Projecting Expenditure on Medicines in the NHS

Abstract

Expenditure on medicines is a readily identifiable element of health service costs. As such, it is the focus of much attention by payers, not least in the UK despite the fact that the ex-manufacturer cost of medicines represents less than 10% of total UK National Health Service (NHS) expenditure. Projecting future spending on medicines enables the likely cost pressure to be allowed for in planning the scale and allocation of NHS resources. Simple extrapolations of past trends in medicines expenditure fail to account for changes in the rate and mix of new medicines becoming available and in the scope for windfall savings when some medicines lose their patent protection. This paper describes the methodology we have used to project medicines expenditure in the UK to 2015.Unlike any of the other forecasting approaches mentioned in the literature, we have adopted a product-by-product, pack-by-pack, expert-driven, bottom-up approach. Also, unlike other studies, our projections of the impact of loss of market exclusivity by existing medicines and the rate of uptake of newly launched medicines have been obtained from regression analysis of UK data, i.e. they are drawn directly from experience to date in the relevant market. For any projections, it is also important to address uncertainty by modelling a number of scenarios. In addition to a baseline scenario, we have created two other illustrative scenarios; many others also would be conceivable. We believe that our methodology provides a robust and comprehensive framework for projecting UK NHS medicines expenditure over the medium term.