- Dose-related clinical activity: Week 12 clinical remission of 23.1% (3/13) in higher-dose Cohort 2 vs. 11.4% (4/35) in lower-dose Cohort 1
- 38.9% (7/18) of participants with a Day 29 trough concentration at or above the target level, pooled from both cohorts, achieved clinical remission at Week 12
- ALTB-268 was well tolerated
- A global Phase 2b placebo-controlled trial in a broader population is planned to start in 2027
SAN FRANCISCO, Oct. 20, 2026 (GLOBE NEWSWIRE) -- AltruBio Inc. ("AltruBio" or "the Company"), a clinical-stage biotech company developing novel immune modulators to address the unmet need in immunological and inflammatory diseases, today announced positive data from its open-label Phase 2a ASCEND UC2a trial evaluating ALTB-268, its first-in-class subcutaneous (SC) PSGL-1 immune modulator, in patients with moderately to severely active ulcerative colitis (UC) who had all failed prior advanced therapies.
The data were featured in an oral presentation today by David T. Rubin, MD, AGAF, MACG, FASGE, FACP, Joseph B. Kirsner Professor of Medicine, University of Chicago, at the United European Gastroenterology (UEG) Week 2026 conference.
“The remission rates observed in this trial are highly encouraging, particularly in this advanced therapy-refractory UC population, and support further evaluation in a randomized study,” said Judy Chou, PhD, President and Chief Executive Officer of AltruBio. “The observed relationship between drug exposure and clinical remission provides further validation of ALTB-268’s unique mechanism of action. We look forward to evaluating ALTB-268 in the upcoming Phase 2b study in both advanced therapy-experienced and advanced therapy-naïve patients. By restoring T-cell balance rather than broadly suppressing the immune system, ALTB-268 has the potential to reshape the treatment landscape for patients with UC.”
Dr. Rubin added, “The benefits of this novel treatment in the complex patients with long-standing disease who had not adequately responded to other advanced therapies are important initial signals. The planned placebo-controlled Phase 2b trial of both advanced therapy-experienced and advanced therapy-naïve patients will be important in further demonstrating the clinical profile of ALTB-268 and its unique role in the evolving UC treatment paradigm.”
AltruBio is preparing the global Phase 2b ASCEND UC2b study, expected to begin in 2027. The placebo-controlled trial will evaluate two active dose levels of ALTB-268 and assess both induction of clinical remission and durability of response during maintenance.
Key data highlights include:
- Clinical remission: 11.4% (4/35) of patients in lower-dose Cohort 1 and 23.1% (3/13) in higher-dose Cohort 2.
- Endoscopic improvement: 17.1% (6/35) in Cohort 1 and 23.1% (3/13) in Cohort 2.
- Clinical response: 34.3% (12/35) in Cohort 1 and 53.8% (7/13) in Cohort 2.
- Improvement in patient-reported quality of life, measured by the Inflammatory Bowel Disease Questionnaire (IBDQ): 51.4% (18/35) in Cohort 1 and 53.8% (7/13) in Cohort 2.
- In an exploratory analysis pooling both cohorts, among participants with a Day 29 trough concentration at or above the target level (n=18), 38.9% (7/18) achieved clinical remission and 38.9% (7/18) achieved endoscopic improvement at Week 12. Clinical response was 55.6% (10/18) and IBDQ response was also 55.6% (10/18).
- Exposure-response relationship: Preliminary exposure-response modeling showed a positive relationship between Day 29 trough concentration and clinical remission at Week 12.
- Safety and tolerability: ALTB-268 was well tolerated. The overall proportion of treatment-emergent adverse events (TEAEs) was similar across both cohorts despite a two-fold difference in dose. The most common TEAE was injection site reaction, which decreased with repeat administration and was not observed in either cohort by the end of the induction period. One serious adverse event (SAE) was reported, in Cohort 1, and there were no deaths.
UEGW Presentation Details
Title: A Phase IIa open label study of ALTB-268, an anti-CD162 (PSGL-1) antibody in patients with moderately to severely active ulcerative colitis with an inadequate response to prior advanced therapy
Session date and time: October 20, 2026, 9:10–9:20 a.m. CET
Session: Looking into the future: Novel therapeutics in IBD (Part 1)
About ASCEND UC2a
ASCEND UC2a (NCT06109441) is a Phase 2a, open-label, dose-exploration study evaluating the efficacy, safety, tolerability and pharmacokinetics of subcutaneous ALTB-268 in participants with moderately to severely active ulcerative colitis who had an inadequate response to at least one prior advanced therapy (biologics, JAK inhibitors or S1P receptor modulators). Cohort 1 and Cohort 2 were enrolled sequentially. Participants in either cohort were administered ALTB-268 for a 12-week induction period, followed by a post-induction period in which dosing continued at the investigator’s discretion. Exploratory efficacy endpoints include clinical response, clinical remission, endoscopic improvement and IBDQ response.
About ALTB-268
ALTB-268 is a subcutaneously administered, tetravalent agonist antibody targeting PSGL-1, a key immune modulator. It preferentially downregulates chronically activated, late-stage T effector cells, leading to their exhaustion and/or ultimate apoptosis. Its unique mechanism of action to restore immune balance has been clinically validated by AltruBio’s first-generation asset, which previously demonstrated promising Phase 2 results in ulcerative colitis, psoriasis, psoriatic arthritis, and steroid-refractory/treatment-refractory acute graft-versus-host disease (SR/TR-aGvHD), including improved patient outcomes and clinical efficacy.
About AltruBio Inc.
AltruBio is a clinical-stage biotechnology company developing novel therapies leveraging immune modulator agonism to address unmet medical needs in immunological and inflammatory diseases. The Company’s lead candidate, ALTB-268, acts as an immune modulator, designed to activate natural pathways that downregulate a chronically overactivated immune system to restore balance. Currently being evaluated in a Phase 2 trial in ulcerative colitis, ALTB-268 holds the potential to be a pipeline-in-a-product asset to address a range of inflammatory diseases, which AltruBio plans to explore in the upcoming Phase 2b ASCEND UC2b trial. Led by an expert team with successful track records in drug development and commercialization in immunology, AltruBio is dedicated to delivering safer, more effective, and durable biologic treatments to improve the lives of patients.
Contacts
AltruBio Inc:
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info@altrubio.com
Media Contact:
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Maggie Whitney
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