From UPSC perspective, the following things are important :
Prelims level : Not much.
Mains level : Paper 3- Vaccine development and trials.
The world is dealing with an unprecedented and unimaginably serious crisis. Therefore, the speed of vaccine development is crucial.
Speeding up the vaccine development
- Availability of rationale and information: The race for developing an anti-COVID-19 vaccine has begun. Reasonable scientific rationale and the information needed for vaccine development are available to all stakeholders in academia and industry.
- Vaccine platforms: A large number of candidate vaccines based on different vaccine platforms, including delivering the virus genetic materials (RNA, DNA) or using synthetic biology to produce key viral proteins, have already been developed.
- Phase-I safety trials of an experimental vaccine, jointly developed by scientists at the National Institute of Health and at Moderna, a biotechnology company, has already been administered to healthy volunteers for its safety and immunogenicity.
- The speed with which the experimental vaccine has entered safety trials is unprecedented.
- Another vaccine jointly developed by China’s Academy of Military Medical Sciences and CanSino Biologics has reportedly been cleared for early-stage clinical trials.
- Development in India: The Serum Institute of India has also recently announced its readiness to start safety trials following animal experiments.
- According to a World Health Organization (WHO) report, more than 20 vaccine candidates are in advanced stages of development and will be ready for Phase-I safety trials.
- However, it is also clear that it will not be possible to roll-out any efficacious vaccine for at least another year.
Questions that need to be answered
- While these developments are encouraging, several questions will need to be answered for this vaccine development to move further.
- Triggering immune response safely: Although it is quite evident that humans mount a strong immune response and clear the viral load, the nature of the immune response and how to trigger it safely through vaccination will be key questions to address.
- Duration of the acquired immunity: How long the acquired immunity in humans will last is another important question to be asked before experimental vaccines move forward.
- We will need to know this because if the immunity is transient, then humans will be susceptible to reinfections.
- Ensuring no disease enhancement: Before moving to Phase-II trials in a large number of healthy volunteers, we also have to ensure that the immune response induced by vaccination does not lead to any disease enhancement.
Repurposing the already available drugs
- Therapeutic interventions, not only for curing severe cases of the disease but also for protecting all front-line healthcare workers, are urgently needed.
- Using already approved drugs: Since developing new drugs is a complex and lengthy process, scientists and pharmaceutical companies have rushed to investigate and use drugs that have already been approved by regulatory authorities.
- Using available molecular and structural biology information on the virus, a group of scientists have analysed all interactions of the viral proteins with human proteins that are crucial for the virus to enter human cells and use the host cell machinery to rapidly reproduce itself.
- Of the nearly 70 short-listed molecules that may interrupt these key interactions, 24 happen to be already approved drugs which can now be tested in laboratory animal models as well as humans.
- However, the re-purposing of several drugs, alone or in combinations to treat COVID-19 patients, have already been reported.
- More confusion than hope: There are many success stories of curing patients of COVID-19 doing the rounds in different parts of the world, but these have managed to create more confusion than hope.
- Without any appropriate controls, careful dosing and safety concerns, such small experiments can only do more harm than good.
Controlled randomised trials
- Given the urgency of finding a cure, it is absolutely necessary to find out unequivocally what works well and what does not. For that conducting carefully controlled randomised trials is the only way to go.
- In a welcome move, the WHO has announced clinical trials called the ‘Solidarity Project’.
- Under this project four drugs or drug, combinations will be tested in many countries around the world.
- These candidates include the anti-Ebola drug, Remdesivir, Chloroquine, anti-HIV drugs, and the Ritonavir/Lopinavir combination, with or without Interferon-beta.
- The European counterpart of the trial, Discovery, will conduct these trials in countries including France, Spain, Germany and the U.K.
- The pharma company Roche has also decided to initiate large, randomised Phase-III trials of its arthritis drug Actemra for its safety and efficacy in adult patients with severe COVID-19 pneumonia.
- It is complex and tedious to conduct randomised, large multi-centric trials.
- Quickly getting all the stakeholders together is laudable and underscores the notion that everyone needs to fight the deadly virus together. Hopefully, these trials will lead to tangible drug therapies against COVID-19.
It is most heartening to see scientists in academia and industrial partners coming together to fight a monumental public health crisis. The battle between pathogens and humans will continue but let us hope that we win the present one sooner than later.