Clot-busting drug may work in Covid-19 emergency: Researchers
A repurposed clot-busting drug may work as an emergency measure for Covid-19 patients suffering from acute respiratory distress when ventilators are not available or not all that effective, according to researchers at the Massachusetts Institute of Technology (MIT) and the University of Colorado at Denver, Colorado.
The drug is the widely used protein called tissue plasminogen activator (tPA), which is administered to people who have suffered a cardiac arrest or stroke to dissolve blood clots.
Emerging data from China and Italy showed that Covid-19 patients have severe blood-clotting disorders that lead to respiratory failure and eventually death. Covid-19 patients suffer from inflammation-linked tissue damage, showed autopsy reports from China and Italy.
Past research also showed that blood clots often form in the lungs during respiratory failure, and tiny clots called microthrombi also form in the blood vessels of the lungs. These tiny clots prevent blood from reaching the airspaces of the lungs.
“If this were to work, which I hope it will, it could potentially be scaled up quickly, because every hospital already has it in their pharmacy. We don’t have to manufacture a new drug, and we don’t have to do the same kind of testing that you would have to do with a new agent,” said Michael Yaffe, a David H. Koch Professor of Science at MIT, who is the senior author of the study, which was published in the Journal of Trauma and Acute Care Surgery on Thursday.
While 81% of Covid-19 positive patients have mild disease, 5% of the patients need intensive care, including a ventillator to assist them to breathe as their lungs pack up.
Three hospitals in Massachusetts and Colorado in the United States of America are looking to test this therapy in critically ill Covid-19 patients.
India has an estimated 40,000 working ventilators for a population of around 1.4 billion people. Most ventillators are installed in government-run medical colleges and private hospitals located in metropolises and state capitals, but certainly will not be enough if there is a sudden spike in Covid-19 positive cases.
The blood-clotting drug, tPA, is available across India. “It is a natural protein found in the body and works by converting plasminogen to an enzyme called plasmin, which breaks down blot clots. It is very effective when administered between three and four and half hours into people who have suffered an acute ischemic stroke, provided they have no internal bleeding, including gastric haemorrhage,” said Dr. Pushpendra Renjen, senior consultant neurologist, Indraprastha Apollo Hospitals.
“The recommended dose for stroke is 0.9 mg/kg body weight, with 10% of it being injected and the rest given as an infusion over an hour. Depending on the patient’s weight, the drug costs between Rs 40,000 and Rs 50,000,” said Renjen.
The researchers plan to test tPA in patients under the US’s Food and Drug Administration’s “compassionate use” programme, which allows experimental drugs to be used in cases where there are no other treatment options.
The group plans to deliver the drug both intravenously or administer it directly into the airways. One dose will be given rapidly, say over a two-hour period, followed by an equivalent one given more slowly over 22 hours. Applied BioMath, a company spun out by former MIT researchers, is working on computational models to refine the dosage schedule.
“What we are hearing from our intensive care colleagues in Europe and in New York is that many of the critically ill patients with Covid-19 are hypercoagulable, meaning that they are clotting off their intravenous therapies, and having kidney and heart failure from blood clots, in addition to lung failure. There’s plenty of basic science to support the idea that this concept should be beneficial. The tricky part, of course, is figuring out the right dose and route of administration,” said Yaffe.
India has reported 649 Covid-19 positive cases and 13 deaths to date.