Investing in IDRx

HIV ravaged entire communities before antiretroviral cocktail therapies helped turn the tide. Cocktail therapies combine multiple drugs: Some hit parts of the replication machinery the virus uses to make copies of itself, others block its ability to attack and enter our cells. By pursuing multiple lines of attack in parallel, combination therapies keep viral levels low and leave fewer opportunities for the virus to mutate and develop therapeutic resistance. This approach transformed an HIV diagnosis from a death sentence into a chronic, manageable condition.

I met serial biotech entrepreneur Alexis Borisy years ago when I was starting out as a first-time founder and CEO. By then he had already founded a couple of companies himself and he became a friend and advisor. Over the years, I’ve learned two important things about Alexis. First, the fedora is standard issue wear. And whenever he poses a broad sweeping question — delivered with dramatic flourish — it’s a good bet that there’s a new company idea on the other side of it.

“Where’s the Amazon for delivering low-cost, innovative drugs?” Enter EQRx.

“Why don’t we attack cancer like we fight viruses?” The era of precision medicine has revolutionized the treatment of certain cancers. By targeting a specific mutation (BCR-ABL) Gleevec can effectively cure chronic myeloid leukemia. But a single knockout punch rarely works. Like viruses, most cancers develop multiple escape mutations — they learn to bob and weave — and eventually evade precision therapies. And you have to wallop the cancer while leaving the person standing; cancers are wilier opponents than viruses because they originate from within us. So where are the precisely tailored jab-cross-hook combinations for cancer? In comes IDRx.

But this is not the first time Alexis has asked this question. In fact, it’s one of the first questions he asked: In 2000 he founded his first company CombinatoRx to create synergistic combination therapies for cancer. The company couldn’t fully deliver on its promise, but as my partner Marc Andreessen says, ”there are no bad ideas in tech, only bad timing.” Since then, Alexis has been traversing the idea maze to find the right moment and momentum. He hasn’t been traveling alone: Ben Auspitz, IDRx’s co-founder and CEO, a seasoned biotech executive himself, began his startup career at CombinatoRx.

This is good timing. Two decades ago, CombinatoRx used robotically-enabled brute force to try millions of potential drug combinations. Today we have a more sophisticated understanding of tumor biology. With advances in genomics and now-available drug engineering capabilities, IDRx aims to pioneer intelligently designed combination therapies that hammer driver mutations, cover escape pathways and safely enable use earlier in the course of disease where there is the highest potential for prolonged, durable responses to cancer treatment. Jab-cross-hook.

In addition to Alexis and Ben, IDRx’s founding team reflects its ambitions. Harvard oncologist George Demetri is a world-renowned expert in gastrointestinal stromal tumor (GIST), the company’s first targeted indication. Nicholas Lydon is the precision medicine pioneer that developed Gleevec. Robert Forrester is a repeat company-builder and another CombinatoRx alum. IDRx has also assembled a deep bench of drug hunters. Collectively this team has been involved with the discovery, development and commercialization of more than 10 approved drugs.

IDRx is off to a running start. The company is launching with $122 million to transform cancer care through intelligently designed combination therapies. The company’s expanding pipeline includes two clinic-ready small molecules, IDRX-42 (from Merck KGaA) and IDRX-73 (via Blueprint Medicines), designed to hit separate genetic drivers and resistance mutations in GIST — and IDRx is already a clinical-stage company having initiated a Phase 1 trial. a16z is thrilled to co-lead this financing with Casdin Capital, with participation from oncology experts Nextech Invest, Forge Life Science Partners and other undisclosed investors.


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