Number needed to treat (NNT) as a measure of drug benefit: Lenalidomide versus bortezomib for treatment of relapsed/refractory multiple myeloma (MM).

e18562 Background: Lenalidomide(LEN) and bortezomib(BORT) are active agents in the treatment of refractory MM. The former is administered 25 mg/day orally on days 1-21 of repeated 28-day cycles. The latter as a 1.3 mg/m^2 intravenous dose on days 1, 4, 8 and 11 for eight, three week cycles. Both agents have demonstrated an improvement in disease response, progression free (PFS) and overall survival (OS) in the refractory MM setting. NNT represents the number of patients that need to be treated with a new intervention in order to have one additional patient deriving benefit, and is a powerful approach that can be used to make sense of numerical results from clinical trials. In this analysis, the NNT approach was used to compare LEN and BORT in patients with relapsed MM. Methods: The pivotal randomized trials for LEN (Weber, Dimopoulos, 2007) and BORT (Richardson, 2005) were reviewed. A key requirement for a NNT comparative analysis is that all outcomes be measured against a comparable control. The NNT was ...