AstraZeneca small cell lung cancer treatment Imfinzi gets nod in China

The approval by China's National Medical Products Administration was based on positive results from the CASPIAN Phase III trial. The trial showed that Imfinzi plus chemotherapy demonstrated a statistically significant and clinically meaningful improvement in overall survival (OS) versus chemotherapy alone. In addition, results from the China cohort of patients were consistent with the global results.

Small cell lung cancer (SCLC) is a highly aggressive, fast-growing form of lung cancer that typically recurs and progresses rapidly despite initial response to chemotherapy. Prognosis is particularly poor, as only 7% of all SCLC patients and 3% of those with extensive-stage disease will be alive five years after diagnosis.

Dave Fredrickson, Executive Vice President, Oncology Business Unit, said: "Today's approval of Imfinzi plus chemotherapy brings an important global standard of care to patients with extensive-stage small cell lung cancer in China, who have had few treatment options and a dire prognosis. Physicians can now offer these patients a well-tolerated immunotherapy regimen with sustained overall survival and prolonged treatment response, as well as convenient dosing. This is also the first time physicians have had the choice to combine immunotherapy with cisplatin, a preferred chemotherapy in this setting in China."

The CASPIAN Phase III trial met the primary endpoint of OS for Imfinzi plus chemotherapy in June 2019, reducing the risk of death by 27% versus chemotherapy alone (based on a hazard ratio [HR] of 0.73; 95% confidence interval [CI] 0.59-0.91; p=0.0047), with a median OS of 13.0 months versus 10.3 months for chemotherapy alone. These results were published in The Lancet in October 2019. Results also showed an increased confirmed objective response rate for Imfinzi plus chemotherapy (68% versus 58% for chemotherapy alone). Imfinzi added to chemotherapy delayed the time for disease symptoms to worsen.

An updated analysis showed sustained efficacy for Imfinzi plus chemotherapy after a median follow up of more than two years (OS HR of 0.75; 95% CI 0.62-0.91; nominal p=0.0032), with median OS of 12.9 months versus 10.5 months for chemotherapy alone. An estimated 22.2% of patients treated with Imfinzi plus chemotherapy were alive at 24 months versus 14.4% for chemotherapy alone. The safety and tolerability for Imfinzi and chemotherapy were consistent with the known safety profiles of these medicines. No patients tested positive for treatment-emergent anti-drug antibodies to Imfinzi.

Safety and efficacy results in the China cohort of patients were consistent with results in the overall global trial population. Detailed results from this cohort will be presented at a forthcoming medical meeting.

The CASPIAN Phase III trial used a fixed dose of Imfinzi (1500mg) administered every three weeks for four cycles while in combination with chemotherapy and then every four weeks as a monotherapy until disease progression. Based on the trial results, Imfinzi, in combination with etoposide and either carboplatin or cisplatin, is approved in the 1st-line setting of ES-SCLC in more than 55 countries, including the US, Japan and across the EU.

Imfinzi is also being tested following concurrent chemoradiation therapy in patients with limited-stage SCLC in the ADRIATIC Phase III trial as part of a broad development programme. In addition, Imfinzi is also approved to treat non-small cell lung cancer (NSCLC) in the curative-intent setting of unresectable, Stage III disease after chemoradiation therapy in the US, Japan, China, across the EU and in many other countries, based on results from the PACIFIC Phase III trial.