Sanofi-backed Electra Therapeutics filed for an IPO after the Labor Day holiday to fund an immunology and cancer pipeline, including a Phase 2/3 trial for ipsoprubart (formerly ELA026). The filing describes an effort to bring the monoclonal antibody to patients with secondary hemophagocytic lymphohistiocytosis (sHLH), a rare, life-threatening inflammatory syndrome with multiple upstream triggers. Electra says ipsoprubart targets SIRP proteins to selectively deplete pathological immune cells, and it received breakthrough therapy designation from the FDA as well as PRIME designation from the EMA. The company also cites Phase 1b results in malignancy-associated HLH and outlines plans to advance additional candidates. The IPO filing matters for capital formation because sHLH and signal-regulatory protein targeting represent focused competition in immunology, where trial momentum and regulatory designations can materially affect valuation and partner interest.