Zenas BioPharma, Inc. 8-K

What Happened
Zenas BioPharma (ZBIO) filed an 8‑K on Jan 5, 2026 reporting positive, registration‑directed Phase 3 results from the INDIGO trial of obexelimab in immunoglobulin G4‑related disease (IgG4‑RD) and a preliminary, unaudited cash, cash equivalents and investments balance of approximately $360.5 million as of December 31, 2025 (which the company says should fund operations through the end of 2026). The INDIGO trial enrolled 194 patients (obexelimab n=97; placebo n=97); obexelimab reduced the risk of IgG4‑RD flare requiring rescue therapy by 56% versus placebo (hazard ratio 0.443, p=0.0005) and achieved highly significant results on all four key secondary endpoints. Zenas says it plans to submit a BLA to the FDA in Q2 2026 and an MAA to the EMA in H2 2026.

Key Details

• Preliminary cash position: ~$360.5 million as of Dec 31, 2025; unaudited and subject to closing procedures and potential change. Auditor (Ernst & Young) did not audit or review this preliminary number.
• INDIGO Phase 3: 194 patients randomized (97/97); primary endpoint HR 0.443 (56% reduction), p=0.0005. Key secondaries also highly significant (examples: time to first investigator‑determined flare p=0.0001; number of flares p=0.0008; complete remission proportion p=0.0049).
• Safety: Serious adverse events lower with obexelimab (10%) vs placebo (19%); Grade 3 infections 2% vs 4%; injection‑site reactions similar (3.5% vs 2.3%). Three malignancies identified and deemed unrelated.
• Commercial / financing notes: Zenas has a Royalty Purchase Agreement with Royalty Pharma (RPI) for up to $300M ($75M paid Sept 2, 2025; remaining $75M milestones tied to INDIGO data, FDA approval in IgG4‑RD, and FDA approval in SLE). The INDIGO milestone is currently not payable; discussions with RPI are ongoing. Bristol Myers Squibb holds obexelimab rights in Japan, South Korea, Taiwan, Hong Kong, Singapore and Australia.

Why It Matters
For investors, the INDIGO Phase 3 readout materially advances obexelimab toward potential U.S. and EU approvals (BLA expected Q2 2026, MAA H2 2026), which could unlock future revenue and milestone payments. The company’s reported preliminary cash balance (~$360.5M) — while unaudited and subject to change — is stated to cover operations through the end of 2026, reducing near‑term financing pressure. However, milestone payments under the RPI agreement are uncertain (the INDIGO milestone isn’t currently payable), and the cash figure is preliminary, so investors should watch the audited year‑end results and regulatory filing progress.