Background Equitable access to essential medicines is a key facet of childhood cancer care, recognised by WHO as vital to improved childhood cancer outcomes globally. In the Caribbean, childhood cancer outcomes are poorer than those in most high-income countries. We aimed to generate in-depth comparative evidence of the current challenges and opportunities related to access to childhood cancer medicines in the Caribbean to identify contextsensitive health systems strategies to improve drug access and inform evidence-based paediatric cancer policies in the region.Methods In this convergent, parallel, mixed-methods study, we mapped and analysed the determinants of access to childhood cancer medicines in four Caribbean countries (The Bahamas, Barbados, Jamaica, and Trinidad and Tobago). We analysed contextual determinants of access to medicines within and across study site jurisdictions, alignment of childhood cancer medicine inclusion between each country's national essential medicines list (NEML) and WHO's 2017 Essential Medicines List for Children, and availability and cost of chemotherapeutic agents at five tertiary care hospitals. We used a mixed-effects logistic regression model to analyse the association of medicine price, procurement efficiency (via median price ratio [MPR]), and site with drug availability. The fixed effect evaluated the effect of site and MPR on the probability of stockout in a given month. We assessed determinants of medicine access via thematic analysis of semi-structured qualitative interviews, literature, and policy documents.Findings We collected and analysed data for 28 childhood cancer medicines from Barbados, 32 from The Bahamas, 30 from Trinidad and Tobago, and 31 from Jamaica. Despite stepwise inclusion of childhood cancer medicines in NEMLs, all four countries had frequent and recurrent stockouts for many cytotoxic medicines, showing no consistent relationship between NEML inclusion and availability. A mean MPR of greater than 3•0 in Trinidad and Tobago, The Bahamas, and Barbados suggests uniformly high procurement inefficiency, resulting in significant effects on drug stockout days. For each one unit increase in MPR the adjusted odds ratio (OR) of stockout increased by 10% (adjusted OR 1•10, 95% CI 1•04-1•16; p<0•01). These challenges in access to childhood cancer medicines stem from health system and policy dynamics at institutional, national, and supranational levels that cause price volatility and erratic medicine availability. Key challenges include disparate policy commitments (eg, among sites), inefficient procurement and supply chain management practices, and local effects of international market pressures. Interpretation The Caribbean region exemplifies deficiencies in access to childhood cancer medicines that might be overcome by improved regional harmonisation of drug registration, pharmacovigilance, and procurement alongside national forecasting to strengthen global pharmaceutical planning and prioritisation. Focused political attention to address these challenges is...
