Table 1.
Input parameters of the model.
| Parameters | Expected value | Range | Distribution | References |
|---|---|---|---|---|
| Clinical inputs | ||||
| ITT TNBC patients | ||||
| PFS: Atezolizumab + nab-paclitaxel | meanlog: 1.996 sdlog: 0.938 |
NA | Lognormal | (14) |
| OS: Atezolizumab + nab- paclitaxel | shape: 1.6892 scale: 22.1345 |
NA | Log-logistic | (14) |
| PFS: nab-paclitaxel | meanlog: 1.7856 sdlog: 0.941 |
NA | Lognormal | (14) |
| OS: nab-paclitaxel | shape: 1.3805 scale: 26.3036 |
NA | Weibull | (14) |
| TNBC patients with PD-L1-positive status | ||||
| PFS: Atezolizumab + nab-paclitaxel | meanlog: 2.0798 sdlog: 1.0586 |
NA | Lognormal | (14) |
| OS: Atezolizumab + nab- paclitaxel | meanlog: 3.2527 sdlog: 1.1196 |
NA | Lognormal | (14) |
| PFS: nab-paclitaxel | meanlog: 1.6705 sdlog: 0.975 |
NA | Lognormal | (14) |
| OS: nab-paclitaxel | shape: 1.301 scale: 25.56 |
NA | Weibull | (14) |
| TNBC patients with PD-L1-negative status | ||||
| PFS: Atezolizumab + nab-paclitaxel | shape: 1.934 scale: 6.657 |
NA | Log-logistic | (14) |
| OS: Atezolizumab + nab- paclitaxel | shape: 1.815 scale: 20.045 |
NA | Log-logistic | (14) |
| PFS: nab-paclitaxel | shape: 1.8035 scale: 6.2604 |
NA | Log-logistic | (14) |
| OS: nab-paclitaxel | shape: 1.456 scale: 26.4987 |
NA | Weibull | (14) |
| Cost estimates | ||||
| Atezolizumab (per 1,200 mg) | $4,756 | 3,567–5,945 | Gamma | (18) |
| Nab-paclitaxel (per 100 mg) | $105.67 | 79.25–132.09 | Gamma | (18) |
| Drug administration (per cycle) | $75.40 | 56.55–94.25 | Gamma | (20) |
| Best supportive care (per cycle) | $1,886.67 | 1,415–2,358.34 | Gamma | (19) |
| Terminal care (per patient) | $1,923.29 | 1,442.47–2,404.11 | Gamma | (20) |
| Costs of main adverse events | ||||
| Fatigue | $131.78 | 98.84–164.73 | Gamma | (22) |
| Anemia | $607.06 | 455.30–758.83 | Gamma | (22) |
| Neutropenia | $526.90 | 395.18–658.63 | Gamma | (22) |
| Neutrophil count decreased | $104.95 | 78.71–131.19 | Gamma | (21) |
| Utility estimates | ||||
| Progression free survival | 0.843 | 0.632–1 | Beta | (23) |
| Progressed disease | 0.60 | 0.45–0.75 | Beta | (23) |
| Disutility estimates | ||||
| Utility reduction due to fatigue | −0.029 | −0.022 to −0.036 | Beta | (24) |
| Utility reduction due to anemia | −0.029 | −0.022 to −0.036 | Beta | (24) |
| Utility reduction due to neutropenia | −0.012 | −0.050 to −0.083 | Beta | (24) |
| Probability of main grade 3-5 adverse events in atezolizumab plus nab-paclitaxel arm | ||||
| Fatigue | 3.8% | 2.9–4.8% | Beta | (14) |
| Anemia | 3.1% | 2.3–3.9% | Beta | (14) |
| Neutropenia | 8.4% | 6.3–10.5% | Beta | (14) |
| Neutrophil count decreased | 4.9% | 3.7–6.1% | Beta | (14) |
| Probability of main grade 3-5 adverse events in nab-paclitaxel arm | ||||
| Fatigue | 3.4% | 2.6–4.3% | Beta | (14) |
| Anemia | 3% | 2.3–3.8% | Beta | (14) |
| Neutropenia | 8.2% | 6.2–10.3% | Beta | (14) |
| Neutrophil count decreased | 3.7% | 2.8–4.6% | Beta | (14) |
| Other parameters | ||||
| Body surface area | 1.72 | 1.52–1.92 | Normal | (17) |
All costs sourced from China in this study were converted into US dollars ($1 = RMB 6.8974 in 2020).
BSC, best supportive care; ITT, intention-to-treat; PD-L1, programmed death ligand-1; TNBC, triple-negative breast cancer; PFS, Progression-free survival; OS, Overall survival.