New Osteoporosis Drugs in the Works
Biologic Osteoporosis Drugs Denosumab and Odanacatib Show Promise in Clinical Trials
Denosumab's Clinical Trial continued...
Cancer risk is another thing
that researchers would check on, but tumors weren't more common with denosumab
than with alendronate, according to a news release from Amgen, the drug company
which makes denosumab.
It's also important that denosumab mainly affects the skeleton and not other
body systems, says Bukata, who hasn't seen any worrisome data for
"I and others fully expect denosumab up in front of the FDA soon,"
says Bukata, predicting that denosumab will get FDA approval. "Their data
has been good, there have been very solid studies, very open reporting all
along the way."
Bukata likes the fact that denosumab is given by injection twice a year, and
that those injections don't have to be given by a doctor. That should help with
compliance, notes Bukata.
Odanacatib takes a different biologic tactic. It targets an enzyme called
cathepsin K, in order to reduce osteoclast activity.
Odanacatib isn't as far along in the development process as denosumab;
odanacatib's phase lll trial is just getting under way. But two-year results
from odanacatib's phase llb trial show promise.
"That data definitely made me pay much more attention this drug,"
In the trial, postmenopausal women with osteoporosis took an odanacatib pill
or a placebo once a week. Patients don't have to take odanacatib with a meal
and they don't have to stand or sit after taking it, notes Ron Rogers, a
spokesperson for Merck, the drug company that makes odanacatib.
Two years later, women who took a weekly 50-milligram odanacatib pill had
significant gains in bone mineral density in their lumbar spine and hip. As
expected, the placebo didn't help bone mineral density.
Odanacatib's phase lll trials will test odanacatib for fracture prevention
in postmenopausal women with osteoporosis. That trial's results may be four
years away, according to Arthur Santora, MD, PhD, Merck's executive director of
Bukata says she'll be watching odanacatib's trial with interest.
"Does the bone mass gain continue to hold up in additional years on the
medication? If it does, that makes this drug very appealing," says Bukata.
"The other thing is, how did the patients tolerate it? What are the side
effects that come with it?"
In odanacatib's phase 11b trial, the drug was "generally favorable,"
report the researchers. Skin rashes, which Merck
officials say sidelined another company's cathepsin K inhibitor, didn't stand
out in the odanacatib group.
Will denosumab and odanacatib catch on, if approved by the FDA? Bukata says
that depends on how they stack up against current osteoporosis drugs.
"They have to be as good as what we have, if not better," says
Bukata. She's not just talking about effects on bones, but also side effects,
patient compliance in taking the drugs, and cost.
For instance, Bukata says that if patients are getting good results from
older osteoporosis drugs, they would "have to have a good reason" to
switch to a newer type of drug, especially if the new drug is more
Bukata predicts that most osteoporosis patients would still start treatment
with bisphosphonates or other established types of osteoporosis drugs and
try newer biologic drugs if other treatments don't work. Patients who can't
take current osteoporosis drugs, such as people with poor kidney function,
might start out on biologic drugs, Bukata says.
Bukata has no ties to Amgen or Merck. She does lecture on osteoporosis for
another drug company, Eli Lilly, on a limited basis.