Poplar Therapeutics, a Cambridge, MA-based clinical-stage immunology company, raised $45M in Series A extension funding.
Poplar Therapeutics just delivered the kind of raise that turns heads across the biotech landscape. A $45M Series A extension just landed, bringing the total Series A haul to $95M
Poplar Therapeutics just delivered the kind of raise that turns heads across the biotech landscape. A $45M Series A extension just landed, bringing the total Series A haul to $95M. Janus Henderson Investors led the round, with RA Capital stepping in as a new investor and continued backing from SR One, Vida Ventures, and affiliates of ArrowMark Partners. Serious capital from serious players who know the difference between noise and signal.
Behind the wheel is CEO Chip Baird, with Founder and CSO Tony Yao, M.D., Ph.D. driving the science that started this whole story. If you spend any time around the Boston and Cambridge biotech ecosystem, you know the formula is rarely luck. It is usually a sharp thesis, disciplined execution, and investors who understand when a scientific bet is worth pressing.
The company is developing PHB-050, a next generation anti-IgE antibody designed with a triple action approach aimed squarely at IgE mediated diseases. Food allergies, allergic asthma, atopic dermatitis. Conditions where IgE levels can make life complicated fast and where current therapies do not reach every patient who needs help.
PHB-050 is being studied with a clear objective: rapidly drive IgE levels toward zero. That sentence may read quietly on paper, but in immunology circles it carries weight. IgE sits at the center of allergic responses, and shifting that biology could reshape how these conditions are managed for millions of patients who still cycle through limited options.
The company launched earlier this year with a $50M Series A and stepped into the arena with a Phase 1 clinical trial already underway. Data from that study is expected in the second half of 2026. This new $45M extension is the fuel to keep pushing PHB-050 forward through the clinic and deeper into the science.
Poplar trees grow fast, stand tall, and build deep roots. That is the kind of growth you want in biotech. Strong science underground, steady capital above it, and a team that knows how to weather the long seasons between discovery and impact.
Credit to CEO Chip Baird, CSO Tony Yao, M.D., Ph.D., and the leadership team for building something investors clearly believe in. Respect as well to Janus Henderson Investors, RA Capital, SR One, Vida Ventures, and ArrowMark Partners for recognizing the opportunity and leaning in. Biotech does not reward hype. It rewards patience, precision, and people willing to fund the long game. Poplar Therapeutics just added more runway to do exactly that.









