Ex ante budget impact analysis (BIA) of PD-1 inhibitor toripalimab plus gemcitabine-cisplatin (T+GC) versus a simulated pembrolizumab regimen in first line (1L) treatment of recurrent or metastatic nasopharyngeal cancer (rmNPC).

Abstract

e18024 Background: Interim results of the JUPITER-02 randomized double-blind phase 3 trial demonstrated a PFS benefit for T+GC (11.7 m) vs placebo+GC (8m) in 1L treatment of rmNPC. The KEYNOTE-028 nonrandomized (single group assignment) phase 1b trial showed the potential benefit of pembrolizumab in previously treated NPC. The trials were not comparable in population and design, precluding a direct comparison. We performed an ex ante BIA comparing T+GC to a simulated pembrolizumab+GC (sP+GC) regimen under an assumed equivalence in efficacy and safety. Methods: An ex ante budget impact model (budget holder perspective; accrual approach) compared a treatment mix “without” T+GC (only sP+GC) to one “with” T+GC in an annual incident US population of 1200 patients (year 1), a 5y time horizon, and a fixed 50/50 market share split. Population adjustments were for discontinuation, death, and progression with corresponding medication adjustments to estimate fully treated patient equivalents. Cost inputs included: drugs (average sales price), drug administration, and grade 3/4 adverse event (AE) management. Three scenarios were modeled: toripalimab priced at 70%, 80% and 90% of pembrolizumab. Results: In the “without” scenario, the 5y costs of sP+GC treatment totaled $2,062,509,042 and the 5y cost of managing AEs $210,382,926, for a total of $2,272,891,967. In the “with” scenario at 50% market share, the corresponding 5y costs for sP+GC declined to $1,031,254,521 for treatment and $105,191,463 in AE costs, for a total of $1,136,445,984. The corresponding costs for T+GC priced at 70%, 80%, 90% of pembrolizumab were $746,834,887, $841,641,432 and $936,447,976 (treatment) and $105,191,463 (AE management), for 5y gross budget impacts of $852,026,350, $946,832,895 and $1,041,639,439. Net savings “with” T+GC were $49,331,430, $32,887,620 and $16,443,810 in 2022 rising to $64,974,264, $43,316,176 and $21,658,088 by 2026. The total 5y net budget impact of adding T+GC to the treatment mix totaled $284,419,634, $189,613,089 and $94,806,545 in savings. Conclusions: Citing the findings from the JUPITER-02 trial of T+GC, regimens including a PD-1 inhibitor, gemcitabine and cisplatin are now a NCCN category 2A recommendation for 1L treatment of rmNPC. This ex ante BIA demonstrates the substantial savings potential of toripalimab (at a discounted cost compared to pembrolizumab) in rmNPC. With forthcoming final JUPITER-02 data showing a PFS benefit of 21.4m, the value of an available, lower-priced and efficacious anti-PD1 agent is highly significant to patients, providers and payers in terms of both clinical efficacy and cost efficiency. Emerging data suggest that toripalimab may be effective in more frequently occurring tumor types and the savings from such expanded access are likely to be multifold.