Osimertinib gets EU approval for non-small cell lung cancer4 Feb 2016
The European Commission has granted conditional marketing authorization for AZD9291, osimertinib 80mg once-daily tablets for the treatment of adult patients with locally advanced or metastatic epidermal growth factor receptor (EGFR) T790M mutation-positive non-small cell lung cancer (NSCLC).
Osimertinib is indicated for patients with T790M mutation-positive NSCLC, irrespective of previous treatment with an EGFR tyrosine kinase inhibitor (TKI).
Osimertinib targets mutations triggering cancer development and treatment resistance
Mutations in the EGFR receptor can lead to uncontrolled cell growth and tumor formation. Osimertinib targets both the EGFR mutation that triggers cancer development and T790M, a mutation that makes tumors resistant to existing treatment with EGFR-TKIs.
Nearly two out of three patients with NSCLC whose disease progresses after treatment with an EGFR inhibitor develop the T790M mutation, for which treatment options are limited. A small number of patients (approximately 3-5%) have the T790M mutation at NSCLC diagnosis.
Combined results of three clinical trials
The EU approval for osimertinib is based on data from two Phase 2 studies (AURA extension and AURA2) and the AURA Phase 1 expansion study, which demonstrated efficacy in 474 patients with EGFRm T790M NSCLC who had progressed on or after an EGFR-TKI. After analyzing the results, scientists reported that:
- In the combined Phase 2 studies, the objective response rate (a measurement of tumor shrinkage) was 66%, and in the Phase 1 study it was 62%.
- Progression-free survival was 9.7 months in the combined Phase 2 studies and 11 months in the Phase 1 trial.
- Median duration of response in the Phase 1 study was 9.7 months.
- In the combined Phase 2 studies, median duration of response was not reached.
The most common adverse events based on data from the two AURA Phase 2 studies were generally mild to moderate and included diarrhea (42% all grades; 1.0% Grade 3/4), rash (41% all grades; 0.5% Grade 3/4), dry skin (31% all grades; 0% Grade 3/4) and nail toxicity (25% all grades; 0% Grade 3/4).
Warnings and precautions include interstitial lung disease and QT interval prolongation.
“Osimertinib offers greater prospects for durable treatment outcomes”
Eligibility for treatment with osimertinib will be dependent on mutation status, to be determined through a validated diagnostic test based on a tumor tissue sample or plasma. Availability of a blood-based test for circulating tumor DNA (ctDNA) means that physicians and patients have multiple options to test for a T790M mutation
Dr Matthew Peters, Chair of the Global Lung Cancer Coalition, added: “It is an exciting time in the care of patients with lung cancer. The ability to precisely characterize patients who have different types of lung cancer based on genetic mutations, and predict their response to targeted treatments, offers a more accurate and efficient approach to lung cancer care. Patients with common sensitizing EGFR mutations and the separate T790M have disappointing responses to standard treatments. “
He added “testing for the T790M status of lung cancer patients, using either a tumor sample or a simple blood test, and directing patients towards a medication such as osimertinib that is specifically designed for their pattern of mutations, offers greater prospects for durable treatment outcomes.”Source: eCancer News