London | Reuters — European drug regulators launched a review on Jan. 11 of the use in farming of a key last-line antibiotic called colistin, after international research found alarming evidence of a gene that makes bacteria resistant to the drug.
The London-based European Medicines Agency (EMA) said it was responding to a European Commission request to update its advice on the use in animals of colistin, which is one of the last-resort antibiotics capable of treating humans with certain bacterial infections.
“Because of (colistin’s) important role as a last defence against antimicrobial-resistant bacteria, the agency will consider if its 2013 advice on the responsible use of colistin in animals, particularly pigs, needs to be updated in light of the recent discovery,” EMA said in a statement.
Colistin has been used for more than 50 years in both animals and people.
In human medicine it is now used as a last-resort for the treatment of people with different kinds of infections caused by multidrug-resistant bacteria, or “superbugs.”
Scientists around the world voiced alarm last year at the discovery in China of a new gene that makes bacteria highly resistant to polymyxins — a class of antibiotics that includes colistin and is widely used in livestock farming.
In Europe 80 per cent of polymyxin sales — mainly colistin — are in Spain, Germany and Italy, according to EMA’S Surveillance of Veterinary Antimicrobial Consumption (ESVAC) report.
Worldwide demand for the antibiotic in agriculture is expected to reach almost 12,000 tonnes per year by the end of 2015, rising to 16,500 tonnes by 2021, according to a 2015 report by the QYResearch Medical Research Centre.
EMA said it would reconvene its Antimicrobial Advice Ad Hoc Expert Group, which issued its previous advice on colistin in 2013, to re-evaluate that guidance, and expects to finalize the update over the next six months.
In Canada, the federal health department’s Veterinary Drugs Directorate places polymyxins in Category I (“very high importance”) of its list of antimicrobials based on their importance in human medicine.
Health Canada announced in October that Polymyxin B, which is approved for veterinary use, is to be added to Canada’s Veterinary Prescription Drug List in early April 2016.
Certain uses of the drug would then require a veterinarian’s prescription, so as “to reinforce prudent use of this class of drugs.”
The drugs to be affected by the ruling include Special Formula 17900-Forte Suspension, a Zoetis product to treat mastitis in dairy cattle, and three ointment products sold for use on dogs and cats.
— Reporting for Reuters by Kate Kelland in London. Includes files from AGCanada.com Network staff.