The FDA issued a safety alert warning healthcare providers and patients of the potential spread of monkeypox virus through fecal microbiota transplantation (FMT) products, noting that additional safety precautions are needed.
Recent studies reported that monkeypox virus DNA was detected in rectal swabs and/or stool samples from infected individuals. One study found viral DNA in rectal swabs among three asymptomatic individuals, including two with viable virus isolated from the swabs.
“This information suggests that monkeypox virus may be transmitted through FMT products, although the risk of such transmission is unknown,” the agency wrote.
Transmission of monkeypox primarily occurs when individuals come within close contact of an infected, symptomatic person. However, it has been unclear whether the virus could spread via an asymptomatic individual or through feces.
The FDA noted that there are limited data on the availability and sensitivity of direct stool testing for monkeypox.
Due to the potential for serious adverse events, the agency advised that any investigational use of FMT or stool donated after March 15 should be subject to additional protections, including screening questions to identify donors who are currently or were recently infected, or at high risk for monkeypox, in addition to the development of exclusion criteria for donors/stool based on screening. Informed patient consent should also be obtained with information on the potential spread of monkeypox via FMT, including from asymptomatic donors.
Investigational new drug application (IND) holders should be notified of the potential risks and should implement added safety protections.
FMT is used as an investigational treatment for Clostridium difficile (C. difficile) infection in patients who have not responded to standard therapies, and these products have also been studied in numerous conditions, including ulcerative colitis, among others. FDA guidance on the use of FMT products notes that patient consent “should include, at a minimum, a statement that the use of FMT to treat C. difficile is investigational and a discussion of its potential risks.”
The agency is encouraging patients and healthcare professionals to report adverse events involving FMT to the FDA MedWatch program.