4D Pharma plc (LON: DDDD) has entered a clinical collaboration agreement with a subsidiary of MSD, known as Merck (NYSE: MRK) in the US and Canada, the UK-based biopharmaceutical company announced on Thursday.

The agreement will see the two companies conduct a clinical trial to evaluate the combination of Keytruda (pembrolizumab) with 4D Pharma's live biotherapeutic candidate MRx0518 in patients with solid tumours.

Keytruda is an anti-PD-1 therapy marketed by MSD that enables the immune system to destroy specific cancer cells.

MRx0518 has shown therapeutic potential in a variety of tumour types in pre-clinical models and has the potential for synergy in combination with checkpoint inhibitor therapies.

The Phase I study will evaluate the safety, tolerability and preliminary clinical benefit of the combination of Keytruda with MRx0518 in patients who progressed on prior PD-1 inhibitor therapy with renal, bladder, melanoma and non-small cell lung cancer.