International Groups Launch Attack on Drug-Resistant TB

By John Gever
GENEVA, 2 july 2008-- State-of-the-art diagnostic tests for multidrug-resistant tuberculosis, as well as drugs for treating it, will be made available to certain African and Asian nations under two new programs announced here.
Led by the World Health Organization, the programs will spend $26 million to deploy rapid molecular tests for MDR-TB in 16 countries in Africa and central and south Asia over the next four years.
Another $34 million will go to purchase drugs to treat MDR-TB in those countries and 38 others where the disease is endemic.
The new tests will shorten to two days the time needed to determine whether a given TB strain will respond to standard first-line drugs -- rifampicin and isoniazid. Standard culture-based methods now used in developing countries typically require three to four months to yield results.
The PCR-based line probe assays were developed by two European companies, Hain Lifesciences in Germany and Innogenetics in Belgium. The latter's assay detects rifampicin-resistant TB strains. Hain's can identify resistance to both drugs.
Both assays are commercially available in Europe and other countries, but not the United States.
In a telephone press conference, Richard O'Brien, M.D., of the Foundation for Innovative New Diagnostics, one of the sponsors of the new initiative, said Hain is now in discussions with the FDA about having its assay approved in the U.S.
Dr. O'Brien said Innogenetics had not expressed interest in FDA approval for its product.
He said that although the new initiative does not directly affect the U.S. or other developed countries, the new tests could improve TB testing there as well.
"Any country that has a possibility of having a patient with MDR-TB should consider using [these tests]," he said.
He added that the American Thoracic Society, the Infectious Disease Society of America, and the CDC are updating their joint TB diagnostic statement to recommend use of rapid molecular tests for MDR-TB.
A WHO committee last month recommended full-scale implementation of the Hain and Innogenetics tests following a successful field trial in South Africa. It showed that the tests were accurate and feasible under real-world conditions in a developing country, the committee's report said.
The drug-purchase program will focus on currently approved second-line TB drugs known to be effective against MDR-TB, said Salmaan Keshavjee, M.D., of Brigham and Women's Hospital in Boston. Dr. Keshavjee chairs WHO's Green Light Committee, which negotiates prices of drugs with producers and develops guidelines for treatment of drug-resistant TB.
Money for both programs will come from UNITAID, an international organization funded by a tax on airline tickets levied by France, Chile, South Korea, and several African nations. Brazil and more than a dozen other countries, mainly in Africa, are expected to follow suit soon.
Neither program will be addressing the growing problem of extensively drug-resistant TB, in which second-line drugs are also ineffective, according to Mario Raviglione, M.D., director of the WHO's Stop TB Department. An estimated 40,000 cases are now seen worldwide annually.

WHO Finds Global Drug-Resistant TB at Record Levels

By Peggy Peck
GENEVA, Feb. 27 -- Cases of multidrug-resistant tuberculosis have reached record levels worldwide and extensively drug-resistant tuberculosis (XDR-TB) has spread to 45 countries, according to the World Health Organization.
In its first major TB report in four years, the WHO estimated the global proportion of drug-resistant TB at 4.6%. China and India are estimated to account for 50% of the global burden of drug-resistant cases with the Russian Federation adding a further 7%.
The WHO findings were derived from data collected from 2002 through 2006 on 90,000 TB patients in 81 countries.
These survey data mark the first time that the global analysis included information about XDR-TB, but because few countries are currently equipped to diagnose this emerging disease, limited data were available for the report.
On the basis of the survey data, the WHO estimates there are nearly half a million new cases of MDR-TB a year, or about 5% of the nine million new TB cases of all types.
The highest rate was recorded in Baku, the capital of Azerbaijan, where nearly a quarter of all new TB cases were reported as multidrug-resistant.
Proportions of MDR-TB among new TB cases were 19.4% in Moldova, 16% in Donetsk in Ukraine, 15% in Tomsk Oblast in the Russian Federation, and 14.8% in Tashkent in Uzbekistan.
These rates surpass the highest levels of drug resistance published in the previous WHO report in 2004. Surveys in China also suggest that MDR-TB is widespread there.
But the true scale of the problem is unknown because few countries at risk have the needed surveillance programs, said Abigail Wright, M.P.H., a WHO TB expert who was the lead author of the report.
For example, only six countries in Africa -- the region with the highest occurrence rate of TB in the world -- were able to provide drug-resistance data. Other countries in the region could not conduct surveys because they lack the equipment and trained personnel needed to identify drug-resistant TB.
"Without these data, it is difficult to estimate the true burden and trends of MDR-TB and XDR-TB in the region," Wright said. "It is likely there are outbreaks of drug resistance going unnoticed and undetected."
The WHO also identified a link between HIV infection and MDR-TB in Latvia and Ukraine, where HIV-infected TB patients were twice as likely to have MDR-TB as patients who were not HIV-positive.
According to WHO, effective control of TB in low and middle-income countries would cost $4.8-billion in 2008, with $1-billion of that earmarked for MDR-TB and XDR-TB control. But the said current funding for TB control is $2.5-billion short of the needed amount.
Mario Raviglione, M.D., director of the WHO Stop TB Department, said fighting the growth of resistant TB strains requires "a frontal assault. If countries and the international community fail to address it aggressively now, we will lose this battle."