Zenas BioPharma shares fell again premarket after plunging 52% Monday, as Phase 3 data for its autoimmune drug obexelimab, though meeting the primary endpoint, showed a 27% flare rate well above prior expectations of about 10% and weaker than Amgen Uplizna. Zenas still plans to file for FDA approval in Q2 2026, and Citi remains positive on approval odds.