Tecovirimat Likely Most Effective Antiviral Treatment Option for Monkeypox Infection

Results of a systematic review published in the International Journal of Infectious Diseases indicate tecovirimat is the most beneficial antiviral treatment option for patients with monkeypox virus infection.

Researchers at institutions in India searched publication databases through November 2022 for studies that compared the safety and efficacy of various antivirals for the treatment of monkeypox infection. A total of 18 uncontrolled, observational studies were included in this review.

The study population comprised 71 patients, of whom most (81.7%) were men, and the majority (66.2%) resided in the United States. Outcomes of patients with the infection were generally favorable, with 83.1% reporting complete symptom resolution.

Five medications have been used for the treatment of monkeypox infection as of this review, including tecovirimat, cidofovir, brincidofovir, trifluridine, and vaccinia immune globulin intravenous. Tecovirimat was the most widely used medication across all included studies.

Overall, symptom improvement occurred within days among patients following tecovirimat initiation. Improvements were observed in patients who experienced burning sensations or fever, as well as among those with lesions over the facial and oral regions or the trunk and extremities. Favorable outcomes were observed among patients who received tecovirimat following treatment with either vancomycin, piperacillin/tazobactam, dexamethasone, acyclovir, fluconazole, or penicillin. Outcomes of tecovirimat also were favorable in 1 patient with HIV infection.

Complications associated with tecovirimat were uncommon, such as fatigue, headache, and nausea. During tecovirmat use, 3 patients experienced transient increases in hepatic enzymes, and one patient had reported loose stools following each dose. Of note, 1 death occurred, though it was determined to be unrelated to tecovirimat treatment.

Cidofovir use for monkeypox infection was reported in 4 studies. Treatment with cidofovir was associated with favorable outcomes in 1 patient, and 1 patient had severe ocular involvement in which evolving lesions were observed as of the most recent follow-up visit. No adverse events associated with cidofovir were reported.

Among 3 patients who received brincidofovir, all experienced increases in hepatic enzymes and treatment was prematurely discontinued. These patients also reported conjunctivitis, lower extremity abscess, and neuropsychiatric symptoms.

Trifluridine eye drops were administered to 4 patients with ocular monkeypox infection. Of these patients, 3 recovered and 1 had fluctuating symptoms with marked vision impairment.

The major limitation of this review was the quality of available data.

According to the researchers, “The promising results seen with Tecovirimat should be investigated further in well-designed research.”

Reference

Shamim MA, Padhi BK, Satapathy P, et al. The use of antivirals in the treatment of human monkeypox outbreaks: a systematic review. Int J Infect Dis. 2022;127:150-161. doi:10.1016/j.ijid.2022.11.040