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. 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.
The PACIFIC trial is a randomised, double-blinded, placebo-controlled multi-centre trial of Imfinzi as sequential treatment in unselected patients with locally-advanced, unresectable (Stage III) NSCLC who have not progressed following platinum-based chemotherapy concurrent with radiation therapy.
The trial is being conducted in 235 centres across 26 countries, including the US, Canada, Europe, South and Central America, Japan, Korea, Taiwan, South Africa and Australia. The primary endpoints of the trial are PFS and OS, and secondary endpoints include landmark PFS and OS, objective response rate and duration of response.
Imfinzi (durvalumab, previously known as MEDI4736), a human monoclonal antibody directed against PD-L1, blocks PD-L1 interaction with PD-1 and CD80 on T cells, countering the tumour's immune-evading tactics and inducing an immune response.
Imfinzi continues to advance in multiple monotherapy trials and combination trials with tremelimumab and other potential new medicines in IO. Imfinzi is being assessed in Phase III trials as a monotherapy in various stages of NSCLC, in small-cell lung cancer (SCLC), in urothelial bladder cancer and in head and neck squamous cell carcinoma (HNSCC). The combination of Imfinzi and tremelimumab is being assessed in Phase III trials in urothelial bladder cancer, NSCLC, SCLC and HNSCC and in Phase I/II trials in gastric cancer, pancreatic cancer, hepatocellular carcinoma and haematological malignancies.
About AstraZeneca in NSCLC
Lung cancer is the leading cause of cancer death among both men and women, accounting for about one-third of all cancer deaths and more than breast, prostate and colorectal cancers combined.
AstraZeneca has a comprehensive portfolio of approved and potential new medicines in late-stage clinical development for the treatment of NSCLC across all stages of disease and lines of therapy. We aim to address unmet needs of patients with EGFR-mutated tumours as a genetic driver of disease, which occur in 15-20% of NSCLC patients globally and 30-40% of NSCLC patients in Asia, with our approved medicines Iressa and Tagrisso and on-going FLAURA and ADAURA trials. Our extensive late-stage immuno-oncology programme focuses on 75-80% of patients with NSCLC without a known genetic mutation. Our portfolio includes Imfinzi (durvalumab), an anti-PDL1 antibody, which is in development as monotherapy (ADJUVANT, PACIFIC, MYSTIC, PEARL and ARCTIC trials) and in combination with tremelimumab, anti-CTLA-4 (MYSTIC, NEPTUNE and POSEIDON trials).
AstraZeneca's Approach to Immuno-Oncology (IO)
Immuno-Oncology (IO) is a therapeutic approach designed to stimulate the body's immune system to attack tumours. At AstraZeneca, and MedImmune, our biologics research and development arm, our IO portfolio is anchored by immunotherapies that have been designed to overcome anti-tumour immune suppression. We believe that IO-based therapies will offer the potential for life-changing cancer treatments for the vast majority of patients.
We are pursuing a comprehensive clinical trial programme that includes Imfinzi (anti-PDL1) monotherapy and in combination with tremelimumab (anti-CTLA-4) in multiple tumour types, stages of disease, and lines of therapy, and where relevant using the PD-L1 biomarker as a decision-making tool to define the best potential treatment path for a patient. In addition, the ability to combine our IO portfolio with small targeted molecules from across our oncology pipeline, and with those of our research partners, may provide new treatment options across a broad range of tumours.
About AstraZeneca in Oncology
AstraZeneca has a deep-rooted heritage in Oncology and offers a quickly growing portfolio of new medicines that has the potential to transform patients' lives and the Company's future. With at least six new medicines to be launched between 2014 and 2020 and a broad pipeline of small molecules and biologics in development, we are committed to advance New Oncology as one of AstraZeneca's five Growth Platforms focused on lung, ovarian, breast and blood cancers. In addition to our core capabilities, we actively pursue innovative partnerships and investments that accelerate the delivery of our strategy, as illustrated by our investment in Acerta Pharma in haematology.
By harnessing the power of four scientific platforms - Immuno-Oncology, the genetic drivers of cancer and resistance, DNA Damage Response and Antibody Drug Conjugates - and by championing the development of personalised combinations, AstraZeneca has the vision to redefine cancer treatment and one day eliminate cancer as a cause of death.
AstraZeneca is a global, science-led biopharmaceutical company that focuses on the discovery, development and commercialisation of prescription medicines, primarily for the treatment of diseases in three main therapy areas - Oncology, Cardiovascular & Metabolic Diseases and Respiratory. The Company also is selectively active in the areas of Autoimmunity, Neuroscience and Infection. AstraZeneca operates in over 100 countries and its innovative medicines are used by millions of patients worldwide.
1. Kantar, other market research based on 2016 patient numbers; Globocan 2012. G7 countries include the US, Japan, Germany, the UK, France, Italy and Canada.