During the 2022 Mpox outbreak in New York City, a disproportionate number of those infected also lived with HIV. Tecovirimat (TPOXX) was the agent most used for treatment.
SIGA Technologies, Inc. originally developed this medication and was initially approved for the treatment of smallpox,
As of May 2, 2023, no published data compared Mpox virus (MPXV) treatment outcomes between patients with HIV infection and those without.
In this preliminary study, the clinical presentation and treatment outcomes in 154 patients with confirmed MPXV infection were treated with tecovirimat with and without HIV.
This study found no significant differences in clinical presentation or treatment outcomes between the two study groups.
As in other U.S. data, patients in this report were almost exclusively men. However, people with HIV infection were slightly older (mean, 39 vs. 32 years).
They were more likely than HIV-negative patients to identify as Black or Hispanic, which reflects both the disproportionate burden of HIV in these groups and the underlying demographics of patients receiving HIV care at Columbia University Medical Center and Weill Cornell Medical Center.
In this study, people with HIV (PWH) were likelier to report skin lesions, fever, and diarrhea on day 1 of illness.
In contrast, those without HIV were more likely to experience a prodrome and to develop additional symptoms or examination findings, including lymphadenopathy.
This discrepancy in lymphadenopathy was also noted in a large U.S. case series (10) but not in a similar German report (9).
The significance of this difference is unclear, but it may contribute to diagnostic uncertainty in PWH between MPXV and herpesviruses, such as herpes simplex virus and varicella-zoster virus, which do not typically present with enlarged lymph nodes.
Prior reports suggest that PWH are hospitalized with mpox at higher rates than HIV-negative persons.
We found no apparent differences in hospitalization rate, but this may have been affected by the very low proportion of patients in our cohort with a CD4 count less than 0.20 × 109 cells/L.
Additional study is needed comparing disease severity and therapeutic decision-making between PWH with low CD4 cell counts and others with mpox.
As in other reports, tecovirimat was well tolerated in this case series, with no serious adverse events attributed to the medication.
Some symptoms noted as adverse effects (such as fatigue or malaise) are also symptoms of an infection; therefore, attribution to medication alone is difficult.
Finally, persons in this series had similar treatment outcomes regardless of HIV status. As in other reports, almost all patients had complete resolution of pain by the end of treatment.
Additional studies are needed to show the effect of tecovirimat on disease progression and to track the timeline of symptom resolution more closely, wrote these researchers.
Although it remains unclear how the incidence and demographic features of the current mpox outbreak will develop going forward, the present scenario requires a better understanding of both disease and treatment in those who bear the most significant disease burden to date—primarily MSM and PWH.
Tecovirimat is a promising treatment whose efficacy will hopefully be borne out in future rigorous studies.
Regardless, we believe that our study adds substantially to the body of knowledge about patient experience with tecovirimat therapy and can help inform patient counseling during treatment initiation, concluded these researchers.
Notes:
This study had several limitations, such as no control group of patients infected with MPXV who did not receive tecovirimat.
No studies to date compare treatment outcomes of PWH versus those of HIV-negative persons. To what degree HIV acts as an independent risk factor for mpox acquisition is unclear. However, emerging data suggest that uncontrolled HIV infection is a risk factor for developing severe disease.
And a recent report from the U.S. Centers for Disease Control and Prevention noted higher hospitalization rates among persons infected with HIV and MPXV, but data on determinants of the decision for hospitalization were not reported.
This study did not disclose the person's Mpox vaccination status.
The National Institutes of Health funded this study but had no role in the study design; collection, analysis, or interpretation of data; writing of the report; or the decision to submit the manuscript for publication.
Additional Mpox research is posted by Precision Vaccinations.
