A phamacoeconomic analysis of personalized dosing versus fixed dosing of pembrolizumab in first-line PD-L1 positive non-small cell lung cancer.

9013 Background: In October 2016 pembrolizumab became the new standard of care for first-line treatment of patients with metastatic non-small cell lung cancer (mNSCLC) whose tumors express programmed death ligand 1 in at least 50% of cells. The FDA recommended dose is 200mg every three weeks. Multiple studies have demonstrated equivalent efficacy with weight-based doses between 2mg/kg to 10 mg/kg. The objective of this study was to compare the economic impact of using personalized dosing (2mg/kg) versus fixed dosing (200mg) in the first line setting of mNSCLC. Methods: We performed a budget impact analysis from the US societal perspective to compare fixed dosing with personalized dosing. We calculated the target population and weight of patients that would be treated with pembrolizumab annually in the first-line setting. Using survival curves from the KEYNOTE 024 trial with Weibull extrapolation we estimated the mean number of cycles that patients would receive. Using the Medicare average sales price we calculated the difference in cost between personalized and fixed dosing. Results: Our base case model demonstrates that the total annual cost of pembrolizumab with fixed dosing is US$ 3,440,127,429, and with personalized dosing it is US$ 2,614,496,846. The use of personalized dosing would lead to a 24% annual saving of US$ 825,630,583 in the United States. Conclusions: Personalized dosing of pembrolizumab may have the potential to save approximately 0.825 billion dollars annually in the United States, likely without impacting outcomes. This option should be considered for the first-line management of PD-L1 positive advanced lung cancer.