Erasca faces a securities class action after its stock fell 48%, erasing $2.8 billion in market value, following a patient death and patent infringement allegations from Revolution Medicines over its lead drug candidate ERAS-0015.
Erasca faces a securities class action after its stock fell 48%, erasing $2.8 billion in market value, following a patient death and patent infringement allegations from Revolution Medicines over its lead drug candidate ERAS-0015.

Erasca Inc. faces a securities class action after its stock plunged 48%, wiping out $2.8 billion in market value, following disclosures of a patient death and patent infringement allegations from Revolution Medicines.
"The complaint alleges Erasca made materially false or misleading statements regarding ERAS-0015's preclinical superiority over RMC-6236 while concealing patent infringement risk," Joseph E. Levi, partner at Levi & Korsinsky, said in a statement.
The class period runs from Jan. 14, 2025, to April 26, 2026. On April 27, Erasca disclosed in two separate filings that Revolution Medicines had sent a letter alleging patent infringement and trade secret misappropriation, and that a patient treated with ERAS-0015 had died. Shares fell from $21.49 to $19.15 after the first disclosure before market open, then opened at $10.51 the next trading day and closed at $9.90 — a cumulative decline of about 54%.
The lawsuit centers on Erasca's lead pipeline candidate, ERAS-0015, an investigational pan-RAS molecular glue for RAS-mutant solid tumors. The company had drawn comparisons between its drug and Revolution Medicines' RMC-6236, claiming ERAS-0015 demonstrated 8-to-21-fold higher binding affinity to cyclophilin A and comparable efficacy at roughly one-tenth the dose. Revolution Medicines contends Erasca obtained its trade secrets through third-party misappropriation.
Erasca first publicly compared ERAS-0015 to RMC-6236 at the J.P. Morgan Healthcare Conference in January 2025, stating it had identified "no patentability roadblocks." The company repeated and expanded those comparisons in its 2024 annual report filed in March 2025 and again in a January 2026 presentation that included six slides directly benchmarking the two drugs. That presentation coincided with a $258.8 million stock offering that closed Jan. 23, 2026.
The lead plaintiff deadline is Aug. 10, 2026. Investors who purchased Erasca shares during the class period may seek to recover damages. Hagens Berman and Levi & Korsinsky are among the firms investigating potential securities law violations.
The decline puts Erasca shares at their lowest since the company went public, testing investor confidence in its pipeline. The next catalyst is the lead plaintiff deadline on Aug. 10, which will determine whether the class action proceeds and how the company navigates both the patent dispute and the clinical safety questions surrounding ERAS-0015.
This article is for informational purposes only and does not constitute investment advice.