Phanes Therapeutics announces US patent granted to its proprietary bispecific antibody technology platform PACbody®

SAN DIEGO, Sept. 16, 2026 /PRNewswire/ -- Phanes Therapeutics, Inc. (Phanes), a clinical-stage biotech company focused on innovative drug discovery and development in immuno-oncology (IO), announced today that the U.S. Patent and Trademark Office (USPTO) has officially granted a patent (Patent No. US12,735,481) for its proprietary, core bispecific antibody technology platform, PACbody^® (PAC = Pairing of Alternative Cysteines). This patent grant marks a significant milestone for Phanes in its foundational bispecific technology and global intellectual property protection.

PACbody^® is a proprietary bispecific antibody construction platform internally discovered and owned by Phanes. It enables the generation of bispecific antibodies that maintain native IgG structures with drug-like CMC characteristics. Bispecific antibodies built on this platform exhibit excellent manufacturability, including stability, high expression, and seamless compatibility with conventional monoclonal antibody commercial manufacturing processes, significantly reducing development, clinical, and manufacturing risks.

Innovative bispecific antibodies developed using the PACbody^® platform have demonstrated robust clinical potential. Most notably, Phanes' core asset spevatamig (PT886) has advanced into Phase II clinical trials and showed positive results, as reported at the ASCO Annual Meeting in May 2026. Spevatamig is a first-in-class native IgG-like bispecific antibody (bsAb) targeting claudin 18.2 and CD47. It was granted by the FDA orphan drug designation (ODD) for the treatment of pancreatic cancer in 2022, Fast Track designation for the treatment of patients with metastatic claudin 18.2-positive pancreatic adenocarcinoma in 2024, and recently, Fast Track designation for the treatment of advanced and metastatic biliary tract carcinoma. 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. Spevatamig is an innate immunity enhancer (I₂E), an emerging class of immuno-oncology (IO) agents. It has the potential to become the first I₂E for a solid tumor indication and is combinable with various anti-cancer therapies.

"We are thrilled that our PACbody^® platform has been granted this U.S. patent," said Dr. Ming Wang, Founder and CEO of Phanes Therapeutics. "PACbody^® is our core technology for overcoming the CMC challenges that typically hindered bispecific antibody development. This patent approval not only validates our top-tier innovative R&D capabilities but also significantly strengthens the protection of our core pipeline's intellectual property. We will continue to leverage this platform to accelerate the delivery of safer and more effective breakthrough therapies to cancer patients worldwide."

ABOUT PHANES THERAPEUTICS

Phanes Therapeutics, Inc. is a clinical-stage biotech company focused on innovative drug discovery and development in immuno-oncology (IO). 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.