IMpower133 and CASPIAN Trials for Extensive Stage SCLC

Mark Socinski, MD: I’m Dr Mark Socinski from the AdventHealth Cancer Institute in Orlando, Florida. Joining me today in this virtual discussion are my colleagues, Dr Roy Herbst, a medical oncologist from the Yale Cancer Center in New Haven, Connecticut; Dr Stephen Liu, a medical oncologist from the Georgetown Lombardi Comprehensive Cancer Center of Georgetown [University] in Washington, DC; and Dr Kristin Higgins, a radiation oncologist at the Winship Cancer Institute of Emory University in Atlanta, Georgia. Today we’re discussing a number of topics pertaining to the use of systemic therapy in patients with small cell lung cancer. We’ll discuss the latest research in the field and the impact of recent clinical trials on making decisions for treatment selection in this population. Dr Herbst will summarize recent trials because in the past year, we’ve seen a change in the standard of care based on 2 trials, IMpower133 and the CASPIAN trial. Could you bring us up to date and give us your impression of those trials?

Roy Herbst, MD, PhD: Yes. Immunotherapy has changed the way we think of cancer care, certainly lung cancer care, and it’s moved to small cell lung cancer. It makes sense. Small cell lung cancer is a smoking-related disease, there are large numbers of mutations, high TMB [tumor mutation burden], and it’s an obvious place to look for a new indication. The first drug to move forward was atezolizumab. At the World Conference on Lung Cancer 2 years ago in Toronto, the results were presented of IMpower133, which took atezolizumab plus platinum and etoposide in extensive stage small cell lung cancer. In my career, I haven't seen any changes in the standard of care treatment for small cell lung cancer until now. This randomized phase 3 study had a hazard ratio in the 0.7 range in favor of the atezolizumab, and that was approved and has become a new standard of care. Just right on the heels behind that is a second drug, durvalumab, another PD-L1 inhibitor, in combination with platinum/etoposide. The CASPIAN trial, which we learned about late last year, also was positive and updated at ASCO [the American Society of Clinical Oncology annual meeting] this year, again, with a hazard ratio between 0.7 and 0.8.

We have activity here; it’s a survival benefit. Its modest, but clearly, it’s at the level where we consider that clinically significant, and it’s something to build upon. For patients with small cell lung cancer, it’s great that we have these 2 drugs available in the frontline setting for this disease.

Transcript Edited for Clarity