Bayer's Elinzanetant Shows Promise in Alleviating Breast Cancer Treatment Side Effects

Bayer has unveiled promising results for its experimental drug elinzanetant, demonstrating its potential to address a significant unmet need in breast cancer treatment. The non-hormonal medication has shown efficacy in reducing vasomotor symptoms associated with endocrine therapy, a common treatment for hormone receptor-positive breast cancer.

Oasis-4 Trial Results

The Phase 3 Oasis-4 trial, presented at the American Society of Clinical Oncology's annual meeting, evaluated elinzanetant's effectiveness in managing vasomotor symptoms in women receiving endocrine therapy for breast cancer. The study involved 473 participants, with 316 receiving elinzanetant and 157 receiving a placebo.

Key findings from the trial include:

• After one month, 61% of women taking elinzanetant reported at least a 50% reduction in the frequency of daily moderate-to-severe vasomotor symptoms.
• At three months, women on elinzanetant experienced greater improvements in sleep and quality of life compared to those on placebo.
• The drug demonstrated rapid symptom alleviation at both weeks 4 and 12 compared to placebo, meeting the study's primary goal.

Dr. Fatima Cardoso, the study's lead investigator and director of the breast cancer unit at the Champalimaud Cancer Center in Lisbon, Portugal, emphasized the unmet medical need, stating, "With no currently approved treatments for this indication, there is an unmet medical need for therapeutic options."

Mechanism of Action and Safety Profile

Elinzanetant targets two receptors, NK1 and NK3, which play a role in regulating body temperature. This non-hormonal approach is particularly significant for breast cancer patients, as hormone replacement therapies typically used for menopausal symptoms can increase the risk of disease progression or recurrence.

The safety profile of elinzanetant appears promising:

• In the Oasis-4 trial, 70% of women taking elinzanetant reported at least one adverse event, compared to 62% in the placebo group.
• Most common side effects included fatigue, headache, and drowsiness.
• Eight women treated with elinzanetant reported serious adverse events.

Importantly, no increased risk of liver toxicity was observed, a concern that has been reported with another drug in this class, Astellas Pharma's Veozah.

Potential Impact on Breast Cancer Treatment

Vasomotor symptoms, including hot flashes and disrupted sleep, affect nearly 90% of women with early breast cancer who are treated with endocrine drugs. These side effects can be severe enough to cause some patients to discontinue treatment, potentially impacting disease progression and survival rates.

Dr. Yesmean Wahdan, vice president of U.S. medical affairs for Bayer's women's health unit, highlighted the significance of this development: "It's due time that new innovation comes into this space. [This therapy] really aims at targeting the source of what's causing the symptoms that are happening as the woman goes through the menopausal transition and into menopause."

If approved for women experiencing vasomotor symptoms due to breast cancer treatment, elinzanetant would be the first therapeutic of its kind. This breakthrough could potentially improve treatment adherence and quality of life for breast cancer patients undergoing endocrine therapy.