The US Food and Drug Administration (FDA) has approved Daiichi Sankyo and AstraZeneca’s Enhertu for adults with unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-positive [immunohistochemistry (IHC) 3+] solid tumours.

The indication has been cleared with accelerated approval.

This offers a HER2-directed antibody-drug conjugate (ADC) to patients who have exhausted other systemic treatments and lack satisfactory alternatives.

Discovered by Daiichi Sankyo, Enhertu is being co-developed in partnership with AstraZeneca.

The decision was based on the positive outcomes observed in the DESTINY-PanTumor02, DESTINY-Lung01 and DESTINY-CRC02 Phase II trials.

The approval hinges on the observed objective response rate (ORR) and duration of response (DOR) reported in these trials. Continued approval will depend on further verification and clinical benefit demonstrated in confirmatory trials.

In the DESTINY-PanTumor02 trial, subjects treated with Enhertu achieved a confirmed ORR of 51.4% and a median DoR of 19.4 months.

The DESTINY-Lung01 trial enrolled HER2-positive (IHC 3+) non-small cell lung cancer patients and reported a confirmed ORR of 52.9%. The DESTINY-CRC02 trial, which included patients with colorectal cancer, showed a confirmed ORR of 46.9% and a median DOR of 5.5 months.

AstraZeneca oncology executive vice-president Dave Fredrickson stated: “As the first ADC to be granted a tumour-agnostic indication, Enhertu is truly delivering on its potential across metastatic HER2-targetable tumours.

“This approval also elevates the importance of testing for biomarkers, including HER2, across a broad range of tumours to ensure these patients with advanced cancer who have few options know whether a targeted medicine might be right for them.”

This month, the FDA accepted AstraZeneca and Daiichi Sankyo‘s biologics licence application for datopotamab deruxtecan (Dato-DXd), a new treatment option for a subset of breast cancer patients.