Zenas BioPharma Stock (ZBIO) on Citi’s Catalyst Watchlist Ahead of Key Trial Data

Zenas BioPharma stock (ZBIO) has landed on Citi's “upside 90-day catalyst watch” list, as markets anticipate crucial Phase 3 INDIGO trial results for its lead drug candidate, obexelimab. The focus centers on the treatment of Immunoglobulin G4-Related Disease (IgG4-RD), with expectations building around the early January data readout.

ZBIO's stock performance reflects this anticipation, having surged 301.22% since the start of 2025, although it has experienced a recent pullback of 5.5% over the past month.

The Phase 3 INDIGO trial, which concluded targeted enrollment in November 2024, represents the largest study conducted for IgG4-RD, encompassing approximately 190 patients across 100 sites in 20 countries. The primary endpoint of the trial assesses the time to first disease flare over a 52-week period. Secondary endpoints include the rate of flares, achievement of complete remission, and changes in glucocorticoid toxicity. Citi believes obexlimab is positioned to show a statistically significant reduction in flares relative to placebo.

Zenas has also strategically bolstered its financial position, securing up to $300 million in funding from Royalty Pharma during September 2025. The agreement includes an initial $75 million payment, with additional funds contingent upon the INDIGO trial results and subsequent FDA approvals. This funding is earmarked to support the ongoing development of obexelimab and its potential commercial launch in the United States.

Analyst sentiment towards Zenas remains largely positive. Morgan Stanley maintained an “Overweight” rating with a price target of $40.22 in November, reflecting confidence in obexelimab's potential. 

Beyond obexelimab, Zenas has been actively expanding its pipeline. In October, the company licensed three autoimmune product candidates from InnoCare Pharma, including orelabrutinib, a BTK inhibitor currently in Phase 3 development for multiple sclerosis. This strategic move diversifies Zenas' portfolio and strengthens its position in the broader autoimmune treatment landscape.

The near-term outlook for Zenas BioPharma is inextricably linked to the results of the INDIGO trial. While strategic partnerships and pipeline expansion provide a fundamental base, the market's focus remains firmly on obexelimab's potential.