Early use of mpox antiviral shows promise among people with HIV: Study

New York : Using antiviral tecovirimat (Tpoxx) within 7 days of mpox symptom onset is associated with lower rates of mpox disease progression among people with HIV (PWH), according to a study.

The cohort study, published in JAMA Internal Medicine, was based on outcomes seen among 112 PWH diagnosed as having mpox from June 1, to October 7, 2022.

A total of 56 people were classified as cases and received tecovirimat within 7 days of mpox symptom onset (early tecovirimat group), and 56 were controls who were either treated later or did not receive tecovirimat at all (late or no tecovirimat group).

In both the case and control groups, 96 per cent of participants were cisgender men, and more than 80 per cent were Black. The average age was 35 and 36, respectively among cases and controls. The main outcome was progression of disease after 7 days.

Mpox disease progression occurred in 3 PWH (5.4 per cent) in the early tecovirimat group and in 15 PWH (26.8 per cent) in the late or no tecovirimat group.

"Results of this cohort study support starting tecovirimat in all PWH as soon as an mpox diagnosis is suspected," said Bruce Aldred, from Emory University’s School of Medicine in Georgia, in the paper. "Additional research is warranted to confirm these findings," he added.

Although the findings are encouraging, a blanket recommendation to give Tpoxx to all PWH as soon as mpox is suspected may be premature given the limitations of tecovirimat availability, experts argued in an accompanying commentary, CIDRAP reported.

"The study shows the efficacy of Tpoxx, but ignores that most PWH in the US are not eligible for Tpoxx use based on current CDC guidelines, which would not include a PWH with undetectable viral loads," said experts from the universities of Columbia, North Carolina; and Cornell.

The CDC recommendations currently include only PWH who have advanced or poorly controlled infection, as well as immunocompromised patients, children, and pregnant or breastfeeding women.

"Besides the practical issue that there is no clear path to obtaining tecovirimat treatment for all patients with HIV, there are reasons to favour limiting its use to those who would potentially benefit the most," Jason Zucker, from Columbia University. "First, there is concern that broad use of tecovirimat could result in resistant virus. Second, mpox does not appear to be a severe disease in healthy persons with HIV."