May 21, 2014 | by Hiu Chung So
For lung cancer patients whose tumors are resistant to a class of chemotherapy called tyrosine kinase inhibitors (TKI), a drug called cabozantinib may be able to undo that resistance, according to a new City of Hope study.
The results will be presented at the American Society of Clinical Oncology's annual meeting on June 3.
"Previous studies have shown that in patients with nonsmall cell lung cancer linked to a EGFR gene mutation, the proteins MET and VEGF promote tumor growth and make it resistant to TKI chemotherapy," said Karen Reckamp, M.D., M.S., co-director of the Lung Cancer and Thoracic Oncology Program and first author of the abstract. "Because cabozantinib can block both of these proteins, we want to see if can can reverse that drug resistance as well."
For this phase II trial, Reckamp and her colleagues studied 35 patients with advanced, EGFR-mutant nonsmall cell lung cancer whose disease had progressed despite TKI therapy. The patients were given 40 milligrams of cabozantinib in addition to 150 milligrams of TKI drug erlotinib daily for 28 days, and were then examined to determine whether their tumors had responded to the combination therapy.
In the abstract, Reckamp reported that the cabozanitinib-erlotinib combination therapy significantly slowed tumor growth, as measured by a slower doubling time (the amount of time it takes a tumor to double in size) compared to before the treatment. Additionally, four patients showed partial remission of their cancer while on cabozantinib-erlotinib therapy. Based on these findings, the researchers noted that the cabozantinib-erlotinib regimen has potential benefits for patients with EGFR-mutant nonsmall cell lung cancer that should be further investigated.
Cabozantinib is currently approved for medullary thyroid cancer and is also being tested in clinical trials for melanoma, brain tumors, and liver, breast, ovarian and prostate cancers.
Learn more about lung cancer research at City of Hope.
Research reported in this publication was supported by the National Institutes of Health under grant numbers N01CM2011-00038 and U01CA062505. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
The abstract (#132255) is available ahead of the meeting on ASCO's website.