With news of a HRT alternative for women struggling with hot flushes now available on the NHS, Dr Louise Newson explains why when it comes to Fezolinetant, women need to proceed with caution.
UK medicines regulator NICE reported that they’re in the final stages of recommending drug Fezolinetant to help treat hot flushes in menopausal women, with this reported widely by the UK media. As a physician, and as a woman who knows firsthand the impact of low hormones, these headlines aren’t telling the full picture.
Menopause is not a single-symptom issue
Fezolinetant will only target the vasomotor symptoms of hot flushes and night sweats, but these aren’t actually the most common. Out of 131 million symptom logs on my free Balance app, the most common menopause symptom recorded is actually brain fog, followed by anxiety and low mood – which is why tracking your hormone health across your whole body matters far more than targeting a single symptom. Hot flushes were actually number 10 and night sweats way down at the 34th.
Whilst hot flushes can be a debilitating menopause symptom, it’s far from the only one. Women tend to experience several symptoms, both physical and psychological. Instead, we must look at the whole-body impact of low hormones.
We don’t have enough data on this drug yet
There have not been studies comparing HRT (which is the gold standard treatment for menopausal symptoms) with fezolinetant or elinzanetant. Also there have not been any long-term studies involving women who have had breast cancer taking either of these drugs. This is why it is not currently recommended for use in women with current breast cancer, or liver disease, as the safety and efficacy are unknown.
Fezolinetant won’t address the health risks associated with menopause
The drug won’t address other key health risks associated with menopause: such as improving your bone density; reducing inflammation and protecting our brains and cardiovascular system from the effects of low hormones. There are risks to both symptoms and future health if hormone treatments (containing progesterone, estradiol and testosterone) are not prescribed to women. Women should have more education and knowledge about this.
The drug comes with other potential side effects
In a clinical trial, 2.1% of women taking fezolinetant developed signs of liver damage (elevated levels of liver enzymes) that resolved when the drug was stopped, which is why liver function must be monitored before and during treatment in all patients taking fezolinetant.
One paper reported an increased incidence of cancer in women treated with fezolinetant compared with placebo . This is a concern as currently this drug is being marketed as a drug to prescribe to women who have had breast cancer in the past.
Fezolinetant works by blocking a specific receptor called the neurokinin-3 receptor, which helps transmit signals from KNDy neurones. By blocking this receptor, this drug reduces the activity of these neurones and may help relieve hot flushes.
However, neurokinin receptors are not only found in the hypothalamus: they also exist in other parts of your brain, your spinal cord, and in organs such as your ovaries and womb, as well as in your digestive, cardiovascular and immune systems. Because of this, blocking these receptors is likely to affect other body functions. And importantly, the full effects of blocking them throughout the body are not yet completely understood.
Fezolinetant also blocks a protein called kisspeptin which has many beneficial effects in your body. It can work to stop cancer spreading. It also works to increase amounts of progesterone, estradiol and testosterone in the brain so blocking it leads to even lower levels of these hormones in your brain
The verdict
As a physician, these headlines trouble me for a number of reasons. There are risks to both symptoms and future health if hormone treatments (containing progesterone, estradiol and testosterone) are not prescribed to women. Women should have more education and knowledge about this.
It’s easy to take headlines at face value, but I firmly believe every woman has the right to work with their healthcare team on finding a treatment that is right for them, rather than closing the door on hormones to half a million women.
