Early Tecovirimat Treatment Shows Promise in Preventing Severe Mpox Progression in People with HIV

The progression of mpox, also known as monkeypox, disease is less likely to occur in people with HIV (PWH) who receive tecovirimat treatment as their mpox symptoms begin rather than who receive treatment later or not at all.

In a recent study published in Jama Internal Medicine, researchers belonging to different health systems in Atlanta aimed to evaluate if PWH and mpox who were treated with tecovirimat within 7 days of symptoms beginning were less likely to have mpox disease progression.

Tecovirimat is an antiviral agent made to treat smallpox but can also tackle mpox.

According to the study, the FDA approved tecovirimat for mpox treatment using expanded access for an investigational new drug. However, data showing the effectiveness of tecovirimat for treating mpox disease in humans are currently lacking.

Though there is a lack of effectiveness known, tecovirimat was widely prescribed to PWH with mpox during the 2022 mpox epidemic, especially in those with low CD4+ T-cell counts or severe clinical manifestations of mpox.

The outbreak disproportionately affected PWH as it’s more likely for this population to develop more severe mpox disease symptoms and worse clinical outcomes, especially if they have lower CD4+ T-cell counts and nonsuppressed HIV viremia.

To compare tecovirimat treatment among these groups, this cohort study included PWH diagnosed with mpox at 4 hospitals in Atlanta between June 1 and October 7, 2022.

Patients were grouped by whether they were treated with tecovirimat within 7 days of mpox symptoms beginning, if they received the drug 7 or more days after symptoms began or if they didn’t receive treatment at all.

Multivariable logistic regression models were used to identify factors associated with progression of mpox disease. The two groups were then matched 1 to 1 using propensity scores based on the identified factors, and mpox disease progression was compared.

After propensity score matching, a total of 112 PWH were included in the analysis; 56 received tecovirimat within 7 days of mpox symptoms beginning and 56 were either treated later or did not receive tecovirimat.

In addition, key factors for inclusion after the propensity score matching included age, race, HIV viral load suppression, mucosal site involvement and hospitalization on day 7.

Through logistic regression, researchers found that not having the HIV viral load under control and having the infection affect mucosal sites were strongly associated to an increased chance of having a severe case of mpox disease.

Results from the study revealed that mpox disease progression was less likely in the early tecovirimat cohort (5.4%) compared to the late or no tecovirimat cohort (26.8%).

Pairs with one person experiencing severe mpox disease progression were mainly from the late or no treatment group.

The odds ratio estimate revealed significantly higher odds of severe mpox disease progression in the late or no tecovirimat cohort.

As for the median time to mpox disease progression, it was longer in the early tecovirimat cohort than in the late or no tecovirimat cohort.

In the early tecovirimat cohort, the median time from symptoms beginning to tecovirimat initiation was 4 days.

Study authors suggest that tecovirimat treatment should be started early at the time of suspected mpox diagnosis in all PWH, especially in those with nonsuppressed HIV viremia or mucosal site involvement. Additional research is also suggested to confirm these findings.