New TB Treatment Approved by FDA
The Food and Drug Administration on Tuesday approved the first new drug for treatment of pulmonary tuberculosis in 25 years, a development described by some doctors as a potential major stride against the deadly scourge.
Rifapentine, which is marketed under the name Priftin, requires fewer doses than the cumbersome number needed in current therapies, making it more likely that patients would complete the treatment, the FDA said. The drug will be sold by Hoechst Marion Roussel Inc., the U.S. pharmaceuticals unit of Germany’s Hoechst.
The United States, which had 19,000 new cases of pulmonary tuberculosis last year, is the first country to approve Priftin.
Worldwide, tuberculosis is the most frequent killer among infectious diseases. The World Health Organization estimates there will be 90 million new cases of tuberculosis and 30 million deaths in the 1990s.
Priftin is similar to and about as effective as an older tuberculosis drug currently sold by Hoechst, rifampin, which must also be used in combination with other anti-tuberculosis agents.
Current treatments require daily doses of rifampin for two months in combination with three other generic drugs, isoniazid, pyrazinamide and ethambutol, followed by four months of treatment at least twice a week. Priftin requires only weekly instead of multiple weekly doses in the second stage of therapy.
Patient failure to complete the long treatment has been a major problem in combating tuberculosis, and has also lead to serious concerns about its growing resistance to drugs.
Clinical studies, mainly in South Africa, showed Priftin to be comparable to standard therapies, but with relapse rates of 10% instead of 5% with rifampin.
Alex Zisson, a Hambrecht & Quist analyst, said Hoechst would derive little income from the new drug. “It’s sort of pro bono work drug companies sometimes do,” he said.
Zisson said tuberculosis cases in the United States are most common among immigrants, people with the HIV virus whose immune systems make them more susceptible to infectious diseases, and prisoners.