The lag between effectiveness and cost-effectiveness evidence of new drugs. Implications for decision-making in health care.

A new drug is approved for use if its efficacy and safety have been demonstrated. However, healthcare decision makers may also require data on the cost-effectiveness of new drugs if they are to make informed decisions about their place in therapy. Cost-effectiveness evidence may lag behind the effectiveness data in terms of its availability. We explored the timeliness of delivering cost-effectiveness information about new drugs with established effectiveness and significant financial impact. Drugs were identified, based on guidance documents and reports published by the UK National Institute for Clinical Excellence (NICE), and the following data were collected: dates of publication of first effectiveness and cost-effectiveness evidence, methodology of the cost-effectiveness analysis, quality scores of the clinical studies. Eighteen guidance documents on the use of new drugs/drug groups published by NICE by October 2001 covered 30 health technologies, which were included in the analysis. The analysis of the evidence showed that their effectiveness had been demonstrated in the last 12 years, with only two exceptions. However, cost-effectiveness evidence had been published for 21 (70%) of the technologies. The cost-effectiveness was estimated in 52.4% of cases using models. The good quality effectiveness evidence lagged behind the first effectiveness evidence by 1.40 years (95% CI 0.57-2.23), while the mean lag between the first effectiveness evidence and the first cost-effectiveness publications was estimated as 3.20 years (95% CI 1.76-4.65). Cost-effectiveness evidence thus often lags behind the effectiveness evidence. As a result healthcare decision makers are sometimes in a position of having to take decisions without having adequate cost-effectiveness data at their disposal.