Corey J. Langer, MD, FACP of the University of Pennsylvania discusses his concerns over the PACIFIC Trial data such as the survival data not being released and how significant PFS may not be enough.
The overall survival data for the Pacific Trial was not released, which might make a big difference in the curative setting. Improving overall survival cure rate is still the standard arbiter practice changing approaches and PFS may not be enough. If additional year of therapy with durvalumab will be given, of course, with its potential toxicity, in order to get an additional year of progression-free survival, this is something to be discussed with the patient and the family.
In the United States, it is standard to obtain PET imaging as part of the simulation in assessing these patients. In performing PET to locally advanced patients, up to 20% of them maybe upstage. Since in the Pacific Trial PET was not routinely used, there is a possibility that there are CT-occult but PET detectable metastatic disease that had been treated with durvalumab versus the standard of care no treatment.
Another concern is on the nature of the radiation and the percentage of patients that actually got them. There is also no data on the nature of chemotherapy. Theres minor imbalance on the distribution of the PD-L1 scores of 25% or more is considered highest level for durvalumab, and in this trial around 24% of those in the durvalumab arm have levels that are high compared to only 17 or 18% in the controlled group. This may have inadvertently favored the durvalumab arm.
So, while this is a very promising approach and hopefully be the standard approach, but it is important to know and see the overall survival data.