Monkeypox treatment trial begins in the Democratic Republic of the Congo
A clinical trial to evaluate the antiviral drug tecovirimat, also known as TPOXX, in adults and children with monkeypox has begun in the Democratic Republic of the Congo (DRC). The trial will evaluate the drug’s safety and its ability to mitigate monkeypox symptoms and prevent serious outcomes, including death.
The National Institute of Allergy and Infectious Diseases (NIAID), part of the U.S. National Institutes of Health, and the DRC’s National Institute for Biomedical Research (INRB) are co-leading the trial as part of the government-to-government PALM partnership. Collaborating institutions include the U.S. Centers for Disease Control and Prevention (CDC), the Institute of Tropical Medicine Antwerp, the aid organization Alliance for International Medical Action (ALIMA) and the World Health Organization (WHO).
TPOXX, made by the pharmaceutical company SIGA Technologies, Inc. (New York), is approved by the U.S. Food and Drug Administration for the treatment of smallpox. The drug impedes the spread of virus in the body by preventing virus particles from exiting human cells. The drug targets a protein that is found on both the virus that causes smallpox and the monkeypox virus.
The trial will enroll up to 450 adults and children with laboratory-confirmed monkeypox infection who weigh at least 3 kilograms (kg). Pregnant women are also eligible to enroll. The volunteer participants will be assigned at random to receive either oral tecovirimat or placebo capsules twice daily for 14 days, with the dose administered dependent on the participant’s weight. The trial is double-blinded, so participants and investigators do not know who will receive tecovirimat or placebo.
All participants will stay at a hospital for at least 14 days where they will receive supportive care. Study clinicians will regularly monitor participants’ clinical status throughout the study, and participants will be asked to provide blood, throat swab, and skin lesion swab samples for laboratory evaluations. The study is primarily designed to compare the average time to healed skin lesions among those receiving tecovirimat versus those receiving placebo. Investigators will also gather data on multiple secondary objectives, including comparisons of how quickly participants test negative for monkeypox virus in the blood, overall severity and duration of disease, and mortality between groups.
Participants will be discharged from the hospital once all lesions have scabbed over or flaked off, and after they test negative for monkeypox virus in the blood for two days in a row. They will be followed for at least 28 days and will be asked to return for an optional study visit after 58 days for additional clinical and laboratory tests. An independent Data and Safety Monitoring Board will monitor participant safety throughout the duration of the study.
