Erasca shares are up about 5% in Friday trading, extending a volatile stretch for the oncology developer as investors trade ahead of the company’s expected first-half 2026 Phase 1 monotherapy data for ERAS-0015, its pan-RAS molecular glue. With no fresh company announcement visible this week, the move looks primarily sentiment- and positioning-driven, with options activity and catalyst anticipation keeping the stock in play.

Erasca has guided that Phase 1 monotherapy data for ERAS-0015 is expected in the first half of 2026, and it has previously highlighted encouraging early activity during dose escalation, including ongoing partial responses across multiple RAS-mutant tumors with favorable safety/tolerability and pharmacokinetics. The company also emphasized a strengthened balance sheet and runway into the second half of 2028 following its January financing, which can reduce near-term funding overhang as the market focuses on clinical readouts.

Earlier this week, call-option volume in ERAS was flagged as unusually elevated versus typical levels, a dynamic that can amplify day-to-day price swings as traders chase momentum or hedge short exposure. With the stock having recently traded near highs, incremental buying interest can translate quickly into outsized percentage moves, particularly in smaller-float biotech names that are heavily catalyst-driven.

The next clear inflection point remains Erasca’s Phase 1 monotherapy update for ERAS-0015 (still expected by June 30, 2026, based on the company’s first-half guidance), with investors likely focused on response durability, breadth across RAS mutations, and dose/safety details. Beyond that, Erasca has guided for initial Phase 1 monotherapy data for ERAS-4001 in the second half of 2026, setting up a second catalyst later this year.