Tablets that were supposed to make pregnancy easier achieved notoriety by causing birth defects. Séamus Lennondescribes the legacy of thalidomide
Fifty years ago, on October 1st, 1957, a medicine known as Contergan was marketed as a sedative and anti-nausea drug in West Germany and later on in a total of 46 countries, including Ireland.
However, within four years it was withdrawn from the market as evidence mounted that the drug was responsible for an epidemic of malformations of the limbs and internal organs in newborn babies.
The drug was more commonly known as thalidomide and in total was responsible for the birth of up to 12,000 malformed babies, with only about 5,000 of these infants surviving past childhood.
The manufacturer - a small company called Grunenthal had discovered that the drug was extremely safe in animals, and thus launched a massive marketing campaign in October 1957, claiming that this new drug was a better sedative than anything else on the market, and furthermore that it was completely safe.
The marketing campaign was very successful, and by 1961 it was the best-selling sedative in Germany, and at one stage approximately one in three adults were taking the drug to help them sleep.
However, doctors became concerned with the increase in the rate of births of infants with malformations, and a paediatrician - Prof Widukind Lenz - interviewed mothers of such babies and quickly deduced that the one thing all such mothers had in common was that they took thalidomide early during their pregnancy. He warned the company and the drug was withdrawn from the market.
The story of thalidomide took another strange twist in 1964 when a doctor in Jerusalem was presented with a leprosy patient who had developed serious complications from the disease.
The doctor - Dr Sheskin - had tried most of the conventional approaches to no avail, when he stumbled across an old bottle of thalidomide tablets and decided to use these as a last resort.
The results were dramatic - the patient who had literally not slept for weeks due to severe pain slept soundly that night and his sores began to heal.
This was the start of the renewal of scientific interest in the drug and because of this discovery, thalidomide has been used in countries where leprosy is prevalent since 1965, and still remains the drug of choice in treating certain complications of this disease.
The drug was manufactured in South America over the years to supply local doctors who were treating leprosy patients.
In the early 1980s Aids patients in the US began illegally importing thalidomide from South America as they found that it also relieved some of the symptoms of that disease.
Various companies then started to do new trials with the drug, and in 1998 thalidomide was approved by the US Food and Drug Administration for the treatment of leprosy.
However, the FDA knew that most uses of the drug would be for HIV patients, and at last a pure form of the drug was available to such patients. Doctors prescribing thalidomide in the US must ensure that patients are taken through an education programme on the dangers of the drug.
Also, female patients must have passed a pregnancy test before they are prescribed thalidomide, and must practise two forms of birth control while taking the drug.
Since its revival as a medicine, thalidomide has been used to treat over 130 different conditions, and is now used to treat certain cancers - with best results in patients suffering multiple myelomas.
The reason that thalidomide caused defects in the developing foetus was because it interfered with the creation of new blood vessels in the foetus and it is this same property that makes it a useful drug in treating certain cancers - it prevents some tumours from spreading by interfering with the development of new blood vessels that tumours depend on for their growth.
Without doubt, thalidomide represents one of the worst medical tragedies that the world has witnessed, and is a pertinent reminder of the dangers associated with new drug development.
There is no one simple answer as to why the tragedy occurred but at the time, pharmaceutical companies did not have to complete rigorous safety trials prior to marketing a new medicine.
Also, the company involved had a slipshod attitude to the quality of what little research they did and ignored warnings from doctors when side effects were first noticed in adults.
One good consequence of this sorry story was that many countries quickly reformed the laws and regulations governing the development, manufacture and marketing of new medicines.
Fifty years on, many of the victims of thalidomide are still leading successful lives.
Indeed, the ability of the victims of the drug to surmount the obstacles that they faced reflects the ability of the human spirit to overcome adversity.
Dr Séamus Lennon is head of the department of Life and Physical sciences at the Galway Mayo Institute of Technology