learn about COVID-19, its impact, and what you can do about it.
On account of COVID-19 being a novel virus, not enough evidence has been collected from clinical trials that would allow the recommendation of a specific antiviral treatment. Most treatments of COVID-19 consist of respiratory/intensive care. Scientists are currently conducting different clinical trials (controlled experiments testing the efficacy, side effects, dosage, and other important considerations) to find a safe and effective antiviral treatment. Many of these studies involve drugs that have shown in the past to treat other viruses in the betacoronavirus family such as SARS-Cov-1 and MERS-CoV (Middle East Respiratory Syndrome). Examples of these repurposed drugs include interferon beta-1b, lopinavir-ritonavir, and ribavirin.
Clinical trials typically go through five phases. In phase 0 of a clinical trial, scientists test drugs in small doses on a small group of patients to see if the drug will work as it is expected to. This phase is not always used but is low risk and can be useful to prevent costs if the drug does not work in future phases. In phase 1, scientists figure out if the drug is safe in humans, using a low dose on once again a small group of people. The goal is to determine the maximum dose that can be given while minimizing side effects. In phase 2 of a clinical trial, there are more participants and usually a higher dose. Scientists continue to observe for side effects that may not be as common as well as how well the treatment works. Should the drug seem safe and effective, it will proceed to phase 3. In phase 3, there are usually over a hundred patients in a clinical trial, and drugs are delivered over a longer period of time. They are even sometimes done around the world to have more diversity in patients. After phase 3 trials, drugs are usually submitted for FDA approval. Should the drug receive approval, they can become used in standard care and phase 4 trials usually commence. These trials are to watch for long term effects of the drug that take years to manifest, such as a patient’s quality of life after taking the drug.
Last week, a study was published in the journal, The Lancelet, regarding a phase 2 open-label randomized clinical trial. The trial tested a treatment including multiple drugs rather than a single drug because evidence from influenza patients indicated that a multi-drug treatment could be more effective in patients with a high viral load, meaning they have a high number of virus particles in their cell.1 This trial found that a combination of the three aforementioned drugs (interferon beta-1b, lopinavir-ritonavir, and ribavirin) could be successful in the treatment of moderate and mild cases of COVID-19.
Scientists surveyed 127 adult patients from six different public hospitals in Hong Kong who all tested positive for SARS-CoV-2 (the virus that causes COVID-19).2 Patients were randomly assigned to either receive the combination of drugs (the combination group) or just lopinavir-ritonavir (the control group) over a period of 14 days. Rather than being a double-blind trial (in which neither patients nor doctors know if a patient is receiving a placebo or the treatment), both researchers and patients knew which treatment the participant was receiving. While the trial being open-label could allow for bias, the report claims all patients were assigned randomly.
In addition to standard care, patients in the control group received a certain dosage of lopinavir and ritonavir every 12 hours. Along with the lopinavir-ritonavir treatment received by the control group, patients in the combination group received ribavirin every 12 hours and a certain dosage of interferon beta-1b (depending on how many days treatment began after patients began showing symptoms).3 Some adjustments (in frequency) to these treatments were made for patients displaying certain conditions, such as high levels of alanine transaminase, an enzyme whose presence could indicate possible liver damage.4 (Damaged cells in the liver will release the ALT enzyme to the bloodstream).
The study reports that the group receiving the combination of medicine had a “significantly shorter median time from start of study treatment to negative nasopharyngeal swab” of 7 days as opposed to the control group’s 12 days.5 One member of the control group discontinued treatment after one week because alanine transaminase was over six times ULN (upper limit of normal) but all other patients finished their treatment. Both groups displayed side effects of nausea (which required no interference) and diarrhea. One patient in the control group discontinued lopinavir–ritonavir because of biochemical hepatitis. No patients died during the study. Professor Kwok-Yung Yuen from the University of Hong Kong and a lead researcher said:
“Our trial demonstrates that early treatment of mild-to-moderate COVID-19 with a triple combination of antiviral drugs may rapidly suppress the amount of virus in a patient’s body, relieve symptoms, and reduce the risk to healthcare workers by reducing the duration and quantity of viral shedding (when the virus is detectable and potentially transmissible).”
While phase III clinical trials that include a larger patient sample to further confirm these findings are still required, the results from phase II are encouraging. Researchers on the team plan to investigate interferon beta-1b further; Dr. Jenny Lo, from Ruttonjee Hospital in Hong Kong, said: “Interferons are naturally occurring proteins, produced in response to viral infection, and the hope is that interferon beta-1b will boost the body’s ability to fight SARS-CoV-2.”7 With a world filled with anxiety and fear due to uncertainties surrounding this worldwide pandemic, this study provides hope to many that further phase III trials will confirm an effective and safe treatment.
Written by Jennifer Do-Dai
Authors and Editors