Cost-effectiveness analysis of toripalimab for metastatic or recurrent triple-negative breast cancer

Toliparibizumab in combination with nab-paclitaxel (T+N) has excellent efficacy inmetastatic or recurrent triple-negative breast cancer (TNBC), but the optimal choice of sequence of therapy is unclear given the trade-offs between quality of life and cost. Cost-effectiveness analyses can quantify these tradeoffs, leading to more informed decisions. Our objective was to assess the societal cost-effectiveness of the T+N regimen for metastatic or recurrent TNBC.

Clinical data were extracted from a multicenter, randomized, double-blind trial, TORCHLIGHT (NCT04085276). Patients were randomized into the T+N group or placebo plus nab-paclitaxel (P+N) group. 531 patients from 53 study locations were randomly assigned (T+N, n=353; P+N, n=178) into intend to treat (ITT) population; 200 and 100 patients, respectively had programmed death protein 1 (PD-L1) positive TNBC. A Markov model was established with a 21-day cycle length. Costs were acquired from local hospitals, effect parameters included quality-adjusted life year (QALY) and incremental cost-effectiveness ratio (ICER).

The cost differences were 47,538.3 CNY in ITT population (T+N, 143,725.67 CNY; P+N group, 96,187.37 CNY) and 29,258.84 CNY in PD-L1+ subgroup (T+N, 100,128.28 CNY; P+N group, 70,869.45 CNY). Meanwhile, the IEs were 0.03409 in the ITT population (T+N, 0.55323 QALY; P+N, 0.51914 QALY) and 0.03409 in the PD-L1+ subgroup (T+N, 0.42327 QALY; P+N, 0.37628 QALY). The ICERs between T+N and P+N groups were 1,394,548.41 CNY/QALY in the ITT population and 622,663.98 CNY/QALY in the PD-L1+ subgroup. We also analyzed the cost-effectiveness of toripalimab could be received in the Chinese medical insurance catalog. If toripalimab could be reimbursed at an 80% rate, the cost differences were changed to 16,598.99 CNY in ITT population (T+N, 112,786.36 CNY; P+N group, 96,187.37 CNY) and 7,704.58 CNY in PD-L1+ subgroup (T+N, 78,574.03 CNY; P+N group, 70,869.45 CNY). Meanwhile, the IEs remained unchanged. The ICERs between T+N and P+N groups were changed to 486,935.82 CNY/QALY in the ITT population and 163,962.96 CNY/QALY in the PD-L1+ subgroup. Sensitivity analyses indicated the stability of the model and the impact of utility.

At current drug prices, the T+N group is not more cost-effective than the P+N group, but after incorporating toripalimab into medical insurance, the T+N group will be more cost-effective for patients with PD-L1+ metastatic or recurrent triple-negative breast cancer.