JULY 29 ― Before we make any rash decisions to approve any medications to treat or prevent a specific disease or symptom, there needs to be good evidence that using the medication will improve the outcome of the disease and will not cause more harm than good.
The same principle also applies when we want to repurpose a medication that has been approved for use for another disease, eg. a broad-spectrum anti-parasitic medication for viral infection. The drug will still need to go through stringent clinical trials.
We are mindful that currently many people are feeling helpless as the Covid-19 pandemic is raging and appears to spiral out of control, and everyone is looking for a miracle.
Let us stop and learn from history; the story of thalidomide.
Thalidomide was a drug developed in 1957, which was originally intended as a sedative or tranquiliser.
Based on findings from the early phases of its testing, the company that had developed the drug deemed that it was harmless to humans.
With that information in hand, the drug was allowed to be sold over-the-counter without a doctor's prescription. Later on, the drug was also repurposed for treating other symptoms and diseases, e.g., colds, flu, nausea and even morning sickness in pregnant women.
While thalidomide was initially thought to be safe for pregnancy, concerns regarding birth defects arose in the 1960s. Worldwide, more than 10,000 infants were reported to be affected and around 40 per cent died at the time of birth, whereas those who survived had serious limb deformities, as well as eye, urinary tract, or heart problems.
The thalidomide scandal had led governments and medical authorities around the world to ensure that any medication that is approved for human use should undergo stringent clinical trials and approval criteria.
The current evidence for the use of Ivermectin for both the prevention as well as treatment of Covid-19 are still inconclusive. The Cochrane Database of Systematic Review is the choice for trusted evidence for informed decisions for healthcare providers as they have very stringent criteria for conducting systematic reviews.
A recent systematic review and meta-analysis published by Cochrane showed a lack of evidence to support the use of ivermectin for treating or preventing Covid-19 due to limited number of studies and small number of participants.
The systematic review found 14 studies, which included 1,678 participants that investigated ivermectin compared to no treatment, placebo, or usual care. Only one study had investigated the use of ivermectin in preventing Covid-19.
Currently, there are another 31 ongoing studies, and 18 studies still requiring clarification from authors, or not yet published that will be able to provide more scientific evidence on both the effectiveness and safety of ivermectin.
Till then, we should wait for more concrete evidence before using ivermectin for Covid-19, as we do not want to fall into the thalidomide trap.
Aspirin, is another example of drug, which was once thought to be able to improve cognitive functions based on results from early phase studies including a small number of participants.
However, the findings of the ASPREE (ASPirin in Reducing Events in the Elderly) Study that involved 19,114 participants found that aspirin neither reduced the risk of developing Alzheimer’ Disease nor delayed milder losses of memory and thinking ability, as initially thought.
The bottom line is that we should not rush. We have taken the same cautious approach in the Covid-19 vaccination programme for pregnant women and children.
Let science lead the way, and prevent us from falling into the thalidomide trap.
* Dr Victor Hoe is a professor of occupational and public health, and Dr Nirmala Bhoo-Pathy is an associate professor of epidemiology and public health at the Faculty of Medicine, Universiti Malaya.