Positive results from Merck's Phase IIB clinical study of odanacatib for treating osteoporosis

www.merck.comSep 15 2009

New data from a Phase IIB clinical study of odanacatib, Merck & Co., Inc.'s oral, once-weekly investigational treatment for osteoporosis, showed that when stopping treatment after two years, the increases in lower back (lumbar spine) bone mineral density (BMD) were reversed over the next year, while BMD at the hip (femoral neck) remained above levels observed at the start of the study. Additionally, three years of treatment with odanacatib 50 mg demonstrated increases in BMD at key fracture sites and minimal impact on the formation of new bone as measured by biochemical markers of bone turnover. These new data were presented at the 31st Annual Meeting of the American Society for Bone and Mineral Research (ASBMR).

“The 'rapid off' effect results showed that the drug's effect did not persist long after the drug cleared the body,” said Art Santora II, MD, PhD, Executive Director Clinical Research, Merck Research Labs. “Additionally, the continued increases in BMD seen at three years while sparing bone formation adds to the existing scientific evidence for the potential of odanacatib as a novel treatment option for osteoporosis."

Odanacatib is currently in Phase III clinical trials and is being evaluated in a large-scale, global outcomes study to determine its effects on vertebral, hip and non-vertebral fractures. Odanacatib is a cathepsin K inhibitor that selectively inhibits the cathepsin K enzyme. Cathepsin K is known to play a central role in the function of osteoclasts, which are cells that break down existing bone tissue, particularly the protein components of bone. Inhibition of cathepsin K is a novel approach to the treatment of osteoporosis.