The U.S. Food and Drug Administration (FDA) has granted accelerated approval for AstraZeneca’s Tagrisso (osimertinib), an oral prescription for the treatment of patients with advanced non-small cell lung cancer (NSCLC).
The drug is now approved to treat those patients whose tumors have a specific mutation in epidermal growth factor receptor (EGFR), the T790M mutation, and whose disease has worsened after treatment with other EGFR-blocking therapy.
Lung cancer is the leading cancer killer in both men and women in the U.S. Estimates of the National Cancer Institute indicate 221,200 new diagnoses and 158,040 deaths in 2015. NSCLC is the most common of lung cancers, and the EGFR gene is a protein involved in the development and spread of the cancer cells.
“Our understanding of the molecular basis of lung cancer and reasons these cancers become resistant to prior treatments is rapidly evolving,” said Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, in a press release. “This approval provides a new treatment for patients who test positive for the EGFR resistance mutation, T790M, and is based on substantial evidence from clinical trials that shows Tagrisso had a significant effect on reducing tumor size in over half of patients who were treated.”
The FDA has also granted approval to the first companion diagnostic test, called cobas EGFR Mutation Test v2. The cobas® EGFR Mutation Test v2 (US-IVD) identifies EGFR gene mutations in tumor tissue DNA from non-small cell lung cancer (NSCLC) patients and is intended to be used as an aid in identifying NSCLC patients for therapy with Tagrisso. The test utilizes tissue samples that have been formalin-fixed and paraffin embedded.
The recently approved v2 version adds the T790M mutation to the medically relevant mutations identified by the previous cobas EGFR Mutation Test v1.
“The approval of safe and effective companion diagnostic tests and drugs continue to be important developments in oncology,” said Alberto Gutierrez, PhD, Director of the Office of In Vitro Diagnostics and Radiological Health in the FDA’s Center for Devices and Radiological Health. “The availability of the cobas EGFR Mutation Test v2 meets a need for the detection of this important EGFR gene mutation, which can alter treatment effectiveness.”
Tagrisso’s efficacy and safety were determined in two multicenter, single-arm trials in 411 patients with a diagnosis of advanced EGFR T790M mutation-positive NSCLC and whose conditions were aggravated following an EGFR-blocking drug treatment.
A total of 57% of patients in the first trial and of 61% in the second trial treated with Tagrisso experienced partial or complete reduction in the size of their tumor (objective response rate). Continued FDA approval for this clinical indication may be dependent on further studies.
Tagrisso’s common side effects can include diarrhea, dry skin, rash and infection or redness around the fingernails, and possible serious side effects are lung inflammation and heart injury. The drug can be dangerous to a developing fetus.
The FDA previously granted AstraZeneca’s Tagrisso orphan drug designation, breakthrough therapy designation, and priority review.