As mpox continues As the virus spreads across Central Africa, a promising antiviral drug intended to treat the infection failed to improve symptoms in patients in a study conducted in the Democratic Republic of Congo, the epicenter of the outbreak.
In the study, the drug tecovirimat, also known as TPOXX, did not alleviate the characteristic blister-like rash seen in people with mpox, formerly known as monkeypox. In an unusual step, the U.S. National Institute of Allergy and Infectious Diseases (NIAID), which sponsored the study, announced preliminary results earlier this month before the full results are peer-reviewed and published in a scientific journal.
Lori Dodd, chief of NIAID’s clinical trials and statistics division, tells WIRED that the agency released the preliminary results “because of the urgent need for scientific evidence to support the use of tecovirimat in treating mpox.” That urgency, she says, was reinforced by the World Health Organization declaring the mpox outbreak in Central Africa a global health threat August 14. This is the second such declaration in two years.
The results are disappointing, especially as Central African countries struggle to contain the transmission of mpox. Since the beginning of this year, 13 African countries have recorded a total of 20,720 confirmed or suspected cases of mpox and 582 deaths, according to Report from August 25 from the Africa Centers for Disease Control and Prevention.
On Monday, the World Health Organization a six-month strategic plan was launched to control the outbreak. The $135 million plan includes strengthening surveillance efforts, as well as improving access to testing and vaccines. “The mpox outbreaks in the Democratic Republic of the Congo and neighboring countries are controllable and containable,” WHO Director-General Tedros Adhanom Ghebreyesus said in a statement.
There are approved vaccines to prevent MPOX, but there are no drugs indicated to treat the disease. Tecovirimat was approved by the U.S. Food and Drug Administration in 2018. to treat smallpox, a related virus, and ongoing clinical trials of the drug were started in 2022 to treat mpox during the global outbreak. The drug is also available in the U.S. for mpox under an expanded access program that allows a doctor to treat a patient with research drug outside a clinical trial. In the UK and Europe, TPOXX has been approved for operate in mpox in exceptional circumstances without comprehensive data on its effectiveness.
In the study in the Democratic Republic of Congo, nearly 600 participants were randomly assigned to receive tecovirimat or placebo and were admitted to hospital for at least 14 days, where they were closely monitored. All participants received supportive care, which included nutrition, hydration, and treatment for any secondary infections. Although the drug appeared unthreatening, it was no better at healing patients’ lesions than placebo.
Remarkably, mortality was lower, and patients’ lesions healed faster than expected, regardless of whether they received tecovirimat or placebo. The study’s overall mortality rate of 1.7 percent among participants, regardless of whether they received the drug or not, was significantly lower than the MPox mortality rate of 3.6 percent or more reported in all cases in the Democratic Republic of Congo.