Science-led biopharmaceutical company AstraZeneca Plc (LON:AZN) on Wednesday announced final overall survival (OS) results from the phase III NEPTUNE trial, a randomised, open-label, multi-centre, global trial of Imfinzi (durvalumab) in combination with tremelimumab, an anti-CTLA4 antibody, versus standard-of-care (SoC) platinum-based chemotherapy in previously untreated stage IV (metastatic) non-small cell lung cancer (NSCLC) patients.

This trial was performed in an all-comers population and the primary analysis population was patients with a high tumour mutational burden (TMB). TMB is a measurement of the number of mutations within the genome (DNA) of a tumour and tumours with high levels of TMB may be more visible to the immune system.

According to the company, in the primary analysis population of patients whose blood TMB was 20 or more mutations per megabase (mut/Mb), the combination of Imfinzi and tremelimumab did not meet the primary endpoint of improving OS compared to SoC chemotherapy. The safety and tolerability profile for the combination of Imfinzi and tremelimumab was consistent with previous trials.

AstraZeneca added that it will submit the full results for presentation at a forthcoming medical meeting.

Imfinzi is also being tested as monotherapy in the phase III PEARL trial and in combination with chemotherapy with or without tremelimumab in the phase III POSEIDON trial as part of an extensive late-stage Immuno-Oncology programme in stage IV NSCLC.

Imfinzi is approved for unresectable, stage III NSCLC in 49 countries, including the US, Japan and across the EU, based on the phase III PACIFIC trial. Imfinzi is also approved for previously-treated patients with advanced bladder cancer in the US, Canada, Brazil, Australia, Israel, India, UAE, Qatar, Macau and Hong Kong.

AstraZeneca is focused on the discovery, development and commercialisation of prescription medicines, primarily for the treatment of diseases in the three therapy areas of Oncology, CVRM and Respiratory.