Oct 13 Hip and spine bone mineral density
increased significantly among post-menopausal women on Merck &
Co's experimental new osteoporosis drug who had
previously taken a standard older company treatment, the
drugmaker said on Saturday.
The favorable results were seen in a mid-stage trial of
Merck's odanacatib, a once-weekly pill which works by blocking
an enzyme called cat-K found within bone cells. The enzyme plays
a key role in the body's natural process of dissolving bone
The study involved 243 women with osteoporosis who had
previously been treated for at least three years with
alendronate, the chemical name of Merck's Fosamax drug. It
belongs to an older class of medicines called bisphosphonates
whose sales have been hurt by rare reports of leg fractures and
deterioration of jaw bone in patients taking them.
"Odanacatib may be a viable alternative for patients who
need continued therapy and who want benefits beyond what they
received from bisphosphonates," senior Merck research executive
Albert Leung said in an interview, referring to favorable data
from the new trial.
Patients were given 50-milligram weekly doses of odanacatib,
or a placebo, for 24 months. All patients also received vitamin
D3 and calcium supplements, if needed.
At the end of the study, bone mineral density was shown to
increase by a statistically significant degree at three
pre-specified hip sites, including a 0.83 percent increase for
the total hip. That compared with a 1.87 percent decline in bone
mineral density for the total hip among patients receiving
Bone mineral density increased by 2.28 percent at the lumbar
spine among those taking odanacatib, compared with a 0.3 percent
decrease for patients on placebos. There was no difference
between the odanacatib and placebo groups in changes of bone
mineral density in the forearm.
The overall incidence of side effects were similar between
the two treatment groups.