Anafranil

Drugs Hold Hope for Parkinson's, Obsessive-Compulsive Patients

Parkinson's disease patients and victims of a mental condition called obsessive-compulsive disorder will benefit from FDA's recent decisions to allow wider use of two promising but still experimental drugs for those conditions.

The drugs--clomipramine to treat severe cases of obsessive-compulsive disorder and selegiline to treat severe Parkinson's disease--were approved for broadened use in June. They are the fourth and fifth experimental therapies released under the agency's treatment investigational new drug (IND) regulations, which became effective in June 1987. The regulations allow promising experimental drugs to be provided to patients with immediately life-threatening or other serious conditions for which there is no other therapy, before complete data on the drug's safety and effectiveness are available.

Clomipramine--also known by its brand name Anafranil--was approved for wider use in treating obsessive-compulsive disorder June 7. As many as 5 million Americans suffer from obsessive-compulsive disorder, although only a small percentage are severely impaired by the condition. Those with the disorder cannot control their repetitive, ritualistic, compulsive behaviors (such as washing one's hands over and over and over again) or cannot suppress persistent, recurring, disturbing thoughts. In severe cases, preoccupation with these obsessive thoughts and compulsive rituals can keep the patient from functioning in work, school, and social and family relations--virtually every part of life.

Although some patients may respond to psychotherapy or behavior modification techniques, there are no approved drugs that are effective in curbing these obsessions and compulsions. But early trials of the experimental drug clomipramine provided promising results, so FDA is permitting its expanded use. Explained FDA Commissioner Frank E. Young, M.D., Ph.D.: "We will permit the drug's use in the most seriously afflicted. . . . But caution must be exercised because of a risk of seizures--which could lead to falls or accidents."

Those suffering from obsessive-compulsive disorder struggle with acute anxiety from their irrational thoughts and impulses. The patient sees these impulses as irrational and, often, even harmful. But to counteract the anxiety, the patient may engage in equally irrational repetitive acts that can be neither controlled nor suppressed.

In one case, a yound man was obsessed with the idea that he might push a stranger off a subway platform into th path of an oncoming train. He felt compelled to keep his arms rigidly at his sides. Other patients are compelled to take other irrational actions, such as repeatedly checking door locks.

In severe cases, the disorder prevents people from going outside or performing necessary tasks, such as turning on lights, performing repetitive work on an assembly line, or even preparing meals.

Clomipramine is not a cure, but recent clinical studies indicated that it can be effective in treating the symptoms of severe cases of obsessive-compulsive disorder. These studies, however, also indicated that use of the drug may significantly increase the risk of seizure. The rate of seizures in the studies was seven per thousand patients.

Strict standards have been set to ensure that patients are informed of the risks and are advised not to engage in any activity, such as operating heavy machinery, in which a sudden loss of consciousness would present a hazard to themselves or others.

On June 16, FDA approved wider use of selegiline to treat patients with severe Parkinson's disease who have not done well on standard forms of treatment.

Parkinson's disease is a serious degenerative disorder of the central nervous system that can affect people 40 and over. Patients suffer from a number of symptoms that include muscular rigidity, weak posture, and uncontrollable tremors of the hands, arms or legs. The disease is thought to result from reduced levels of dopamine, a brain chemical involved in body movement. Selegiline inhibits enzymes that inactivate dopamine.

Levodopa, the standard treatment for Parkinson's disease, supplements levels of dopamine. however, levodopa's effectiveness decreases over time, so the patient has to take greater amounts of the drug. These larger amounts produce serious side effects, including nausea, involuntary movements, and heart palpitations.

Selegiline is not a cure for Parkinson's disease, but recent clinical studies showed that symptoms were controlled in patients who received the drug along with low levels of levodopa.

"As many as 30,000 patients in the United States with severe Parkinson's disease may benefit from this combined treatment and be provided early access to a promising new therapy," said FDA Commissioner Young.

Selegiline has also been designated as an orphan drug by FDA's Office of Orphan Products Development. This status provides sponsors of drugs for rare diseases with tax and other financial incentives designed to encourage their development efforts.

For more about treatment INDs, see "Experimental Drugs for the Desperately Ill: A Progress Report" in the May 1988 FDA Consumer.

COPYRIGHT 1988 U.S. Government Printing Office
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