PRESS RELEASE
Photys Therapeutics and Polymed Biopharmaceuticals Announce the Initiation of a Phase I Clinical Trial of PHT-776/HPB-143, an Oral IRAK4 PROTAC Degrader
August 13, 2026
Polymed Biopharmaceuticals is dedicated to developing optimized PROTACs and Degrader Antibody Conjugates (DACs) engineered to deliver an improved therapeutic index compared with first-generation protein degraders. By combining advanced discovery technologies with deep expertise in targeted protein degradation and conjugate design, Polymed is building a pipeline of innovative therapies for patients with cancer and autoimmune diseases worldwide. Headquartered in Hangzhou, China, with operations in Cambridge, Massachusetts, Polymed is a member of the Johnson & Johnson JLABS innovation network.
For more information, please visit www.polymedbiopharma.com/en.
Waltham, Massachusetts, USA, and HANGZHOU, Zhejiang, China – August 13, 2026
Photys Therapeutics, Inc. (“Photys”), a proximity-based therapeutics company, and Polymed Biopharmaceuticals, Inc. (“Polymed”), a global biotech company focused on creating best-in-class PROTACs (proteolysis targeting chimera) and DACs (degrader antibody conjugates) therapeutics, today announced the initiation of a Phase I clinical trial evaluating PHT-776/HPB-143, an investigational IRAK4 PROTAC candidate.
PHT-776/HPB-143 is an oral IRAK4-targeted PROTAC designed to selectively and efficiently degrade IRAK4, a central driver of inflammatory signaling implicated in a wide range of autoimmune and inflammatory diseases including hidradenitis suppurativa, atopic dermatitis, psoriasis, and ulcerative colitis. In preclinical studies, PHT-776/HPB-143 demonstrated high oral bioavailability, potent efficacy at low doses across multiple disease models, and a broad preclinical safety window with no observed cardiovascular effects, differentiating it from publicly disclosed IRAK4 PROTAC programs.
PHT-776 is being developed under a licensing agreement established in 2025 in which Polymed granted Photys the exclusive rights to develop and commercialize PHT-776/HPB-143 outside of Greater China and Southeast Asia. Polymed Chief Business Officer Brent Meadows will also serve as an observer to the Photys Board of Directors.
“Photys is excited to have partnered with Polymed to jointly advance this potentially best-in-class IRAK4 degrader, PHT-776/HPB-143, into Phase 1 clinical trials. We are looking forward to the clinical data emerging over the next 12 months,”
KAZUMI SHIOSAKI, EXECUTIVE CHAIR OF THE PHOTYS BOARD OF DIRECTORS
“The initiation of this first-in-human trial represents an important milestone in the development of PHT-776/HPB-143 and validates the success and continued advancement of Polymed’s optimized protein degradation platform,". "We look forward to evaluating the safety, pharmacokinetic profile, and clinical potential of this novel IRAK4 degrader.”
JASON XIANG, CHIEF EXECUTIVE OFFICER OF POLYMED
The Phase I trial will comprise single-ascending and multiple-ascending dose cohorts. The initial cohorts of healthy participants have been dosed at Huashan Hospital, affiliated with Fudan University. Huashan Hospital is consistently ranked in the top tier of Chinese hospitals and is recognized for its international partnerships in successfully conducting clinical trials in China.
ABOUT PHOTYS THERAPEUTICS
Photys Therapeutics, Inc. is a proximity-based therapeutics company with expertise across multiple approaches to targeted protein modulation. Through its proprietary PHICS™ and tPRIME™ platforms, together with expertise in PROTACs, Photys is building a pipeline of differentiated therapies for autoimmune, inflammatory, oncology, and cardiometabolic diseases. Photys is based in Waltham, Massachusetts.
For more information, please visit www.photys.com.