Invited discussant Benjamin Besse, MD, of Gustave Roussy Cancer Center, Villejuif, France, was generally positive about the findings of Impower010 but said that longer-term follow-up of overall survival will be very important.

Benjamin Besse, MD

“IMpower010 is the first adjuvant study establishing an immune checkpoint inhibitor as a new standard of care in patients with resected non–small cell lung cancer. There is a disease-free survival benefit in patients with stage II to IIIA, but we need to cure more patients, not just delay relapse. Overall survival is still immature,” he said.

“The absence of a benefit for adjuvant atezolizumab in the PD-L1–negative population, which is roughly half of all patients, suggests that the optimal population for this treatment needs to be defined, as does the best perioperative strategy [ie, neoadjuvant or adjuvant]. My take on these data is that if atezolizumab is approved, I would prescribe adjuvant atezolizumab until I see the overall survival curves,” he stated.

Dr. Besse pointed out that atezolizumab is an accepted standard, yet only half of all patients in the study received it at relapse. Also, it is not clear from these data that rechallenge with atezolizumab (in 12% of patients) was successful.

More Information Needed

Dr. Besse took issue with the high percentages of patients who received radiotherapy and surgery subsequently. “Is this due to poor quality of surgery initially? What is the rate of curative intervention? We don’t have this information,” he told the audience. “I don’t want to delay relapse. I want to cure patients. I don’t want to guess if the overall survival will be positive,” he continued.

He would have liked more information about the incidence of brain metastases in the different disease stages. “Chemotherapy has no impact on brain metastasis. We need to follow this with immunotherapy,” he said.

Although he was generally positive about the study, he discussed the “dark side of immunotherapy,” including hyperprogression of micrometastatic disease, delayed side effects,the need to monitor immune-related side effects, and second cancers.

“There are small numbers, and it is too early to tell,” Dr. Besse commented. He said there will be two areas of debate regarding adjuvant immunotherapy. One concerns how to capture residual micrometastases and host factors such as antidrug antibodies, immune function, and the microbiota. The other will be about the importance of disease-free survival vs overall survival. “Who benefits the most? Clearly those with PD-L1 > 50%. Will adjuvant immunotherapy change the outcome if patients receive it at disease recurrence?” he asked.

Finally, there is a lot of controversy over which is better—adjuvant immunotherapy or neoadjuvant immunotherapy. There are pros and cons for each. The future will provide these answers. 

DISCLOSURE: Dr. Besse reported no conflicts of interest.