Abemaciclib (CDK4/6) Hits 68% PFS6 in Recurrent Grade 2/3 Meningioma

Abemaciclib is an oral CDK4/6 inhibitor; in a multicenter basket trial (NCT03220646), an expanded cohort of recurrent meningioma (mostly grade 2–3; n=22) received 200 mg twice daily on 28-day cycles. The meningioma cohort achieved median PFS 15 months (95% CI 6.5–NR), median OS 32.9 months (95% CI 10.7–NR), and 6-month PFS 68.2% (95% CI 51.3–90.7%); disease stabilization occurred in 73% (16/22) with 0% objective responses. The PFS6 exceeds the RANO activity benchmark for grade 2–3 meningioma (49%) and compares favorably with systemic comparators such as pembrolizumab (PFS6 48%, mPFS 7.6 mo) and sunitinib (PFS6 42%, mPFS 5.2 mo), though safety details were not provided in the abstract and can be assumed to be those typical of abemaciclib (diarrhea, often during the first month of treatment, low blood cell counts, fatigue, and nausea).