Health Canada approves drug to treat hot flashes for some cancer patients

Health Canada has authorized a drug to treat moderate to severe hot flashes and night sweats in breast cancer patients.

Elinzanetant, also known by the brand name Lynkuet, was first approved in July 2025 to treat the symptoms in women going through menopause, but another study reviewed by the department has since shown effectiveness of the drug specifically in breast cancer patients.

According to Health Canada’s drug database, the new market authorization took effect on Friday.

About two-thirds of breast cancers are hormone-receptor positive, meaning they need estrogen to grow. Oncologists treat those cancers by blocking the body’s production of estrogen, often triggering vasomotor symptoms such as hot flashes and night sweats.

Elinzanetant — manufactured by Bayer — is a non-hormonal medication that reduces those symptoms by directly targeting neurons that can become hyperactive with a lack of estrogen. Dr. Christine Brezden-Masley, medical director of the cancer program at Sinai Health in Toronto, said women with breast cancer have had limited options to help with hot flashes and night sweats because they can’t take hormone replacement therapy like other women in menopause might.

“The clinical trial with elinzanetant was the very first one that actually looked at breast cancer patients on anti-estrogen therapy,” said Brezden-Masley, who receives compensation as a consultant to Bayer.

Breast cancer patients generally have to stay on anti-estrogen pills — also called endocrine therapy — for about five to 10 years, she said.

The most commonly used anti-estrogen medications are tamoxifen and aromatase inhibitors, according to the Canadian Cancer Society.

Chemotherapy can also put patients into menopause by stopping the ovaries from working, Brezden-Masley said.

Hot flashes and night sweats interfere with women’s ability to function during the day and interrupt their sleep at night.

Moderate hot flashes are defined as the feeling of heat along with sweating. Severe hot flashes are the same, but so bad they cause women to stop what they’re doing.

They can be so debilitating that some patients stop taking their cancer medication to halt the symptoms — something oncologists want to prevent, Brezden-Masley said.

“We work closely with them to ensure that we deal with all of those symptoms to ensure that they adhere to their breast cancer therapy so we don’t have breast cancer recurring.” That has included prescribing some drugs off-label — including anticonvulsant gabapentin and anti-depressant Effexor — to try to give their patients some relief.

“We’ve been kind of pulling old drugs that would have, you know, a little bit of a benefit for our patients and decrease their hot flashes,” she said.