Evaluation of a risk-sharing agreement for atezolizumab treatment in second- and third-line NSCLC patients: A strategy in order to improve access in low income countries.
Authors: Arrieta Oscar , Ramos-Ramirez Maritza , Garces-Flores Homero , Valencia-Velarde Angel , Cabrera-Miranda Luis A. , Frias-Gasga Abraham , Soto-Molina Hernan 
Published: June 2023

e18683 Background: A targeted treatment approach using anti-PDL1 agents can maximize clinical benefits. However, this type of treatment is expensive, resulting in barriers to treatment access. PD-L1 expression is a predictor of outcomes for patients treated with immune checkpoint inhibitors. There is extensive evidence about the clinical benefits maintained in patients who respond to immunotherapy treatment. The aim of this study is to evaluate the economic implications of implementing a risk-sharing agreement (RSA) for atezolizumab in non-small cell lung cancer patients (NSCLC). Methods: We developed a prospective cost analysis of a RSA for atezolizumab as a second-line (or above) therapy in patients with advanced NSCLC at the Instituto Nacional de Cancerología (INCan) in México. All patients had an ECOG PS 0-1 and PDL1≥1%. The first 4 cycles were funded by the pharmaceutical company. If patients had response by RECIST or clinical benefit (RP), a special government program in the institution absorbed the cost of treatment until progression. A budget impact estimation was performed based on direct medical costs considering a time horizon of 1 year. Secondary endpoints were estimated for each strategy, expressed as the total amount expended and the average cost per patient with or without risk-sharing agreement. Costs and results are express in USD. Results: In total 30 patients were included for second line (n = 23) and third line (n = 7) therapy. The median PFS in all population was 4.67 months (95% CI 3.4-7.8). After 4 cycles, 47% (n = 14) of patients had a RP and increased PFS up to 9.4 months (p < 0.001). A median OS in all cohort was 7.59 months (95% CI 5.1-17.2), however it was longer in patients with RP; 19 months (95% CI 8.81-NR) (p = 0.03). In addition, 33% of patients had RP and PDL1 ≥ 5% whose median OS was not reached The total cost of treatment was $611,557.64 (average $20,385.25 p/p) without a risk-sharing agreement, compared to an overall cost of $260,165.41 (average of $8,672.18 p/p) implementing a risk-sharing agreement. Regarding risk-sharing, non-parametric test as well as paired t test on transformed costs data showed a statistically significant difference in pharmacological cost between the two strategies in relation to cost per patient (p < 0.001). The implementation of a risk-sharing agreement reduced the therapy cost by US$351,392.24 which represents 1.41% of the annual INCan drug budget. Conclusions: Risk-sharing agreement makes it possible to select those patients who have more benefit, thus ensuring that government resources are invested in the population with longer survival, which translates into saving for the state. In this study, the economic impact of risk-shared accounts for a 57.46% reduction in total cost. This is clearly a resource-efficient and treatable option for more patients, particularly in low-income countries.