COVID-19 has created an unprecedented situation all over the world with no drug available to treat this virus. As a result, the need to find a cure has directed scientists and clinicians to drug repurposing, a process that involves finding a new use for an “old” drug. Drug repurposing is appealing as the safety, efficacy, and toxicity of an existing drug have been extensively studied by the US Food and Drug Administration and/or the European Medicines Agency. This is appealing during an emergency when time is ticking and large controlled trials, which take much time, are not suitable to address the existing situation. Some countries are against the use of drug repurposing because of the potential adverse effects associated with the drugs and the lack of statistically significant clinical data that can prove efficacy. Dr. Fatima Mraiche, Associate Professor of Pharmacology and Pathophysiology at the College of Pharmacy, QU Health, Qatar University, has been involved in research that looks at the new use of existing drugs and said, “Drug repurposing is a useful strategy of using existing therapeutics for new indications. Her current work investigates SGLT2 inhibitors, anti-diabetic agents, which show remarkable cardiovascular benefits and could be repurposed as novel cardio protective interventions in high-risk cardiovascular patients.”
Dr. Hazem Elewa, Associate Professor and Head of Clinical Training at the College of Pharmacy, QU Health, Qatar University said, “since supportive care is the mainstay treatment approach for COVID-19 patients, repurposing drugs approved for other indications to be used in the treatment of SARS-COV-2 is a smart, fast and practical idea. However, the health systems in the different countries have to assess the use of these repurposed drugs for safety and effectiveness in appropriately designed studies. Then, the repurposed drugs should be periodically reviewed based on the results of these studies to recommend those that work and avoid those that do not. If this is not done, you may end up using drugs that do not add any benefits or with harmful side effects. A good example is the use of hydroxychloroquine and azithromycin in COVID-19 patients. Preliminary results from a small study in France showed that this combination contributed to a reduction in time to a clinical resolution and a reduction in viral load. Since then, many other studies have shown a lack of efficacy or at most, very modest benefits from this combination. In addition, this combination is associated with cardiac toxicity. Currently, the CDC, WHO, and many international organizations recommend against its use, however, the combination is still recommended and prescribed by many practitioners which may be extremely harmful to patients.”
Furthermore, with the already increased economic burden of COVID-19 in societies, the cost of drug exploration is a major barrier for many. Here, within the context of cost, treating COVID-19 with repurposed drugs leads to significant cost savings since experiments related to general drug safety, pharmacokinetics, and the route of administration are already performed. It is important to emphasize, nonetheless, that cost savings cannot be what solely defines successful repurposing of drugs. A successful repurposing has to be confirmed via clinical studies that investigate the impact of several important factors that vary with the change in drug use, including the relevance of the disease, optimal dose, patients’ characteristics, and the drug interaction with other concurrent drugs in COVID-19 patients.
Dr. Daoud Al-Badriyeh, Associate Professor of Pharmacoeconomics at the College of Pharmacy, QU Health, Qatar University said, “while drug repurposing for COVID-19 treatment comes with added costs for evaluating the therapies and their safety via clinical studies in real-world settings of COVID-19 patients, this cost is easily surpassed by the cost-saving associated with not having to develop new drugs,” Dr. Daoud Al-Badriyeh clarified, however, that “potential cost saving with repurposed drugs may not be achieved, given that drug companies could potentially be inclined to support non-commercial efforts of repurposing. For example, based on a recent economic study published at the Journal of Virus Eradication, authors calculated that for one of the drugs, which reduced durations of COVID infections, the standard cost-effectiveness evaluations can justify a drug cost to hospitals that is as high as $4,500, assuming a case of life saved as an outcome. This is when, based on how much this drug really costs to manufacture, having the drug costing hospitals only $10 for 10 days of use will also have the company recovering its manufacturing cost. Indeed, there have been reports of drug companies increasing the pricing of existing drugs for use in COVID-19 management, which often led to a backlash on social media. Unless pharmaceutical companies pledge to make drugs accessible and affordable to governments and patients around the world, therefore, an economic benefit of repurposing may never be attained.”
Many drugs have been suggested for repurposing to treat COVID-19 patients including remdesivir, camostat, and nafamostat. The key point with any of these potential treatments is to rely on scientific evidence to ensure that the repurposed drugs are safe and effective, and to enable collaboration among institutions to achieve access and affordability.
Source: Qatar University