What Patients with Extensive-Stage Small Cell Lung Cancer Should Know About the FDA's Approval of Imfinzi

The Food and Drug Administration’s approval of the immunotherapy Imfinzi (durvalumab) in combination with the chemotherapies etoposide plus either carboplatin or cisplatin for adults with extensive-stage small cell lung cancer offers yet another option in treating this patient population, according to Dr. Jorge Gomez.

“This is another useful drug that comes into our arsenal for small cell lung cancer, so it's always exciting when we get new drugs,” Gomez, medical director of the thoracic oncology program at Mount Sinai Hospital in New York City, said in an interview with CURE®. “Small cell lung cancer has been a cancer where for many years we have not been able to find new drugs. (Immunotherapy drugs known as checkpoint inhibitors are) really the first group of drugs to improve survival in 25 to 30 years.”

Although the emergence of a new approved therapy is exciting, Gomez noted that there is another immunotherapy — Tecentriq (atezolizumab) — already approved in the same setting that has a similar effect.

The new approval is “exciting because it confirms the previous trial with the other immunotherapy drug, so it shows that the benefit of these drugs is fairly similar, (but) it doesn’t really matter which drug you use,” he said. “There is another trial with a third drug called pembrolizumab (Keytruda) in the exact same setting which hopefully in the near future will give us results, but all it does is add another choice to the treatment, and there’s no way to choose between the two currently approved choices of Tecentriq and Imfinzi.”

The approval was based on results of the phase 3 CASPIAN trial, which demonstrated that patients who received Imfinzi plus standard-of-care chemotherapy had a 27% lower risk of death and a median overall survival of 13 months versus 10.3 months for patients who received standard-of-care chemotherapies alone.

Although Gomez described the two approved immunotherapies as interchangeable, he acknowledged the possibility that practice-changing findings could still arise from the CASPIAN trial. The trial was designed with three arms — one testing chemotherapy, a second considering Imfinzi and a third investigating Imfinzi plus tremelimumab, a checkpoint inhibitor that attacks cancer in a different way than Imfinzi — and results from the third arm have not yet been reported.

“That arm hasn’t given results yet. It will in the near future, and the hope is that that arm will be better,” he said. “We don't know if that will be the case, but if that is the case, then that definitely would become the new standard treatment.”

Read CURE®’s original coverage of the FDA’s approval of Imfinzi in extensive-stage small cell lung cancer.