The Oxford University study, for the first time, raises the issue of blood clotting risks in US manufactured vaccines based on a mRNA platform, a novel and previously untested technology. The study, based on data from over 35 million people, was published on 15 April.
The Sputnik V developers added that the risk of an individual developing cerebral vein thrombosis, a main reason why many regulators recommended the suspension of the use of vaccines produced by AstraZeneca and Johnson & Johnson, "appears to be very similar for AstraZeneca’s vaccine (5 in a million) as for Pfizer’s and Moderna’s mRNA vaccines (4 in a million)."
Amid a controversy over rare blood clotting events during vaccine use, U.S. regulators this week recommended pausing the use of Johnson & Johnson's COVID-19 vaccine as they investigate these cases. Earlier, Europe's drug regulator, the European Medicines Agency (EMA), said it had found a possible link between AstraZeneca's vaccine and very rare blood clots in some adults who had received the shot. The announcements led to several countries delaying the rollout of the Johnson & Johnson and AstraZeneca vaccines. Both vaccines use an adenoviral vector based platforms.
In early 2021, data stolen from the EMA’s servers during a hack appeared on the web revealing that Pfizer, an mRNA vaccine manufacturer, faced serious problems during the switch between lab and full-scale production for the mass market. The data showed that RNA integrity of the full-scale production samples decreased drastically, resulting in a subsequent decrease in safety. Moreover, the low integrity combined with high dosage means that the patient receives more truncated RNA, which does not create COVID-19 immunity and causes additional harmful stress on human immunity instead.