Fidji Simo on her life after OpenAI and new startup, ChronicleBio

Fidji Simo has left OpenAI for a very different fight. In early July, the former Instacart CEO stepped away from her role as one of OpenAI’s top executives and moved into a startup called ChronicleBio, where the goal is to use AI to study blood and help explain chronic disease.

Her focus is personal. Simo has Postural Orthostatic Tachycardia Syndrome, or POTS, a condition that can bring fatigue, fainting, nausea and headaches. It’s still considered incurable, even though it affects millions of people. The source notes that Greg Brockman’s wife also has it.

ChronicleBio’s pitch is not to treat every POTS patient as if they were the same case file. The company wants to sort patients into more precise groups based on where their symptoms come from, instead of lumping them together the way Simo says medicine often does now. That matters because it could make drug trials more targeted, and less likely to end in a shrug.

Simo’s argument is that these diseases are too complex for the old approach. They touch the nervous system, the immune system and genetics at once, which makes them a massive data problem. Her point is simple: AI may be most useful when the task is not writing emails or polishing slides, but making sense of the messiest parts of human biology.