A drug combination which could cure treatment-resistant gonorrhoea has been identified by scientists.
Researchers believe antibiotic gentamicin could act as a back-up option to treat the sexually-transmitted infection amid rising concern that resistance to treatment might become widespread.
The drug, taken with azithromycin, worked almost as well as the current first-line treatment, ceftriaxone and azithromycin, according to a study published in The Lancet journal.
However, gentamicin was less effective against throat or rectal gonorrhoea.
Professor Jonathan Ross, chief investigator from the University of Birmingham, warned the existing treatment “is beginning to fail”.
Two women had been infected with super-gonorrhoea, which was resistant to the first-choice treatment, Public Health England (PHE) confirmed earlier this year, while other cases have previously been reported.
Gonorrhoea does not usually lead to complications, but if left untreated can cause serious health issues including pelvic inflammatory disease among women.
In a trial at 14 sexual health clinics in England, funded by the National Institute for Health Research (NIHR), 720 patients were given either the current antibiotic treatment of ceftriaxone or gentamicin.
Both groups were also given an oral dose of azithromycin.
A total of 98% of those given ceftriaxone had their gonorrhoea cured after two weeks, compared to 91% of those treated with gentamicin.
The findings suggest gentamicin could offer an alternative for patients, if they do not respond to the first-choice treatment.
“Our current antibiotic treatment for gonorrhoea is beginning to fail and experience with previous drugs strongly suggests that this could become a widespread problem,” Ross said.
“Our trial has found that gentamicin combined with azithromycin works almost as well as ceftriaxone with azithromycin for genital gonorrhoea, but did not clear throat or rectalgonorrhoea as effectively.
“We believe ceftriaxone should remain the first-line treatment for gonorrhoea, with gentamicin as an alternative, particularly for patients with genital infection and those who are allergic or intolerant to ceftriaxone.”
The researchers said further work is needed to find alternative treatments, with antibiotic resistance a growing problem.
Professor Hywel Williams, director of the NIHR’s health technology assessment programme, said: “It’s very worrying that cases of treatment-resistant gonorrhoea are now appearing across the globe.
“This research provides important new evidence that suggests that gentamicin with azithromycin could become a second-line treatment for patients who are resistant to ceftriaxone with this infectious disease.
“The NIHR is committed to research in areas of greatest health need, such as antimicrobial resistance.
“This research is one of a number of studies we’ve funded over the last few years in this vital area, in our sustained effort to tackle this worldwide threat.”