In a recent commentary published within the Annals of Internal Medicine, researchers performed a retrospective cohort study amongst patients treated with tecovirimat for human immunodeficiency virus (HIV)-infected mpox virus (MPXV) patients between June and August 2022 in Recent York City, United States of America (USA).

Study: Tecovirimat Treatment of People With HIV Throughout the 2022 Mpox Outbreak. Image Credit: Dotted Yeti / Shutterstock

Background

Tecovirimat, originally developed and approved for smallpox treatment, has been widely utilized in the present MPXV outbreak. Reports have confirmed that tecovirimat use resolves >90% of MPXV disease symptoms and is well-tolerated, leading to only mild hostile effects.

The scientific literature on safety and clinical outcomes of tecovirimat treatment amongst MPXV cases is increasing. Nonetheless, there may be a shortage of studies comparing the tecovirimat treatment outcomes for people having MPXV infection while living with HIV [PWH] and without HIV.

Concerning the study

In the current study, researchers recruited all patients who initiated treatment with tecovirimat based on the Centers for Disease Control and Prevention (CDC) eligibility guidelines under the EA-IND protocol at NewYork-Presbyterian’s Weill Cornell or Columbia University Medical Centers between 20 June and 29 August 2022.

The study participants had confirmed MPXV infection and accomplished at the very least two follow-up visits within the inpatient, outpatient, and telehealth settings.

The team examined safety outcomes and the looks of recent lesions at 48 hours amongst participants who accomplished at the very least one follow-up visit. As well as, they monitored clinical outcomes, including resolution of pain and protracted disease symptoms by the tip of the treatment amongst those completing at the very least one follow-up visit after treatment completion.

In total, 196 patients initiated treatment with tecovirimat, of which 154 had confirmed MPXV infection, and 72 and 82 were PWH and HIV-negative, respectively. The remaining 134 individuals accomplished at the very least one follow-up visit, and 88 accomplished a follow-up visit after the completion of treatment. Strikingly, all patients on this cohort study were men.

Results

The study authors observed no substantial variations in clinical presentation or treatment outcomes between the 2 groups comprising PWH and HIV-negative patients infected with MPXV and receiving tecovirimat treatment. On this study, most PWH were older (mean age, 39 vs. 32 years) and self-identified as Black or Hispanic. Of all, 14 HIV-positive individuals had a viral load >1000 copies/mL, while 70% of HIV-negative individuals took HIV PrEP at the primary study visit.

PWH more likely reported skin lesions, fever, and diarrhea upon illness onset. Conversely, HIV-negative patients experienced a prodrome and developed additional symptoms, including lymphadenopathy, much later. Though the importance of this discrepancy is unclear, it could be resulting in diagnostic ambiguity in PWH having MPXV or herpes simplex virus (HSV), which don’t manifest as enlarged lymph nodes. Strikingly, each group patients similarly contracted severe mpox disease, and there have been no marked inter-group differences other than treatment eligibility criteria for HIV infection.

While previous reports have suggested that more PWH than HIV-negative patients sought hospitalization for mpox, on this study, the authors observed no apparent differences of their hospitalization rates, likely as a result of a low proportion of patients on this cohort with a CD4 count of <0.20 × 109 cells/L. More work could confirm the necessity for therapeutic decision-making when comparing mpox infection severity between PWH with low CD4 counts and other cases.

Importantly, consistent with prior reports, tecovirimat treatment was well tolerated and fetched no serious hostile events on this case series. The authors noted fatigue or malaise in some cases, that are also mpox infection symptoms; and, due to this fact, can’t be attributed entirely to tecovirimat medication.

Finally, treatment outcomes after tecovirimat therapy were encouraging whatever the HIV status of patients. The pain was resolved for nearly all patients by the point treatment ended. Similarly, skin lesions that developed >48 hours after treatment initiation or persevered after treatment completion resolved amongst PWH and HIV-negative patients. In actual fact, all persistent symptoms healed by the point of treatment completion.

Future studies could confirm whether shorter times to treatment initiation would have altered treatment outcomes for tecovirimat. Moreover, studies should exhibit the effect of tecovirimat on the progression to severe disease and symptom resolution timelines for PWH and HIV-negative patients. Notably, PWH began tecovirimat therapy sooner, and HIV-negative patients were taking PrEP.

Conclusions

The findings of the Study of Tecovirimat for Human Mpox Virus (STOMP) trial evaluating the efficacy of tecovirimat against MPXV usually are not yet available. Up to now, only case series have demonstrated the efficacy and safety of tecovirimat, the antiviral agent most used for MPXV treatment.

The present preliminary study is the primary of its kind to check tecovirimat treatment outcomes between HIV patients and people without HIV infection. It fills the knowledge gap about patient experience with tecovirimat treatment and will help counsel patients searching for mpox treatment.

Since MSM and PWH currently share a disproportionate and the best burden of MPXV disease, a greater understanding of each disease symptoms and treatment outcomes in these people is crucial. Despite the shortage of clarity on how the present mpox outbreak will develop, future studies will fetch evidence favoring tecovirimat use as a promising therapy for MPXV infections.

Journal reference:

• Tecovirimat Treatment of People With HIV Throughout the 2022 Mpox Outbreak, Jacob McLean, Kate Stoeckle, Simian Huang, Jonathan Berardi, Brett Gray, ANP, Marshall J. Glesby, Jason Zucker, Annals of Internal Medicine 2023, DOI: https://doi.org/10.7326/M22-3132, https://www.acpjournals.org/doi/10.7326/M22-3132