SELLAS Life Sciences Reports Second Quarter 2025 Financial Results and Provides Corporate Update

- Positive IDMC Recommendation to Continue Pivotal Phase 3 REGAL Trial of Galinpepimut-S (GPS) in AML Without Modification; Final Analysis Anticipated by Year-end 2025 – - Reported Positive Phase 2 Results of SLS009 in Relapsed/Refractory (r/r) Acute Myeloid Leukemia (AML) with Trial Meeting All Primary Endpoints; Full Data Presentation Expected Later This Year - - Alignment with FDA to Advance SLS009 in a First-Line AML Trial with Enrollment Anticipated by Q1 2026 - - $25.3 million in Cash and Cash Equivalents as of June 30, 2025; Additional $4.0 million Proceeds Received in July 2025 for Warrant Exercises -