An integrated restricted mean survival time-based evaluation of efficacy, toxicity, and cost in first-line immunotherapy regimens for metastatic renal cell carcinoma.

PURPOSES: To evaluate first-line metastatic renal cell carcinoma regimens using restricted mean survival time (RMST), which directly conveys absolute survival benefit, integrated with toxicity and cost.

MATERIALS AND

METHODS

Four pivotal phase 3 randomized trials comparing immune-based combinations were analyzed. Overall survival (OS) and progression-free survival (PFS) were reconstructed from published data, and absolute benefit from the control was expressed as the difference in RMST (dRMST). Drug cost, grade ≥3 adverse events (AEs; symptomatic and any), and high-dose corticosteroid (HDS) use were normalized per RMST month gained. Correlations between hazard ratio (HR) and dRMST were assessed. Principal component analysis (PCA) using incremental RMST, total incremental cost, and symptomatic grade ≥3 AEs was performed to explore multidimensional trade-offs.

RESULTS

OS dRMST gains were greatest with nivolumab-cabozantinib (4.15 months), followed by lenvatinib-pembrolizumab (3.53), nivolumab-ipilimumab (2.75), and pembrolizumab-axitinib (2.68). PFS gains were 10.07, 6.49, 4.39, and 1.44 months, respectively. dRMST strongly correlated with (1 - HR) for PFS (R² = 0.988, p = 0.006) and showed a positive trend for OS (R² = 0.890, p = 0.056). OS cost per month gained ranged from $52,207 (nivolumab-ipilimumab) to $293,168 (lenvatinib-pembrolizumab), whereas PFS cost per month gained was relatively consistent ($99,701-$111,721). Symptomatic grade ≥3 AEs per OS month gained were lowest with nivolumab-cabozantinib (<1%) and highest with lenvatinib-pembrolizumab (6%). PCA demonstrated distinct multidimensional positioning among regimens, with differing alignment of 3 factors between OS and PFS.

CONCLUSIONS

Integrated RMST-based analyses reveal clinically relevant trade-offs across regimens and distinct multidimensional profiles that may inform comparative treatment interpretation.