Interferon Effective in Treating MS, Hepatitis
Thirty years ago, interferon was hailed as a miracle drug, a naturally occurring chemical that could fight off all kinds of viruses. In study after study, however, researchers found that the drug could not match its potential, and its use was limited to isolated niches.
Two new studies on multiple sclerosis and hepatitis C infections released in the past week bring some of the luster back to the drug. They show conclusively that interferon is an effective treatment in both conditions.
In the largest MS study ever, and the only one to attempt treating patients at high risk of disease progression, a multicountry team found that interferon significantly reduced the number of relapses suffered by patients and prolonged the interval between relapses.
The benefit was greatest in patients at highest risk of disease progression and who received unusually high doses of the drug, the team reported in Saturday’s Lancet. “The results . . . show that interferon-beta influences the course of the disease and not just the symptoms, and demonstrate that with high dose, disease progression can be slowed in patients at high risk of becoming more disabled,” said Dr. Mark Freedman of the Ottawa Hospital in Ontario, Canada.
The study enrolled 560 patients who received either a placebo or one of two doses of genetically engineered interferon beta-1a. The drug reduced the number of relapses per patient by 32.4% in the high-dose group and by 28.9% in the low-dose group.
Among the patients at highest risk of progression, however, only 27% of those receiving the high dose showed disease progression, compared to 56% of those receiving placebo. The high dose also tripled the time to progression in this group to 21.3 months, compared to 7.3 months among those who received placebo.
Interferon is also used to treat chronic hepatitis C infections, but its effectiveness is limited because it is cleared from the body rapidly. New results presented Sunday at the American Assn. for Liver Diseases meeting in Chicago indicate that its efficacy can be dramatically increased by attaching it to polymers that keep it in the body for as long as a week.
In a new drug called pegylated interferon, the drug is attached to inert, hairlike strands of a polymer called polyethylene glycol.
In a study of 155 patients, Dr. Michael Freed of the University of North Carolina at Chapel Hill reported that pegylated interferon reduced hepatitis C viral levels below the limits of detection in 36% of those patients treated once a week with the drug. In contrast, that level was reached in only 3% of patients treated three times per week with conventional interferon.
Hoffman-La Roche, which manufactures pegylated interferon, hopes to have it commercially available within a year.
A Medical Reason for Forgetfulness
President Clinton may have had a biological reason for not remembering alleged sex acts with Monica Lewinsky: sexually induced amnesia, say two researchers from Johns Hopkins University. They say that the physical process of “bearing down,” as people do when they move their bowels, deliver a baby or have sexual intercourse, can produce six to 12 hours of global amnesia in which new memories cannot be formed. Bearing down is known medically as a Valsalva maneuver.
Drs. Chi Van Dang and Lawrence B. Gardner of Hopkins report in Saturday’s Lancet on two men, ages 72 and 75, who were brought to the emergency rooms by their wives a half-hour or so after sex when the men became seriously confused; they remained fully conscious. One man thought he had suffered a stroke.
In a Valsalva maneuver, intense pressure in the blood vessels of the brain results in temporary lack of blood flow to the central part of the brain, producing amnesia. The same effect may reduce bad memories of childbirth.
“As with our patients, who could not remember the name of the current U.S. president, a presidential Valsalva maneuver during each of his recent escapades may have legally allowed him not to recall specific events and may thereby help maintain international stability during the current transient global economic fluctuation,” Dang said.
Shark Cartilage Called Useless Against Cancer
Shark cartilage, widely touted as a cure for cancer, is virtually worthless, according to a new study in the November Journal of Clinical Oncology. Physicians estimate that at least 50,000 Americans have tried shark cartilage for the treatment of cancer, but researchers have been skeptical because shark cartilage pills are destroyed in the stomach and don’t reach the tumors.
Dr. Denis R. Miller and his colleagues at the Cancer Treatment Research Foundation in Arlington Heights, Ill., gave the pills to 60 patients with terminal cancer of the brain, breast, colon, prostate, bladder or lymph system. They concluded that the product did nothing to prolong life or improve quality of life.
“It doesn’t work,” Miller said.
Fetal Nourishment May Affect Obesity
Obesity in children and adults may start when babies are undernourished in the womb and then overfed to catch up, researchers say in a study in the November issue of Pediatrics. Researchers from the National Institute of Child Health and Human Development found that underweight newborns began life with less muscle than other babies but soon had more fat relative to their size.
The discovery could lead to new ways to prevent obesity and the chronic illnesses it is linked to later in life, including diabetes and heart disease, said the study’s lead author, Mary L. Hediger.
The study involved 4,400 U.S. children nationwide, ages 2 months to 47 months, who were measured from 1988 through 1994. About 9% of the children were small for their gestational age, or time spent in the womb.
“The children who were small for [gestational] age had less muscle than average, but as young as 2 months they had levels of fat that were similar to the larger children,” Hediger said. “What we think is going on here is that the fetuses who were undernourished . . . adapt to these low levels of nutrients that they’re receiving from the mother so that their growth slows, and they’re small at birth.” To keep underweight infants from becoming obese adults, doctors and parents may need to tailor nutrition and exercise to the baby’s needs from day one, Hediger said.
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The Associated Press contributed to this article.
