Precision medicine hasn’t lived up to its initial promise, yet. This is partly because identifying rare genetic markers person-by-person is a hugely complex and time-consuming task.

“I look at precision medicine, especially as it relates to genomics, to be like the old Apple IIe computer,” Bryan said. “I had the Apple IIe growing up, and it didn’t do much other than maybe some simple video games and basic calculations. But you can see now how computers have changed our lives completely. It took people seeing past what the Apple IIe wasn’t at the time, and I think we are in the same place with precision medicine and genomics today. We are going to look back on what we are doing today and wonder at how simplistic we were being, trying to look for single markers to match to a really limited cadre of chemotherapy drugs. I think in the future we are going to get really fast at finding patterns of genomic markers and use this information to match to an expanding pipeline of medications.”

Today, drugs designed to target rare genetic markers like NTRK fusions and RET fusions, proteins made by aberrant gene fusions, are resulting in patient response rates of over 80 percent. These drugs may only work for a small number of cancer patients, but for those patients they work really well. The more of these rare genetic markers that we can identify, the closer we will get to effective precision cancer treatments for a great number of people.

Matching Drugs to Your Own Cancer DNA

As Bryan spends his time across both the laboratory and the clinic, he sees breakthroughs in terms of discovering new genetic markers and cancer drug targets reach real-life patients.

“Every day we meet a patient in the clinic who has a really interesting or rare genetic marker for which we try a medication that works really well,” Bryan said. “This is what gets me up in the morning and excited to go to work. My hope is that over the next decade, the fraction of those patients in our clinic will grow.”

Bryan recently had a patient enter his clinic with a very aggressive anaplastic thyroid tumor. The median survival for patients with this incurable type of cancer is only 3-6 months. It’s also a fairly chemo-resistant disease.

“There’s not much that works for this cancer,” Bryan said. “This young gentleman came into our clinic with anaplastic thyroid cancer having tried two different traditional chemotherapies without success. While trying to keep our expectations realistic, we gave whole genome sequencing a go with this patient.”

Bryan’s group discovered two different genetic markers that they could target with drugs for this patient. They found a BRAF mutation, for which there are drugs that have been used in melanoma patients, and an over-expression of programmed death-ligand 1 (PD-L1), which indicated that an immune-based therapy might also be beneficial for this patient.