Clinical Trials Day – 20 May 2021

Article category: News .
May 19, 2021


How did an 18th century British naval doctor help us beat the Corona Virus?

Retina South Africa would like to pay tribute to the thousands of dedicated clinical researchers who work so hard to bring treatments and new therapies to patients worldwide in every area of health and disease.

The Covid-19 Pandemic has brought Clinical Trials into sharp focus.

If not for the years of research into vaccines and the mRNA type of vaccine in particular, the world would have been powerless to try and control this novel virus.

So, what are clinical trials and why are they necessary?
A clinical trial is a controlled test to see if a medical intervention of any substance or drug is both safe and effective. Undertested interventions can lead to disasters such as the disastrous limb malformations in infants whose pregnant mothers were prescribed Thalidomide for morning sickness. In addition, the multiple dangers of long-term use of Opioids that lead to severe addiction were also not properly tested and millions of patients now continue to be addicted to these strong pain killers.

Clinical Trials are conducted in 3 phases with increasing numbers of patients and sometimes different dosage levels. Phase 1 trials are usually done on a small number of patients to determine safety and these safety outcomes will govern whether the trial can move onto Phase 2 – where a larger number of people are enrolled. Phase 3 trials include dozens or even hundreds of patients who are given the drug or a placebo. Placebos are “fake” harmless treatments that are included in the trial to give comparison results. Clinical Trials are strictly controlled by Government agencies such as the Department of Health in South Africa or the well know Federal Drug Agency [ FDA] in America.

Due to the emphasis on safety and the need to prove efficacy clinical trials may take up to 10 years to complete. The Covid-19 trials were fast tracked at “Warp Speed” to bring vaccines to the market at a dizzying rate.

Some of the minor “Adverse Effects“ that are now being discovered would previously have been identified in trials that follow years of study.

With Covid-19 time was a luxury that the world did not have and fortunately the adverse events are treatable and not life-threatening.

How did Clinical Trials evolve?
The first recorded “test” on selected people was by a doctor in the British navy- James Lind. He developed the theory that citrus fruits could cure scurvy; a dreaded disease that is now known to be caused by a vitamin C deficiency. In Lind’s day, the concept of vitamins was unknown, but Scurvy was a killer. Scurvy caused more deaths in the British fleets in the 17th and 18th century than French and Spanish armies combined. In 1747 Lind tested the effect of various interventions on groups of sailors. One group was given a quart of Cider daily, a second group received 25 drops of Sulphuric acid while a third group had six spoonful’s of vinegar. A fourth group drank sea water, while the fifth group were given a spicy paste and barley water. The final and most important group received two oranges and one lemon daily. The trial only lasted a few days as they ran out of the citrus fruit but the results were overwhelming, for, as we now know Vitamin C is necessary for the maintenance of healthy connective tissue throughout the human body. Lind’s meticulous records and observations formed the basis of controlled testing that we use today.

In Retinal research clinical trials have led to the first ever registered gene therapy to treat a genetic form of retinal blindness. The treatment is to replace a faulty section of DNA that causes severe vision loss in young children.

Clinical trials to test many other gene-specific and more generic forms of intervention are under way but at the traditional slower rate.

Claudette Medefindt, Head of Science at Retina South Africa stated that

“Over 25 000 South Africans lose their vision due to genetic forms of retinal blindness. Research drives clinical trials and money funds research.

We have thousands of young people from needy families who may be eligible for clinical trials or imminent gene specific treatments, but they cannot afford genetic testing that the Government does not provide. We appeal to sponsors to help us fund these tests privately” Medefindt said.

Retina South Africa together with the Division of Human Genetics at the University of Cape Town and the Pretoria Eye Institute have successfully recruited patients for an on-going clinical trial in South Africa to treat Stargardt Disease, a genetic condition that robs young people of their precious central vision, making them unable to read, write, drive or watch TV or digital screens.

Retina South Africa needs all families with a retinal disease to register. Please complete the “Become A Member Form”, under the Get Involved tab on our website, We will then send you the relevant documentation.

More Articles