Daiichi Sankyo and AstraZeneca said that the HER2 directed antibody drug conjugate (ADC) DS-8201 has met the primary endpoint in the phase 2 DESTINY-Gastric01 trial.
DS-8201 is trastuzumab deruxtecan in Japan and other regions of world barring the US where it is fam-trastuzumab deruxtecan-nxki.
The mid-stage trial for the ADC was held in 189 patients having HER2 positive unresectable or metastatic gastric or gastroesophageal junction cancer that had advanced after two or more treatment regimens including trastuzumab and chemotherapy.
The DESTINY-Gastric01 trial achieved a statistically significant and clinically meaningful improvement in objective response rate (ORR) for patients subjected to the ADC compared to investigator’s choice of chemotherapy, which was irinotecan or paclitaxel monotherapy. ORR is the primary endpoint of the mid-stage study.
The investigational drug also delivered a statistically significant and clinically meaningful improvement in overall survival (OS), which is one of the key secondary endpoints of the trial.
Furthermore, DS-8201’s safety profile in the DESTINY-Gastric01 trial was on par with what was observed in previous clinical trials.
Daiichi Sankyo said that the results of the DESTINY-Gastric01 study confirmed activity that was observed in the ADC’s non-randomized phase 1 study in patients having HER2 positive advanced gastric cancer.
AstraZeneca oncology R&D executive vice president José Baselga said: “Gastric cancer is usually diagnosed in the advanced stage and patients face markedly high mortality rates, making the need for new therapies especially urgent.
“Given the previous results seen in our HER2 positive development program and now in HER2 positive gastric cancer, we believe this antibody drug conjugate has the potential to redefine the treatment of patients with HER2 expressing cancers.”
The drug candidate is being jointly developed and commercialised in all parts of the world by Daiichi Sankyo and AstraZeneca with the exception of Japan where the former has retained exclusive rights.
The joint work on DS-8201 by the two companies is part of their $6.9bn cancer deal signed in March 2019.
Daiichi Sankyo plans to engage with the Japan Ministry of Health, Labour and Welfare (MHLW) regarding the next steps for the ADC’s regulatory submission based on the data of the DESTINY-Gastric01 trial.
Daiichi Sankyo senior vice president and oncology development, oncology R&D global head Gilles Gallant said: “Our development plan remains on track for gastric cancer, including an initial regulatory application in Japan where gastric cancer is highly prevalent and where SAKIGAKE designation has been granted for this indication. We are strongly committed to bringing this therapy as rapidly as possible to patients in need.”
Likewise in other countries, Daiichi Sankyo alongside AstraZeneca will look to discuss the trial results with other health authorities.