Biopharmaceutical company AstraZeneca (STO:AZN) (LON:AZN) and Japan's Daiichi Sankyo Company Limited reported on Wednesday that Enhertu (trastuzumab deruxtecan) has been granted Priority Review in the United States for the treatment of HER2-positive metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma.

The US Food and Drug Administration (FDA) grants Priority Review to applications for medicines that offer significant advances over available options by demonstrating safety or efficacy improvements, preventing serious conditions, or enhancing patient compliance. The Prescription Drug User Fee Act date, the action date for the FDA's regulatory decision, will be during the first quarter of 2021.

The supplemental Biologics License Application (sBLA) was based on results from the DESTINY-Gastric01 randomised Phase II trial, which demonstrated a statistically significant and clinically meaningful improvement in objective response rate (ORR), the primary endpoint, and overall survival (OS), a key secondary endpoint, for patients treated with Enhertu versus chemotherapy (paclitaxel or irinotecan monotherapy).

According to AstraZeneca and Daiichi Sankyo, there are more than 27,000 new cases of gastric cancer in the US each year, of which approximately one in five are HER2 positive. For patients with metastatic gastric cancer who progress on initial treatment with an anti-HER2 medicine, there are no other approved HER2-directed medicines.