By Jennifer King, Director of Science and Research at Lung Cancer Alliance
Last week, I blogged about some of the research presented at the 2015 ASCO Meeting – particularly the promise of immuno-oncology. Today, I’m going to focus on another topic that is a very hot right now: precision medicine. President Obama announced a new Precision Medicine Initiative during the state of the union address. The government is defining precision medicine as “an emerging approach for disease prevention and treatment that takes into account people’s individual variations in genes, environment, and lifestyle.”
Precision medicine, formerly called personalized medicine, is exploding in lung cancer as well as many other cancers. There are countless targeted therapies, drugs that work on specific genetic variations (changes/mutations), in company drug pipelines. For most clinical trials of these drugs, you are first tested to see if your tumor has the right biomarker (the variation) – before you can go on the drug.
Many new advances in targeted therapies were presented last week at the ASCO meeting. Note that in all of the studies referenced below, the patients had advanced/metastatic lung cancer.
There are already multiple drugs available for treating lung cancer with EGFR and ALK changes, but many people develop resistance to these therapies. This resistance is typically because the tumor develops another variation/mutation that prevents the drug from working. Drugs are now being developed to target these resistance mutations.
Data on some new EGFR targeted therapies were presented at the meeting. Rociletinib worked in close to half of the patients who had a known EGFR resistance mutation. Notably, this was true whether the EGFR test was done from a regular tissue biopsy or from a “liquid biopsy” (a blood test). AZD9291 had good results in an early trial as a first-line EGFR inhibitor and a Phase III trial comparing it to first-line Tarceva or Iressa (gefitinib) is now underway.
For patients with ALK changes in their lung cancers, there are also new drugs in development. Data was presented on alectinib showing that roughly half of patients who were already resistant to crizotinib responded to alectinib (and if you include those who had ‘stable’ tumors that were not growing, it was ~80% of patients who benefitted from the drug).
Importantly, more than half the patients in the trial had lung cancer that had metastasized to the brain and the drug also worked on many of the tumors in the brain. A Phase III trial is now ongoing comparing alectinib to crizotinib, as well as an expanded access study for patients whose cancer is resistant to crizotinib. Another new ALK inhibitor, brigatinib, that may also work on brain metastases is in a Phase II clinical trial.
Increasingly, targeted therapies are being used for a much smaller population of patients. There are many gene changes that are only present in less than 5% of lung cancer patients, but drugs may still be quite effective for the patients that do have these changes. Some examples that had promising results presented at the meeting were a combination of Tafinlar (dabrafenib) and Mekinist (trametinib) for patients with mutations in a gene called BRAF (common in melanoma) and Cometriq (cabozantinib) for patients with changes in RET, and likely also MET and ROS1.
The important things to remember here are not the specific drugs names and studies. There are a few key take-aways:
- Every lung cancer is different and treatment decisions need to be made precisely for you, your cancer and your lifestyle and values
- There are many new drugs coming soon and they each will likely only work for a small percentage of people. It is more important than ever to have conversations with your care team about what the options are and what tests are needed to determine the best treatment path for you.
Also, I want to point out that none of this important research could have been done without patients enrolling on clinical trials. Clinical trials are very important and definitely a path to consider. My next blog will be about some of the new trials out there and how clinical trials are now being designed in smarter, more effective ways.