CHICAGO, Aug 4 – With the number of monkeypox cases rising in the U.S., U.S. health agencies defended their decision to require data from human studies to show that SIGA Technologies’ ( SIGA . O) is safe and effective in treating the virus.
US agencies have been under pressure to ease access to the drug, which is distributed by the US Centers for Disease Control and Prevention (CDC) under a special “compassionate use” approach that requires doctors to request it from the agency or their health department. and enroll each patient in the study.
As of July 22, 223 people had been treated with the drug, compared to more than 6,000 known cases in the United States.
The FDA approved TPOXX in 2018 for smallpox in adults and children based on studies in animals infected with monkeypox and rabbitpox, as well as safety data in healthy humans. It can only be sold to the US Strategic National Stockpile.
The authors of an article in the New England Journal of Medicine from the Food and Drug Administration, the CDC, and the National Institutes of Health (NIH) said the latter is planning a randomized clinical trial in the US.
Data from this study will be used to determine whether the drug will gain approval in the US for monkeypox.
The drug, also known as tecovirimat, is approved for both chickenpox and monkeypox in the UK and Europe. It has been approved by the European Union under the “exceptional circumstances” method, which allows marketing approval when data cannot be obtained even after authorization.
Although TPOXX has only been tested in healthy people, the European Medicines Agency said it expected side effects to be similar in infected people and considered the drug’s benefits to be greater than its risks.
Dr. Jay Varma, director of the Cornell Center for Pandemic Prevention and Response, who has advocated for broader access to the drug, said the FDA’s standards ensure that American drugs are safe and set a high bar for the world, but in some circumstances, strict standards hurt us.
At the start of the current outbreak in May, there were 1.7 million doses of treatment in the US strategic national stockpile.
On July 21, the CDC and FDA began allowing doctors to prescribe the drug before trial documentation is complete, but it still requires hospital institutional review board approval for each dose.
“It’s better. It’s still very taxing,” said Dr. Karen Krueger, an infectious disease expert at Northwestern Medicine in Chicago, said additional paperwork is needed after a patient visit and several follow-up visits.
“It’s doable, but certainly much more challenging than how we normally prescribe drugs.”
Neither the FDA nor the CDC immediately responded to a request for comment.
Northwestern has treated at least 20 monkeypox patients with TPOXX and will be one of the sites for the NIH study.
SIGA Chief Scientific Officer Dennis Hruby estimates that a 500-patient, placebo-controlled clinical trial in the United States will likely be needed to gain approval.
If the caseload remains high, the process may be fully enrolled within a few months. “It’s not a very long process,” he said.
SIGA CEO Phillip Gomez said the company is working to start trials in the UK, Canada, the United States, and Europe.
If the United States declares monkeypox a national emergency, Gomez said the drug could be granted an emergency use permit. However, because the FDA has been “very clear” they want full, placebo-controlled studies, which may take some time, he said.