A “game-changing” wonder drug could reduce hot flushes in menopausal women by up to three quarters, a study by Imperial College Research suggests.
Scientists said the “exciting” findings could offer hope to hundreds of thousands of women who are plagued by symptoms which left many sleep-deprived, anxious and depressed.
Each year around 1.5 million women experience menopausal symptoms, including 400,000 who suffer them to a troublesome extent.
But many shun hormone replacement therapy, because it has been linked with an increased risk of breast cancer and blood clots.
The study published in The Lancet found that a new drug was able to reduec the number of women suffering seven or more hot flushes a day by as much as 73 per cent.
The treatment also reduced their severity and impact, the research found.
Scientists said women taking part in the trial said they felt “human again” after suffering distressing and debilitating symptoms for years.
The average menopause lasts for seven years, and four in five women will suffer hot flushes.
The new drug compound called MLE4901, tested on women who suffered severe flushing, works by targeting receptors in the brain, blocking a chemical called neurokinin B (NKB).
Researchers said it could offer hope to women who were currently enduring misery, but avoiding HRT because it was unsuitable or nor preferred because of safety concerns.
The new study, funded by the Medical Research Council and the National Institute of Health Research
involved women with severe flushing, who were given the drug to try to relieve their symptoms.
Author Professor Waljit Dhillo, from the Department of Medicine at Imperial, said: "If a woman is having more than seven flushes a day and the drug is getting rid of three-quarters of them, that's pretty life-changing.
"For day to day living and work, that's a significant impact on quality of life. If we can reduce flushing by 73 per cent it's a game-changer for those patients."
The randomised, double-blind, placebo-controlled trial, involved 28 menopausal women aged between 40 and 62 years old - and who experienced seven or more hot flushes a day and had not had a period in at least 12 months.
Participants were randomly chosen to either first receive a 80 mg daily dose of the drug compound, originally developed by AstraZeneca and licensed to Millendo Therapeutics, or a placebo over the course of four weeks - before switching to receive the other tablet for a month.
The researchers found that the compound MLE4901 significantly reduced the average total number of flushes during the four-week treatment period, as well as their severity, compared to when the patients received the placebo for four weeks.
It also helped to reduce the impact of flushes on the women's lives, improving sleep, the findings,
presented to the annual meeting of the Endocrine Socieyt, in Florida, showed.
Professor Dhillo said: "A lot of women are choosing not to take HRT because it is oestrogen-based. This new drug is a pill which blocks the NK3 receptor, so it won't have the side effects associated with oestrogen."
He said the findings, from the proof of concept study would now need to be tested over the long term in a larger group of patients.
For many menopausal women, hot flushes are an uncomfortable inconvenience.
But a significant number suffer to such an extent that bed sheets end up drenched in sweat, while relentless insomnia can leave them struggling to cope during the day.
Analysis of brain tissue from post-menopausal women has previously revealed elevated levels of NKB in their brains, while giving the chemical to younger patients has been found to induce flushing.
Dr Julia Prague, first author of the study, commented: "Despite the fact that for millions of women their menopausal symptoms are intolerable so many are suffering in silence because it is a taboo subject and treatment options are limited.
“It was so exciting to see the lives of those who participated in the study become transformed when their flushes improved once taking the new drug. They could sleep through the night, and be less embarrassed in the daytime; they told me they felt 'human again'."
Elaine Barker, aged 61, one of the participants in the study, said she enrolled in an attempt to combat daily and nightly hot flushes. “Anything that could improve the quality of my life would be worthwhile,” she said. “When taking the tablets my flushes noticeably reduced and I woke less often at night and my quality of sleep improved.”