Pfizer’s pain drug helps reduce hot flashes
Lyrica: reduced instance of hot flashes and their intensity. Photo: Bloomberg
Friday May 15 2009
Pfizer Lyrica, a treatment for nerve pain and seizures, lowers the incidence of hot flashes in women, a study shows.
After six weeks of treatment, 61pc of those on the highest Lyrica dose had fewer hot flashes, compared with a third of patients on a placebo. The Lyrica patients also reported a 71pc decrease in severity of the hot flashes, compared with a 50pc decrease in those given a placebo, according to data from the Mayo Clinic.
Lyrica generated revenue of $2.6bn in 2008 for New York-based Pfizer. The drug is approved to treat nerve pain tied to shingles and diabetes, to help control seizures caused by epilepsy and also for fibromyalgia, a muscle pain disorder.
“Hot flashes are a major problem in many women,” said Charles Loprinzi, an oncologist at the Mayo Clinic in Minnesota, and the study’s lead author, in a statement. The results provide options for women who don’t want to take a hormone or an antidepressants to treat the hot flashes.
“Lyrica is not FDA approved for the treatment of hot flashes, but Pfizer and independent researchers continue to investigate potential new uses,” said Sally Beatty, a Pfizer spokeswoman, in a telephone interview yesterday.
About 34pc of the women were using an anti-estrogen therapy to help cure their breast cancer. Participants were asked to record the number and severity of their hot flashes while enrolled in the study. Side effects included weight gain, sleepiness, dizziness, difficulty with concentration and vision changes. A total of 163 women were evaluated in the trial.
Some breast cancer drugs work by blocking estrogen, a hormone that breast tumor cells need to grow. When estrogen levels drop, the part of the brain responsible for temperature control malfunctions, doctors say. Hot flashes strike suddenly and can be accompanied by rapid heart beat, nausea, dizziness, headaches, muscle fatigue and weakness.
Physicians have prescribed Wyeth’s Effexor and other drugs in its class, known as SNRIs or serotonin norepinephrine reuptake inhibitors, most often to treat hot flashes in women with breast cancer. This family of medicines isn’t approved to relieve hot flashes, but is commonly used for this purpose, said Loprinzi.
Antidepressants in the same family of medicines as Effexor work by boosting levels of two brain chemicals, serotonin and norepinephrine, that help carry signals between neurons. Older studies have linked hot flashes to a deficiency of serotonin, which also regulates body temperature.
Wyeth’s hormone replacement therapies Premarin and Prempro were the most widely prescribed treatment for hot flashes before September 2002, when a US study linked the therapies to breast cancer, heart attacks and strokes.
Some patients now take lower doses of Premarin and Prempro to limit their exposure to the hormones. Prempro is a combination pill that uses progestin to reduce the risk of uterine cancer that is linked to using estrogen alone. Premarin, an estrogen-only pill, is given to women who have had hysterectomies, or removal of the uterus.
The study was released ahead of a meeting of the American Society of Clinical Oncology, which will run May 29 to June 2 in Orlando, Florida.
(Bloomberg)
- Elizabeth Lopatto and Lisa Rapaport
