Thalidomide

It seemed like an innocuous enough drug. Thalidomide was so safe, its makers said, Canadian health regulators agreed that it could be sold without prescription.

The drug helped people sleep and took care of symptoms of morning sickness for pregnant women.

It was developed by the German pharmaceutical company Grunenthal and hit the market in October 1957. Two years later, it was approved for use in Canada. The United States held off — the Food and Drug Administration demanded more data on the drug's safety before it would agree to approve it.

As the FDA waited for the results of studies into thalidomide, reports began surfacing in Europe of unusual side effects experienced by people taking the drug. Among them was peripheral neuropathy, or damage to the nervous system that serves limbs and organs. This can lead to pain, numbness and gait imbalance.

There were also more disturbing side effects reported. Women were giving birth to babies with severe defects like abnormally short limbs, flipper-like arms and toes growing out of the hips.

It's estimated that as many as 12,000 babies were born with deformities linked to thalidomide. By August 1962, at least 42 were born in Canada. A task force established by the federal government later pegged the number of Canadian children born with thalidomide-induced deformities at 115.

The German government ordered thalidomide off the market by the end of November 1961, against the wishes of Grunenthal. But the drug remained available in Canada until March 1962.

There were numerous lawsuits and settlements worldwide in the years after thalidomide was pulled. In 1970, a case was settled in Germany with Grunenthal for $31 million US plus an estimated $13.5 million to $27 million US from the German government.

In Canada, U.S.-based Richardson-Merrell Inc. distributed the drug, and each family reached undisclosed individual settlements. In 1990, the federal government extended assistance of $7.5 million to the Canadian-born "thalidomiders."

While the drug was officially off the market, it was never totally gone. In 1964, an Israeli doctor found that thalidomide helped ease erythema nodosum leprosum (ENL), a very painful complication of leprosy. Thalidomide is effective at relieving the pain of ENL because it limits the immune system's response to leprosy bacilli in the body.

The body responds by trying to attack the bacilli, which causes burning red nodules to break out on the skin. Thalidomide acts as a powerful anti-inflammatory, reducing the body's production of a protein that stimulates inflammation within the body.

In 1998, the FDA approved an application by the maker of thalidomide — Celgene Corp. — to market the drug under the name of thalomid for the treatment of ENL.

The drug was also found to be effective at treating cachexia — severe weight loss experienced by people dealing with diseases such as AIDS, TB and leprosy. The weight loss is believed to be triggered by tumour necrosis factor, the same protein that stimulates inflammation within the body.

Thalidomide was also found to be helpful for AIDS patients suffering from painful lesions in the mouth and throat, which affects their ability to eat. In 1994, the FDA formed a Thalidomide Working Group to monitor use of the drug. The agency also imposed severe restrictions on the distribution of thalomid — the current name the drug goes by — through the System for Thalidomide Education and Prescribing Safety (STEPS) program.

Thalidomide is also being looked at as a treatment for several other diseases including prostate cancer, lymphoma, and Crohn's disease.

In May 2006, the FDA approved thalidomide in combination with dexamethasone for the treatment of patients with multiple myeloma, a type of bone marrow cancer. Patients with the disease don't generally live long after diagnosis. But studies have suggested that while taking thalidomide in combination with dexamethasone won't cure multiple myeloma, patients could live longer than those being treated with other drug combinations.

The latest study was published in the Nov. 22, 2007, edition of the New England Journal of Medicine, nine years after a much smaller study by Arkansas researchers found that thalidomide showed promise as a treatment for multiple myeloma.

Celgene's website includes a long list of thalidomide's side effects, including:

• Severe, life-threatening human birth defects.
• Deep-vein thrombosis.
• Drowsiness, dizziness, and seizures.
• Constipation.

Thalidomide has not been licensed for use in Canada — and the Thalidomide Victims Association of Canada wants to keep it that way. The association represents thalidomide victims and their relatives.

The association says it will never accept a world with thalidomide in it. Its position on the use of thalidomide to treat diseases like leprosy and multiple myeloma is to take no position.

However, the association says on its website that it is "very concerned that thalidomide appears to be becoming a drug of first choice again instead of the drug of last resort thalidomide victims believe it should be."