Sanofi to acquire Dren Bio's bispecific myeloid cell engager for deep B-cell depletion, broadening immunology pipeline

by Simeon George, MD | CEO & Managing Partner

We’re excited to share big news: Sanofi has agreed to acquire Dren Bio’s lead bispecific myeloid cell engager program, DR-0201 for $600 million upfront and up to $1.3 billion in contingent milestone payments.*

This is a major achievement for Dren — and for SR One — and reflects the strength of our strategy: backing high caliber founders pursuing breakthrough science and supporting them through key moments of company building.

We first partnered with Dren in 2020, leading the Series A and continued to support the company through subsequent rounds. Our belief was rooted in two things:

·       A trusted partnership with CEO Nenad Tomasevic, PhD, a repeat founder who previously built Allakos Inc. (NASDAQ: ALLK)

·       A differentiated scientific thesis around engaging myeloid cells for pathogenic cell depletion, which ultimately became the foundation for DR-0201

 Since then, Dren has executed with speed and precision:

·       Advanced several programs from idea to clinical trials

·       Secured impactful partnerships with Pfizer (2021) and Novartis (2024), worth $175 million upfront and up to $3.85 billion in contingent milestone payments.

·       Recruited experienced talent — including Chief Operating Officer/Chief Business Officer Amit Mehta PhD, brought in through SR One’s CEO Summit and who were instrumental in the Novartis and Sanofi deals

The lead program, DR-0201, is a first-in-class antibody designed to deplete harmful B cells by engaging myeloid cells — a new and promising approach for treating autoimmune diseases. It has shown encouraging results in both lab models and early human studies, and we believe it offers the potential to be best-in-class.

Dren’s pipeline also includes:

·       DR-01, now in trials for rare blood cancers and autoimmune conditions

·       DR-0202, expected to enter clinical studies in 2025 for the treatment of solid tumors

This outcome is a powerful example of SR One’s model at work: invest early, partner closely, and help turn great science into real-world impact. We’re incredibly proud to have played a hands-on role in Dren’s journey- from the early stages through this transformative transaction — and are excited for what comes next.

*This transaction has not yet closed and remains subject to customary closing conditions. There can be no assurance that the transaction will close on the terms or timing contemplated herein. No investor should make an investment decision on the basis of this pending transaction.

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