WEDNESDAY, Sept. 29 (HealthDayNews) -- A new drug is effective against potentially fatal fungal infections in cancer patients, researchers report.
These infections have emerged as a major problem for cancer patients who are being kept alive longer by aggressive treatment.
The need for new and better antifungal drugs is another indicator of success in the effort to make more cancers treatable and even curable, said Dr. Thomas J. Walsh, a senior investigator at the National Cancer Institute and lead author of a study on the new drug that appears in the Sept. 29 issue of the New England Journal of Medicine.
Chemotherapy and bone marrow transplants that are used to fight cancer weaken the body's defenses against infection, Walsh explained. Antibiotics can handle bacterial infections, but they aren't effective against fungi, he said. So fungal infections "have emerged in the last decade as particularly devastating complications" of cancer treatment, Walsh said.
The journal report describes a study comparing a drug called caspofungin, a member of a relatively new family of fungus-fighting medications, to an older drug, amphotericin B. The drugs were tested in more than 1,000 patients with persistent fever and low levels of infection-fighting blood cells that are indicators of fungal infections, Walsh said.
Caspofungin was at least as effective as the older drug against the fungal infections, with a virtually identical success rate just above 33 percent for both treatments, the study showed. But the incidence of adverse side effects was significantly lower for caspofungin. For example, only 2.6 percent of the patients who got that drug had kidney damage, compared to 11.5 percent of those given amphotericin B, Walsh said.
Those results allow a "new molecular strategy to hit these organisms," Walsh said. "Our approach is to try to treat earlier rather than later, a preventive strategy for patients at high risk."
Patients prone to fungal infections include most people with acute leukemia and those who develop persistent fever when they are treated with broad-spectrum antibiotics, he said.
The successful trial of caspofungin increases the number of drugs that can be used against fungal infections. It is the first member of a family of drugs called echinocandins to reach the market; at least two other compounds in the same family are under development. They are additions to the older family of antifungal agents called triazoles, Walsh said.
"Having these two groups of compounds gives us more versatility and more capability," he said.
Dr. Thomas F. Patterson, professor of medicine at the University of Texas Health Science Center at San Antonio, said if a fungal infection isn't treated successfully in cancer patients, "the outcome can be horrible, with mortality rates as high as 80 to 90 percent."
"We still are learning the best way to use these drugs," Patterson said. "Clinically, it is important to define which patients need treatment. You want to begin therapy before these infections really develop."
Patterson and his colleagues are working on ways to detect the earliest signs of a fungal infection. "If we could develop a test for early diagnosis, that could be really wonderful," he said.
More information
For more on infections and cancer patients, visit the American Cancer Society. |
