Cost Utility and Budget Impact Analysis of 5-fluorouracil and Capecitabine Based Regimens for Management of Colorectal Cancer at Kenyatta National Hospital

Abstract

Background Colorectal cancer (CRC) is the third most common cancer globally and it is the fourth leading cause of cancer-related mortality. Management of CRC has progressively improved over the years, with a number of treatment options available. The cost of managing CRC poses a financial burden to the patients and the society due to the high costs involved. Cost effectiveness studies for capecitabine based and 5-fluorouracil based regimens have been conducted in other parts of the world, however applicability of this data in Africa is limited given the variation in economic status, treatment patterns and advances in technology. In Kenya, Kenyatta National Hospital as the largest national referral hospital and serves a high number of cancer patients with a challenge of limited bed capacity. In addition, the National Hospital Insurance Fund covers only part of the oncology care for cancer patients. Therefore, it is important to establish the most cost-effective regimen for the management of CRC. Objectives The main objective of the study was to compare the cost effectiveness of 5-fluorouracil and capecitabine based regimens for management of colorectal cancer in Kenyatta National Hospital. In addition, a budget impact analysis of the adoption of capecitabine based regimen was conducted. Methods A mixed study design was used. The study was divided into four parts. The first part was a descriptive cross sectional study that was conducted in the oncology wards at Kenyatta National Hospital to establish the cost of managing colorectal cancer and its complications. For this study, the study population was patients diagnosed with colorectal cancer and admitted in Kenyatta National hospital between January 2014 and December 2019. The second part of the study was a key informant interview that was carried out amongst the administrative officers in charge of billing and procurement to collect information on cost of procuring drugs and other resources used for management of colorectal and its complications. xi The third part of the study was a cost utility analysis which is one of the four designs accepted in Pharmacoeconomics. A markov decision model was developed using a theoretical cohort of colorectal cancer patients. Markov modelling was done to estimate long-term costs and benefits of 5-Fluorouracil compared to capecitabine based regimens for the management of colorectal cancer. The study was conducted from a provider perspective with a time horizon of 5 years. Effectiveness data was derived from literature. Lastly a budget impact analysis was conducted to assess the cost impact of the adoption of capecitabine based regimen on the budget at Kenyatta National Hospital. Descriptive and exploratory data analysis was performed using STATA version 13 software; for data obtained from retrospective review of patients’ files and chart review. The level of significance was set at 0.05. The quantitative data on costs was tabulated and summarized in MS Excel spreadsheet. The R version 3.6.0, ―heemod‖ package was used for costing, probabilistic and sensitivity analysis. Results The demographic and clinical characteristics of the participants showed that, majority of the participants were male (55.4%) and the elderly (>55years) (51.0%). Most participants were diagnosed with late stage disease (62.3%). Majority of the patients were on 5-FU regimens (67.2%). Neutropenia was the most common occurring side effect. Metastasis was the most common outcome (28.9%) while mortality was at 24.1%. The determinants for prescribing capecitabine regimen were presence of metastasis, patients who received radiotherapy and those who underwent any chemotherapy switch (p<0.001). FOLFOX was the most expensive regimen(Ksh. 577,270) compared to XELOX (Ksh.207,486). XELOX was found to be the most cost effective regimen with an incremental cost effectiveness ratio (ICER) of Ksh.-38632.74 per quality adjusted life years (QALY) gained. The ICER was negative for XELOX due to the lower cost and more QALY gained. The results show that the use of XELOX for managing colorectal cancer is cost saving each year. The impact of adopting XELOX on the KNH annual budget and medicines budget over 5 years ranged between 2.27% to 2.90%. xii Conclusion FOLFOX is the mainstay therapy for CRC management in KNH; it is however more expensive compared to XELOX. XELOX is the most cost effective regimen as compared to FOLFOX from the provider perspective and should be considered as a drug of choice in the management of colorectal cancer in Kenya.