Both vaccines against COVID-19 are based on messenger RNA but differ in their preservation characteristics or price.
On January 6, the European Medicines Agency (EMA) approved Moderna's vaccine. It involved the authorization to use a second drug against COVID-19 after it was approved in December and began to administer the vaccine developed by Pfizer and BioNThec. For the moment, Moderna's is scheduled to arrive in Spain in seven or ten days, according to the Minister of Health, Salvador Illa, revealed on Wednesday.
In total, Brussels has already acquired 460 million doses of both vaccines (300 million from Pfizer / BioNTech and 160 million from Moderna), which share certain characteristics despite differing in many respects, especially in storage conditions.
Both use messenger RNA
Pfizer / BioNTech and Moderna's coronavirus vaccines have something in common: they both use messenger RNA, that is, "they contain part of the 'instructions' of the virus that causes COVID-19," according to the European Commission. This "allows the body cells to produce a protein that is unique to the virus. " In this way, when a person comes into contact with the virus, their immune system recognizes that this unique protein should not be in the body and responds by producing natural defenses against infection, preventing it from spreading.
This is also the mechanism used by the vaccine being developed by the German biopharmaceutical company CureVac, with which the Commission has also signed a contract but has not yet requested the EMA's approval.
Both coronavirus vaccines are more than 93% effective and very similar. According to Pfizer, it is effective up to 95% based on trials with more than 40,000 people. Of these, 18,100 received the vaccine, and only eight fell ill with coronavirus, one of them had a more severe infection, although no one needed hospitalization. Moderna's coronavirus vaccine, meanwhile, is 94.5% effective. In their trials, 30,000 volunteers participated and of the 13,900 vaccinated, only 11 contracted the disease, without there being any severe case.
Furthermore, no serious adverse side effects were detected with either vaccine, other than pain or swelling at the injection site, fever, muscle pain, or headache.
Different storage conditions
Transporting the vaccines against COVID-19 to all countries will pose a huge logistical challenge, especially for preserving the product, where the main difference between the two mentioned vaccines lies. In this regard, Pfizer's is much more challenging to distribute since it needs extreme temperatures, around 70 degrees below zero, to keep it in good condition. The Moderna, on the other hand, is kept between 15 and 25 degrees below zero and can be even 30 days in a regular refrigerator, with temperatures ranging between 2 and 8 degrees.
Both require two doses, but at different times
Regarding the administration, there are small differences in the period in which the doses are administered. Both require two intramuscular injections to be effective in granting immunity to whoever receives them. While the interval is 21 days between the first and second doses for the coronavirus vaccine developed by Pfizer and BioNTech, it is of 28 days for Moderna.
Pfizer's vaccine is cheaper
In addition to its storage conditions, price is another determining factor in making a vaccine accessible to certain countries. In this case, although it is more complicated logistically, the one from Pfizer and BioNTech is cheaper since each dose would cost about 17 euros. The Moderna, on the other hand, is the most expensive of all those that are being developed, since it would reach 31 euros per dose. On the contrary, the cheapest is the one created by the University of Oxford and AstraZeneca, whose price is about three euros per dose.