FDA Approves Osimertinib Blood-Based T790M Companion Diagnostic Test
On September 29, the U.S. Food and Drug Administration (FDA) approved a blood-based companion diagnostic for osimertinib (Tagrisso). The companion diagnostic for osimertinib is the only FDA-approved and clinically validated companion diagnostic test that uses either tissue or a blood sample to confirm the presence of a T790M point mutation in patients with metastatic epidermal growth factor receptor (EGFR) mutation–positive non–small cell lung cancer (NSCLC), who have had disease progression on or after EGFR tyrosine kinase inhibitor therapy.
The approval provides a new, noninvasive option to identify patients with metastatic EGFR T790M mutation–positive NSCLC, ensuring that those patients who may not be suitable for biopsy procedures have an opportunity to be tested. Blood-based testing for the presence of the mutation is recommended only when a tumor biopsy cannot be obtained. Patients who test negative for the T790M mutation with the blood-based test and their physicians should reevaluate the feasibility of tissue-based testing to confirm the presence of the EGFR T790M mutation.
The companion diagnostic, cobas® EGFR Mutation Test v2, was developed by Roche Molecular Systems. The test enables identification of patients who have the T790M mutation at disease progression and is initially available through Baystate Health, Carolinas HealthCare System, Laboratory Corporation of America Holdings (LabCorp), and PhenoPath.
“Blood-based testing has the potential to rapidly identify patients eligible for targeted therapy who may not be eligible for biopsy. Availability of this blood-based test may help aid treatment decisions,” said Balazs Halmos, MD, Montefiore Medical Park, Albert Einstein College of Medicine.
“The availability of an FDA-approved, blood-based companion diagnostic is a tremendous step forward for patients with lung cancer in need of a high-quality test that provides results with a rapid turnaround time. This development offers an important option for the identification of the T790M mutation in patients with metastatic EGFR mutation–positive NSCLC who have progressed on an EGFR [tyrosine kinase inhibitor], for whom a tissue biopsy may not be feasible,” said Andrew Coop, Vice President, US Medical Affairs, Oncology, AstraZeneca. “Delivering targeted therapies, such as [osimertinib], to the right patients at the right time, demonstrates our commitment to testing and quality companion diagnostics.”
Nearly two-thirds of cases of progression with first-generation EGFR tyrosine kinase inhibitors are related to an acquired EGFR T790M mutation—for which there have been limited treatment options in the past. Osimertinib is the only FDA-approved targeted medicine for the treatment of patients with metastatic EGFR T790M mutation–positive NSCLC who have had disease progression on or after an EGFR tyrosine kinase inhibitor and was approved by the FDA in November 2015.
This indication was approved under accelerated approval based on tumor response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trials.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
