Erasca Faces Securities Lawsuit After Patent Claims and Patient Death

The lawsuit, filed by Hagens Berman, targets the period between January 14, 2025, and April 26, 2026. Plaintiffs contend that Erasca improperly compared its 40-milligram ERAS-0015 dose to a competitor’s 400-milligram treatment, bolstering a "best-in-class" narrative that lacked a reasonable basis. These claims were further undermined by legal challenges from Revolution Medicines, which accused Erasca of obtaining trade secrets through third-party misappropriation.

Market confidence evaporated on April 27, 2026, when the company disclosed the patent dispute alongside the death of a patient who had received the treatment one month prior. The dual revelations wiped $2.8 billion from the company's market capitalization in a single session. Reed Kathrein, a partner at Hagens Berman, stated that the firm is investigating whether the company intentionally obscured both the safety profile of its cancer treatment and the fragility of its competitive moat.