PCN193 Assessing the Impact of Modeling Non-Disease-Related Mortality on Long-Term Survivorship Rates in Previously Untreated Advanced Melanoma: A Case Study from CheckMate 067

Mixture cure models (MCM) provide a useful framework to explore survival heterogeneity and to estimate the proportion of long-term survivors (LTS) in a trial. We examined the sensitivity of LTS rates and resulting survival projections to modeling background mortality in an MCM for previously untreated advanced melanoma patients in the CheckMate 067 trial. For each arm, MCMs were fitted to 5-year progression-free survival (PFS) and overall...