CROI 2025: Tecovirimat has no benefit against mpox in STOMP study
18 March 2025. Related: Early access, Conference reports, mpox, CROI 32 San Francisco 2025.
Simon Collins, HIV i-Base
Last year two randomised controlled studies were stopped early for futility after showing no benefit as a treatment against mpox, but only limited details were released by press release.
Several months later, details of the NIH PALM007 study conducted at two sites in the DRC were presented at IDWeek and were reported in HTB. [1]
Full results from the US-based international STOMP study were presented at CROI 2025.
STOMP randomised 344 participants with confirmed mpox clade 2 (2:1) to a 14-day course of tecovirimat or placebo. Nearly all were cisgender men (3% transgender), with one-third living with HIV and one-third with severe pain. Median number of lesions was 8 (range: 4 to 18).
There were no differences in clinical resolution at day 29: 83% vs 84%, p=0.89, or mean (SD) pain score reduction (3.2 [2.1] vs 3.1 [2.0]), both in the active vs placebo groups respectively.
There were also no differences in various sub-population analyses including early treatment and severity of pain.
Although further analyses are still ongoing, the presentation concluded with the urgency of finding effective treatments for mpox.
References
- HTB. Detailed results from PALM007 study: no clinical impact of tecovirimat against mpox clade 1. HTB (January 2025).
i-base.info/htb/50006 - Wilkin T et al for the ACTG A5418 Study Team. Tecovirimat Is Safe but Not Efficacious in People With Clade II Mpox. CROI 2025. Oral abstract 200.
www.croiconference.org/abstract/3822-2025 (abstract)
watch.croiwebcasts.org/2025croi/ap/54367 (webcast for delegates)