The drug, called linzagolix and prescribed under the brand name Yselty in Europe, is administered orally and can be dosed according to a patient’s exact needs.
“Fibroids are one of the most common conditions that effect women—it’s the number one reason for hysterectomy—and the treatments we have now just aren’t satisfactory,” study co-author Hugh S. Taylor, MD, professor and chair of Obstetrics, Gynecology, & Reproductive Sciences at the Yale School of Medicine, told Verywell, adding that many medications that are currently used “just treat the symptoms—not the fibroids themselves.”
Results for the latest trial for linzagolix were published in The Lancet. For the trial, researchers enrolled around 500 women who were diagnosed with uterine fibroids and experienced heavy, irregular bleeding. Some patients were given linzagolix and some were given a placebo.
After 24 weeks, the researchers found that patients who received linzagolix had less bleeding than those taking the placebo.
Patients who took the medication plus hormone add-back therapy (which “adds back” in small doses of hormones that are removed by the drug to prevent side effects like bone loss) had a 75% and 93% response rate across the two trial groups.
Those who were treated with linzagolix but did not take add-back therapy had at least a 50% response.
The researchers concluded that linzagolix with or without add-back therapy “significantly reduced heavy menstrual bleeding,” noting that the drug “potentially provides a unique option for the chronic treatment of symptomatic uterine fibroids in women who cannot or do not want to” take add-back therapy.
“The hope is that linzagolix will give better long-term control than anything we have today, but also prevent the fibroids from growing so we don’t have to kick the can down the road and deal with the problem later on when the fibroids are bigger,” Taylor said.
What Are Fibroids?
Uterine fibroids are non-cancerous growths that develop from the muscle tissue of the uterus. They’re the most common growth found in the pelvis of people with a uterus. They can cause uncomfortable symptoms, including:
Longer, more frequent or heavy periodsCrampsVaginal bleeding at times other than during periodsAnemiaPainPressureEnlarged uterus and abdomenMiscarriagesInfertility
Uterine fibroids that are small or don’t cause symptoms may not need to be treated. Others may be treated with medication like hormonal birth control pills, gonadotropin-releasing hormone (GnRH) agonists, GnRH antagonists with hormonal add-back therapy, a progestin-releasing IUD, or tranexamic acid.
Fibroids may be removed via surgery known as myomectomy and, in more severe cases when no other treatments have worked, patients may consider having a hysterectomy.
Why a Medication Like Linzagolix Is Needed
Linzagolix is an oral drug and GnRH antagonist that hinders the production of estrogen, Taylor explained. The medication specifically targets bleeding caused by uterine fibroids, and shrinks the fibroids themselves.
Linzagolix is a GnRH antagonist, and there are already GnRH antagonists on the market. However, doctors can tailor how much estrogen is blocked with linzagolix to meet a patient’s needs without putting them into menopause. Induced menopause is a common with other GnRH antagonists and can lead to complications like bone loss, Taylor said.
The drug also doesn’t need to be used with hormone add-back therapy.
“It still does a pretty good job of controlling the bleeding without it,” Taylor said. “For those women who don’t need those extra hormones, it could be a real advantage.”
The drug is “very promising,” said women’s health expert Jennifer Wider, MD. “Having a medication that can help lessen heavy bleeding is a great addition to the options to treat and manage uterine fibroids,” she said.
Linzagolix is currently approved for use in the European Union but not in the U.S. However, Taylor said he is anticipating that, at some point, it will get FDA approval.
