Andy Walker

Most biotechs want to silence the immune system when it misbehaves. Andy Walker helped start a company built on the opposite idea: teach it to behave. GentiBio, which he co-founded in 2020, engineers regulatory T cells - the immune system's own peacekeepers - to do their job with precision. The pitch is not suppression. It is tolerance, re-installed.

Today Walker runs that company. He was named President and CEO of GentiBio in 2024, the third title he has held there. He started as Chief Technology Officer, the founder whose job was to figure out how you actually make a living medicine at scale. From there he became President and Chief Operating Officer, and then, when the top seat opened, he took it. Founders rarely complete that climb. The skills that launch a company are not the skills that run one, and the person who builds the manufacturing process is not usually the person handed the whole P&L. Walker is both.

The science is genuinely strange in the best way. Regulatory T cells - Tregs - are the cells that tell the rest of the immune system to stand down. In autoimmune disease, that signal breaks, and the body attacks its own tissue: the pancreas in type 1 diabetes, the gut in Crohn's, the joints, the skin. GentiBio's engineered Tregs, or EngTregs, combine Treg biology with antigen receptor engineering, borrowing the chimeric antigen receptor (CAR) trick from cancer therapy to aim the cells at exactly the tissue under attack.

The company's own framing is sharper than most marketing: the cells are engineered to be independent of the inflamed environment they are sent into. A normal Treg dropped into a war zone can lose its identity and turn unstable. GentiBio's bet is that its cells hold their line regardless. That stability, the founders argue, is the difference between a nice idea and a durable medicine.

The lead asset, GNTI-122, is an EngTreg aimed at recently diagnosed type 1 diabetes. It cleared FDA acceptance of its investigational new drug application and moved toward the clinic, with key readouts anticipated in the years following. If it works, it would not manage diabetes. It would aim to functionally cure it.

Walker did not arrive at GentiBio as a pure scientist or a pure dealmaker. He arrived as the person who knows how the medicine gets made. Before co-founding the company he was Chief Executive Officer of Jewel Biotherapeutics. Before that, he was Senior Vice President of Technical Operations at Juno Therapeutics, the Seattle cell-therapy pioneer, where he oversaw process development and GMP manufacturing for cellular therapeutics and protein biologics. He also held senior leadership roles, including general manager work, at AGC Biologics.

That background matters more than it sounds. Cell therapy lives or dies on manufacturing. You can have brilliant biology and still fail because you cannot reliably make the cells, batch after batch, to a standard a regulator will accept. Walker spent years on exactly that problem. When GentiBio needed a co-founder who could turn a licensed discovery into a manufacturable product, his resume read like a checklist.

GentiBio launched in 2020 with $20 million in seed funding led by OrbiMed, the Novartis Venture Fund and RA Capital Management. Walker co-founded it alongside Adel Nada and Chandra Patel, stitching together licensed technology from Seattle Children's Research Institute, the Benaroya Research Institute at Virginia Mason, and Israel's MIGAL Galilee Research Institute. The company set up R&D in the Boston area and planted manufacturing roots back in Seattle - Walker's home turf.

The name itself is a small tell about the founders' worldview. GentiBio comes from Latin meaning, roughly, "a congregation of peoples" - a nod to building from many sources, many institutions, many disciplines. For a company assembled from three research institutes on two continents, it fits.

In 2021 came the big round: a $157 million Series A led by Matrix Capital Management, with Avidity Partners, the JDRF T1D Fund and returning seed backers joining. The headcount plan jumped from roughly 17 people toward 90. In 2022, Bristol Myers Squibb signed on to a collaboration to develop cell therapies for Crohn's disease and other conditions - the kind of validation that tells the rest of the industry a platform is real.

The official bio gives him away. Walker is an avid fly fisherman who would rather be on a boat or in the mountains than almost anywhere else, and he keeps strong ties to the University of Washington, where he earned his undergraduate degree in chemical engineering before heading to UC Berkeley for his PhD. And then there is the line his own company saw fit to print: "he also thinks he is funny, but his coworkers tend to disagree."

It is a small, human detail in a field that usually scrubs them out. Biotech bios tend to read like patent filings. Walker's includes a joke about whether his jokes land. That tells you something about the operator - and maybe something about why people followed him from CTO to CEO.

The history of immune-disease treatment is largely a history of turning the dial down: steroids, broad immunosuppressants, drugs that calm the whole system and leave you exposed. Engineered Tregs propose something more surgical - restore the specific peacekeeping signal that broke, leave the rest of the immune system intact. It is early, it is unproven at scale, and it is enormously hard to manufacture. Which is precisely why a company chasing it wanted a chemical engineer who has spent his career making difficult cells reproducibly, sitting in the CEO chair.

Walker is the rare founder who can speak to investors about a functional cure in the morning and argue about GMP batch records in the afternoon. The next few years - the GNTI-122 readouts, the BMS work, the platform's first real test in patients - will decide whether the bet pays off. He has put a career into being ready for that test.