Daiichi Sankyo has entered into a clinical trial collaboration agreement with a subsidiary of MSD to evaluate a potential new combination therapy for breast or lung cancers.

The combination consists of Daiichi Sankyo's investigational HER2 targeting antibody drug conjugate DS-8201 and MSD’s immunotherapy Keytruda.

Under the agreement, Daiichi Sankyo will carry out a two-part Phase Ib multicenter, open-label study to determine the safety, tolerability and dose of the combination and its efficacy in patients with HER2 expressing advanced/metastatic breast cancer and patients with HER2 expressing or HER2 mutant advanced/metastatic non small cell lung cancer (NSCLC).

The primary endpoints of the study are maximum tolerated dose/recommended expansion dose and overall response rate. Secondary endpoints include duration of response, disease control rate, progression-free survival, overall survival, time to response and safety, the firms said.

"We are excited to pursue this opportunity to evaluate the safety, tolerability and activity of DS-8201 in combination with Keytruda and whether this combination may provide a potential new treatment approach for patients with HER2 expressing advanced breast and non-small cell lung cancer," said Tom Held, vice president, head, Antibody Drug Conjugate Task Force, Oncology Research and Development, Daiichi Sankyo.

"Strategic collaborations like this support our goal to pursue, investigate and maximize the application of DS-8201 in combination with other compounds that target different pathways to address unmet needs of patients with cancer."

Further details of the agreement were not disclosed.