Apr 10, 2025

MISSISSAUGA, ON, April 10, 2025 /CNW/ - Health Canada has granted a Notice of Compliance (NOC) for IMFINZI® (durvalumab), as monotherapy, for the treatment of adult patients with limited-stage small cell lung cancer (LS-SCLC) whose disease has not progressed following platinum-based chemoradiation therapy (CRT), following a priority review of the submission.¹

The approval of Imfinzi was granted based on results from the pivotal ADRIATIC Phase III trial which demonstrated statistically significant and clinically meaningful results for its dual primary endpoints of overall survival (OS) and progression-free survival (PFS) for Imfinzi compared with placebo. The results of the ADRIATIC trial were presented during the Plenary Session of the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting and subsequently published in the New England Journal of Medicine.²

SCLC is a highly aggressive form of lung cancer.³ LS-SCLC typically recurs and progresses rapidly, despite initial response to standard-of-care chemotherapy and radiotherapy.^2,4 The prognosis for LS-SCLC is particularly poor, as only 15-30% of patients will be alive five years after diagnosis.⁵

"With this approval, we can now offer immunotherapy treatment to people living with limited-stage small cell lung cancer, which is almost always fatal, even in patients with limited disease burden," says Dr. Shantanu Banerji, Director of Precision Oncology and Advanced Therapeutics, CancerCare Manitoba. "The ADRIATIC trial demonstrated that Imfinzi can offer improved survival and greater odds of cure for these patients, the first major advance for this disease in close to 40 years."

In the ADRIATIC trial, Imfinzi reduced the risk of death by 27% versus placebo (based on an overall survival [OS] hazard ratio [HR] of 0.73; 95% confidence interval [CI] 0.57-0.93; P=0.0104). The estimated median OS was 55.9 months for the Imfinzi arm versus 33.4 months for the placebo arm. An estimated 57% of patients treated with Imfinzi were alive at three years compared to 48% for placebo.¹ 

Imfinzi also reduced the risk of disease progression or death by 24% (based on a progression-free survival [PFS] HR of 0.76; 95% CI 0.61-0.95; P=0.0161) versus placebo. Median PFS was 16.6 months for the Imfinzi arm versus 9.2 months for the placebo arm. An estimated 46% of patients treated with Imfinzi had not experienced disease progression at two years compared to 34% for placebo.¹ 

The safety profile for Imfinzi was generally manageable and consistent with the known profile of this medicine. No new safety signals were identified for Imfinzi in patients with LS-SCLC. The proportion of patients with adverse events leading to discontinuation of study treatment was 16.4% in the Imfinzi arm. The most common adverse events reported in the ADRIATIC study (any Grade; occurring in ≥10% of patients) for the Imfinzi arm were: pneumonitis or radiation pneumonitis, decreased appetite, hypothyroidism, cough, pruritus, nausea, dizziness, fatigue, diarrhea, pneumonia, rash, constipation and hyperthyroidism.¹

"This approval is great news for people living with this form of lung cancer and their families," says Shem Singh, Executive Director, Lung Cancer Canada. "The opportunity to live longer and with better outcomes is a significant advancement and a critical new treatment option for this aggressive disease, which has traditionally been known for its high rates of recurrence."

Small cell lung cancer
Lung cancer is the leading cause of cancer death among both men and women, accounting for about one-quarter of all cancer deaths.⁶ Lung cancer is broadly split into non-small cell lung cancer (NSCLC) and SCLC, with about 15% of cases classified as SCLC.⁷

LS-SCLC (Stage I-III) is classified as SCLC that is generally only in one lung or one side of the chest.⁸ LS-SCLC accounts for approximately 30% of SCLC diagnoses and the prognosis remains poor despite curative-intent treatment with standard-of-care concurrent chemoradiotherapy (cCRT).⁹

ADRIATIC² 
The ADRIATIC trial is a randomized, double-blind, placebo-controlled, multi-centre, global Phase III trial evaluating Imfinzi monotherapy and Imfinzi plus tremelimumab versus placebo in the treatment of 730 patients with LS-SCLC who had not progressed following cCRT. In the experimental arms, patients were randomized to receive a 1500 mg fixed dose of Imfinzi with or without tremelimumab 75 mg every four weeks for 4 cycles each, followed by Imfinzi every four weeks until disease progression, unacceptable toxicity, or for a maximum of 24 months.

The primary endpoints were PFS and OS for Imfinzi monotherapy versus placebo. Key secondary endpoints included OS and PFS for Imfinzi plus tremelimumab versus placebo, safety and quality of life measures. The trial was conducted at 164 centers in 19 countries across North and South America, Europe and Asia, including six clinical trial sites in Canada.

About Imfinzi (durvalumab)
Imfinzi is a fully human monoclonal antibody that binds to PD-L1 and blocks the interaction of PD-L1 with PD-1 and CD80, countering the tumour's immune-evading tactics and releasing the inhibition of immune responses.

About AstraZeneca
AstraZeneca is a global, science-led biopharmaceutical business whose innovative medicines are used by millions of patients worldwide. The company's core areas of scientific focus are Oncology; Cardiovascular, Renal and Metabolic (CVRM); Rare Disease; Respiratory & Immunology; and Vaccine & Immune Therapies. In Canada, the company employs more than 2,200 people and recently announced a major expansion of its research footprint in Mississauga – including the expansion of its AstraZeneca R&D Hub and the creation of a new Alexion Development Hub for Rare Diseases. AstraZeneca was recently recognized as one of Canada's Top 100 Employers, one of Canada's Most Admired Corporate Cultures, and a Greater Toronto Top Employer.

AstraZeneca is committed to contributing to a more sustainable future for people, society and planet taking important steps to help tackle some of the most pressing sustainability challenges globally – from climate and biodiversity loss, to health equity and health system resilience. AstraZeneca was one of the first seven companies globally to have its net zero targets verified by the Science-Based Targets initiative (SBTi) Corporate Net-Zero Standard. For more information, please visit the company's website at www.astrazeneca.ca.  

Imfinzi® is a registered trademark of AstraZeneca AB, used under license by AstraZeneca Canada Inc.

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