CDC suspends study aftger patients become resistant to drug

ATLANTA - The Centers for Disease Control and Prevention has suspended a drug trial for patients who have both tuberculosis and advanced HIV after five patients developed resistance to the drug. <br> <br> The drug, rifabutin, was being given twice weekly to 159 patients with HIV and TB. Rifabutin is considered safe in combination with protease inhibitors, a key type of AIDS drug. <br> <br> But the drug failed for five of the patients. All of them had apparently built resistance to rifabutin after taking similar drugs twice weekly in earlier stages of their TB infections. <br> <br> The drug trial began about two years ago and was suspended March sixth. <br> <br> The chief of TB elimination at the CDC, Doctor Kenneth Castro, said the agency decided to be on the safe side to avoid the risk. <br> <br> The five patients also had extremely low counts of CD-4 cells, which kill invading organisms and boost the immune system. <br> <br> The CDC said all five patients are responding well to other treatment. But the alternative regimen likely will take 12 to 18 months, compared to six to nine months with rifampin.