Alcohol treatment drug nalmefene 'not effective'
A drug to treat alcohol problems was licensed for use in the UK despite insufficient evidence it was effective, researchers in Scotland have found.
Nalmefene was approved for use in Europe in 2013 and then recommended by NICE (National Institute for Health and Care Excellence).
But scientists at the University of Stirling found issues with the clinical trials and the way they were analysed.
NICE said there was evidence to recommend it in specific circumstances.
The university said the way the trials had been conducted made it impossible to know how much the drug - marketed as Selincro - actually helped to reduce drinking in patients dependent on alcohol.
Scientists analysed the published studies that formed the basis of the European licensing and the decision by NICE.
They concluded the evidence of its effectiveness was "weak" and that any possible effect on patients was small - about a one drink per day reduction on average.
The research, published in the journal Addiction, also found nalmefene was more expensive than similar drugs on the market and that no comparison with these alternatives was made.
Dr Niamh Fitzgerald, a pharmacist and lecturer in alcohol studies at the university, said: "It's vitally important that we know that prescribed drugs are effective in treating the intended problem.
"In this case, we found problems with the registration, design, analysis and reporting of these clinical trials which did not prevent the drug being licensed or recommended for use.
"We believe this creates a difficulty for doctors trying to treat alcohol dependence and throws up critical questions for regulators around why a drug was licensed without a bank of high quality, reliable evidence."
The drug is currently licensed to be used in conjunction with psychosocial support.
It is intended to reduce alcohol consumption in patients diagnosed with alcohol dependence, with consistently high alcohol consumption levels, but who do not experience physical withdrawal symptoms when they stop drinking.
Prof Carole Longson, director of the Centre for Health Technology Evaluation at NICE, said: "Nalmefene was recommended within its marketing authorisation by the regulator in 2013, where the European Medicines Agency (EMA) rigorously reviewed it's safety and efficacy before approval - as it does with all medicines under evaluation.
"Our appraisal process for nalmefene thoroughly interrogated the evidence base and, as is the standard with all our appraisals, we engaged with and took into account submissions from a multitude of stakeholders.
"When presented with the evidence, including the analysis of the clinical studies, the independent committee concluded that there was sufficient evidence to recommend nalmefene in specific circumstances."