Study backs new drug for typhoid in poor countries

A large trial comparing treatments for typhoid has backed the use of gatifloxacin, an antibiotic launched by Bristol Myers Squibb in the United States but withdrawn amid worries about side effects.

The trial, conducted in Kathmandu, Nepal, analyzed gatifloxacin, which is available as a generic in Asia, against chloramphenicol, the standard treatment for typhoid since the 1950s—and found both drugs to be equally effective.

But researchers found the side effects from the older drug were significantly worse, and their findings have prompted them to ask the World Health Organization (WHO) to recommend gatifloxacin for certain patients in developing countries.

“We’re trying to gather evidence in favor of this drug for certain clear-cut indications in the developing world,” said Dr Buddha Basnyat of the Oxford University Clinical Research Unit and Patan Academy of Health Sciences in Kathmandu, whose study was in the Lancet Infectious Diseases journal on Friday.

“In South Asia…typhoid is a very common and rampant problem. We’re running out of antibiotics, and this looks like a very affordable drug,” he said in a telephone interview.

Typhoid—also known as enteric fever—is a bacterial disease caused by Salmonella typhi and Salmonella paratyphi.

It is transmitted by ingesting food or drink contaminated by the faeces or urine of infected people. It causes around 26 million infections a year and more than 200,000 deaths, and the number of cases is particularly high in parts of South Asia.

The spread of multi-drug-resistant forms of the typhoid-causing bacteria means there is a constant need to find effective new treatments.

Gatifloxacin was launched in the United States by BMS under the brand name Tequin, but was then withdrawn after a Canadian study in 2006 suggested the drug can cause serious side effects including very high and low blood sugars. U.S. drugmaker Allergan produces an eye-drop formulation of the drug called Zymar which is used to treat bacterial conjunctivitis.

Basnyat’s team found no difference between gatifloxican and chloramphenicol in terms of treatment failure and the time to clear the fever, but the side effects—including anorexia, nausea, diarrhea and dizziness—were significantly worse in patients being treated with chloramphenicol.

Because of worries about side effects from gatifloxacin, the researchers closely monitored blood sugar levels. A higher number of patients had raised blood sugar during the first week of treatment, they said, but this had returned to normal once the treatment had ended and no change in treatment was needed.

“Although there have been concerns of the side effects of gatifloxacin in elderly people from North America, this was amongst a very different population to those needing the drug in the developing world,” said Basnyat.

He said the average age of the patients in the Nepal study, which involved 844 children and adults, was around 15 or 16 years, and none had diabetes risk.

The researchers said another advantage of gatifloxacin was that it is taken only once a day for seven days, with an average cost for a treatment course coming to $1.50. Chloramphenicol is taken four times a day for 14 days, costing around $7.

The team has now submitted their evidence to the WHO, arguing that gatifloxacin should be recommended for use in young people who are not at risk from diabetes.

(Editing by Sophie Walker)

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By Kate Kelland

LONDON