Preliminary Fourth Quarter and Full Year 2024 Financial Results* and Recent Business Highlights

• Preliminary fourth quarter and full-year 2024 U.S. net product revenue for OGSIVEO were $61.5 million and $172.0 million, respectively.
• As of December 31, 2024, total preliminary cash, cash equivalents, and marketable securities was $461.9 million. SpringWorks expects its cash position to fund operations through profitability, which the Company anticipates achieving in the first half of 2026.
• Presented long-term follow-up data from the Phase 3 DeFi trial of nirogacestat in adults with progressing desmoid tumors in the fourth quarter of 2024. These results showed that longer-term treatment with nirogacestat (median duration of treatment: 34 months) was associated with further reductions in tumor size, increase in objective response rate with additional partial responses and complete responses, sustained improvements in desmoid tumor symptoms including pain, and a consistent safety profile.
• Obtained an exclusive, global license from Rappta Therapeutics Oy for a first-in-class molecular glue of specific Protein Phosphatase 2A (PP2A) complexes. PP2A mutations represent a class of targetable oncogenic drivers in molecularly defined subsets of uterine cancer patients with high unmet need. In preclinical models of PP2A mutant uterine cancer, SW-3431 (formerly RPT04402) showed rapid, deep and durable tumor regressions as a monotherapy. In exchange for the license, Rappta received a $13 million upfront payment and is eligible to receive further clinical, regulatory and commercial milestone payments, and tiered single digit royalties on net sales.