Vaccine Development for COVID-19
TOPIC: General Studies 2
- Global crisis – COVID-19
With confirmed COVID-19 cases worldwide surpassing 2.7 million and continuing to grow, scientists are pushing forward with efforts to develop vaccines and treatments to slow the pandemic and lessen the disease’s damage. Some of the earliest treatments will likely be drugs that are already approved for other conditions, or have been tested on other viruses.
The virus spreads easily and the majority of the world’s population is still vulnerable to it. A vaccine would provide some protection by training people’s immune systems to fight the virus so they should not become sick. This would allow lockdowns to be lifted more safely, and social distancing to be relaxed.
However, it must be emphasised that because vaccines are given to large populations, safety issues are paramount. The world is dealing with an unprecedented and unimaginably serious crisis. Therefore, the speed of vaccine development is crucial.
Decoding The Virus
Experts believe the genome sequencing of the new coronavirus provided by scientists in China shows it shares 79 percent of the same genetic material as Severe Acute Respiratory Syndrome (SARS) and 50 percent with Middle East Respiratory Syndrome (MERS), a zoonotic coronavirus that infects humans, bats and camels. This allows developers to use groundwork already created in in research for vaccines for those viruses. Australia’s national science agency CSIRO announced earlier this month that it has begun pre-clinical tests of a vaccine developed by Oxford University, U.K.
A striking feature of the vaccine development landscape for Covid-19 is the range of technology platforms being evaluated, including nucleic acid (DNA and RNA), virus-like particle, live weakened virus, and inactivated virus approaches.
Research is happening at breakneck speed. About 80 groups around the world are researching vaccines and some are now entering clinical trials.
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.
Of the eight trials currently enrolling volunteers, only three are in Phase 2. Of these, only the “Oxford Trial” (a Phase 1/Phase 2 hybrid) from the United Kingdom has prevention of Covid-19 infection, rather than a laboratory result, as the primary desired outcome.
- The first human trial for a vaccine was announced last month by scientists in Seattle. Unusually, they are skipping any animal research to test its safety or effectiveness
- In Oxford, the first human trial in Europe has started with more than 800 recruits – half will receive the Covid-19 vaccine and the rest a control vaccine which protects against meningitis but not coronavirus
- Another vaccine jointly developed by China’s Academy of Military Medical Sciences and CanSino Biologics has reportedly been cleared for early-stage clinical trials in which more than 100 healthy volunteers are scheduled to receive the vaccine.
- Australian scientists have begun injecting ferrets with two potential vaccines. It is the first comprehensive pre-clinical trial involving animals, and the researchers hope to test humans by the end of April
However, no-one know how effective any of these vaccines will be.
Vaccine Testing Phases
Vaccine testing typically begins with animal and lab testing before going on to different stages of human testing.
Phase A: Phase one trials are small-scale, usually involving few participants, to assess whether the vaccine is safe for humans.
Phase B: Phase two trials often involve several hundred subjects, and mainly evaluate the efficacy of the vaccine against the disease
Phase C: The final phase involves thousands of people to further assess the efficacy of the vaccine over a defined period of time, and can last several months
Even after the vaccine is ready, there are a lot of challenges, including whether the vaccine is effective in all populations, and if it can be used for different strains of the novel coronavirus, which might start mutating as time passes.
With the world joining hands to find a vaccine for Covid-19, all eyes are on India, the powerhouse of vaccine manufacturing. India produces 60 per cent of the world’s vaccines and accounts for 60-80 per cent of the United Nations’ annual vaccine procurement. A number of Indian companies have also helped over the years to produce and distribute vaccines to the world.
Six Indian companies are working on a vaccine for COVID-19, joining global efforts to find a quick preventive for the deadly infection spreading rapidly across the world. Nearly 70 ‘vaccine candidates’ are being tested and at least three have moved to the human clinical trial stage, but a vaccine for the novel coronavirus is unlikely to be ready for mass use before 2021.
Three approaches are being taken in drug development in the country:
- Repurposing of existing drugs: At least four drugs are undergoing synthesis and examination in this category
- Development of new candidate drugs and molecules are being driven by linking high performance computational approached with laboratory verification
- Plant extracts and products are being examined for general anti-viral properties
Several academic research institutions and start-ups have developed new tests, both for the Reverse transcription-polymerase chain reaction (RT-PCR) approach and for antibody detection, in diagnosis and testing. Capacity for both these tests has been enormously scaled up by linking laboratories across the country.
What works in India’s favour in the race for a vaccine?
An established wide global network: About 90 per cent of the company’s vaccines are sold in lower- to middle-income countries. It owns 160 global patents and sells products in over 65 countries.
India is ahead of the Covid-19 curve and should take the lead in the producing the vaccine. The most immediate need and role for India to play right now is “to enable large scale manufacturing, to enable rapid approvals, guidelines, and collective wisdom to deliver the appropriate vaccine.
Collaborations and partnerships: The strategic approach to vaccine development by Indian biotech companies is to collaborate with academia, universities, research organisations and virologists to develop vaccines in co-support. Once development is over, Indian companies have mastered the art of accelerating mass-production and distribution across the world.
The price factor: India has been able to achieve price affordability through the economy of scale. A classic example is the case of the Rotavac Vaccine for “rotavirus” infections. India was able to manufacture and sell at almost one-fifteenth of the then-market cost in 2013.
The Way Forward
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.
- Some early, but limited, studies from China have suggested that monkeys can be infected with this virus but can be protected from reinfection. 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.
- 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, as has been observed in cases of some experimental vaccines against the dengue virus, and in animal studies with an experimental vaccine against the SARS virus.
- 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 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. Many countries have already signed up for these trials and all drug companies, including CIPLA from India, have agreed to supply sufficient quantity of drugs needed.
Connecting the Dots:
- For decades, dengue fever, a viral infection common in tropical climates, has been known to cause a much more severe infection the second time certain people develop the disease. Can the vaccine end up making the infection more severe? Discuss.
- The cure must not be worse than the disease
- The battle between pathogens and humans
- New technology comes with a learning curve; that learning curve has a human prize.