AltruBio Inc. (“AltruBio” or “the Company”), a clinical stage biotechnology company dedicated to the development of novel therapeutics for the treatment of immunological diseases with high unmet medical needs, today announced an oversubscribed Series B financing of up to $225 million. AltruBio plans to use the proceeds of the financing to advance the clinical development of the Company’s first-in-class, novel immune checkpoint enhancer (ICE) PSGL-1 agonist antibody, ALTB-268. The funds will be used to support ongoing and planned Phase 2 clinical trials in ulcerative colitis (UC), one of many immunological disorders where the mechanism has been clinically validated.

The financing was led by BVF Partners LP with participation from new investors RA Capital Management, Cormorant Asset Management, and Soleus Capital, as well as existing investors aMoon Fund and Blackstone Multi-Asset Investing, with other new and existing investors joining the syndicate.

The Company’s first-in-class, novel ICE agonist antibody, ALTB-268, is currently being studied in a Phase 2a exploratory biomarker study in patients with biologic refractory UC with an anticipated readout for its primary endpoint of clinical remission per modified Mayo score in 1H 2025. The company plans to initiate a global Phase 2b randomized, placebo-controlled clinical trial with a primary endpoint of clinical remission in both advanced therapy experienced and treatment naive patients with moderately to severely active UC. This study is anticipated to read out in 2H of 2026.

"We are honored to welcome this esteemed new group of investors, whose participation complements the support of our existing world-class investor group. Their collective backing not only affirms the potential of our program and company but also our mission of developing durable biologic therapies for patients suffering from autoimmune diseases,” said Dr. Judy Chou, President and Chief Executive Officer of AltruBio. “With this substantial investment, we are one step closer to bringing our first-in-class, novel immune checkpoint enhancer, ALTB-268, through our ongoing Phase 2a exploratory biomarker study and initiate an additional Phase 2b study, while paving the way for potential indication expansion beyond ulcerative colitis. With our experienced team in place and this significant financing, we are poised to accelerate our efforts and deliver innovative treatments to patients in need."

“Treatment options remain limited in many autoimmune conditions, including moderate to severe ulcerative colitis, and novel mechanisms are sorely needed,” commented Gorjan Hrustanovic, Ph.D., Managing Director at BVF Partners LP. “We are excited to support AltruBio and their commitment to developing a potential first-in-class medicine across multiple autoimmune indications, starting with UC.”

“Our investment in AltruBio represents an exciting opportunity to contribute to the dynamic and rapidly evolving landscape of the inflammatory and immunological space. The heightened interest and substantial funding in this sector underscore the urgent need for innovative solutions to address the unmet medical needs of patients. We share a collective vision with AltruBio to advance first-in-class medicines, recognizing the potential to revolutionize patient care and drive impactful change within this field," said Jake Simson, Ph.D., Partner of RA Capital Management.

About ALTB-268ALTB-268 is a tetravalent PSGL-1 agonist antibody that acts as an immune checkpoint enhancer (ICE) to preferentially downregulate chronically activated T-cells by inhibiting the T-cell effector function, promoting T-cell down regulation. ALTB-268 is designed to help restore the immune system to a state of balance without systemic suppression, and by treating immune diseases at their source. Its unique mechanism of action is the same as the bivalent intravenously administered ICE, ALTB-168, which has previously demonstrated promising Phase 2 results in ulcerative colitis, psoriasis, psoriatic arthritis, and SR/TR-aGvHD, including improved patient outcomes and clinically meaningful efficacy. ALTB-268 exhibited increased potency in preclinical studies and is formulated for subcutaneous dosing for patient-friendly administration. A Phase 1 study of ALTB-268 has demonstrated the safety and tolerability in healthy volunteers with no serious adverse events across all cohorts. A Phase 2a exploratory biomarker study for ALTB-268 in biologics-refractory ulcerative colitis patients is currently enrolling patients and a randomized Phase 2b study in ulcerative colitis is planned to be initiated later in 2024. Based on the relevance of T-cell modulation in many immunological diseases, ALTB-268 has broad expansion potential in different indications and hence has significant promise as a “pipeline-in-a-product.”

About AltruBio Inc.AltruBio is a clinical-stage biotechnology company that specializes in developing novel therapies leveraging immune checkpoint agonism to enhance the function of natural pathways to downregulate an overactivated immune system. It is believed the mechanism of the immune checkpoint enhancers (ICEs) may hold the key to addressing the pressing medical needs of patients with autoimmune and inflammatory disorders. The Company’s research team was the first to discover the novel role PSGL-1 plays as an important immune checkpoint regulator and leveraged its ability to downregulate chronic effector T-cell function and promote down regulation. Robust clinical data validates proof of mechanism of the Company’s ICE therapy, ALTB-168, through enhancement of PSGL-1 function. ALTB-168 is designed to preferentially downregulate chronically activated late-stage T-cells in several diseases including ulcerative colitis, steroid refractory acute graft-versus-host disease (SR-aGvHD), psoriatic arthritis, and psoriasis, and was shown to be well tolerated with durable responses. Leveraging the same binding domain and novel mechanism demonstrated for ALTB-168, the Company is advancing a more potent tetravalent ICE, ALTB-268, making it suitable for subcutaneous and patient-friendly administration. ​Led by an expert team with successful track records in drug development and commercialization in immunological diseases, AltruBio’s mission is to bring safer, more effective, and durable biologic treatments to improve the lives of patients.

MTS Securities, LLC acted as the exclusive placement agent in connection with the financing.

Note on Forward-Looking StatementsStatements made in this news release that are not historical facts are forward-looking statements. These forward-looking statements include, but are not limited to, statements about the Series B financing, including those with respect to subsequent closings, the use of proceeds from the Series B financing, and the progress and timing of the Company’s clinical trials, including the timing and availability of data from such trials. Words such as expects, believes, plans, anticipates, intends, potential, design and similar expressions are intended to identify forward-looking statements. Actual results may differ materially from those projected in any forward-looking statement. Specifically, there are a number of important factors that could cause actual results to differ materially from those anticipated, such as the Company's ability to achieve certain milestones and complete subsequent closings of the Series B financing, raise additional capital, and risks related to the Company's ability to initiate, and enroll patients in, planned clinical trials. The forward-looking statements included in this press release represent the Company’s views as of the date hereof. These forward-looking statements should not be relied upon as representing the Company’s views as of any date subsequent to the date hereof.

The Company assumes no obligation to update any forward-looking statements as a result of new information, future events or developments, except as required by law.

Contacts

AltruBio Inc: +1-415-655-6603 info@altrubio.com

Media Contact:LifeSci CommunicationsLuke Shiplolshiplo@lifescicomms.com