The US Food and Drug Authority (FDA) has granted breakthrough therapy designation (BTD) for Enhertu (trastuzumab deruxtecan), jointly developed by AstraZeneca and Daiichi Sankyo, to treat a type of non-small cell lung cancer (NSCLC).

The FDA designation indicated Enhertu for the treatment of metastatic in patients whose tumours have a HER2 mutation and with disease progression after platinum-based therapy.

HER2 is a tyrosine kinase receptor growth-promoting protein expressed on the surface of tumours, and the overexpression of HER2 is associated with a specific HER2 gene alteration known as amplification and is often associated with aggressive disease and poorer prognosis.

AstraZeneca R&D Oncology executive vice president José Baselga said: “Today’s news is very welcome as we continue to evaluate the potential of Enhertu to help patients with this devastating type of lung cancer.

“Targeted treatments and immunotherapies are demonstrating tremendous advancements, but there remains an unmet medical need for patients with HER2 mutations who are not benefiting from such therapies or for those whose cancer continues to progress.”

Enhertu is a HER2-directed antibody-drug conjugate that treats HER2 mutant NSCLC

The US regulatory agency has granted the BTD based on data from the ongoing Phase 2 DESTINY-Lung01 clinical trial, which is currently evaluating Enhertu in patients with HER2-mutant (HER2m) metastatic NSCLC, and data from the Phase 1 clinical trial published in Cancer Discovery.

Enhertu is a HER2-directed antibody-drug conjugate (ADC), which is part of the Daiichi Sankyo’s oncology portfolio and the AstraZeneca’s advanced ADC scientific platform.

ADCs are targeted cancer medicines designed to deliver cytotoxic chemotherapy to cancer cells through a linker attached to a monoclonal antibody that binds to a specific target expressed on cancer cells.

In the DESTINY-Lung01 clinical trial, the overall safety and tolerability profile of Enhertu is consistent with that observed in Phase 1 clinical trial.

The gastrointestinal and haematological events including nausea, alopecia, anaemia, decreased appetite and decreased neutrophil count are the most common adverse events in the study.

Daiichi Sankyo oncology R&D, oncology development global head, senior vice president Gilles Gallant said: “We are encouraged by the promising evidence of activity seen with Enhertu in patients with advanced lung cancer and a HER2 mutation.

“We look forward to working closely with the FDA on the potential for Enhertu to become the first HER2-directed therapy approved for non-small cell lung cancer.”