ADDED
Our lead I I product candidate, obexelimab, is a bifunctional monoclonal antibody designed to bind both CD19 and Fc RIIb, which are broadly present across B cell lineage, in order to inhibit the activity of cells that are implicated in many autoimmune diseases without depleting them.
The first three indications we are pursuing include immunoglobulin G4-related disease ( IgG4-RD ) through a registration-directed Phase 3 trial which reported topline data in January 2026, and relapsing multiple sclerosis ( RMS ), through a Phase 2, double-blind, randomized, placebo-controlled trial which reported topline data in October 2025, and systemic lupus erythematosus ( SLE ) through an ongoing Phase 2, double-blind, randomized, placebo-controlled trial for which we expect to report topline results, including biomarker data, in the fourth quarter of 2026.
In January 2026, we reported positive results from the Phase 3 trial of obexelimab in patients with IgG4-RD (the INDIGO ) trial.
Obexelimab met the primary endpoint, demonstrating a highly statistically significant and clinically meaningful 56% reduction in the risk of IgG4-RD flare compared to placebo (Hazard Ratio 0.44, p=0.0005) and also met and demonstrated highly statistically significant activity compared to placebo on all four key secondary endpoints.
Obexelimab was well tolerated with a safety profile consistent with that observed in previously completed clinical trials.
Based on these results, we plan to submit the obexelimab Biologics License Application ( BLA ) to the U.S.
Food and Drug Administration ( FDA ) for the treatment of IgG4-RD in the second quarter of 2026.
We also intend to submit a Marketing Authorization Application ( MAA ) to the European Medicines Agency ( EMA ) in the second half of 2026.
In October 2025, we reported that the Phase 2 trial for RMS ( MoonStone ) met its 12-week primary endpoint, demonstrating a highly statistically significant 95% relative reduction in the cumulative number of new gadolinium-enhancing ( GdE ) T1 hyperintense lesions over week 8 and week 12 compared with placebo (p=0.0009).
In February 2026, we reported the 24-week data from MoonStone trial which confirmed the reductions in total GdE T1 hyperintense lesions observed with obexelimab over weeks 8 and 12 were maintained through week 24; unadjusted mean numbers of new lesions per scan were 0.87 at baseline, 0.08 at week 12 and 0.04 at week 24 for obexelimab indicating a 95% reduction.
REMOVED
With the evolving understanding of the pathogenesis of autoimmune diseases, along with the expansion of promising immunology-based pharmacologic targets, we are building an immunology and inflammation ( I I ) focused biopharmaceutical company.
The first three indications we are pursuing include immunoglobulin G4-related disease ( IgG4-RD ) through an ongoing registration-directed Phase 3 trial which completed enrollment in November 2024 and relapsing multiple sclerosis ( RMS ) and systemic lupus erythematosus ( SLE ) through ongoing Phase 2, double-blind, randomized, placebo-controlled trials, each of which are currently enrolling.
Beyond our lead product candidate, obexelimab, we have two other programs for the potential treatment of other I I indications that we may continue to advance and ultimately develop and commercialize with partners.
Other anti-CD19 and CD20 targeting antibodies rely on antibody-dependent cell-mediated cytotoxicity ( ADCC ), complement-dependent cytotoxicity ( CDC ) and/or apoptosis or programmed cell death as a key component of their mechanism of action.
Obexelimab has been evaluated in five completed clinical trials in which a total of 198 subjects have received obexelimab either as IV infusion at doses of up to 10 mg/kg (n=158) or as a SC injection at doses of up to 375 mg (n=40).
Other Programs Beyond our lead product candidate, obexelimab, we have two other programs for the potential treatment of other I I indications that we may continue to advance and ultimately develop and commercialize with partners.
Product Candidate Territory Plan of Development ZB002 (anti-TNF mAb) Global Phase 1b multiple ascending dose ("MAD") study in patients with RA ongoing ZB004 (CTLA-4-Ig fusion) Global Phase 1 single ascending dose ("SAD") study in healthy volunteers completed ZB002, an anti-TNF therapy designed to have an extended half-life as compared to existing anti-TNF therapies.
ZB002 is a recombinant human monoclonal antibody directed at human TNF .
ZB002 has an identical amino acid sequence to Humira (adalimumab) in the TNF -binding region of the fragment variable domain; however, the Fc domain of ZB002 contains modifications designed to extend its half-life in vivo .
We also own the global development and commercialization rights to ZB004, a CTLA-4-Ig fusion protein designed to have an extended half-life compared to approved CTLA-4-Ig fusion protein therapies, such as Orencia (abatacept) and Nulojix (belatacept).