Phanes Therapeutics Announces Updated Phase 2 Clinical Trial Results of Spevatamig (PT886) in Combination with Chemotherapy in Frontline Treatment of Metastatic PDAC at the 2026 ASCO Annual Meeting

SAN DIEGO, May 28, 2026 /PRNewswire/ -- Phanes Therapeutics, Inc. (Phanes), a clinical stage biotech company focused on innovative drug discovery and development in oncology, released updated positive Phase 2 results of spevatamig (PT886) in combination with chemotherapy in frontline (1L) treatment of metastatic pancreatic ductal adenocarcinoma (PDAC) for the American Society of Clinical Oncology (ASCO) Annual Meeting 2026 . The full poster presentation will be held on Saturday, May 30 between 9am-12pm CDT during the Gastrointestinal Cancer - Gastroesophageal, Pancreatic, and Hepatobiliary Session (Abstract #4192, Poster #175).

• The data show spevatamig, an anti-CLDN18.2/CD47 bsAb, in combination with chemotherapy, has the potential to be an effective 1L treatment in patients with metastatic PDAC (mPDAC).
   
• The design of spevatamig with an optimized anti-CD47 arm mitigates hematological toxicity and improves GI tolerability, as evidenced by the results of the spevatamig monotherapy and combination therapy studies where >190 patients have been dosed globally.
   
• Spevatamig + GnP combination is well tolerated in 1L patients with mPDAC, with no significant additive toxicity to GnP.
   
• 2 mg/kg QW spevatamig + GnP showed promising efficacy (52.4% ORR, 90.5% DCR) when compared with the GnP arm in pivotal trials in 1L mPDAC; importantly, more than 90% of patients at this dose level had de novo metastatic disease, consistent with the baseline characteristics of the patient populations in pivotal Phase 3 trials.
   
• Median progression-free survival (mPFS) was 7.3 months, and median overall survival (mOS) was 14.7 months in US patients, where the median follow up time is 14.7 months.
   
• The efficacy data for 3 mg/kg spevatamig + GnP is still maturing. 3 mg/kg has the potential to be the dose level for a Phase 3 registrational study.
   
• Overall, the data support further development of spevatamig + GnP in a randomized Phase 3 trial in patients with 1L mPDAC.

Spevatamig is an innate immunity enhancer (I₂E), an emerging class of immuno-oncology (IO) agents. Unlike immune checkpoint inhibitors (ICIs) (also known as anti-PD1/anti-PD-L1 drugs) which activate T cells to kill cancer cells, I₂Es activate macrophages and dendritic cells to recognize and destroy cancer cells, providing an alternative mechanism to leverage the immune system to attack tumors, especially the so-called "cold tumors" that do not respond to ICIs.

"We are pleased to see the positive results at the first dose level of spevatamig in the 1L PDAC study. This result is significant because PDAC is considered a 'cold tumor' to ICIs. Now we have the opportunity to target PDAC with a new class of immunotherapy," said Ming Wang, PhD, MBA, Founder and CEO of Phanes. "The enrollment at the 3 mg/kg dose level is progressing rapidly and we hope to see efficacy data in the second half of 2026. We could be Phase 3 ready shortly after that. Our goal is to advance this exciting I₂E aggressively and deliver an innovative immunotherapy for patients with mPDAC."

ABOUT SPEVATAMIG

Spevatamig is a first-in-class native IgG-like bispecific antibody (bsAb) targeting claudin 18.2 and CD47. It was granted orphan drug designation (ODD) for the treatment of pancreatic cancer by the FDA in 2022 and was granted Fast Track designation for the treatment of patients with metastatic claudin 18.2-positive pancreatic adenocarcinoma in 2024. In 2023, Phanes entered into a clinical collaboration agreement with Merck (known as MSD outside the US and Canada) to study spevatamig in combination with pembrolizumab.

Phanes is conducting clinical trials with spevatamig in multiple cancer indications, including a Phase 2 study evaluating the efficacy of spevatamig in combination with chemotherapy in first-line PDAC patients. Spevatamig is a novel immunotherapy which has the potential to become the first innate immunity enhancer (I₂E) for a solid tumor indication and is combinable with various anti-cancer therapies.

ABOUT PHANES THERAPEUTICS

Phanes Therapeutics, Inc. is a clinical stage biotech company focused on innovative drug discovery and development in oncology. Currently, it is conducting three Phase 2 clinical trials with spevatamig, peluntamig, and mavrostobart. Both spevatamig and peluntamig are first-in-class bispecific antibodies and have been granted orphan drug and Fast Track designations by the FDA.

The company has built a strong pipeline by leveraging its proprietary technology platforms: PACbody^®, SPECpair^® and ATACCbody^® to develop novel biologics that address high unmet medical needs in cancer.

For more information about Phanes Therapeutics, please visit www.phanesthera.com.

For business development or media inquiries, please contact [email protected] or [email protected], respectively.

SOURCE Phanes Therapeutics, Inc.