Zenas BioPharma (ZBIO) Company Report

Zenas BioPharma reported positive top-line results from the INDIGO phase 3 study of obexelimab for IgG4-related disease, demonstrating a 56% risk reduction in time to disease flare and 92% of evaluable patients remaining flare-free at six months in the open-label extension.
The company plans to file for BLA for obexelimab in the U.S. in Q2 2026 and in Europe in H2 2026, with market research suggesting a potential 47% market share in IgG4-RD within three years and obexelimab becoming a greater than $1 billion drug in the U.S..
Top-line results for the Sunstone study in lupus, including the 24-week BICLA primary endpoint and biomarker analysis, are expected in Q4 2026.
Zenas BioPharma's oral IL-17 (ZB021) is set to enter the clinic mid-2026, targeting psoriasis by the end of 2026, and its TYK2 brain penetrant will enter phase 1 by the end of 2026.

Feb 11, 2026, 6:30 PM

Transcript

Zenas BioPharma Highlights Positive Obexelimab Phase 3 Results and Upcoming Pipeline Milestones

ZBIO

Product Launch

New Projects/Investments

Zenas BioPharma reported positive top-line results from the INDIGO Phase 3 study of obexelimab for IgG4-related disease, demonstrating a 56% risk reduction in time to disease flare and 92% of patients remaining flare-free at six months in the open-label extension.
Market research indicates a 47% market share allocation for obexelimab three years out and a potential to be a greater than $1 billion drug in the U.S., with a Biologics License Application (BLA) filing expected in Q2 in the U.S. and H2 in Europe.
The Sunstone study for the lupus program is anticipated to report top-line results in Q4, including the 24-week BICLA primary endpoint and biomarker data.
The company's pipeline includes an oral IL-17 (ZB021), which is projected to enter the clinic mid-year, with psoriasis outcome data expected next year.

Feb 11, 2026, 6:30 PM

Transcript

Zenas BioPharma Announces Positive Phase 3 Results for Obexelimab in IgG4-RD

ZBIO

Study Result

New Projects/Investments

Product Launch

Zenas BioPharma's Obexelimab Phase 3 INDIGO trial for IgG4-RD met its primary endpoint and all four key secondary endpoints with high statistical significance.
Obexelimab reduced the risk of IgG4-RD flare by 56% (Hazard Ratio = 0.443, p=0.0005) and demonstrated a compelling safety and tolerability profile.
The company plans to submit a Biologics License Application (BLA) to the U.S. FDA in 2Q 2026, followed by a Marketing Authorization Application (MAA) to the EMA in 2H 2026 for Obexelimab in IgG4-RD.
The estimated U.S. commercial opportunity for Obexelimab in IgG4-RD is approximately $3 billion.
Upcoming catalysts include 24-week results for Obexelimab in Relapsing Multiple Sclerosis (RMS) in 1Q 2026 and primary endpoint data for Obexelimab in Systemic Lupus Erythematosus (SLE) in Q4 2026.

Jan 5, 2026, 1:00 PM

Presentation

Zenas BioPharma Announces Positive Phase III INDIGO Trial Results for Obexelimab

ZBIO

New Projects/Investments

Zenas BioPharma announced positive top-line results from its registrational phase III INDIGO trial for obexelimab for the treatment of immunoglobulin G4-related disease (IgG4-RD).
The trial met its primary endpoint, demonstrating that obexelimab significantly reduced the risk of IgG4-RD flare by 56% compared to placebo, with a p-value of 0.0005.
Obexelimab also met all four key secondary endpoints with high statistical significance and showed a compelling safety and tolerability profile, including lower incidences of serious adverse events and overall rates of infections compared to placebo.
The company plans to submit a Biologics License Application (BLA) to the U.S. FDA in the second quarter and a marketing authorization application to the European Medicines Agency in the second half of this year.
Zenas BioPharma is in active discussions with Royalty Pharma regarding a $75 million milestone payment related to the phase III data, for which they are not currently eligible under the existing agreement.

Jan 5, 2026, 1:00 PM

Transcript

Zenas BioPharma announces positive Phase III INDIGO trial results for obexelimab in IgG4-RD

ZBIO

Product Launch

New Projects/Investments

Revenue Acceleration/Inflection

Zenas BioPharma's registrational phase III INDIGO trial for obexelimab in IgG4-RD met its primary endpoint, showing a 56% reduction in the risk of disease flare compared to placebo (hazard ratio of 0.443, p-value of 0.0005).
Obexelimab also met all four key secondary endpoints with high statistical significance and demonstrated a compelling safety and tolerability profile, with 27% of patients experiencing flares in the obexelimab arm versus 55% in the placebo arm.
The company plans to submit a BLA to the U.S. FDA in the second quarter of 2026 and an MAA to the European Medicines Agency in the second half of 2026 for obexelimab in IgG4-RD.
Zenas estimates the market opportunity for obexelimab in IgG4-RD to be approximately $3 billion in the U.S. and $2 billion in Europe.
Zenas is in active discussions with Royalty Pharma regarding a $75 million milestone payment related to the phase III data, for which Zenas is currently not eligible under the existing agreement.

Jan 5, 2026, 1:00 PM

Transcript

Zenas Announces Positive Phase III INDIGO Trial Results for Obexelimab

ZBIO

Product Launch

Revenue Acceleration/Inflection

Zenas (ZBIO) announced successful results from its Phase III INDIGO trial for obexelimab in IgG4-Related Disease (IgG4-RD), meeting the primary endpoint and all four key secondary endpoints with high statistical significance.
Obexelimab demonstrated a 56% reduction in the risk of IgG4-RD flare compared to placebo (hazard ratio of 0.443, p-value of 0.0005) and a compelling safety profile, with lower incidences of serious adverse events and overall infections compared to placebo.
The company plans to submit a Biologics License Application (BLA) to the U.S. Food and Drug Administration (FDA) in Q2 2026 and a Marketing Authorization Application to the European Medicines Agency in H2 2026.
The estimated market opportunity for obexelimab in IgG4-RD is approximately $3 billion in the U.S. and $2 billion in Europe.

Jan 5, 2026, 1:00 PM

Transcript

Zenas BioPharma Announces Positive Phase 3 INDIGO Trial Results for Obexelimab

ZBIO

New Projects/Investments

Guidance Update

Zenas BioPharma announced positive results from the Phase 3 INDIGO trial of obexelimab in Immunoglobulin G4-Related Disease (IgG4-RD).
Obexelimab met its primary endpoint, demonstrating a 56% reduction in the risk of IgG4-RD flare compared to placebo, and was well tolerated with a favorable safety profile.
The company anticipates submitting a Biologics License Application (BLA) to the FDA in the second quarter of 2026 and a Marketing Authorization Application (MAA) to the EMA in the second half of 2026 for obexelimab in IgG4-RD.
Zenas is in active discussions with Royalty Pharma Investments 2019 ICAV regarding a $75 million milestone payment related to the INDIGO Data Milestone, which was not met under the original terms.

Jan 5, 2026, 12:16 PM

8-K

Zenas BioPharma Highlights 2025 Accomplishments and Upcoming Milestones

ZBIO

New Projects/Investments

Zenas BioPharma completed the Phase III IgG4-related disease trial of obexelimab in November 2025, with data expected by the end of 2025.
The company reported strong Phase II results for obexelimab in relapsing multiple sclerosis (RMS) from the MoonStone study, demonstrating a 95% reduction in new T1 GAD-enhancing lesions versus placebo.
Zenas expanded its pipeline through business development, adding orelabrutinib (now in Phase III for progressive MS) and two other molecules (an oral IL-17 inhibitor and a brain penetrant TYK2 inhibitor) expected in the clinic in 2026.
A $300 million potential financing deal with Royalty Pharma was secured, primarily supporting obexelimab.
The company expects Phase II SunStone results for obexelimab in lupus in Q3 2026, aiming for a significant difference from placebo.

Dec 3, 2025, 12:55 PM

Transcript

Zenas BioPharma Wraps Up 2025 with Key Clinical Milestones and Pipeline Expansion

ZBIO

New Projects/Investments

M&A

Product Launch

Zenas BioPharma completed enrollment for the Phase III IgG4-related disease trial of obexelimab in November 2025, with data expected around year-end 2025, and is preparing for BLA activities.
The company reported strong results from the MOONSTONE Global Phase II study in relapsing multiple sclerosis (RMS) for obexelimab, showing a 95% reduction in new T1 GAD-enhancing lesions versus placebo.
Zenas significantly expanded its pipeline by acquiring orelabrutinib, a BTK inhibitor currently in a Phase III trial for progressive MS, and secured a $300 million potential financing deal with Royalty Pharma.
The company anticipates a substantial market opportunity for obexelimab in IgG4-related disease, estimating 30,000 to 40,000 patients in the U.S. and Europe, with competitive drug pricing exceeding $250,000 annually.

Dec 3, 2025, 12:55 PM

Transcript

Zenas BioPharma provides update on obexelimab Phase III IgG4-RD results and pipeline expansion

ZBIO

New Projects/Investments

M&A

Zenas BioPharma expects top-line Phase III results for obexelimab in IgG4-related disease around the end of 2025, following the last patient out. The trial, with 194 patients, is considered overpowered, anticipating a 60% flare rate in the control arm.
The company reported outstanding Phase II data for obexelimab in relapsing multiple sclerosis (RMS), showing a 95% risk reduction in new enhancing GAD lesions.
Zenas has expanded its pipeline through a transaction, including rilzabrutinib, a BTK inhibitor for progressive multiple sclerosis (PPMS and SPMS), with a PPMS trial underway and an SPMS trial set to begin in Q1 2026.
The estimated market opportunity for obexelimab in IgG4-RD in the U.S. is over $3 billion for patients requiring continuous therapy, with market research suggesting a potential 45% share.