DESTINY-Gastric02 phase 2 trial results : Enhertu shows clinically meaningful and durable tumor response

AstraZeneca said that Enhertu (trastuzumab deruxtecan) has shown clinically meaningful and durable response in the DESTINY-Gastric02 phase 2 trial featuring patients having HER2-positive advanced gastric cancer.

Enhertu is a HER2-directed antibody drug conjugate (ADC) developed by AstraZeneca and Daiichi Sankyo.

According to AstraZeneca, the antibody drug conjugate delivered the desired tumor response in patients suffering from HER2-positive metastatic and/or unresectable gastric or gastroesophageal junction (GEJ) adenocarcinoma, who were treated previously with a trastuzumab-containing regimen.

Commenting on the DESTINY-Gastric02 phase 2 trial results, Gilles Gallant — Senior Vice President, Global Head, Oncology Development, Daiichi Sankyo said: “The encouraging results from DESTINY-Gastric02 are consistent with those previously seen in the pivotal DESTINY-Gastric01 trial. This additional data will support our ongoing discussions with global health authorities as we work toward Enhertu becoming an option for patients with HER2-positive metastatic gastric cancer.”

Enhertu DESTINY-Gastric02 phase 2 trial results – AstraZeneca says Enhertu showed clinically meaningful and durable tumor response. Photo courtesy of AstraZeneca.

In the primary analysis of the mid-stage study, which is the first clinical trial of Enhertu particularly in Western patients having HER2-positive metastatic gastric cancer or GEJ adenocarcinoma, the antibody drug conjugate at 6.4 mg/kg dosage provided a confirmed overall response rate (ORR) of 38% as evaluated by independent central review (ICR).

AstraZeneca said that three (3.8%) complete responses (CR) and 27 (34.2%) partial responses (PR) were shown in patients subject to treatment with Enhertu.

Following a 5.7 month-median follow-up, the median duration of response (DoR) of the antibody drug conjugate was 8.1 months. On the other hand, the median progression-free survival (PFS) with Enhertu treatment was 5.5 months.

AstraZeneca added that the exploratory endpoint of confirmed disease control rate (DCR) of 81% was seen in the DESTINY-Gastric02 phase 2 trial.

Susan Galbraith — AstraZeneca Executive Vice President, Oncology R&D, commenting on the DESTINY-Gastric02 phase 2 trial results, said: “The data from DESTINY-Gastric02 reaffirm the clinical significance of the potential benefit of Enhertu in patients with advanced gastric cancer. Patients often experience disease progression following initial therapies, and then face limited treatment options, so today’s news brings hope to both patients and treating physicians.”

Enhertu has approvals in Israel, the US, and Japan for the treatment of adults having locally advanced or metastatic HER2-positive gastric or gastroesophageal junction adenocarcinoma who have been subjected to a prior trastuzumab-based regimen. The approvals were given on the basis of the findings of the DESTINY-Gastric01 trial.