Scientists at Imperial College London have reported positive findings from a study investigating a new class of experimental drugs, which have been shown to reduce hot flushes in menopausal women by over a third within three days.
Published in the journal Menopause, the study demonstrated the treatment’s additional beneficial effects on sleep and concentration. The Medical Research Council (MRC) and the National Institute for Health Research (NIHR) funded the research.
The trial enrolled 37 menopausal women who experienced seven or more hot flushes per day, and were aged between 40 and 62 years old. Patients were randomly assigned either 80mg of the drug MLE4901 or a placebo per day over a four-week period. Subjects then swapped treatment courses for a further four weeks.
Researchers found that MLE4901 significantly reduced the average number and severity of flushes experienced in the four-week period, compared to placebo. The compound demonstrated a significant effect within just three days, which has led the researchers to express hope that it could provide a viable alternative to Hormone Replacement Therapy (HRT).
“Ten million women in the UK and 20 million in the USA suffer with menopausal flushing,” NIHR research professor and study author Waljit Dhillo told Drug Development Technology.
“HRT is an effective treatment for their symptoms but this has an increased risk of breast cancer and as such many women cannot take – or prefer not to take – HRT. Our research shows that this could be a whole new way of treating menopausal flushing without the side effects.”
MLE4901 is thought to block the action of neurokinin B (NKB), a chemical found in the brain. Previous studies have found high levels of NKB to cause hot flushes in animal and human models.
The compound demonstrated high efficacy rates in improving flush symptoms both during the day and at night. Subjects in the trial reported an 82% decrease in the number of times flushing interrupted their sleep, and a 77% reduction in its disturbing their concentration.
“As NKB has many targets of action within the brain the potential for this drug class to really improve many of the symptoms of the menopause, such as hot flushes, difficulty sleeping, weight gain and poor concentration, is huge,” first author of the study Dr Julia Prague said.
“To see the lives of our participants change so dramatically and so quickly was so exciting, and suggests great promise for the future of this new type of treatment.”
However, the team has said further research is required to determine whether these improvements in sleep and concentration are due to less disruption from hot flushes, or if the compound also affected sleep and concentration pathways in the brain.
Despite the positive results, MLE4901 will not be taken to any further trials due to its potential adverse side effects on liver function. However, two similar compounds which also block NKB have entered large clinical trials; Ogeda’s fezolinetant (ESN364), and NeRRe spinout KaNDy’s NT-814.
“We have proven for the first time that NK3 receptor antagonists are a highly effective treatment for menopausal hot flushes,” Dhillo told Drug Development Technology.
“Two drug companies with different molecules in the same class have now also shown similar effectiveness in menopausal women. The drug companies are now carrying out larger-scale studies so that a drug could be on the market within three to five years. This is really exciting and could be a game changer for the millions of women who suffer, often in silence.”
Menopause typically occurs in women at around 45 to 55 years of age, caused by reduced levels of oestrogen. This results in a number of physical changes such as periods stopping, the inability to conceive naturally and menopausal flushing and/or sweating.