AstraZeneca, second dose with vaccine mix: what Aifa says

AstraZeneca and second dose ‘mix’ with Pfizer or Moderna in the under 60s in Italy, in the opinion expressed by the Technical Scientific Commission (Cts) of the Italian drug agency Aifa on ‘heterologous’ anti-Covid vaccination, cited two studies that speak of ” good results in terms of antibody response and safety “. The document is attached to the ministry circular signed after yesterday’s Aifa go-ahead. Read also “Faced with a significant enhancement of the antibody response obtained with the first dose, suggestive of a booster effect, the vaccine mix (first dose with Vaxzevria * and second dose with Comirnaty *) – we read – presented a reactogenicity profile which, although characterized by a higher frequency in terms of local and systemic side effects of mild to moderate degree, appeared on the whole acceptable and manageable. On the basis of these studies it is believed that the available data may support the use of the Comirnaty vaccine and , by analogy, of the Moderna vaccine, as a second dose to complete a mixed vaccination course in subjects under the age of 60 who have already received a first dose of Vaxzevria vaccine “. The document mentions the two available studies – one Spanish and one English – on the basis of which the opinion of the CTS was expressed. “In addition to the biological plausibility” of the fact that “different methods of expression of the Spike protein in recipient cells are capable of inducing responses to largely overlapping epitopes, this approach was supported by clinical data deriving from two published clinical studies in recent weeks and conducted respectively in Spain and England and, which show good results in terms of antibody response and safety “, explain the experts in the opinion. The Spanish study CombiVacS is cited by the Cts of Aifa in the passage in which it mentions the antibody response of the mixed anti-Covid vaccination cycle. The issue of safety is then addressed in terms of acceptability of side effects. And “in consideration of the evidence that has just become available, the current absence of specific indications in the Summary of Product Characteristics (Rcp) of the drugs” examined “and the need to allow the vaccination campaign to run smoothly”, the agency’s expert body expresses “a favorable opinion for the inclusion in the list of drugs pursuant to law 648/1996 of Comirnaty and Vaccino Covid-19 Moderna as a second dose to complete a mixed vaccination cycle, in subjects under the age of 60 years who have already carried out a first dose of Vaxzevria vaccine “. Finally, the distinction between the two doses: “On the basis of the CombiVacS study – explains the Cts of Aifa in the opinion – it is believed that the second administration with mRna vaccine can take place 8-12 weeks after the administration of Vaxzevria”.