Johnson & Johnson arrives, methods of use and advantages of the fourth vaccine approved in Italy

The arrival of the vaccino Johnson & Johnson it could represent a small turning point in a slower and more complicated vaccination campaign than expected. Already this week they will be available in Italy the first 184 thousand doses of the 400-500 thousand expected by the end of April and administrable from 18 years upwards.
The Johnson & Johnson vaccine is the fourth vaccine available in our country after Pfizer, Modern e AstraZeneca. It was approved by the European Medicines Agency on 11 March 2021 and soon after by the Italian Medicines Agency (Aifa).

Not only is it the only single-dose vaccine available against Covid – that does not require a recall after weeks – but it can also be easily stored in the refrigerator between 2 and 8 degrees, which could finally facilitate the extension of the practice of vaccination also to general practitioners and authorized pharmacies.

HOW THE JOHNSON & JOHNSON VACCINE WORKS
While the vaccines produced by Pfizer / BionTech and Moderna exploit a molecule of messenger Rna – with the task of introducing itself into the cells of the body and prompting them to produce the Sars-Cov-2 antigen which trains the immune system to search for and neutralize the virus – the J&J vaccine is a viral vector drug (adenovirus), like the one used by AstraZeneca: a DNA fragment corresponding to the spike protein is inserted into a virus harmless to humans and suitably modified. The virus infects human cells and the DNA is then read and transformed into protein. The latter is the antigen against which the immune response grows.

LEVELS OF EFFECTIVENESS
The J&J vaccine demonstrated an efficacy varying between 57 and 66%, depending on the different areas in which the third phase clinical trials were carried out: better results in the United States (with 86% protection against the most severe forms) and slightly lower protection in South Africa, against the variant identified for the first time in that country (57% against severe forms of the disease). In Brazil, on the other hand, the average efficacy was between 66.2 and 68.1% – respectively 14 and 28 days after vaccination – in preventing severe and critical forms.
By way of comparison, Pfizer’s vaccine is 95% effective, Moderna’s 94%, AstraZeneca’s 59.5%. If mRna drugs are confirmed to be more effective in preventing positivity, the viral ones have a similar ability to avoid severe forms of infection. The vaccine J&J manages to prevent severe forms of Covid up to 77% after 14 days from administration and at least 85% after 28 days. Not only that: the data did not show any decline in efficacy in subjects over 65.

RARE CASES OF THROMBOSIS AND EMA ASSESSMENT
In recent days, the Wash, the Safety Committee of the European Medicines Agency (Mother), initiated a review to evaluate reports of four severe cases of unusual blood clots with low platelets, in people who had received Johnson & Johnson’s Janssen Covid-19 vaccine.
“One of these thromboembolic events (formation of blood clots, resulting in obstruction of a vessel) occurred in a clinical study and three cases during the vaccination campaign in the United States. One of these was fatal», Ema explained in a note.
It is currently unclear whether there is a causal association between vaccination with Janssen and these conditions, but, as explained by the European Agency, “the Prac is investigating these cases and will decide whether regulatory action may be required, which usually consists of an update of the product information».
According to US authorities – where 5 million people have already been vaccinated with J&J – no proven link has been found between the vaccine and thrombosis.