The US Food and Drug Administration (FDA) has approved a new drug for patients with a certain type of non-small cell lung cancer (NSCLC) who have progressed after an EGFR tyrosine kinase inhibitor (TKI) therapy.
Tagrisso (osimertinib, AstraZeneca) is a third generation EGFR TKI designed to inhibit both EGFR sensitizing and EGFR T790M resistance mutations. The drug is to be administered once-daily (80 mg) for the treatment of patients with EGFR T790M mutation-positive NSCLC after progression on an EGFR TKI therapy. Tagrisso is the first and only approved medicine in the US with this indication, and researchers believe it may become a new standard of care for patients with such disease.
Approval of the new medicine is based on data from a randomized, phase III trial. Tagrisso significantly improved progression-free survival (10.1 months) compared with platinum-based doublet chemotherapy (4.4 months) in patients with EGFR T790M-positive NSCLC (hazard ratio, 0.30; 70% risk reduction; 95% Confidence Interval [CI]: 0.23-0.41; P < .001).
In an additional post-hoc subgroup analysis of patients with measurable central nervous system lesions, Tagrisso produced an object response rate of 57% (95% CI; 37%-75%) compared with a 25% objective response rate from chemotherapy (95% CI: 7%-52%).
Common adverse events associated with Tagrisso include diarrhea, rash, dry skin, nail toxicity, and fatigue. Observed serious adverse events as a result of taking Tagrisso include interstitial lung disease or pneumonitis, heart rate-corrected QT, cardiomyopathy, and keratitis. Women who are pregnant are advised not to take Tagrisso.
According to researchers, Tagrisso may become a standard of care for patients who are tested for and show T790M-positive mutations. “Testing for EGFR T790M should be a critical next step in patients who develop acquired resistance after first-line EGFR TKI therapy,” said H Jack West, MD, medical oncology, medical director, thoracic oncology program, Swedish Cancer Institute, in a press release (March 31, 2017).
Tagrisso was granted Fast Track, Breakthrough Therapy, and Priority Review designations by the FDA and received Accelerated Approval for this indication in 2015 after data showing tumor response rate and duration of response. – Zachary Bessette