By Gene Emery

(Reuters Health) – The AbbVie drug elagolix, already used to treat the pain of endometriosis, can significantly reduce the chances of heavy menstrual bleeding caused by uterine fibroids, according to the results of two studies reported in The New England Journal of Medicine.

Uterine fibroids are non-cancerous growths in the uterus that can cause problems such as pain, pressure, heavy periods and infertility in as many as half the women who have them. They are very common, particularly among African American women.

The elagolix treatment, if approved by the U.S. Food and Drug Administration, could give women a new option for dealing with the bleeding. Current treatment sometimes involves injections given monthly or every three months. Elagolix is a pill whose effects appear and fade much more rapidly and predictably. The new studies did not directly compare the two treatments.

“This does provide a different approach and many women may prefer that,” lead study author Dr. William Schlaff of Thomas Jefferson University in Philadelphia told Reuters Health in a telephone interview. “We know it’s effective for at least six months. If that can be prolonged, it could act as a bridge to get to menopause, where hormone levels drop naturally.”

“But if you’re 32 years old (with a fibroid bleeding problem) this may not be a bridge you want to use for 20 years,” he said. Such women may want to consider a hysterectomy or some other option.

The two new studies – which were identical – followed a total of 790 women with a menstrual blood loss of more than 80 milliliters (about 2.7 ounces) per month.

At the six-month mark, among women getting placebo treatment, 8.7% in one study and 10% in the other saw their monthly blood loss reduced by at least 50%.

When the women were given elagolix alone, the success rates were 84.1% in one study and 77% in the other.

The treatment suppresses ovarian sex hormones, increasing the odds of osteoporosis. So in some women, doctors also gave hormone therapy to compensate.

With that hormonal “add-back therapy,” monthly flow was still reduced by at least 50% in 68.5% of women in one study and in 76.5% in the other.

Add-back therapy alleviated decreases in bone mineral density caused by elagolix but it also increased the number of hot flushes in both trials, and in one trial, it increased the likelihood of spotting between periods, the researchers found.

Most side effects of the drug “were considered by the investigators to be mild or moderate in severity,” they reported.

The studies, known as Elaris UF-1 and Elaris UF-2, were financed by AbbVie, which sells the drug under the brand name Orilissa.

The 300-milligram twice-daily elagolix treatment would cost more than $47,000 per year, according to prices on In contrast, monthly leuprolide injections, which are an established treatment, costs roughly $7,000 per year.

Compared with placebo recipients, elagolix recipients with add-back therapy also had higher levels of the oxygen-carrying protein hemoglobin in their blood and were more likely to have their periods cease altogether.

They also tended to score higher on quality of life questionnaires.

Schlaff, who chairs the department of obstetrics and gynecology at Thomas Jefferson, predicted that if the drug is approved for fibroid bleeding, it will change the way women are treated.

“A lot of women want to use oral medication” instead of periodic injections, he said. “Women are going to say, ‘I don’t want to commit to a 1- or 3-month dose.’ Or they may want to start with one and move to another.”

(This story has been refiled to correct brand name of drug in paragraph 12)

SOURCE: The New England Journal of Medicine, online January 22, 2020.