Boulder, Colorado-based Biodesix is developing diagnostics that use a patient's molecular profile to detect and monitor such diseases as lung cancer, and to help doctors predict whether a treatment will be successful. It's the most recent biotech startup for co-founder David Brunel, 60.

--As told to Bob Diddlebock

Biodesix grew out of my background in using high-throughput techniques to analyze different biological molecules--genes and proteins. I connected with [Biodesix co-founder] Heinrich Röder, a theoretical physicist from Oxford. One of his specializations is in using advanced analytics in machine-learning techniques to look at large data sets and extract meaning from them.

When a patient presents with metastatic cancer, the usual treatment is chemotherapy, which is cytotoxic. That means it uses drugs that kill all the dividing cells in the body. But guess what--those drugs help maybe just a third, and sometimes fewer, of these patients. And they have horrible side effects.

Wouldn't it be nice to know in advance whether a patient will respond to a drug? Rather than doing clinical observation or patient interrogation, you actually look at the biological information from that patient using sophisticated techniques to get a more accurate picture. That's personalized medicine or precision medicine: the right drug to the right patients at the right time.