ProLynx Secures $70M Series A to Advance Ultra-Long-Acting Obesity and Metabolic Therapies
ProLynx, a San Francisco-based biotechnology company, has secured a $70 million Series A financing to advance a portfolio of ultra-long-acting medicines targeting obesity and related metabolic diseases. The funding round, announced in December 2025, positions the company to accelerate development of therapies designed for monthly and quarterly dosing, moving beyond the weekly regimens common in current treatment paradigms and potentially improving adherence, tolerability, and long-term outcomes for patients.
The Series A round was co-led by 5AM Ventures, OrbiMed, and Monograph Capital, three leading life sciences venture investors with extensive experience backing innovative biopharmaceutical platforms and therapeutic pioneers. Additional participation further strengthened the company’s investor base, bringing together expertise in late-stage drug development, metabolic disease commercialization, and long-acting therapeutic technologies.
ProLynx’s proprietary approach centers on a platform capable of extending the half-life of therapeutic molecules, enabling controlled and sustained release that maintains therapeutic levels over longer periods. This technology has demonstrated proof-of-concept in oncology settings and now underpins an effort to develop a pipeline of extended-duration peptide therapeutics for obesity and metabolic disease.
The 2025 financing coincided with a leadership transition, as biotech veteran Chris Boulton was appointed Chief Executive Officer. Boulton brings more than 25 years of global pharmaceutical experience, including leadership roles focused on obesity and metabolic therapies at major industry players. His expertise is expected to guide ProLynx’s portfolio development and clinical strategy as it moves toward IND enablement and proof-of-concept studies for its lead candidates.
ProLynx was founded by Dr. Daniel Santi and Dr. Gary Ashley, scientists with deep roots in drug delivery and sustained-release chemistry. With the new funding, Santi transitioned to Chief Technical and Scientific Officer, focusing on advancing the scientific engine behind ProLynx’s pipeline, while Ashley continues to leverage his expertise in protein and peptide chemistry to drive the company’s technological evolution.
The choice to pursue ultra-long-acting therapies comes amid growing interest in next-generation pharmacokinetics for chronic conditions. Current obesity treatments have shifted toward peptide-based agents, but many require frequent dosing and can be associated with side effects that limit adherence. ProLynx believes its half-life extension platform can enable drugs that maintain effective levels with less frequent administration, enhancing patient comfort and real-world use.
Lead programs in ProLynx’s pipeline include a long-acting version of semaglutide, aimed at once-monthly or quarterly dosing. The company also plans to explore other peptide analogs, including dual-acting molecules that combine GLP-1 and GIP receptor agonism, alongside additional candidates designed to provide broad coverage across metabolic mechanisms.
Investor confidence in ProLynx’s platform is tied to the large market opportunity in metabolic disease therapies, where demand continues to grow for patient-centric treatments that improve quality of life while easing administration burdens. With obesity and metabolic conditions affecting large and diverse populations, less frequent dosing represents a compelling clinical and commercial value proposition.
The backing of 5AM Ventures, OrbiMed, and Monograph Capital brings substantial financial resources and strategic insights to ProLynx at a critical stage. These investors have experience in scaling biotech companies through clinical milestones, regulatory engagement, and commercialization planning, underscoring their belief in the company’s technical foundation and long-term potential.
ProLynx’s $70 million Series A financing marks a major milestone for the company and reflects broader investor interest in next-generation therapeutic modalities that aim to reshape chronic disease treatment. As ProLynx advances its research, clinical preparation, and talent recruitment under its new leadership, the company aims to leverage its extended-duration platform to bring transformative metabolic medicines to patients worldwide.
