As the mpox outbreak continues to ravage Central Africa, a clinical trial in the Democratic Republic of Congo (DRC) has found that the antiviral drug tecovirimat, also known as TPOXX, is no more effective than a placebo at clearing mpox lesions. This disappointing result comes as the WHO has declared the mpox situation in Central Africa a global health emergency.
The trial, sponsored by the US National Institute of Allergy and Infectious Diseases, enrolled nearly 600 participants with the clade I type of mpox virus, which is endemic to Central Africa and causes more severe disease.
Participants were randomly assigned to receive either tecovirimat or a placebo and were hospitalised for at least 14 days, receiving supportive care including nutrition, hydration, and treatment for secondary infections. While tecovirimat was found to be safe, it did not reduce the duration of lesions compared to placebo.
Notably, mortality among study participants was only 1.7%, much lower than the 3.6% mortality typically seen for mpox in the DRC. This suggests that providing high-quality supportive care can significantly improve outcomes for mpox patients.
However, the trial results still represent a setback, as tecovirimat is the only antiviral drug approved for mpox treatment in some countries.
The mpox outbreak in Central Africa has been marked by several concerning developments, including the spread of the virus to neighbouring countries and the first evidence of sexual transmission of the clade I virus. Since the beginning of 2023, 13 African countries have reported over 20,000 confirmed or suspected mpox cases and nearly 600 deaths.
In response, the WHO has launched a strategic plan to control the outbreak, which focuses on boosting surveillance, testing, and vaccine access. Nonetheless, vaccine supplies remain limited in Africa, with no doses currently available in the DRC despite the country’s urgent need.