Merck & Co claims superiority of Fosamax over Lilly's Evista in bone mass

US drug major Merck & Co has presented data from two large, head-to-head studies showing that its osteoporosis drug Fosamax (alendronate) 70mg once-weekly significantly increased (p=0.001) bone mass density at the lumbar spine and total hip compared to Eli Lilly's Evista (raloxifene) 60mg once-daily. Findings from the EFFECT (EFficacy of Fosamax versus Evista Comparison Trials), one concluded in the USA and one internationally, were presented at the 25th annual meeting of the American Society for Bone and Mineral Research.

Fosamax is currently the world's biggest-selling osteoporosis drug, with Merck projecting sales of $2.6-$2.8 billion for full-year 2003 in a multi-billion dollar market that could well be set to grow even larger due to recent concerns over hormone replacement therapy, also used to stem bone-density loss in menopausal women (Marketletter September 22).

In these two studies, postmenopausal women who took Fosamax experienced a two-fold increase in BMD at the lumbar spine and at the hip compared to Evista, 4.4% and 1.9% (lumbar) and 2.0% and 1.0% (hip), respectively, in the US trial; and 4.8% and 2.2%, and 4.8% vs 2.2% (lumbar) and 2.3% and 0.8% (hip) in the international study, after one year of treatment. Differences in efficacy at both spine and hip were seen as early as six months in both studies.