Coronavirus - When Will We Have the Vaccine?

As the COVID-19 pandemic peaks, we ask how long it will be before a vaccine is available to the general public

Though reports as of April 21st suggest that we have passed the peak of the coronavirus epidemic in the UK, no-one believes that the end is in sight yet. But if an effective vaccine is the only real solution to coronavirus – when will we have the vaccine?

While we’re still in lockdown, it’s clear that what’s needed to get society back to normal is increased testing, followed by an effective vaccine. So what’s the hold-up?

There are over 50 research groups working on vaccines, with UK teams leading the field. Researchers at Imperial College and Oxford are working on two new directions. Professor Robin Shattock of the Department of Infectious Disease at Imperial College says his team has been working on animal testing since February, and is calling for volunteers for human testing starting in June, with the hope that a vaccine may be ready in September.

The Imperial vaccine uses RNA to deliver virus protein in a lipid droplet – this is a relatively simple manufacturing process and could deliver 1m doses from 1l of material. This low-dose synthetic vaccine would be relatively easy to produce in scale.

Target

Robin Shattock describes COVID-19 as “Not as difficult a target as some we have seen”, as it seems less inclined to mutate than, say, influenza or HIV. However he welcomes an alternative approach being taken by Oxford researchers using viral particles, suggesting that the two vaccines may both be useful, forming a primer and a booster treatment.

However, even Professor Shattock is reluctant to promise definite results – “There are many risks of failure along the way” he warns.

Meanwhile researchers from the Oxford vaccine team say they are “Delighted with Tuesday’s announcement by the Secretary of State for Health of funding for the evaluation of the new COVID19 vaccine.” The group, working with the Jenner Institute, started work on developing a vaccine to prevent COVID-19 on 20th January 2020 and is led by Prof. Sarah Gilbert, Prof. Andrew Pollard, Prof. Teresa Lambe, Dr Sandy Douglas, Prof. Catherine Green and Prof. Adrian Hill.

The clinical trial is being conducted in collaboration with Prof. Saul Faust at University Hospital Southampton NHS Trust and Dr Katrina M. Pollock at NIHR Imperial Clinical Research Facility, Imperial College.

In its statement, the Oxford group added “Our researchers are working with great care, and due haste, to get this vaccine ready to be used in the clinical trial. Experts have estimated that it will take 12-18 months to develop a new vaccine at high speed. Under normal circumstances, most vaccine development programmes take more than five years, so this is still a considerably accelerated timescale.

Development

“This 12-18-month prediction includes the time taken to develop manufacturing processes to produce the vaccine on a larger scale, as well as preclinical testing in animals and evaluation of the vaccine in human participants in a clinical trial.

“Scientists need to assess the safety and efficacy of the vaccine over a number of weeks and months through phase I, II and III clinical trials. If the vaccine is safe and efficacious, regulatory approval is needed before the vaccine can be deployed.

“This week we will start the process of vaccine evaluation in our first human studies and are currently focussing all efforts on preparing for the start of the trials. Although it seems like a very long time since the work started, in reality it is less than four months since we first heard of an outbreak of severe pneumonia cases, and began to plan a response.

“Our brilliant team has been working tirelessly to get to this point using our skills and experience in vaccine development and testing, and will do the best job possible in moving quickly whilst at all times prioritising the safety of the trial participants.”

Testing

Testing of the Oxford vaccine, named ChAdOx1, will follow standard trial timelines.

Phase I Vaccinate 510 volunteers aged between 18-55, half with the new COVID-19 vaccine and half with a control vaccine.

Phase II Extend the maximum age of trial participants to 55-70 years, then over 70.

Phase III Vaccinate 5000 volunteers aged over 18 years, half to receive the COVID-19 vaccine. Clear efficacy endpoints will be used to assess the effectiveness of the vaccine, and volunteers from phase I and II will be included in the follow-up.

The group says “The best-case scenario is that by the autumn of 2020 we could have an efficacy result from the phase III trial to show that the vaccine protects against the virus, alongside the ability to manufacture large amounts of the vaccine, but these best-case timeframes are highly ambitious and subject to change.

“Our ability to determine vaccine efficacy will be affected by the amount of virus transmission in the local population over the summer, and we are also beginning to consider initiating trials with partners in other countries to increase our ability to determine vaccine efficacy.”

Vaccine trials will be based in four centres, Bristol, Oxford, Southampton and London, and you can volunteer to participate in a trial here.

Symptoms

The genetic code for the coronavirus vaccine was cracked within weeks of it being isolated by Chinese researchers, but that doesn’t immediately promise an effective vaccine. Here’s why.

The symptoms of COVID-19 are similar to those of many other respiratory diseases, so testing is the only way to know for certain if someone is infected and needs to be isolated, or whether, for instance, a health worker is free of the virus and can continue to work safely.

The standard test searches for fragments of genetic material specific to the COVID-19 virus. This test involves swabbing the back of the throat or the nose and sending the swab to a lab for analysis.

Blood and urine tests don’t seem to be so effective; in fact they only detect the coronavirus is present in 50 percent of cases.

The usual test method, called polymerase chain reaction (PCR), takes several hours to complete, so it would obviously take a lab many weeks to run thousands of tests. The necessary expansion of labs to achieve this capacity, with all the space, equipment and trained technicians it requires, means that we can’t expect large-scale testing to be in place for some time.

We’re told that there will be 50 test labs running in the UK by the end of April, but so far the established ones don’t seem to be running at full capacity, whether for technical or administrative reasons.

There is a faster test technique, called loop mediated isothermal amplification (LAMP), which takes less than half an hour. Several groups around the world are working on handheld LAMP tests which could be used in homes or airports – but again, ramping up to testing in scale could take months.

Reliability

Adding to the problem is that question of how reliable this sort of test is. There are reports of many false positives and negatives coming out of China, but it’s hard to say whether this is because testing is being done too early, or samples aren’t being taken properly, or tests aren’t being processed efficiently.

In some countries, such as South Korea, up to 20,000 people a day are being tested, and the effectiveness of the system has been proven by the relatively controlled progress of the infection in that country. Other countries, including arguably the UK, made the mistake of not starting testing until the number of infections reached a higher stage.

Another type of test is an even faster system taking just 10-15 minutes based on detecting protein side-products of infection. They tend to be less accurate than genetic tests, and aren’t effective in the first two weeks of infection. However, these antigen tests, which detect two proteins known as IgM and IgG, are useful for checking if someone is currently infected, in the process of recovery, or has had the infection and recovered from it (since we continue to make antibodies after infection). The accuracy of this rapid testing has yet to be established, but they may have a role particularly in countries with less developed health services.

Recovery

While antibody tests will help us to calculate, for instance, mortality rates, what they don’t tell us is whether people who have recovered from the infection are then immune; in fact there are worrying signs coming out of China that it is possible to be infected again. If this is the case, it will obviously make it harder to reap any benefit from a process of testing.

So we’re back to the question of whether a vaccination, effectively a cure, is the only solution to the coronavirus pandemic.

Public health officials have been playing down hopes of the swift production of a vaccine, which were perhaps prompted by the relatively quick production of a vaccine to tackle the Ebola epidemic in West Africa in 2014-16; but that, as researchers pointed out, had been in development for five years before the outbreak.

Warnings that a COVID-19 vaccine may not be available to the public for 12 to 18 months have damped down hopes that there will be a quick ending to the current pandemic, though two vaccine candidates are already in early human trials, one in China and the other in the United States.

Hold-up

With some ill-informed public figures (including US President Donald Trump) promising quick results in the race for a vaccine, what is the actual hold-up? In fact, according to Dr. Greg Poland, director of the Mayo Clinic’s Vaccine Research Group, developing a successful vaccine can take “Ten to fifteen years and a billion dollars”.

Dr Poland’s argument is that it’s unsafe to speed up production of a vaccine in response to a current pandemic. “You don’t want to speed it up so much that you allow a bad vaccine to enter the market” he told US News. “The process of developing, testing and licensing a vaccine for widespread population use is designed to be slow, deliberative, peer-reviewed, reflective, evidence-based, so that we don’t make mistakes,” Poland said.

Dr Poland explains that going too fast could lead to a vaccine that’s not effective or, worse, can cause serious health problems.

Vaccine trials normally come in three phases.

• Phase I – takes about six months, testing whether the vaccine is safe.
• Phase II – takes about a year, checking how well the vaccine works in creating an immune response.
• Phase III – takes three years or more, tracking the effectiveness of the vaccine in preventing infection in people who are being exposed to the pathogen, and depends on the virus remaining active long enough for participants to be exposed to it.

Record

The trial vaccine new being tested in the US was developed at record speed by scientists at the U.S. National Institute of Allergy and Infectious Diseases (NIAID) and the biotech company Moderna, and its production in a couple of months is regarded as being dramatically fast.

“The reason we were able to get into trials so quickly is because this vaccine was modelled on other vaccines for influenza and Zika, using the same manufacturing process and the same technology, but just substituting the genetic code for this SARS-COV2 virus,” said Dr. Kathleen Neuzil, director of the University of Maryland’s Center for Vaccine Development and Global Health in Baltimore.

The initial trial has enlisted 45 healthy adults in Seattle, who are being tracked for about six weeks.

Vaccine

So what is the process of vaccine development, and what are the particular challenges of the coronavirus vaccine?

The COVID-19 virus infects lung cells using so-called “spike” proteins which surround the outside of the virus. These spikes bump into compatible receptors on the lung cells, tricking them into allowing the virus to enter and infect them.

The American vaccine being developed by NIAID/Moderna functions by teaching the body’s immune system to recognize these spike proteins and to destroy the virus.

The U.S. regulatory body, the Food and Drug Administration, has allowed the Phase 1 and Phase II stages of the trials to be combined for the sake of speed, but there are possible pitfalls to this approach; for instance if the vaccine proves not to provide lasting immunity, either because the immune response fades, or the coronavirus mutates in response to the vaccine’s process.

Dr Poland worries that concentrating on attacking the virus’ ‘spike’ proteins may be too narrow an option. In comparison, flu vaccines normally contain two antigens, in an attempt to prevent the virus mutating away from the subject’s immune responses.

The other main concern, the potential for unintended health issues caused by the vaccine, is underlined by fears that the vaccines used against the SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome) outbreaks – both respiratory coronaviruses like COVID-19 – may now be causing lung and liver disease themselves. Certainly that seems to be indicated by some animal testing.

Acceptance

“Something rushed out too fast that would have some significant side effect later would set back vaccine acceptance in an already vaccine-skeptical culture for decades,” said Dr Poland. He worries that if an imperfect COVID-19 vaccine is rushed out, it may prove ineffective in preventing infection, because the virus mutates around the vaccine. “A second strain develops next year that, when it infects people who have been immunized, they are not protected because of the false immunity they have or develop antibody-enhanced disease,” he said.

A second U.S. company, Inovio Pharmaceuticals, has announced that it is beginning Phase I clinical trials in healthy volunteers in Philadelphia and Kansas City. The Inovio vaccine uses a section of the virus’ genetic code, packaged inside a piece of synthetic DNA.

Having several vaccine candidates in development may well be the only way to guarantee long-term success, and in fact there are now over 50 development programs at work. But perhaps we shouldn’t be too eager to jump at the first one out of the gates.

So the answer to the question, coronavirus – when will we have the vaccine? seems to be that the race for a COVID-19 vaccine may well be, not a sprint, but a marathon.

Coronavirus – When Will We Have the Vaccine?