or placebo without knowing which they're getting. There's also an open-label part for certain participants.

Participant Groups

Group I: Arm C Experimental Treatment 1 Intervention

Group II: Arm A Experimental Treatment 1 Intervention

Group III: Arm B Placebo Group 1 Intervention

Who Is Running the Clinical Trial?

National Institute of Allergy and Infectious Diseases (NIAID)

Lead Sponsor

Trials

3,361

Recruited

5,516,000+

SIGA Technologist

Collaborator

Trials

1

Recruited

720+

SIGA Technologies

Industry Sponsor

Trials

11

Recruited

2,000+

Findings from Research

Tecovirimat (ST-246) has been shown to be effective against the monkeypox virus (MPXV) isolate from the first clinical case in France, requiring only nanomolar concentrations for efficacy, which is significantly lower than the micromolar concentrations needed for cidofovir.

These findings support the ongoing use of tecovirimat in human clinical trials for treating monkeypox, highlighting its potential as a preferred treatment option during the current outbreak.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Tecovirimat is effective against human monkeypox virus in vitro at nanomolar concentrations. Frenois-Veyrat, G., Gallardo, F., Gorgé, O., et al.[2023]

This study will evaluate the efficacy and safety of oral tecovirimat in treating monkeypox and smallpox, involving 50 patients and focusing on the percentage of patients achieving negative PCR results for skin lesions after 14 days of treatment.

Participants will choose between receiving tecovirimat plus supportive treatment or only supportive treatment, with the study covering costs to ensure accessibility, highlighting a commitment to ethical research practices.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Protocol of Tecopox study: a multicentre, open-label, double-arm trial to evaluate the efficacy and safety of oral tecovirimat therapy for patients with smallpox or monkeypox. Suzuki, T., Saito, S., Tsuzuki, S., et al.[2023]

Tecovirimat (TPOXX®) is an antiviral drug specifically designed to target orthopoxviruses, including the variola virus that causes smallpox, by inhibiting a key protein necessary for the virus's spread within the host.

Approved in July 2018 for treating smallpox in patients weighing 13 kg or more, tecovirimat's efficacy was demonstrated through animal studies, allowing it to gain approval under the FDA's Animal Rule.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Tecovirimat: First Global Approval. Hoy, SM.[2022]

References

1. England pubmed.ncbi.nlm.nih.gov

Tecovirimat is effective against human monkeypox virus in vitro at nanomolar concentrations. [2023]

2. England pubmed.ncbi.nlm.nih.gov

Protocol of Tecopox study: a multicentre, open-label, double-arm trial to evaluate the efficacy and safety of oral tecovirimat therapy for patients with smallpox or monkeypox. [2023]

3. United States pubmed.ncbi.nlm.nih.gov

Clinical features and management of human monkeypox: a retrospective observational study in the UK. [2023]

4. United States pubmed.ncbi.nlm.nih.gov

Monkeypox treatment: Current evidence and future perspectives. [2023]

5. United States pubmed.ncbi.nlm.nih.gov

Tecovirimat for the Treatment of Human Monkeypox: An Initial Series From Massachusetts, United States. [2023]

6. United States pubmed.ncbi.nlm.nih.gov

Clinical Use of Tecovirimat (Tpoxx) for Treatment of Monkeypox Under an Investigational New Drug Protocol - United States, May-August 2022. [2023]

7. Denmark pubmed.ncbi.nlm.nih.gov

Progression of human monkeypox infection despite tecovirimat in an immunocompromised adult. [2023]

8. New Zealand pubmed.ncbi.nlm.nih.gov

Tecovirimat: First Global Approval. [2022]

9. United States pubmed.ncbi.nlm.nih.gov

New Perspectives on Antimicrobial Agents: Tecovirimat for Treatment of Human Monkeypox Virus. [2023]