After the outbreak of coronavirus, the world is suffering and searching for a vaccine. Millions of people have already lost their lives. The virus was first reported in late 2019 and very soon it spread all over the globe and was declared a pandemic. Due to its high communicable nature, countries were put on lockdown, and community gatherings were stopped.
Economies of several countries took a hit and even developed nations are facing recession. To minimize the loss, every major pharmaceutical company is in a race to develop the vaccine for the disease. Though Russia announced the successful development of a vaccine named Sputnik V, it is still a matter of concern among the experts due to its early development. Also, the Russian vaccine was not developed under the guidance of WHO, increases the concern more.
The Vaccine Race
Moreover, there are 6 vaccines currently undergoing phase 3 trials in the watch of the world health organization.
AstraZeneca, a major European pharmaceutical company was also in the list of early developments of the vaccine. Developed jointly by the researchers at the Oxford University and AstraZeneca, the vaccine was to become a gamechanger for the whole world. The vaccine was already undergoing phase 3 clinical trials but it is currently put on hold. According to AstraZeneca, a participant from the UK showed potentially unexplained illness including a serious neurological issue. The illness is the major cause of the derailing of the development.
Vaccine development currently in hold after reviewing
AstraZeneca officials in a statement informed that the standard review process triggered a hold to vaccination to mow review of safety data. The study is testing a coronavirus vaccine being developed by Oxford University of researchers and AstraZeneca at sites which include India, the United States, and the United Kingdom, where the adverse reaction was reported.
According to the start news, the nature of the safety issues and when it happened were not immediately known though there was an expectation that the participant will be recovered. The report said that the pause on the trail was having an impact on other AstraZeneca vaccine trials as well as on clinical trials being conducted by other vaccine makers.
Successful phase 1 to 2
Among the dozens of vaccines developed globally, the AstraZeneca Oxford University vaccine against coronavirus is seen as a strong contender. Following successful phase 1 and 2 of testing hopes have been high that the vaccine might be one of the first to register and hit the market.
Also, the vaccine of AstraZeneca was undergoing trials in India by the Serum Institute of India. Serum Institute of India is one of the major manufacturers of vaccines and immunobiological drugs in India. Trials undergoing in India are also put to hold. The Drug Controller General of India (DCGI) sent a notice to the Serum Institute seeking information about the illness of person participating in trials in the UK.
Testing has involved around 30,000 participants
The move to phase 3 testing of the vaccine in recent weeks has involved around 30,000 participants in the US, India, UK, Brazil, and South Africa. Phase 3 testing of vaccines offers to involve thousands of participants. It can last for several years.
The cause of the illness is not confirmed
The New York Times report says that a participant in the UK trial has been diagnosed with transverse myelitis, an inflammatory syndrome that affects the spinal cord. Currently, AstraZeneca is reviewing the cause of the illness. As there are chances of illness occurring in participants due to viral infections. An independent investigation will work to find out if there was any link to the vaccine
What is vaccine trial –
Vaccine trials are clinical trials done before releasing the vaccine for public usage. It aims to make the new vaccine safe and efficient for human usage before its registration. Vaccines contain a dead or weak strain of the virus responsible for the disease.
Thus it becomes important to check the effects on a human before public usage. Pharma companies carry out preclinical evaluations. These evaluations include high throughput screening and selecting the proper antigens to invoke an immune response. Companies carry out trials in several stages which help to determine the approximate dose ranges and proper drug formulations. Firstly these vaccine candidates are tested on laboratory animals. After successful results, they move for phase 1 trials which includes human participants.
The three phases of trials –
Phase 1 – Phase 1 trial consists of introducing the drug to assess it’s safety on healthy people. It involves an escalation study, which is used in mainly medicinal research trials. In this phase, the drug is introduced into a small cohort of healthy volunteers. The escalation trials are done in order to find out any adverse effects of the vaccine. In the escalation trials, participants are given drug dosage at regular intervals with increasing the dosage each time. It includes two or three groups of 10 healthy participants.
Phase 2 – Phase 2 trials rely on the results from phase 1 trials. Immunogenic and toxicity results in participants from phase 1 trials are generally checked. This phase usually consists of more healthy participants in the target population. Phase 2 consists of around hundreds of people to determine reactions in a more diverse set of humans and test different schedules.
Phase 3 – Phase 3 testing continues to monitor toxicity, immunogenicity, and serious adverse effects on a much larger scale. In this stage, it is determined that the vaccine must be shown to be safe and effective in natural disease conditions. Vaccine escalation testing aims before being submitted for approval and then general production.
Phase 4 – Phase 4 testings are typically monitored stages that collect information continuously on vaccine usage. It also collects information about the adverse effects, and long term immunity after the vaccine is licensed and produced in the markets.
Vaccine trials may take months or years to complete. Experts say that a sufficient time period should elapse for the subjects to react to the vaccine and develop the necessary antibiotics.