US regulators have issued a full approval for AstraZeneca’s lung cancer drug Tagrisso on the back of a strong progression-free survival (PFS) benefit observed in a late-stage trial.

The drug had already picked up an accelerated approval for the treatment of patients with metastatic epidermal growth factor receptor (EGFR) T790M mutation-positive non-small cell lung cancer (NSCLC) whose disease has progressed on or after an EGFR tyrosine kinase inhibitor (TKI) therapy.

Almost two-thirds of NSCLC patients who are EGFR mutation-positive and experience disease progression after being treated with an EGFR-TKI develop the T790M resistance mutation, for which there have been limited treatment options to date, AZ said, highlighting the drug’s potential scope.

Full clearance was issued after Tagrisso was shown to significantly improve PFS versus platinum-based doublet chemotherapy in the Phase III AURA3 trial, providing 10.1 months of median PFS compared to 4.4 months from chemotherapy.

Safety signals were also good, with the most common (>20 percent) adverse reactions observed in Tagrisso-treated patients diarrhoea (41 percent), rash (34 percent), dry skin (23 percent), nail toxicity (22 percent), and fatigue (22 percent), while serious side effects were reported in 18 percent of patients given the drug versus 26 percent of those in the chemotherapy group.

“The FDA’s full approval reinforces the potential of Tagrisso to become the standard of care for patients with metastatic EGFR T790M mutation-positive non-small cell lung cancer whose disease has progressed on or after first-generation EGFR-TKI therapy,” noted Sean Bohen, AstraZeneca’s chief medical officer.

Tagrisso is a third generation, irreversible EGFR tyrosine kinase inhibitor designed to inhibit both EGFR sensitising and EGFR T790M resistance mutations and to have activity in the central nervous system (CNS). The drug is also being assessed in the adjuvant and metastatic first-line settings, including in patients with and without CNS metastases, in leptomeningeal metastases, and in combination with other treatments.