How far are we from COVID-19 drugs, vaccine?
Scientists around the world are looking for a vaccine and drugs to combat the novel coronavirus. What are these various approaches and the signals so far?
As the world cocoons itself against the novel coronavirus, scientists are at work around the world for development of vaccines and therapeutics.
How soon can a drug or a vaccine be expected?
We are still months away from a vaccine. In a recent interview to The Indian Express, WHO chief scientist Dr Soumya Swaminathan said: “if everything goes really well, we would probably have a vaccine in the next 12-18 months but even after that there would be the question of availability of sufficient doses. We are probably looking at an 18-24 month window for that.”
Drug and vaccine development is an elaborate process. Zeroing in on a candidate drug or vaccine may take years. Once a new drug has passed testing in animals, clinical trials kick in. Over three phases, its safety and efficacy have to be tested as per protocols. A fourth stage involves collection and analysis of post-marketing data.
However, the novel coronavirus is from a family on which work is already being done worldwide after SARS and MERS. “A lot of existing vaccine development efforts can be modified a little bit so we are not exactly starting from scratch… However on the vaccines it may be at least six months before the first data starts coming in – there is always a probability that it will not be a success also. On the treatment side, there may be some news about the ritonavir-lopinavir combination (both are anti-HIV drugs) any time now. The idea is to wait for the data on efficacy of existing antivirals and see how much better we make them,” said Dr Anurag Agarwal, director, CSIR Institute of Genomics and Integrative Biology.
The World Health Organization (WHO) has announced SOLIDARITY, a multi-arm, multi-country clinical trial to look for the best treatment against COVID-19. It will test the antiviral drug remdesivir; a combination of HIV drugs lopinavir and ritonavir; lopinavir and ritonavir plus interferon beta; and the antimalarial drug chloroquine. So far Argentina, Bahrain, Canada, France, Iran, Norway, South Africa, Spain, Switzerland, and Thailand have signed up.
REMDESIVIR: According to Dr Swaminathan, the most promising trial is the one on remdesivir under the aegis of the US National Institutes of Health (NIH). Trials have begun on adult patients with COVID-19 hospitalised at the University of Nebraska Medical Center. “The first trial participant is an American who was repatriated after being quarantined on the Diamond Princess cruise ship that docked in Yokohama, Japan and volunteered to participate in the study,” the NIH said. Remdesivir, developed by Gilead Sciences Inc, was previously tested in humans with Ebola virus disease and has also shown promise against MERS and SARS.
LOPINAVIR + RITONAVIR: India has had its own experience with a combination of these second-line HIV drugs — 12 people recovered without antivirals (one later died; this is not being officially counted as a COVID-19 death). Around the world, trials are under way. In a paper in the New England Journal of Medicine, Chinese researchers reported a mortality of 22% in severely ill patients who had been administered the lopinavir-ritonavir combination, higher than the 11% to 14.5% mortality reported in initial descriptive studies. The researchers concluded: “No benefit was observed with lopinavir–ritonavir treatment beyond standard care.”
CHLOROQUINE: In a paper pending peer review, researchers from China’s Sun Yat-sen University reported an ongoing study using the lopinavir-ritonavir combination along with chloroquine. The drugs are being administered to eligible patients between February 12 and May 31. “Earlier studies have shown that chloroquine can inhibit coronavirus replication through multiple mechanisms. Our previous use of chloroquine to treat patients with SARS-CoV-2 (novel coronavirus)-infected pneumonia has a higher negative rate of nucleic acid in throat swabs within 5 days after administration than that using lopinavir/ritonavir,” the researchers said.
FAVIPIRAVI: This is a drug used in Japan to treat new strains of influenza. Media quoted China’s science and technology authorities as saying the drug, developed by a subsidiary of Fujifilm, appeared to be effective in coronavirus patients. Patients given the medicine were reported to have turned negative after a median of four days, compared with a median of 11 days for those not given the drug.
NEW POSSIBILITIES: Efforts are also on to develop a drug from scratch. At the Quantitative Biosciences Institute in the University of California, San Francisco, researchers are identifying proteins inside the cell that the virus uses to set its replication machinery rolling. They are now exploring if targeting any of these proteins would halt the march of the virus.
How far has work on a vaccine progressed?
US: A Phase 1 clinical trial has begun in Seattle, funded by the National Institute of Allergy and Infectious Diseases (NIAID). ”The open-label trial will enroll 45 healthy adult volunteers ages 18 to 55 years over approximately 6 weeks. The first participant received the investigational vaccine today,” the NIH said in a statement. The vaccine, mRNA-1273, was developed by NIAID scientists and collaborators at the biotech company Moderna.
CHINA: Researchers at the Academy of Military Medical Sciences, affiliated to China’s People’s Liberation Army, have received approval for vaccine trails, which will recruit 108 people between March and December. It will be partnered by Hong Kong-listed firm CanSino Biologics. According to an article in the People’s Daily, scientists are exploring options such as using the virus minus its potent elements, or using other attenuated (rendered harmless) vaccines, to introduce the virus into the body to generate a natural immune response against an actual infection.
What has been India’s experience?
Last week, doctors at the SMS Hospital is Jaipur administered the lopinavir-ritonavir combination on an Italian couple, aged 70 and 69, after they had been put on ventilators. Both were discharged after testing negative twice for the virus, as per the established protocol. The man died on Friday. Replying to a question, Lav Agarwal, joint secretary in the Health Ministry, said: “The Italian tourist who died in Jaipur was a 70-year-old chain smoker; he had tested negative for the coronavirus twice. He died of cardiac arrest while getting treatment for other ailments in another hospital. How can he be counted as a COVID-19 case?”
The government has revised its clinical management guidelines for COVID-19: “The use of Lopinavir/ Ritonavir in PEP regimens for HIV (4 weeks) is also associated with significant adverse events which many a times leads to discontinuation of therapy. In light of the above, Lopinavir/ Ritonavir should ONLY be used with proper informed expressed consent on a case to case basis for severe cases, within the under-mentioned framework along with supportive treatment as per need.” The combination is to be used in patients who have hypoxia, hypotension, new onset organ dysfunction (one or more) and also in certain “high risk groups”. Indian express
