First-in-human study of EPI-326 will evaluate the company’s lead tissue-selective EGFR degrader in patients with NSCLC and HNSCC with potential to expand to CRC

AACR 2026 presentations, including New Drugs on the Horizon, highlight new data supporting monotherapy and combination opportunities for EPI-326 and the company’s broader EpiTAC pipeline

EpiBiologics, a leader in tissue-selective extracellular protein degradation, today announced that the first patient has been dosed with EPI-326 in its global Phase 1 clinical study. EPI-326 is the company’s tissue-selective bispecific antibody that degrades all oncogenic mutant and wild type forms of EGFR for EGFR-driven cancers. The first-in-human study is evaluating EPI-326 in patients with advanced non-small cell lung cancer (NSCLC) and head and neck squamous cell carcinoma (HNSCC) with the potential to expand into colorectal cancer (CRC).

“Patients face persistent challenges with current EGFR-targeted therapies, including resistance and poor tolerability,” said Eric Humke, M.D., Ph.D., Chief Medical Officer of EpiBiologics. “EPI-326 was designed to address those limitations through a mutation-agnostic, tissue-selective approach to localize EGFR degradation to tumors while sparing healthy tissue. We believe EPI-326 can drive strong durable efficacy as a monotherapy and in combinations, and ultimately enable treatment in earlier settings.”

The Phase 1 study (NCT07462377) is designed to evaluate the safety, tolerability, pharmacokinetics and preliminary anti-tumor activity of EPI-326 as a monotherapy in patients with advanced NSCLC and HNSCC. The study is currently enrolling patients at sites in the U.S. and is planned to initiate sites in the Asia-Pacific region, including South Korea.

AACR Highlights

New data presented today at the AACR New Drugs on the Horizon session highlight EPI-326’s activity across multiple tumor models, potential in combination settings, and encouraging tolerability profile:

• Broad anti-tumor activity: EPI-326 showed robust preclinical in vivo efficacy in both classical and drug-resistant (C797S) EGFR-mutant NSCLC models, as well as in wildtype HNSCC and CRC tumor models. In an EGFR-mutant NSCLC preclinical model, EPI-326 monotherapy drove a high complete response rate and demonstrated stronger activity than EGFR inhibitors.
• Combination potential: Preclinical studies combining EPI-326 with frontline standard-of-care therapies, including tyrosine kinase inhibitors (TKIs) and KRAS inhibitors for NSCLC and CRC cancers respectively, led to deeper and more durable anti-tumor responses.
• Favorable tolerability profile: EPI-326 was well tolerated in multidose non-human primate toxicology studies to a maximal feasible dose of 204 mg/kg, with no evidence of stereotypical EGFR-related toxicities. This safety window supports the company’s monotherapy strategy and provides a strong basis for evaluating EPI-326 in combination with standard-of-care therapies.

“What stands out in these data is the combination of robust anti-tumor activity with an excellent tolerability profile,” said Shyra Gardai, Ph.D., Chief Scientific Officer of EpiBiologics. “This is the central promise of tissue-selective degradation. We are now pursuing similar therapeutic approaches across multiple targets in oncology and immunology.”

Additional AACR presentations highlight EpiBiologics’ pipeline progress. New data from the company’s cMET degrader-ADC support advancement of this dual mechanism EpiTAC, which combines targeted degradation with a cytotoxic payload and may safely address high unmet needs, including tumors with low cMET expression. Together with new data from the company’s cKIT program, these presentations underscore the potential to generate tissue-selective EpiTACs against receptor tyrosine kinases implicated across multiple tumor types.

“Advancing EPI-326 into the clinic, alongside key data presented at AACR, gives us an early view into the broader opportunity for EpiTACs,” said Ann Lee-Karlon, Ph.D., Chief Executive Officer of EpiBiologics. “This milestone builds on the momentum of our recent Series B financing, and we are delighted to welcome Roche Venture Fund as a new investor in our syndicate. Our goal is to build highly differentiated bispecific antibodies to selectively degrade membrane and soluble targets for oncology and immunology where new approaches are needed the most.”

Details of the poster presentations are as follows:

Title: “Dual modality of EpiTAC bispecific degrader ADCs combines c-MET degradation with cytotoxic payload delivery to overcome limitations of current c-MET-targeted therapies”
Date & Time: Mon., April 20th, 9 a.m.-12 p.m. PT
Presenters: Lisa Marshall, Kenneth Ng, Shruti Yadav

Title: “Discovery of mutation-independent cKit degrading bispecific antibodies that suppress tumor growth in preclinical models of GIST”
Date & Time: Tues., April 21st, 9 a.m.-12 p.m. PT
Presenters: Ken Flanagan, Kenneth Ng, Shruti Yadav

About EPI-326
EPI-326 is a tissue-selective bispecific antibody that degrades all oncogenic forms of EGFR, is mutation-agnostic, and overcomes limitations of existing EGFR therapies by localizing degradation to the tumor while sparing normal healthy tissue. It is currently being evaluated in a global Phase 1 clinical trial (NCT07462377) in patients with NSCLC and HNSCC with the potential to expand to CRC.

About EpiBiologics
EpiBiologics is a clinical-stage company developing novel bispecific antibodies (EpiTACs) to selectively degrade disease-causing extracellular membranes and soluble proteins. EpiBiologics was founded on pioneering work from scientific founder Dr. Jim Wells of the University of California, San Francisco (UCSF). Headquartered in the San Francisco Bay Area, EpiBiologics is backed by leading healthcare investors and aims to develop first-in-class and best-in-class targeted therapies across multiple therapeutic areas, including oncology and immunology. For more information, please visit epibiologics.com and follow us on LinkedIn.

View source version on businesswire.com: https://www.businesswire.com/news/home/20260419722175/en/