Covid-19: Lankans in quest for anti-viral drug
Crucial study by IBMBB scientists could point the way – 4 hits from around 3,500 FDA-approved compounds for other diseases
Astudy by scientists attached to the University of Colombo has pointed the way towards possible medications that could be used in the battle against the new coronavirus.
“Our study will go online today after which it will be picked up by a scientific journal,” Dr. Sameera R. Samarakoon of the Institute of Biochemistry, Molecular Biology & Biotechnology (IBMBB) of the University of Colombo told the Sunday Times.
Instead of trying out untested compounds, Dr. Samarakoon and team members Prof. Kamani Tennekoon and Dr. Kanishka Senathilake had decided to look at the tested compounds for diseases already approved by the Food and Drug Authority (FDA) of America.
“There are about 3,500 such compounds and we got four hits,” says Dr.
Samarakoon with excitement, hoping that Sri Lanka could work with countries such as China and America in taking it forward by initiating trials in a clinical setting.
In a different turn of events on Wednesday, at the National Institute of Infectious Diseases ( NIID), Angoda, it was time for smiles, hugs and selfies as the Chinese woman tourist who was the single ‘imported’ case of the new coronavirus in Sri Lanka left for China.
Greeted with a bouquet of flowers by Health Minister Pa vi th ra Wanniarachchi and top officials including the Director- General of Health Services, Dr. Anil Jasinghe, she placed a tray of flowers at the Budu Medura, before being discharged from the hospital. She communicated with those present through an App which acted as the translator.
NIID’s Consultant Physician Dr. Eranga Narangoda told the Sunday Times that he and his team looked after the Chinese patient from January 25 until February 19, when she left for home in China. (See box)
Off Thurstan Road, meanwhile, seated within the IBMBB building Dr. Samarakoon and his team were on a different track.
Dr. Samarakoon who is engaged in testing anti-cancer compounds was giving thought to adapting the set- up already in place for such testing, for the urgent need of fighting the disease – COVID-19.
Before detailing the study and the modus operandi of viruses, he points out how there is a rush to find a vaccine rather than testing compounds to produce anti- viral medication. This is because finding anti- viral medication is time- consuming and may yield results only in about 5-10 years.
So, what Dr. Samarakoon did was – without trying out new and untested compounds which would have to go through the rigorous processes of testing for toxicity etc – pick up the FDAapproved drugs which had already gone through stringent testing.
The testing before a new drug is introduced includes the initial step of using computer models. If it passes the first stage, then testing is done on cell cultures and animals in a pre-clinical drug trial. If it passes those as well, the drug would be used in human clinical trials. New drugs need to be tested and trialled for safety, effectiveness and dosage before they can be prescribed to patients.
Next, Dr. Samarakoon opens up the complex world of molecules and RNA ( ribonucleic acid) and explains that Chinese scientists had come up with the viral genome (RNA) of the new coronavirus.
The genome in the new coronavirus (named SARS-CoV-2) is a complete set of RNA which contains all the information needed to build and maintain it. In humans, a copy of the entire genome, more than 3 billion DNA base pairs, is contained in all cells that have a nucleus. While in humans, these cells can divide by themselves and grow, in viruses they cannot reproduce by themselves.
Dr. Samarakoon explains how a virus, when it enters ( infects) a susceptible human cell can direct that cell machinery to produce more viruses, each consisting of nucleic acid and an outer shell of protein.
Viral replication involves ‘attachment to a host cell, penetration, uncoating, replication, assembly and release’. During ‘attachment and penetration’, the virus attaches itself to a host cell and injects its genetic material into it; during ‘ uncoating, replication and assembly’, the viral RNA incorporates itself into the host cell’s genetic material and induces it to replicate the viral genome. During ‘ release’, the newly- created viruses are released to the other cells of the host.
Spotlighting what they did in the IBMBB laboratory, Dr. Samarakoon says how they made a ‘ model’ of the virus protein which is involved in causing the infection process in humans. Thereafter, they set about trying to block that activi
ty, using the FDA- approved compound list.
“We did the computational analysis and found that four can inhibit or bind with the protein to stop its infective process,” he said, adding that a few compounds have good affinity with the protein.
“Yes, we believe it is a breakthrough,” adds Dr. Samarakoon.