New York-based Siren bought 2,486,997 shares of Erasca in the first quarter; the estimated transaction value was $29.39 million based on average first-quarter 2026 prices.
Meanwhile, the quarter-end position value rose by $149.35 million, reflecting both additional shares and price movement.
The transaction represents a 0.81% change in 13F reportable assets under management (AUM).
The quarter-end holding stood at 11,244,246 shares valued at $181.93 million.
New York-based Siren disclosed a purchase of 2,486,997 Erasca (NASDAQ:ERAS) shares in its May 14, 2026, SEC filing, an estimated $29.39 million trade based on quarterly average pricing.
According to a May 14, 2026, SEC filing, Siren added 2,486,997 shares of Erasca (NASDAQ:ERAS) to its portfolio. The estimated transaction value was $29.39 million, based on the average closing price during the first quarter of 2026. The quarter-end value of the Erasca position increased by $149.35 million, a figure that includes both the impact of the additional shares and underlying price appreciation.
| Metric | Value |
|---|---|
| Price (as of market close 2026-05-13) | $10.46 |
| Market Capitalization | $3.17 billion |
| One-Year Price Change | 700% |
Erasca, Inc. is a biotechnology company specializing in the development of therapies for cancers driven by the RAS/MAPK pathway. Erasca, Inc. develops targeted oncology assets focused on RAS/MAPK pathway-driven cancers, with clinical-stage candidates addressing a range of difficult-to-treat tumors. Erasca is advancing clinical-stage candidates targeting key cancer pathways for patients with difficult-to-treat tumors.
It seems like Siren believes Erasca’s explosive rally may still be early in the company’s broader clinical story, and there’s reason to understand why. The company just this week reported encouraging early data for ERAS-0015, including “robust” responses in KRAS G12X lung and pancreatic cancers alongside what management described as generally favorable tolerability. Erasca also said dose escalation and monotherapy expansion milestones were completed ahead of schedule, with additional data expected in the first half of 2027.
Importantly, the company appears well-funded enough to pursue aggressive development plans. Erasca finished the first quarter with roughly $409 million in cash and marketable securities after completing a $258.8 million upsized financing in January. Management expects that capital will fund operations into the second half of 2028.
For long-term investors, the opportunity here centers on whether ERAS-0015 can truly emerge as a backbone therapy for RAS-driven cancers, one of oncology’s largest unmet markets. The stock’s massive run reflects rising optimism, but like most clinical-stage biotech stories, future data will ultimately matter far more than momentum.
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Jonathan Ponciano has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends BeOne Medicines Ag. The Motley Fool recommends Kymera Therapeutics. The Motley Fool has a disclosure policy.