Early use of tecovirimat, known as Tpoxx, an antiviral used in mpox infections, leads to a subjective improvement in symptoms, according to a new study in Open Forum Infectious Diseases.
The small study was based on outcomes seen in mpox patients identified in King County, Washington, from May to October 2022. Of 465 individuals diagnosed with mpox during the study period, 115 (25%) participated in this study.
Outcomes were compared among those who started taking tecovirimat 5 or fewer days after symptom onset and those who began 6 to 28 days after symptom onset.
A subjective sense of earlier resolution in symptoms was seen among those who started the antiviral 5 days or less after first becoming symptomatic, but only if the patient experienced severe symptoms, defined as proctitis, rectal bleeding, and severe pain.
Given the potential benefit of early treatment in severe disease, providers could consider offering tecovirimat prior to laboratory-confirmation.
In a multivariable analysis, early tecovirimat was associated with shorter time to symptom improvement (-5.5 days) among participants with severe illness but not among those with non-severe illness (1 days). Early tecovirimat was not associated with faster illness resolution, regardless of severity, the authors wrote.
The researchers called for a randomized controlled trial to clarify the study results and said the present findings could be due to small numbers in stratified groups and limited power or from tecovirimat slowing progression, but not hastening, resolution of mpox.
"Given the potential benefit of early treatment in severe disease, providers could consider offering tecovirimat prior to laboratory-confirmation, particularly as data suggests that well-trained sexual health clinic providers can accurately diagnose mpox prior to laboratory confirmation," the authors wrote.