Medicine
The magic bullet for COVID-19? Dexamethasone (DEX) — the knowns and the unknowns
DEX reduces mortality in severe COVID-19 infection, no effect in mild and moderate cases
By Salman Hasan, PhD & Priyadarshi Ranjan, PhD
Doctors in UK recently announced that Dexamethasone (DEX), a cheap and widely available drug reduces mortality in COVID-19 patients that need oxygen or are on ventilators. In light of the recent debacles associated with a similarly promised drug — HCQ, it is imperative to learn more about DEX, especially since the clinical trial data is not yet peer-reviewed or published. Here are the three key points to know about DEX-
DEX reduces mortality in severe COVID-19 infection, no effect in mild and moderate cases
For the RECOVERY (Randomised Evaluation of COVID-19 Therapy) trial in UK, 2,104 patients were given 6mg of DEX (this is comparable to that given for allergic reactions) for 10 days. This group was compared to 4,321 patients that were not given any treatment. In the no treatment group, 41% of the patients on ventilators died while 25% of those requiring oxygen died. DEX significantly reduced mortality for these two groups by 33% and 20% respectively. It can be taken orally or intravenous in serious cases. It is important to note that DEX did not show any improvement in patients with mild COVID-19 not requiring oxygen or ventilator support. Lack of placebo-control can make it hard to evaluate any subjective outcomes measured on the patients. We still do not know about any possible side effects or the impact on the time to recovery.
DEX works by calming the immune system
Cortisone is a naturally released substance by our body in stress conditions like starvation or to calm down the immune system. It is also needed for fetal development during pregnancy. DEX is a synthetic, longer lasting, and more potent version of Cortisone. Due to its anti-inflammatory response it is often prescribed for Osteo and Rheumatoid Arthritis; it is also prescribed to calm the immune system in case allergic reactions, asthma or autoimmune disorders. Unlike, the possible anti-viral activity of Remdesivir and HCQ, DEX works by scaling down body’s immune reaction.
DEX is largely safe but questions remain
DEX is mostly safe in short term with manageable side effects like fluid retention causing swelling of feet and legs, high blood pressure, increase blood sugar levels, insomnia, gastric issues etc. Long term usage can cause osteoporosis, diabetes, hypertension, cataracts etc. In case of COVID-19, patients that are more likely to need oxygen or ventilator support tend to be elderly with co-morbidities like diabetes and cardiovascular issues. We still do not know how severe DEX’s side effects can be for this population.
With low cost and wide availability DEX can be a game changer in reducing mortality for the disease. However, it is unclear if DEX reduces the time to recovery in these patients. If it does not, then the impact on hospital patient burden would be minimal — since DEX does not prevent the likelihood of developing severe COVID-19 nor is it known if it reduces the time to recovery. Nevertheless, DEX’s perceived success in the clinical trial does kindles hope as number of COVID-19 patients continue in India as well as many other regions of the world.
