The US Centers for Disease Control and Prevention (CDC) now recommends that unvaccinated Americans should receive an mRNA vaccine in preference to Johnson & Johnson’s (J&J) single-dose vaccine.
The updated CDC advice follows a unanimous vote from its Advisory Committee on Immunization Practices (ACIP) which involved ‘a robust discussion of the latest evidence on vaccine effectiveness, vaccine safety and rare adverse events, and consideration of the US vaccine supply’.
The recommendation from ACIP comes after the body was shown new data on the incidence of the blood-clotting condition, thrombocytopenia syndrome (TTS).
In the US, covering the period to the end of August 2021, 54 cases of TTS were identified following the J&J vaccine, while in data extending to December, 9 deaths have now been reported in the US. The highest rates of the condition were seen among women in their 30s and 40s.
The updated advice follows similar recommendations from other countries, including Canada and the United Kingdom, stressed the CDC. Individuals who are unable or unwilling to receive an mRNA vaccine will continue to have access to Johnson & Johnson’s COVID-19 vaccine.
J&J responded to these safety concerns by reasserting its confidence in the efficacy of its vaccine. It said ‘remains confident’ in its overall positive benefit-risk profile, stating the vaccine ‘generates strong antibody and cellular immune responses and long-lasting immune memory’. It added that ‘a growing body of evidence’ shows ‘the strength of protection of our vaccine as a booster’, both in terms of its efficacy and durability.
“The safety and well-being of those who use the Johnson & Johnson vaccine continues to be our number one priority,” says Dr Mathai Mammen head of R&D at Janssen. “We appreciate today’s discussion and look forward to working with the CDC on next steps. In addition, we strongly support education and generating awareness of rare events, such as thrombosis with thrombocytopenia syndrome and how to effectively manage it.”
However, while CDC director Dr. Rochelle Walensky continues to urge Americans to get vaccinated, the focus of much of the world is increasingly moving to vaccines that have been adapted to combat the new variant of concern.
In a matter of a fortnight, the Omicron variant has swept from southern Africa to every other continent. In Europe, London remains the epicentre, with its mayor declaring a “major incident” as COVID-19 cases explode, rising 500% among young people in just a week. In the US, New York set new records for cases on both Friday and Saturday, although the variant is now in nearly every State.
Even though a vaccine adapted to the new variant is months away, the European Union has exercised its option to buy more than 180 million doses of the Pfizer-BioNTech vaccine.
Announcing the deal, head of the European Commission, Ursula von der Leyen, said deliveries would start in the second quarter of the year. However, the news seems to have caught Pfizer off-guard which said its talks with the EU had not so far concerned adapted versions of the vaccine.
“While we believe we can deliver an adapted vaccine in March 2022, we do not yet know whether this will be needed and availability will require authorisation by regulatory authorities,” said Pfizer.