ASCO 2026: SARC041 Plenary — Abemaciclib Reduces Liposarcoma Progression Risk by 62%, First Positive Phase 3 Result Ever in Dedifferentiated Liposarcoma

The Phase 3 SARC041 trial, presented at the ASCO 2026 Annual Meeting in Chicago, delivered the first ever positive randomized controlled trial result in dedifferentiated liposarcoma (DDLPS) — a rare and historically treatment-resistant soft tissue sarcoma with a 5-year survival rate under 20% in advanced disease. The trial evaluated abemaciclib (Verzenio), an oral CDK4/6 inhibitor originally approved for breast cancer, in patients with advanced DDLPS — a tumor type characterized by CDK4 gene amplification in approximately 90% of cases, providing the mechanistic rationale for this study. Lead investigator Dr. Mark A. Dickson (Memorial Sloan Kettering Cancer Center) presented data showing abemaciclib achieved a median progression-free survival of 9.67 months versus 1.52 months with placebo (HR 0.38, 90% CI: 0.25–0.59; p<0.001) — a 62% reduction in the risk of disease progression or death. Six-month PFS rates were 60% (abemaciclib) vs. 22% (placebo); 12-month PFS 39% vs. 13%. The benefit was observed consistently across CDK4-amplified and non-CDK4-amplified subgroups, though CDK4-amplified patients showed numerically stronger benefit. The safety profile was consistent with the known abemaciclib profile including neutropenia, diarrhea, and fatigue. This is a landmark result for the DDLPS community, which has had essentially no approved targeted therapies. Regulatory submissions to FDA and EMA are anticipated.