South African medical scientists have recently hailed thalidomide as a possible “wonder drug” in treating children with TB meningitis. This is an infection of the tissues covering the brain and spinal cord which people who are HIV-positive or have a weakened immune system or drink alcohol in excess are more susceptible to.
A major redemption
Today many people are unaware that thalidomide has been at the centre of controversy for a long time. It was banned in the early 1960s after it caused the worst drug disaster in history when thousands of babies were born with a range of defects.
Thalidomide was produced to treat morning sickness. But this was only one of its uses. It was also marketed as a sedative, an anti-fungal, for influenza, and for dysentery. The mechanisms of its action are still not fully understood.
If the current South African clinical trials are indeed a medical breakthrough, this will be a major redemption for a drug which has previously proved disastrous or less effective than safer treatments. The turnaround will also come at a time when the need to improve and expand TB treatments and Aids remains urgent, and when the incidence of cancers is significantly on the rise.
In the wake of these developments, informed discussion by medical scientists, pharmaceutical producers, policymakers, social scientists and civil society of the promises and the perils of this “flamboyantly teratogenic” drug is needed.
In the drug’s “first wave”, thalidomide was first produced from the mid-1950s by the German pharmaceutical giant, Chemie-Grünenthal GmbH.
In hundreds of adults across the globe, thalidomide caused irreversible peripheral neuritis or damage to the nerves. Most infamously, it caused a range of severe congenital defects, most typically undeveloped limbs, eyes and ears. At the lowest estimate, 10,000 thalidomide-damaged children were born and thousands of women miscarried or aborted.
Thalidomide was withdrawn from the market in the early 1960s and could only be used for specially approved experiments.
By the mid-1960s, medical researchers were experimenting with thalidomide in several medical settings. In Israel it was used to treat ENL, a complication of leprosy or Hansen’s disease. The World Health Organisation then approved a number of test sites in India, Spain, and two in Africa – Mali and Somalia.
In 1975, the US’s Food and Drug Administration gave limited permission for thalidomide’s use in leprosy.
But, by the early 1980s, the World Health Organisation withdrew its endorsement.
Despite this, thalidomide remained the preferred treatment for leprosy in several South American countries, most notably Brazil. And its reputation as a potent cure for leprosy created new “communities of consumers”. The drug has been manufactured in Brazil since the 1980s.
There are still mothers taking the drug unwittingly, accidentally, or illicitly. This results in children being born with underdeveloped or absent limbs.
In the 1990s, drug “buyer’s clubs” in the US smuggled thalidomide into the country as one of a host of hoped-for alternative treatments for HIV. The Federal Drug Administration (FDA) then agreed to allow the legal use of thalidomide, albeit under stringent conditions.
An African context
In the late 1950s and early 1960s, thalidomide was exported to more than a dozen African countries. Exports of Entero-Sediv, a thalidomide-containing preparation for use in intestinal infections and other related conditions, were among Grünenthal’s leading thalidomide products to 1961.
Thalidomide-damaged babies were born but the actual number is not known. It is widely believed that thalidomide was not available in South Africa in the 1950s and 1960s. There are no officially acknowledged thalidomide-affected people born in South Africa.
But recent research shows that small quantities of thalidomide-containing products were imported into South Africa by a German general dealer in Port Elizabeth, a seaside town along the east coast of the country.
South Africa has another link to the drug. The development of thalidomide and its analogues – most notably lenalomide and pomalidomid – have since been licensed by Celgene Corporation.
The corporation has worked closely with professor Gilla Kaplan, who does extensive research into leprosy and TB. She has research and professional links with researchers at the universities of Cape Town, Kwa-Zulu Natal and Witwatersrand.
Celgene is acutely aware of the teratogenic properties of its thalidomide-related products and has a stated a vigorous commitment to patient safety. In 2000, the company was fined by the FDA for off-label uses of thalidomide.
Since the FDA caution, its products Revlimid and lenalomide have been approved in the US to treat cancers such as multiple myeloma and diseases that affect blood cell production in the bone marrow known as myelodysplastic syndromes.
Revlimid is considered a blockbuster blood-cancer drug. It will be tested in trials for treatment of a kind of lymphoma.
Avoiding the same mistakes
If thalidomide is in fact medically effective, the question to ask is: can its administration be responsibly controlled?
The South American experience shows that regulating its use may not be easily achieved, or even possible. For instance, thalidomide can easily be bought online.
To avoid a repeat of the past, at least three measures must be put in place.
- The first is to understand what challenges there are in relation to the drug in Africa, and to consider how they can be addressed.
- The second is to ensure pharmacovigilance structures on the continent are equipped to respond to reports of any negative side-effects.- The third is for governments and health bodies to understand who the “communities of consumption” are that might be receptive to off-label or illicit uses of thalidomide – and how they can be averted.
This article was originally published on The Conversation. Read the original article.
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