Erasca Cuts 18% and Replaces KRAS Program with New Anti-Tumor Options

Erasca, a San Diego-based biotechnology firm specializing in cancer treatments targeting the RAS/MAPK pathway, has announced a significant restructuring of its operations. This includes acquiring new assets, reshuffling its drug development pipeline, and reducing its workforce by 18%. The company's strategic moves aim to bolster its portfolio while making room for promising new treatments.

Erasca is investing $22.5 million upfront to enhance its pipeline with preclinical KRAS and molecular glue assets. Specifically, the company is paying $10 million to Medshine Discovery for the global rights to the KRAS inhibitor ERAS-4001. Described as having the potential to offer a better therapeutic window than existing RAS inhibitors, ERAS-4001 also aims to prevent resistance mediated by KRAS wildtype. Should the drug reach the market, Medshine stands to receive up to $160 million in milestone payments and a low single-digit percentage of royalties.

To accommodate ERAS-4001, Erasca has decided to terminate its internal pan-KRAS program. This program had already been scaled back a year ago due to the increasingly competitive landscape, resulting in the shelving of a KRAS G12C inhibitor despite its potential.

In another deal announced recently, Erasca is paying $12.5 million to Joyo Pharmatech for the ex-China rights to ERAS-0015, a pan-RAS molecular glue now in human trials. The candidate has shown promising potency and favorable pharmacokinetic properties in multiple animal species. Joyo could receive up to $176.5 million in milestone payments as part of the agreement.

Erasca's CEO, Jonathan Lim, M.D., expressed enthusiasm for the new additions to the company's pipeline. He highlighted the long-term potential of combining ERAS-0015 and ERAS-4001 to shut down MAPK signaling in patients with RAS mutations.

To make room for these new assets, Erasca is deprioritizing other programs, including ERAS-007, an ERK inhibitor previously in a phase 1b trial for BRAF-mutant colorectal cancer. The company cited insufficient clinical efficacy data as the reason for halting further evaluation of this candidate.

Additionally, Erasca is re-evaluating its approach to ERAS-801, an EGFR inhibitor for recurrent glioblastoma. The company plans to focus its internal resources on its pan-RAF inhibitor naporafenib, which is set to enter a phase 3 melanoma trial soon. As a result, the advancement of ERAS-801 may continue through select investigator-sponsored trials.

These strategic changes will result in an 18% reduction in Erasca's workforce, primarily affecting roles in drug discovery and the deprioritized programs. The company has committed to provide comprehensive severance packages and career transition services to those impacted.

Jonathan Lim explained that the decision to reshape the pipeline and reduce staff was challenging but necessary. By focusing resources on the most promising programs, Erasca aims to maximize its impact on patient outcomes. The company remains dedicated to advancing treatments with the highest likelihood of success, ensuring that its streamlined portfolio can deliver significant benefits to those suffering from RAS-driven cancers.