Extrapolation is often required to inform cost-effectiveness (CE) evaluations of immune-checkpoint inhibitors (ICIs) since survival data from pivotal clinical trials are seldom complete. The objectives of this study were to evaluate the accuracy of estimates of long-term overall survival (OS) predicted in French CE assessment reports of ICIs, and to identify models presenting the best fit to the observed long-term survival data.

A systematic review of French assessment reports of ICIs in the metastatic setting since inception until May 2020 was performed. A targeted literature review was conducted to collect associated extended follow-up of randomized controlled trials (RCTs) used in the CE assessment reports. Difference between projected and observed OS was calculated. A range of standard parametric and spline-based models were applied to the extended follow-up data from the RCT to determine the best-fitting survival models.

Of the 121 CE assessment reports published, 11 reports met the inclusion criteria. OS was underestimated in 73 percent of the CE assessment reports. The mean relative difference between each source was −13 percent (median: −15 percent; IQR: −0.4 to 26 percent). Models providing the best fit were those that could reflect nonmonotonic hazards.

Based on the available data at the time of submission, longer-term survival of ICIs was not fully captured by the extrapolation models used in CE assessments. Standard and flexible parametric models which can capture nonmonotonic hazard functions provided the best fit to the extended follow-up data. However, these models may still have performed poorly if fitted to survival data available at the time of submission to the French National Authority for Health.

In recent years, the use of both molecular targeting agents (MTAs) and immune-checkpoint inhibitors (ICIs) tend to occupy important positions in systemic anticancer therapy (SACT). The objective of this study is to describe the predictors of SACT include both MTAs and ICIs near the end of life (EOL) and the effect on EOL care in patients with advanced cancer.

We analyzed all patients who died of advanced cancer from August 2016 to August 2019, and we analyzed the survival time of patients who underwent anticancer agents excluded due to the loss of information about the last administration of SACT. The primary endpoint of this study was to identify predictors during the last administration of SACT near EOL.

In a multivariate analysis, the Eastern Cooperative Oncology Group performance status (ECOG-PS) (ORs 33.781) was significantly related factors within 14 days of death from the last administration of SACT. Age (ORs 0.412), ECOG-PS (ORs 11.533), primary cancer site of upper GI cancers (ORs 2.205), the number of comorbidities (ORs 0.207), MTAs (ORs 3.139), and ICIs (ORs 3.592) were significantly related factors within 30 days of death. The median survival time (MST) of patients with PS 3–4 was 29 days, while that of patients with both PS 0–2 was 76 days. The prevalence rate of delirium with MTAs was 17.5%, which was significantly lower than that of patients without it (31.8%). The prevalence rate of the mean dose of opioids in patients with ICIs was 97.9 mg/day, which was significantly higher than that of patients without it (44.9 mg/day).

Age, ECOG-PS, primary cancer site, the number of comorbidities, MTAs, and ICIs use were significant associated with SACT near EOL. Information on these factors may aid clinical decision making in referral to palliative care institutes.