British-Swedish biopharmaceutical firm AstraZeneca PLC, working with a team of the University of Oxford, has temporarily paused the clinical trial of its coronavirus vaccine in the UK after one of the volunteers developed an "unexplained" illness. AstraZeneca and the Oxford University team is a frontrunner in the global race for coronavirus vaccine.
A spokesperson of AstraZeneca described the pause as, "a routine action which has to happen whenever there is a potentially unexplained illness in one of the trials, while it is investigated, ensuring we maintain the integrity of the trials". The development comes after AstraZeneca and eight other drugmakers vowed to uphold the highest ethical and scientific standards in developing their vaccines on Tuesday.
However, the pause in trials is certain to trigger concerns as the vaccine being developed by Oxford-AstraZeneca is most closely followed globally.
Here are the top developments related to the vaccine and what the pause really means:
1. Adverse reaction in a participant: On Tuesday, a spokesperson of AstraZeneca informed that an adverse reaction was observed in one of the volunteers in the United Kingdom. According to the pharmaceutical firm, the nature of the adverse reaction remained unknown, though the participant is expected to recover. The AstraZeneca's spokesperson added that pausing trial was common during vaccine development.
2. Illnesses happen in vaccine development: In large trials, illnesses will happen by chance and it must be independently reviewed to check this carefully, AstraZeneca said.
3. What a pause means: Clinical trials often involve a pause in recruiting new participants and dosing existing ones unless it's deemed in the interest of participant safety to continue dosing. However, it does not mean cancellation of vaccine development.
4. Impact on other AstraZeneca's trials: The finding will impact other ongoing AstraZeneca vaccine trials, as well as, clinical trials being conducted by other vaccine manufacturers.
5. Researchers analysing adverse reaction: According to Stat news, researchers running other trials are now looking for similar cases of adverse reactions by combing through databases reviewed by a so-called Data and Safety Monitoring Board.
Dr Ashish Jha of Brown University took to Twitter and wrote that the significance of the interruption was unclear but that he was "still optimistic" that an effective vaccine will be found in the coming months.
We have no idea whether this is a big deal or not— Ashish K. Jha (@ashishkjha) September 8, 2020
Science is hard. This is why we have to let the trials play out
I remain optimistic we will have a vaccine found to be safe and effective in upcoming months.
But optimism isn't evidence
Let's let science drive this process. https://t.co/1fBbMybC9W
Angela Rasmussen, a virologist at Columbia University in New York, tweeted that the illness may be unrelated to the vaccine, "but the important part is that this is why we do trials before rolling out a vaccine to the general public".
To clarify, this may not be a big deal. This type of pause normally happens when there is an unexpected severe adverse event. It may be unrelated to the vaccine, but the important part is that this is why we do trials before rolling out a vaccine to the general public.— Dr. Angela Rasmussen (@angie_rasmussen) September 8, 2020
Deborah Fuller, a University of Washington researcher said it was likely the unexplained illness was serious enough to require hospitalisation and not a mild side effect such as fever or muscle pain. "This is not something to be alarmed about," Fuller said.
Robert Booy, a University of Sydney professor of vaccinology stated that the trial might not resume for a month at least if the investigation into the participant provides "reassuring findings". Booy added if further incidents of the same adverse reaction were reported then vaccine's safety would come under a cloud.
About AstraZeneca vaccine:
AstraZeneca is one of nine companies currently in late-stage Phase 3 trials for their vaccine candidates. The vaccine, a known as AZD1222, uses an adenovirus that carries a gene for one of the proteins in SARS-CoV-2, the virus that causes Covid-19. The adenovirus is designed to induce the immune system to generate a protective response against SARS-2. In August, AstraZeneca recruited 30,000 volunteers across 62 sites in the US for its largest study of the vaccine. It is also testing the vaccine in India, US, UK, Brazil and South Africa.
According to The Lancet report, the Phase 1/2 of AstraZeneca reported that about 60 per cent of 1,000 participants given the vaccine experienced side effects. All of the side effects, which included fever, headaches, muscle pain, and injection site reactions, were deemed mild or moderate. However, all of the side effects reported also subsided during the course of the study.
In India, Pune-based Serum Institute of India (SII) has started conducting Phase 2/3 human trials for the COVID-19 vaccine developed by the University of Oxford and AstraZeneca. The SII has signed an agreement to manufacture the potential vaccine developed by Oxford University in collaboration with AstraZeneca.
In fact, SII chief Adar Poonawalla tweeted yesterday, "Proud and excited for the next few months and looking forward to the vaccine".