S4, E8: Infinimmune – From a Scientific Hunch to an $838M Merck Partnership, with CEO and co-founder Wyatt McDonnell

In this episode, Surani explores the unconventional start-up story of Infinimmune, an antibody discovery company founded in 2022 by five former 10x Genomics scientists. Starting with a scientific hunch that advances in single-cell sequencing were revealing previously overlooked antibody biology, the team went from debating ideas in a tiny California office to raising a $12 million seed round in just three months. Four years later, Infinimmune has raised close to $90 million, built its own pipeline of antibody drugs and signed a multi-target discovery partnership with Merck worth up to $838 million. Surani speaks with co-founder and CEO Wyatt McDonnell about his journey from academia to 10x Genomics, the scientific observations that led him to question what he'd been taught about antibody biology, and why he ultimately decided there was a company to build around them. Wyatt discusses bringing together five former colleagues, raising capital early in his career, building Infinimmune's discovery platform, and how the team earned the trust of Merck. Timestamps 00:00 – From a scientific hunch to an $838M Merck deal02:00 – Infinimmune's human-first approach to antibody discovery04:00 – Wyatt McDonnell's journey from academia to 10x Genomics09:00 – How COVID changed the trajectory of Wyatt's research11:00 – Questioning the textbooks and uncovering overlooked antibody biology13:00 – Turning a scientific observation into a biotech company16:00 – Raising a $12M seed round in just three months17:00 – What investors made of five 10x scientists starting a company together21:00 – Building the platform much faster than expected22:00 – How Infinimmune built credibility with Merck25:00 – Landing a partnership worth up to $838M26:00 – The $75M Series A and what comes next27:00 – Partnerships, M&A, IPOs and thinking about an eventual exit For any comments, questions or feedback you can connect directly with Surani Fernando on LinkedIn or email: raisingbiotech@gmail.com Title music composed by: Yurii Semchyshyn (Coma Media)