Silicon Valley is out for blood—and not just the rejuvenating blood of the young. Biomedical engineers are enthralled by the promise of liquid biopsies, noninvasive tests that detect and classify cancers by identifying the tiny bits of DNA that tumors shed into the bloodstream. Studies at leading cancer centers have already shown the technology’s effectiveness in personalizing treatments after diagnosis. Now startups are selling VCs a vision of cheap, surgery-free cancer screening even before symptoms appear.
Andreessen Horowitz, Google Ventures, Verily, and others have invested $77 million in Freenome, which uses machine learning to pinpoint immune-system responses that may indicate the presence of cancer. Freenome’s most prominent rival, Grail—which plans to harness next-generation gene sequencing to directly measure cancerous genomic alterations in the blood—raised $1.2 billion last year from ARCH Venture Partners. Both companies are racing to make the first DNA-detecting blood test to reveal disease in its earliest stages. It’s the holy—well, you know—of cancer care.
If this scientific sprint is giving you Theranos flashbacks, it should. Critics believe that even with the aid of low-cost genetic sequencing and high-powered algorithms, liquid biopsy detection is still years away from being patient-ready. The startups have shared scant data so far. (Grail has begun enrolling 130,000 patients in two huge trials, but it won’t have results for a few years.) Having secured massive infusions of funding, it’s not money holding these blood unicorns back, it’s basic biology.
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