Findings from the CASPIAN Phase 3 trial (NCT03043872) supported the decision. There, newly diagnosed patients with extensive-stage (widely spread) SCLC who received the combination lived significantly longer than those on chemo only. Response rates also were better with the Imfinzi combo.
Imfinzi, marketed by AstraZeneca, is the first immunotherapy of its kind to extend the survival of patients and improve response rates, when used in combination with a choice of chemotherapies. The therapy was approved for the same indication in the U.S. earlier this year.
“Imfinzi plus chemotherapy is becoming a new global standard of care for patients with extensive-stage small cell lung cancer, and we are pleased to bring this option to patients in Europe who urgently need it,” Dave Fredrickson, executive vice president of the oncology business unit at AstraZeneca, said in a press release.
SCLC is a type of lung cancer that is less common — and generally more aggressive (fast-growing) — than non-small cell lung cancer. “Extensive-stage,” in the context of SCLC, refers to cancer that has spread widely in the lungs or elsewhere in the body.
Imfinzi is an immune checkpoint inhibitor that works by blocking PD-L1, a protein that some cancer cells use to evade the immune system. Blocking PD-L1 allows the immune system to target and kill cancer cells more effectively.
In the European Union, Imfinzi also is approved to treat certain non-small cell lung cancers.
The ongoing AstraZeneca-sponsored CASPIAN trial is investigating the benefits of Imfinzi plus standard first-line chemotherapy to treat newly diagnosed extensive-stage SCLC patients. It enrolled 805 people at more than 200 centers in 23 countries.
Imfinzi-treated patients completed four cycles of chemotherapy, while controls received up to six such cycles plus optional prophylactic (preventive) cranial irradiation, a form of radiation therapy. Imfinzi was given at a dose of 1,500 mg every three weeks for four cycles during chemotherapy, then every four weeks until disease progression (worsening).
Results demonstrated that the addition of Imfinzi extended median overall survival from 10.3 to 13.0 months, which corresponds to a 27% lower risk of death. Similar benefits to survival were shown in a recent updated analysis, which had a median follow-up time of more than two years.
More participants given Imfinzi responded to treatment (68% vs. 58%).
The results revealed no new safety concerns related to the treatment; rates of severe adverse events (side effects) and treatment discontinuations were similar among participants on both groups.
“This is the first immunotherapy regimen to offer both a sustained survival benefit and an improved response rate, as well as a choice of chemotherapies and convenient dosing every four weeks during maintenance,” Fredrickson said.
“For the first time, patients with extensive-stage small cell lung cancer in Europe will have the option of an immunotherapy combination with cisplatin, a preferred chemotherapy for many European physicians in this setting,” said Luis Paz-Ares MD, PhD, oncologist at Spain’s Hospital Universitario Doce de Octubre, and an investigator for the CASPIAN trial.
“Today’s approval of Imfinzi provides physicians with an important new 1st-line treatment option that provides significant overall survival benefit with a well-tolerated treatment,” he said.
AstraZeneca is sponsoring another Phase 3 clinical trial, ADRIATIC (NCT03703297), which is evaluating Imfinzi after chemoradiation therapy in people with limited-stage SCLC — cancer that has not spread beyond one side of the chest, usually meaning it’s limited to a single lung (though sometimes lymph nodes are also involved).
The trial, expected to end in early 2024, is enrolling patients at locations around the world. More information about eligibility is available here.