Phase 1 clinical trial underway for PHB-050, a next-generation IgE depleter, with data expected in 2H26

Series A financing led by SR One, Vida Ventures, and Platanus

Poplar to present at the 44^th Annual J.P. Morgan Healthcare Conference on Thursday, January 15 at 11:00AM PT

Poplar Therapeutics, Inc. announced its launch today highlighting its $50 million Series A financing led by SR One, Vida Ventures and Platanus. Previously known as Phylaxis Bioscience, Poplar Therapeutics is a clinical-stage immunology company developing a new class of anti-IgE therapy to treat food allergy and other atopic conditions.

“We are launching Poplar Therapeutics with the goal of transforming the treatment of atopic diseases. PHB-050 has the potential to be best-in-class and help millions of patients in need of effective treatment options,” said Chip Baird, chief executive officer of Poplar Therapeutics. “The ongoing Phase 1 will provide important data on safety, pharmacokinetics and PHB-050's potential to rapidly drive IgE levels toward zero. We expect to have the results of our Phase 1 study during the second half of 2026.”

Despite the availability of omalizumab (Xolair®), a first-generation anti-IgE therapy, millions of patients with atopic diseases such as food allergy, allergic asthma and atopic dermatitis lack effective treatment options, representing a significant unmet medical need. Patients with elevated IgE levels are ineligible for or do not adequately respond to currently available treatments.

“We have incorporated the last 20 years of learnings from the field into the design of PHB-050,” said Tony Yao, M.D., Ph.D., founder of Poplar Therapeutics. “Preclinical data suggest PHB-050 can not only bind and block soluble IgE but can also rapidly drive total IgE toward zero. With PHB-050, our goal is to enable the effective treatment of all patients, including those with highly elevated IgE levels who cannot be treated with existing therapies.”

Mr. Baird was appointed president and CEO of Poplar Therapeutics in October 2025 and brings over 20 years of executive operating experience leading highly innovative, patient-focused companies. Most recently, Mr. Baird served as CEO of 2seventy bio, leading through its successful sale to Bristol Myers Squibb. The Poplar leadership team also includes René van der Merwe, M.D., as chief medical officer and Vicki Eatwell as chief financial officer. Prior to joining Poplar, Dr. van der Merwe previously held leadership roles at Aiolos Bio and DBV Technologies. Ms. Eatwell most recently served as CFO of 2seventy bio.

Poplar's Board of Directors brings deep experience across all aspects of drug discovery, drug development and operations:

• Dan Welch (Board Chair), former CEO of InterMune, experienced Board member
• Joanne Waldstreicher, M.D., former CMO, Johnson & Johnson
• Jill Carroll, Partner, SR One
• Helen Kim, Senior Managing Director, Vida Ventures
• Tony Yao, M.D., Ph.D., Founder and Chief Scientific Officer
• Chip Baird, President and CEO, Poplar Therapeutics

Poplar Therapeutics will be presenting at the 44^th Annual J.P. Morgan Healthcare Conference in San Francisco on Thursday, January 15 at 11:00am PT.

About PHB-050

More than seven million patients with atopic conditions have high IgE levels, with approximately three million considered ineligible for or resistant to current standard therapies. In food allergy, approximately 50% of patients are classified as having high IgE levels.

PHB-050 is a novel, next-generation anti-IgE antibody designed to treat multiple atopic diseases, including food allergy, asthma and atopic dermatitis with potential application for select orphan immunology and inflammatory diseases. Its unique triple-action mechanism is designed to not only block IgE from binding to mast cells that trigger allergic reactions, but also to rapidly reduce circulating IgE and inhibit its production.

About Poplar Therapeutics

Poplar Therapeutics, Inc. is a clinical-stage immunology company developing a new class of anti-IgE therapy to challenge convention in treating allergic disorders, which was incorporated in 2024. Its lead program, PHB-050, is a next-generation anti-IgE antibody with a unique triple-action design currently being studied in atopic diseases. Poplar is pursuing the bold idea that IgE can be rapidly driven toward zero, with the goal of helping people with IgE-mediated conditions move from fear toward freedom.

View source version on businesswire.com: https://www.businesswire.com/news/home/20260107745236/en/

“We are launching Poplar Therapeutics with the goal of transforming the treatment of atopic diseases. PHB-050 has the potential to be best-in-class and help millions of patients in need of effective treatment options,” said Chip Baird, CEO.