COVID-19 vaccines since their inception and rollout, have changed the course of the pandemic. Prior to the vaccines, we relied on social distancing measures to help reduce the spread of the virus and a handful of imperfect treatment options to treat those unlucky enough to become sick with it.
It is fair to say vaccines have saved countless lives.
Now French pharmaceutical company Valneva is throwing its hat into the vaccine ring, but it has a vaccine with a difference. Rather than induce an immune response that targets just the spike protein of the coronavirus, the Valneva vaccine, also known as VLA2001, stimulates an immune response to the entire virus, and that might just give it an edge over its competitors.
It is different in that it uses the tried and tested method of taking the whole of the coronavirus and inactivating it so that it can no longer cause illness. It then combines with an adjuvant, a substance that helps it enter human cells effectively.
A similar technique is used to make flu and polio vaccines. The idea is that by introducing a whole coronavirus into the human body, albeit one which has been inactivated and cannot cause illness, the immune system will recognise the whole virus as foreign and not just the spike proteins. This will give a much broader immune response and increase the memory cells that can recognise different parts of the virus should the vaccinated individual become infected with the real coronavirus.
The company say the advantage to this is that should any mutations arise on the spike protein that render it unrecognisable to the vaccine, the Valenva-induced immune response is broad enough to be able to recognise other parts of the virus so the immune reaction will still be effective.
Phase-three trials for the Valneva vaccine were carried out on more than 4,000 patients aged 18 years and older across 26 sites in the United Kingdom. The trials compared the immune response rates with those vaccinated with the Oxford AstraZeneca vaccines and results showed that VLA2001 generated a stronger immune response than the AstraZeneca vaccine – with higher levels of neutralising COVID-19 antibodies in the blood.
Researchers also found no severe cases of COVID-19 among participants receiving the Valneva vaccine, despite the Delta variant being in circulation during the trial.
A jab that produces a good immune response and may be able to protect against future mutations of the coronavirus is certainly a welcome addition to our vaccine arsenal. And with the shapeshifting nature of the virus, it is worth investing in vaccines that do not rely on just one part of its structure to generate protection. The Delta variant has taught us not to underestimate the coronavirus and with many poorer countries yet to vaccinate significant parts of their populations, there is a higher chance of new mutations arising.
But it is not without its controversy. The UK, which initially put in an order for 100 million doses, recently cancelled that order over allegations of breach of contract, something the pharmaceutical company strongly denies. The contract Valneva has with the UK government lists a broad range of potential breaches and it is unclear which one the government is referring to, but “supply issues” have been mentioned.
Despite this, the manufacturers have applied to the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) for approval, and expect to receive it by the end of the year. They are also preparing to submit a request with the European Medicines Agency. If they get that European approval, the UK government may well end up regretting their decision to cancel the order as the vaccine is likely to be snapped up by other countries.
Progress report: Promising results for the COVID-19 vaccines as a nasal spray.
Most vaccines are given as an intramuscular injection, though some, like the polio vaccine, are given orally. Most children in the UK are given the flu vaccine as a nasal spray.
Nasal vaccines have their own advantages, one of which is the option of self administration. Many bacteria that affect the respiratory system are breathed in, so the lining of the nasal passage and the airways are packed with immune cells to protect us from invading germs. Studies have shown that the flu vaccine given as a nasal spray not only induces a good immune response all over the body, but also locally around the nasal passageways, the doorway to respiratory infections.
One of the questions I am constantly being asked is: When will the COVID-19 vaccine become available as a nasal spray? For those who are needle phobic, it is an ideal way to administer a vaccine. And years of giving out the flu vaccine as a nasal spray to children have taught me that it is much easier than using a needle.
So it will be good news for many that a recent study led by the US-based National Institute of Allergy and Infectious Diseases (NIAID) has found giving the Oxford AstraZeneca vaccine as a nasal spray reduced viral shedding in animal models. The study initially looked at hamsters, separating them into two groups: one was given the COVID-19 vaccine as an intramuscular injection, the other as a nasal spray. Both routes of administration produced high antibody levels, but the nasal spray outperformed the injection.
It then went on to compare unvaccinated monkeys with those who were given the nasal spray. Both sets of monkeys were exposed to the COVID-19 virus, the vaccinated monkeys had a low viral load in their noses and lung tissue, and none of them developed symptoms of pneumonia, while three of the unvaccinated monkeys did. Having a low viral load present in the nose after a nasal vaccine may be a game changer as it could seriously reduce risk of onward transmission to other people.
Spurred on by the results of animal studies, researchers at Oxford University set up a phase-one trial looking at the effectiveness of the nasal spray vaccine in adult humans.
Thirty healthy volunteers aged between 18 and 40 were enrolled and investigated for the level of immune system responses generated by the vaccine using this delivery technique, as well as monitored for safety and for any adverse reactions. If the results of this small clinical trial are as promising as the animal trials have been then it may make it easier to vaccinate those who are afraid of needles. If nasal vaccines do cut transmission rates then that could change the course of the pandemic.
