South San Francisco-based Electra Therapeutics, Inc. (Nasdaq: ETRA), developing a signal regulatory protein (SIRP)-targeted antibody for a rare hyperinflammatory syndrome with no approved therapies, priced an upsized IPO at USD 350 million.
The offering comprises 23,333,334 shares at USD 15.00 per share, with underwriters holding a 30-day option to purchase up to an additional 3,500,000 shares. Jefferies, TD Cowen, Evercore ISI, and Cantor acted as joint book-running managers. Shares were expected to begin trading on the Nasdaq Global Select Market on September 18, 2026, with closing expected September 21, 2026.
Electra had already built a sizeable private financing base ahead of the IPO, including a USD 183 million Series C in October 2025 co-led by Nextech and EQT Life Sciences, with participation from Sanofi and other institutional investors. The company had previously raised USD 84 million in a Series B in 2022.
Electra’s lead asset, ipsoprubart (ELA026), is a pan-SIRP antibody in a registrational Phase II/III study for secondary hemophagocytic lymphohistiocytosis (sHLH), a severe hyperinflammatory disorder with no broadly approved therapy. In an earlier Phase Ib study, Electra reported a 100% overall response rate and 92% Day-60 survival among 12 frontline patients with malignancy-associated HLH, compared with historical two-month survival of around 50%. Ipsoprubart holds FDA Fast Track, Breakthrough Therapy, and Orphan Drug designations, as well as EMA PRIME status.