BBP-398

Erasca, Inc. (USA) announced on April 27, 2026, via a US Securities and Exchange Commission Form 8-K filing, that Revolution Medicines, Inc. (RevMed, USA) had transmitted a letter alleging that ERAS-0015, Erasca’s pan-RAS molecular glue, infringes RevMed’s US Patent No. 12,409,225. The dispute centers on the molecular glue class of RAS-targeting agents, where compounds are designed to suppress oncogenic RAS signaling by stabilizing inhibitory protein-protein interactions rather than occupying a conventional active site, a mechanistic distinction that has drawn substantial competitive interest across the oncology sector. RevMed’s letter, received by Erasca on April 24, 2026, asserted three distinct claims: that ERAS-0015 is substantially equivalent to compositions claimed in the ‘225 Patent and therefore infringes it under the doctrine of equivalents; that a third party misappropriated RevMed’s alleged trade secrets in connection with a patent relating to ERAS-0015, rendering Erasca liable as a licensee under applicable trade secret law; and that Erasca made improper comparative statements in public disclosures contrasting preclinical data for ERAS-0015 and RevMed’s own RMC-6236. RevMed demanded that Erasca immediately cease all making, using, offering for sale, selling, and importation of ERAS-0015 in the United States for any purpose not protected by the Hatch-Waxman safe harbor, and that Erasca discontinue comparative statements RevMed characterized as deceptive. Erasca stated it believes the assertions are without merit and intends to contest the allegations vigorously. The ‘225 Patent, based on the “compositions claimed” language cited in the 8-K, appears to cover composition-of-matter claims directed at pan-RAS molecular glue compounds. The full claim text was not disclosed in the filing, and specific patent term or expiry data were not provided. The doctrine-of-equivalents theory advanced by RevMed suggests that ERAS-0015 may not be literally identical to the claimed compositions but is alleged to be functionally or structurally analogous within the scope of the granted claims. ERAS-0015 is currently in a Phase I first-in-human study designated AURORAS-1 (NCT06983743), evaluating safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity in patients with advanced or metastatic RAS-mutant solid tumors. On the same day the 8-K was filed, April 27, 2026, Erasca announced a conference call and webcast to present preliminary Phase I dose-escalation data from that study. Earlier company disclosures from March 2026 referenced favorable safety and tolerability observations, linear pharmacokinetics, and confirmed and unconfirmed partial responses in the dose-escalation cohort. Those characterizations originated from company press releases rather than peer-reviewed publications, and Erasca has described the data as preliminary. Specific clinical results including patient counts, response duration, and adjudicated efficacy outcomes have not been disclosed in the materials available from this filing. The dispute between Erasca and RevMed reflects the degree of competition that has emerged around pan-RAS and RAS-ON inhibition strategies, a class that has moved from conceptual interest to active clinical development over the past several years. RAS mutations are present across a broad range of solid tumor histologies, and agents capable of suppressing multiple RAS isoforms or mutant variants have attracted attention from multiple development organizations. RevMed’s own RMC-6236 is a RAS-ON multi-selective inhibitor, meaning it targets the active GTP-bound state of RAS rather than a specific mutant allele. RMC-6236 is being evaluated in a Phase I/II program (NCT05379985) in patients with RAS-mutant solid tumors including pancreatic ductal adenocarcinoma, non-small cell lung cancer, and colorectal cancer. RevMed’s letter to Erasca explicitly referenced comparative preclinical disclosures involving RMC-6236 and ERAS-0015, indicating that RevMed views the two programs as operating in overlapping mechanistic and commercial territory. A second program from RevMed, RMC-6291, targets KRAS G12C specifically in the active state and is in Phase I evaluation (NCT05462717). Within the broader molecular glue and pan-RAS space, Navire Pharma (USA) has advanced BBP-398, a SHP2 inhibitor that functions upstream of RAS to reduce RAS activation, in Phase I/II combination studies (NCT04528836). While SHP2 inhibition is mechanistically distinct from a direct RAS molecular glue, both strategies aim to suppress RAS pathway output across tumor genotypes rather than targeting a single mutant allele. Mirati Therapeutics, now part of Bristol Myers Squibb (USA), developed adagrasib (KRAS G12C-specific covalent inhibitor) as a mutation-selective agent; its US FDA approval in KRAS G12C-mutant non-small cell lung cancer and colorectal cancer established a regulatory precedent for RAS-directed therapy but does not address the broader RAS-mutant population that pan-RAS strategies are designed to reach. The patent dispute introduced by RevMed’s letter adds a legal dimension to an already competitive development environment. Erasca has not indicated any intention to pause the AURORAS-1 trial or alter its development plans for ERAS-0015 in response to the letter. The Hatch-Waxman safe harbor referenced in RevMed’s demand would, if applicable, protect clinical research activities from infringement liability under US law. Resolution of the underlying patent and trade secret claims would require either negotiated settlement or litigation proceedings, neither of which has been initiated as of the filing date. This article was generated with AI assistance and reviewed and edited by the AllSci editorial team Explore more at AllSci News: https://allsci.com/news/ Your email address will not be published. Required fields are marked * Comment * Name * Email * Website