Wider Access to Alzheimer’s Drug Urged : Health: Tacrine or THA has shown mixed results. Even so, FDA panel favors expanded use if carefully controlled studies are conducted simultaneously.
Despite some reservations, a federal advisory panel Monday recommended that the first experimental drug to treat Alzheimer’s disease be made more widely available while it is still being studied.
The drug, Tacrine or THA, manufactured by Warner-Lambert Co., is a controversial therapy that thus far has shown mixed results in clinical trials. It is not a cure for the progressive and ultimately fatal disease but has helped some Alzheimer’s patients improve their ability to think and function, according to the company. The drug, however, has also been shown to cause liver damage in some patients.
The Food and Drug Administration’s peripheral and central nervous system drugs advisory committee emphasized that studies to date “were an insufficient demonstration of clinical effectiveness” of the drug.
Nevertheless, an informal vote taken at the conclusion of the meeting showed that most of its members favored an “expanded access” program--but only if carefully controlled clinical studies are conducted simultaneously to determine whether the drug is effective, particularly at higher doses than have thus far been studied. In this case, a controlled study would compare patients taking THA to those taking a medically worthless placebo.
Alzheimer’s disease causes a gradual deterioration of mental processes, including memory. It is the fourth-leading cause of death among adult Americans, killing 100,000 a year. The illness afflicts about 4 million people in the United States, striking more than 10% of the population over 65 and nearly 50% of those 85 or older.
Eventually, Alzheimer’s patients cannot care for themselves and require constant supervision. Over the course of the disease--which can take years--the process often reaps an enormous emotional and financial toll on the victim’s families and friends. The Alzheimer’s Assn., a national voluntary organization, estimates the annual cost of caring for the nation’s Alzheimer’s patients at $80 billion to $90 billion.
The FDA allows expanded access to experimental drugs that are promising but unproved in cases of serious illnesses where there are few or no treatment alternatives otherwise available.
Advisory committee recommendations are not binding on the FDA but generally wield considerable weight in agency decision making.
The company has proposed an expanded access program that would make the drug available to as many as 50,000 patients nationwide who suffer from mild to moderate Alzheimer’s. If approved, it would be one of the largest--if not the largest--such program ever undertaken. Data obtained from the expanded access of THA would be used only to study the drug’s safety, not whether it is effective in treating the disease.
The FDA already appears favorably disposed to such a program. Last spring--after the advisory committee refused to recommend that the drug be approved for marketing--the agency suggested that the company design an expanded access program so that the drug’s safety could be further studied.
In fact, the FDA’s new commissioner, Dr. David A. Kessler, told the committee that he believes Alzheimer’s therapies “deserve the same focused energy and high priority attention we now devote to drugs for AIDS and cancer.”
In recent years, the FDA has made AIDS and cancer drugs a high priority and has shown an increased willingness to release promising experimental therapies for widespread use before they have been thoroughly studied.
“Death may not come as swiftly to Alzheimer’s patients as to people with AIDS, but it is just as destructive to their quality of life,” Kessler said. “And it needs to be treated with the same urgency.”
George D. Rehnquist, a Knoxville, Tenn., man whose wife was one of the first Alzheimer’s patients to use the drug, called the results “miraculous” and urged the committee to recommend an expanded access program.
“When a patient has a death sentence, what has he or she got to lose? Nothing,” he said.
Dr. Willis Maddrey, vice president for clinical affairs at the University of Texas Southwestern Medical Center in Dallas, told the panel that he knows of no deaths associated with liver damage caused by the drug and that “the chances of anyone dying or being irreparably hurt by this drug are minimal.”
Warner Lambert has said that clinical trials of the drug, which would be marketed as Cognex, had demonstrated clear improvement in Alzheimer’s patients, although other scientists have disputed those results.
