Health Canada has officially sanctioned Elinzanetant, branded as Lynkuet, as a therapeutic option for women enduring moderate to severe hot flashes and night sweats due to breast cancer. Originally given the green light in July 2025 for menopausal symptoms in women, recent studies have confirmed its efficacy for those undergoing treatment for breast cancer. The new authorisation, which came into effect on Friday, marks a significant advancement in supportive care for this patient demographic.
The Challenge of Hormonal Treatments
Approximately two-thirds of breast cancers are classified as hormone-receptor positive, indicating their reliance on estrogen for growth. Consequently, oncologists often prescribe anti-estrogen therapies to control these cancers, which can inadvertently trigger bothersome vasomotor symptoms, including hot flashes and night sweats.
Elinzanetant, developed by Bayer, offers a non-hormonal alternative that specifically targets hyperactive neurons that can be stimulated by diminished estrogen levels. Dr. Christine Brezden-Masley, medical director of the cancer programme at Sinai Health in Toronto, emphasised the limitations faced by breast cancer patients, who cannot opt for traditional hormone replacement therapy typically available to menopausal women.
“The clinical trial assessing elinzanetant was groundbreaking, being the first to focus on breast cancer patients under anti-estrogen treatment,” Dr. Brezden-Masley remarked, acknowledging her consultancy role with Bayer.
A Long Road to Relief
Women diagnosed with breast cancer often endure anti-estrogen treatment for anywhere between five to ten years. The most commonly prescribed medications include tamoxifen and aromatase inhibitors, as noted by the Canadian Cancer Society. In some cases, chemotherapy may also induce menopause by ceasing ovarian function.
The consequences of hot flashes and night sweats extend beyond mere discomfort; they can severely disrupt daily functioning and impair sleep quality. Moderate hot flashes are characterised by sensations of intense heat accompanied by sweating, while severe instances can be so disruptive that they halt normal activities.
Oncologists are keenly aware of the need to manage these symptoms effectively, as some patients resort to discontinuing their cancer treatments in a desperate bid for relief. “Our priority is to address all symptoms so that patients adhere to their prescribed therapies, reducing the risk of cancer recurrence,” Dr. Brezden-Masley stated.
Historically, breast cancer patients have had few options for alleviating these symptoms. Doctors have occasionally resorted to prescribing medications off-label, such as the anticonvulsant gabapentin and the antidepressant Effexor, in an effort to provide some relief.
Patient Perspectives
Laurie Legere, a 47-year-old hospital administrator from Toronto, shared her challenging experience as she navigated her breast cancer treatment. After discovering a lump shortly before her 44th birthday, she underwent chemotherapy to shrink the tumour before surgery. This treatment initiated a series of disruptive hot flashes that plagued her daily life and sleep.
“The hot flashes were extremely disruptive, affecting my ability to concentrate during meetings and presentations,” Legere recounted. “Sleep became elusive, which is critical when you’re trying to heal.” As she continues her endocrine therapy, Legere has faced limited success with existing medications, often suffering from intolerable side effects.
Currently, she is hopeful about Elinzanetant, having already secured a prescription, as she anticipates a more manageable experience with her symptoms.
Clinical Validation and Future Implications
The approval of Elinzanetant was bolstered by Bayer’s OASIS-4 study, a Phase 3 randomised, placebo-controlled trial involving 395 women aged 18 to 70, all receiving endocrine therapy for breast cancer. Participants reported experiencing at least 35 moderate to severe hot flashes or night sweats weekly. Results indicated a substantial reduction in both hot flashes and sleep disturbances among those administered Elinzanetant compared to the placebo group.
Common side effects reported included daytime drowsiness, fatigue, and gastrointestinal issues, yet an impressive 91.6 percent of participants chose to continue their treatment for an additional two years following the trial’s conclusion.
While Bayer has not yet disclosed the cost of Elinzanetant, it is important to note that it is currently not publicly funded in Canada.
Why it Matters
The introduction of Elinzanetant as a treatment option for breast cancer patients grappling with hot flashes and night sweats is a groundbreaking development in oncology care. It fills a critical gap for women who have long suffered from these debilitating symptoms without adequate relief. As healthcare systems continue to evolve, this advancement underscores the importance of addressing the holistic needs of patients, ultimately improving their quality of life during and after cancer treatment.
