It seems that coronavirus vaccines are like buses – you wait ages for one, then three come along at one.
Following news that Pfizer and BioNTech have produced promising results from an RNA-based vaccine, American company Moderna has announced a vaccine trial which it claims is 95 percent effective, and global pharmaceutical company Janssen has begun clinical trials of its potential vaccine involving 6,000 volunteers across the UK.
The Moderna trial involved 30,000 people in the USA, with half being given two doses of the vaccine, four weeks apart, and the rest administered a placebo. The analysis of the vaccine’s effectiveness was based on the first 95 to develop Covid-19 symptoms, only five of whom had been given the vaccine. From this the company derives a figure of 94.5 percent effectiveness, though this does seem a small sample group to calculate from.
Moderna says that there were 11 cases showing severe symptoms of COVID-19 in the trial, none of them individuals who had received the vaccine.
Dr Stephen Hoge, Moderna’s president, told BBC News that he “grinned ear to ear for a minute” when the results came in.
He said: “I don’t think any of us really hoped that the vaccine would be 94% effective at preventing Covid-19 disease, that was really a stunning realisation.”
Moderna says it will apply to regulators in the US for permission to distribute the vaccine in the coming weeks. It expects to have 20 million doses available in the country, and up to one billion doses available for use around the world after approval has been granted in other countries.
The number of infections in the US has reached new heights, surpassing 160,000 cases in one day.
Dr Anthony Fauci, the top US infectious diseases expert, has warned that the country faces “a very challenging and ominous situation” as it approaches winter.
The UK has announced that it has ordered 5m doses of the Moderna vaccine, enough to treat 2.5m people. Several different vaccines will be needed to deal with the pandemic, as no one company will be capable of manufacturing enough to serve the whole population, and none will be 100 percent effective.
It’s claimed that the Moderna vaccine has shown only slight, short-term side-effects and is as effective for older subjects as it is for other age groups, though it’s difficult at this stage to say how long immunity could last, or whether it will prevent the spread of the virus.
LIke the Pfizer/BioNTech vaccine, the Moderna vaccine uses the approach of using part of the COVID-19 virus’s genetic code to provoke an immune response in the subject, manufacturing viral proteins and infection-fighting T-cells. The main difference is that while Pfizer’s needs to be stored at extremely low temperatures, Moderna’s will remain stable at -20C for up to six months, and can be kept in a standard refridgerator for up to a month.
The Janssen Pharmaceutical Companies, part of Johnson & Johnson, is the latest study in the UK, jointly funded by the UK government’s Vaccine Taskforce, to test the safety and effectiveness of a potential COVID-19 vaccine. It is the third potential vaccine to enter clinical trials in the UK, alongside US biotech company Novavax and University of Oxford / AstraZeneca whose studies are currently ongoing.
Meanwhile a Chinese coronavirus vaccine is showing promise according to preliminary study results. Researchers say that it induces an immune response in healthy volunteers and appears to be safe.
The Chinese vaccine, CoronaVac, is in phase one/two trials. It uses an inactivated SARS-CoV-2 virus to provoke an immune response, and has been tested on 700 healthy volunteers aged 18-59 recruited in China between April 16 and May 5.
Preliminary results published in The Lancet Infectious Diseases suggest that CoronaVac appeared to be safe and well tolerated at all tested doses, and shows an immune response within 14 days, though at lower levels than those seen in people who had been infected by and recovered from Covid-19. Further studies will be needed to determine the results with other age groups and those with pre-existing medical conditions.
Professor Fengcai Zhu, joint lead author of the study, from the Jiangsu Provincial Centre for Disease Control and Prevention, Nanjing, China, said: “Our findings show that CoronaVac is capable of inducing a quick antibody response within four weeks of immunisation by giving two doses of the vaccine at a 14-day interval. ‘
“We believe that this makes the vaccine suitable for emergency use during the pandemic. In the longer term, when the risk of Covid-19 is lower, our findings suggest that giving two doses with a one-month interval, rather than a two-week interval, might be more appropriate for inducing stronger and potentially longer-lasting immune responses.
“However, further studies are needed to check how long the antibody response remains after either vaccination schedule.”
The news comes as UK Prime minister Boris Johnson has been self-isolating after meeting with an MP ho was later diagnosed with coronavirus. The PM was contacted by NHS Test and Trace on Sunday and will continue working from No 10 Downing Street, and attending the House of Commons via video conferencing.
Mr Johnson was told he needed to self-isolate after spending time with Tory MP Lee Anderson, who reported that he had lost his sense of taste the next day.
If you are told by NHS Test and Trace that you were in contact with a person who tested positive, as in Mr Johnson’s case, you must self-isolate for 14 days from the date you last met. Mr Johnson will have to remain at No 10 until 26 November. He spent seven nights in hospital with coronavirus in April, three days of it in intensive care.
Find out more here about the coronavirus vaccines announced by Pfizer and BioNTech, and American company Moderna, and the government’s plans to distribute them.