AstraZeneca announces positive results for the Phase III PACIFIC trial of Imfinzi

AstraZeneca and MedImmune, its global biologics research and development arm, today announced positive results for the Phase III PACIFIC trial, a randomised, double-blinded, placebo-controlled multi-centre trial of Imfinzi (durvalumab) as sequential treatment in patients with locally-advanced, unresectable (Stage III) non-small cell lung cancer (NSCLC) who had not progressed following standard platinum-based chemotherapy concurrent with radiation therapy.

A planned interim analysis conducted by an Independent Data Monitoring Committee (IDMC) concluded that the trial has already met a primary endpoint by showing statistically-significant and clinically-meaningful PFS, as assessed by blinded independent central review, in patients receiving Imfinzi compared to placebo. The results also demonstrate a favourable benefit/risk profile. The trial will also evaluate overall survival (OS), the other primary endpoint, which will be assessed in due course as specified by the protocol. AstraZeneca plans to submit the initial results from the PACIFIC trial for presentation at a forthcoming medical meeting.

Sean Bohen, Executive Vice President, Global Medicines Development and Chief Medical Officer at AstraZeneca, said: “These are highly encouraging results for patients with locally-advanced lung cancer for whom surgery is not an option. We look forward to working with regulatory authorities around the world to bring Imfinzi to lung cancer patients as soon as possible. Alongside this, we continue to explore Imfinzi’s full potential as monotherapy as well as in combination with tremelimumab and other medicines in areas of continued unmet need across multiple types of cancer.”

Stage III lung cancer represents approximately one third of NSCLC incidence and was estimated to affect around 100,000 patients in the G7 countries in 2016[i]. About half of these patients have tumours that are unresectable. The prognosis remains poor and long-term survival rates are low.

AstraZeneca recently received accelerated approval from the US FDA for Imfinzi in previously treated patients with advanced bladder cancer. Imfinzi is also being tested in the 1st-line treatment of patients with NSCLC as monotherapy in the MYSTIC and PEARL Phase III trials. It is also being developed in combination with tremelimumab, a checkpoint inhibitor that targets CTLA-4, as part of the MYSTIC, NEPTUNE and POSEIDON Phase III trials.