Mayo Clinic Researchers Say Agent Provides Treatment Option for Women with Hot Flashes

Mayo Clinic Researchers Say Agent Provides Treatment Option for Women with Hot
Flashes

ORLANDO, May 18 /PRNewswire-USNewswire/ -- A pill used for nerve pain offers
women relief from hot flashes, Mayo Clinic researchers report at the 45th
Annual Meeting of the American Society of Clinical Oncology (ASCO).

They say the agent, pregabalin, decreased hot flash severity and frequency
about 20 percent more than did a placebo agent. Thus, pregabalin appears to
offer about the same benefit as gabapentin, an older, related drug, as well as
newer classes of antidepressants.

"Hot flashes are a major problem in many women, and for those who opt not to
take hormonal therapies or antidepressants, pregabalin appears to be another
treatment option," says the study's lead author, Charles Loprinzi, M.D., a
medical oncologist at the Mayo Clinic in Minnesota.

While pregabalin offers about the same benefit as gabapentin, women who use it
only need to take two pills a day, versus three for gabapentin, he says. Side
effects can occur with the use of either drug. However, in this study, they
were not severe enough that participants stopped using the active study drug
any more often than did patients who were taking placebos, researchers say.

Dr. Loprinzi has pioneered the field of nonhormonal hot flash therapy, which
he began researching decades ago to help breast cancer patients using
tamoxifen, an anti-estrogen treatment that creates symptoms of menopause. He
is the first researcher to test the use of antidepressants, compared to
placebo treatment, for hot flashes.

Gabapentin, an agent that has long been on the market to treat pain caused
from injury to nerves, has been shown to decrease hot flashes more than do
placebos. This drug is approved by the Food and Drug Administration (FDA) to
treat diabetic peripheral neuropathy and for shingles; anecdotal evidence
suggested that menopausal women who used it had a reduction in hot flashes,
Dr. Loprinzi says. Multiple placebo-controlled studies have since demonstrated
that this drug decreases hot flashes.

Gabapentin and a variety of antidepressants are now commonly prescribed for
treatment of hot flashes, although these agents are not specifically approved
by the FDA for such use.

Pregabalin is a newer version of gabapentin. "We thought it might also relieve
hot flashes and thus was worth testing," Dr. Loprinzi says.

So, using funds from the National Cancer Institute, Dr. Loprinzi and
colleagues set up a 207-participant study conducted by the North Central
Cancer Treatment Group (NCCTG). The study was a Phase III double-blinded,
placebo-controlled randomized trial, testing three different treatment arms: a
placebo versus daily doses of 150 milligrams (mg) of pregabalin (75 mg twice a
day) and 300 milligrams (150 mg twice a day). Patients getting pregabalin
started off with lower doses which were increased weekly to the eventual full
dose.

Participants, who reported having at least 28 hot flashes a week, kept a "hot
flash diary" in which they recorded the number and severity of hot flashes
they had each day while taking their study drug -- the content of which was
unknown to them.

In the study group, 34 percent were using anti-estrogen therapy -- either an
aromatase inhibitor, raloxifene, or tamoxifen -- to help prevent the
recurrence of estrogen-sensitive breast cancer.

The researchers found that for the 163 patients for whom information was
available, both doses of pregabalin reduced hot flashes to about the same
degree, but that toxicities, such as cognitive dysfunction, were increased at
the higher dose. Other reported side effects included weight gain, sleepiness,
dizziness, coordination troubles, concentration troubles, and concerns
regarding vision changes.

They found that, after six weeks of treatment, women using a placebo agent
reported about a 50 percent decrease in their hot flash score (severity), but
the change was greater for those who used a 75-milligram twice daily dose of
pregabalin (65 percent decrease) and a 150-milligram twice daily dose (71
percent decrease). The declines in hot flash frequency were 36 percent for
placebo users, 58 percent in women who used lower-dose pregabalin, and 61
percent in women given the higher dose.

"All in all, this study demonstrates that we have another agent to add to the
list of medications that offer benefit against hot flashes, even in women
using anti-estrogen therapies," Dr. Loprinzi says.

Pfizer, the company that manufactures pregabalin, donated both the drug and
placebo tablets for this study.

About Mayo Clinic
Mayo Clinic is the first and largest integrated, not-for-profit group practice
in the world. Doctors from every medical specialty work together to care for
patients, joined by common systems and a philosophy of "the needs of the
patient come first." More than 3,300 physicians, scientists and researchers
and 46,000 allied health staff work at Mayo Clinic, which has sites in
Rochester, Minn., Jacksonville, Fla., and Scottsdale/Phoenix, Ariz.
Collectively, the three locations treat more than half a million people each
year. To obtain the latest news releases from Mayo Clinic, go to
www.mayoclinic.org/news. For information about research and education, visit
www.mayo.edu. MayoClinic.com (www.mayoclinic.com) is available as a resource
for your health stories.

VIDEO ALERT: Additional audio and video resources, including excerpts from an
interview with Dr. Charles Loprinzi describing the research, are available on
the Mayo Clinic News Blog.

SOURCE Mayo Clinic

Karl Oestreich, +1-507-284-5005 (days), +1-507-284-2511 (evenings),
newsbureau@mayo.edu