JAKARTA – A number of countries most affected by the Covid-19 pandemic at the end of this week will have access to vaccines. The latest is the United States (US), which through the Food and Drug Administration (FDA) has authorized the use of mRNA-1273 – a vaccine candidate made by the American biotechnology company Moderna – as a safe and effective vaccine.
This paves the way for an emergency vaccine authorization, a decision the FDA will make after an outside advisory panel meets on Thursday.
Where permitted, the Moderna vaccine will follow in the footsteps of the use of the vaccine from Pfizer-BioNTech, which the US and UK have begun to give to the general public.
Singapore has also approved the use of the Pfizer-BioNTech vaccine, with first deliveries expected later this year.
Other countries such as Canada, Saudi Arabia, Mexico and Kuwait have also permitted the use of the Pfizer-BioNTech vaccine. A large group will also follow soon, if the EU gives final approval, which could come as early as 23 December.
Another COVID-19 vaccine, developed by Sinovac Biotech China, is also in its final stages of trials. Indonesia already has 1.2 million doses of CoronaVac, the vaccine being tested since last August.
The following are the differences between the three Covid-19 vaccines quoted from Channel News Asia:
PFIZER-BIONTECH
The Covid-19 vaccine developed by US pharmaceutical giant Pfizer and Germany’s BioNTech is the first Covid-19 vaccine approved by the US FDA for emergency use.
How it works: The Pfizer-BioNTech vaccine uses messenger RNA (mRNA) technology. The mRNA vaccine teaches our cells to make proteins that trigger an immune response in our bodies. This is different from traditional vaccines which introduce weak or inactive germs into our body.
Storage: Pfizer-BioNTech’s Covid-19 vaccine needs to be stored at temperatures of minus 70 degrees Celsius, which presents logistical challenges, especially for poor countries.
Benefits: 95 percent
Launch: Britain was the first country in the world to launch a vaccination shot on December 8, with the US following about a week later on December 16. Singapore, Canada, Mexico and Saudi Arabia have also allowed the use of the Covid-19 vaccine produced by Pfizer-BioNTech.
MODERN
Preliminary results from the Moderna vaccine described a month ago by leading US infectious disease expert Anthony Fauci are “very impressive”.
How it works: Just like the Pfizer-BioNTech vaccine, the Moderna vaccine uses mRNA technology.
Storage: Can be stored for 30 days with refrigeration, six months at a temperature of minus 20 degrees Celsius.
Efficacy: 94.5 percent
Launch: Not yet known.
SINOVAC
Developed by China Sinovac Biotech, the vaccine known as CoronaVac is currently undergoing phase 3 clinical trials in places like Brazil and Indonesia.
Apart from Brazil and Indonesia, a number of other countries planning to use Sinovac are Turkey and Chile.
How it works: The Sinovac vaccine uses an inactivated vaccine technology, which uses a live, attenuated form of the virus to stimulate our bodies to produce an immune response. This vaccine is similar to the flu and chickenpox vaccines.
Storage: Vaccines can be stored at normal refrigerator temperature of 2 to 8 degrees Celsius and can remain stable for up to three years. This may be an attractive option for places where access to cooling is difficult.
Benefits: Unknown
Launch: Not yet known.
Of the three vaccines above, a number of countries have given the green light for the use of the Pfizer-BionTeceh vaccine given the percentage level of efficacy which reaches 95%. Even China, which has its own vaccine, also ordered the Pfizer vaccine.
“With mRNA technology, the clear advantage is that large quantities of vaccines can be produced quickly, without the use of cell cultures and other potentially toxic substances,” said Professor Artur Summerfield, deputy chief director of immunology at the Swiss Institute of Virology and Immunology.
“In general, the results published so far have shown a good antibody reaction, as well as a good cellular immune response. Both are important against the virus, “he added.
Even though it has properties of up to 95%, it does not mean that the Pfizer vaccine has no side effects. Two health workers in Alaska experienced allergic reactions after receiving Pfizer injections this week, and severe allergic reactions were also reported in two health workers in the UK last week.
These events are still being investigated, and it is unclear if there was a component or ingredient in the Pfizer vaccine that could have caused the reaction.
For the Moderna vaccine itself, the FDA has just issued a recommendation for its use, as quoted from NBC News
The Moderna vaccine works in the same way as the Pfizer vaccine, using small pieces of the genetic code called messenger RNA, or mRNA, to encourage the immune system to produce antibodies against the coronavirus, without using bits of the virus itself.
Clinical trials show the vaccine is 94 percent effective in preventing symptoms of illness within two weeks of the second dose.
At an advisory board meeting Thursday, representatives from Moderna said that among the more than 30,000 clinical trial participants, no cases of anaphylaxis appeared to be linked. (One participant developed anaphylaxis 63 days after getting the second dose. The reaction usually occurs immediately after exposure to the allergen.)
There is also discussion about whether people who have recently undergone cosmetic fillers are at greater risk of temporary facial swelling after injection.
Three people in the Moderna clinical trial who had facial swelling also had fillers, either on the cheeks or on the lips. The procedure was completed between two weeks and six months prior to vaccination.
CM
(yao)
–
