Abemaciclib Shows High Efficacy in Kaposi Sarcoma, Including HIV-Associated Cases
A phase 1/2 trial (NCT04941274) presented at the 2025 ASCO Annual Meeting found that the CDK4/6 inhibitor abemaciclib (Verzenio) was well-tolerated and demonstrated strong antitumor activity in both HIV-associated and HIV-negative Kaposi sarcoma.
Among 31 efficacy-evaluable patients, the overall response rate (ORR) was 84%. Patients with no prior therapy achieved a 90% ORR, compared with 81% among those previously treated. The median time to response was 2.5 months.
Adverse effects were consistent with known abemaciclib toxicity, most commonly diarrhea (92%), neutropenia (88%), and elevated creatinine (76%).
Researchers suggest the drug’s mechanism may relate to its inhibition of cyclin D and viral cyclin expression induced by KSHV. Validation of these findings is ongoing in a study of patients with advanced T1-stage Kaposi sarcoma.