Inferior TB drugs pose risks to health
Substandard tuberculosis drugs sold by pharmacies in poor countries are a growing public-health threat, but the problem could be alleviated if governments enforced World Health Organization standards, a new study reports.
The New York Times
Substandard tuberculosis drugs sold by pharmacies in poor countries are a growing public-health threat, but the problem could be alleviated if governments enforced World Health Organization (WHO) standards, a new study reports.
At pharmacies in 17 countries, the authors bought 713 samples of two TB drugs, the antibiotics rifampin and isoniazid. Nine percent had no active ingredient or, worse, too little: An inadequate dose encourages the growth of drug-resistant TB strains while also failing to cure the patient.
The study, published online by PLOS Medicine, shows the failures in what should be a nearly perfect system for basic TB control, said Dr. Lucica Ditiu, executive secretary of the Stop TB Partnership.
That partnership, which is affiliated with WHO, supplies a packaged, six-month supply of high-quality drugs at about $30 a box. Poor countries get them free, middle-income countries pay on a sliding scale, and the U.S. is negotiating to buy them to cover spot shortages, Ditiu said.
Ideally, said Amir Attaran, a drug-counterfeiting expert at the University of Ottawa and an author of the study, all countries would buy the partnership’s drugs, and governments would ban sales of those drugs for other purposes.
“But that’s not what happens,” Attaran said. Not all countries follow the WHO regimen, not all doctors prescribe the drugs in it, “and in private pharmacies, all bets are off,” he added, since some will sell anything to any buyer, with or without a prescription.
Even poor countries such as Rwanda have shown they can control TB by enforcing “pharmacovigilance,” the study said. Attaran and Ditiu cited India as a country that conspicuously fails to enforce it and so is facing a huge epidemic of multidrug-resistant TB.