Launch of first single-dose Covid-19 vaccine followed by an intense week for EU’s safety monitoring plan for Covid vaccines

The European Commission has granted conditional marketing authorisation (CMA) for the Covid-19 vaccine developed by Janssen (a J&J company). 

The authorisation of this, the fourth Covid-19 vaccine in the EU, was granted just ahead of a pause in the use of Covid-19 Vaccine AstraZeneca in Ireland and several other countries while concerns about cases of thrombosis and thrombocytopenia following vaccination were investigated. Ireland’s Health Protection Regulatory Authority (HPRA) participated in this scientific and evidence-based review through its membership of the European Medicines Agency’s safety committee, PRAC.

Following PRAC’s preliminary review, the EMA said the benefit-risk balance of Covid-19 Vaccine AstraZeneca remains positive, and found no association with thromboembolic disorders overall. However, the HPRA said the summary of product characteristics (SmPC) and package leaflet will be updated with information on very rare cases of disseminated intravascular coagulation (DIC) and cerebral venous sinus thrombosis (CVST), of which seven and 18 cases respectively had been reported as of March 16, 2021.

The HPRA urges healthcare professionals to be alert for possible cases of thromboembolism, DIC or CVST occurring in vaccinated individuals. Recipients should be warned to seek immediate medical attention for symptoms of thromboembolism, and especially signs of thrombocytopenia and cerebral blood clots such as easy bruising or bleeding, and persistent or severe headache, particularly beyond three days after vaccination.

Covid-19 Vaccine Janssen 

Meanwhile, the authorisation of the single-dose Covid-19 Vaccine Janssen followed a positive scientific recommendation based on a thorough assessment of the safety, effectiveness and quality of the vaccine by the EMA and is endorsed by the EU member states. Covid-19 Vaccine Janssen is made up of an adenovirus that has been modified to contain the gene for making the SARS-CoV-2 spike protein. 

Results from the randomised, double-blind, placebo-controlled phase III ENSEMBLE clinical trial study involving over 44,000 people in the US, South Africa and Latin American countries, found that Covid-19 Vaccine Janssen was effective at preventing Covid-19 in people ≥ 18 years. The study was designed to evaluate the safety and efficacy of a single dose of a vaccine versus placebo in up to 60,000 adults ≥ 18 years, including significant representation from those > 60 years. 

The trial found a 67% reduction in the number of symptomatic Covid-19 cases after two weeks in participants who received Covid-19 Vaccine Janssen (116 cases out of 19,630 people) compared with placebo (348 of 19,691 people). This means that the vaccine had a 67% efficacy. The onset of protection was observed from day 14 and was maintained 28 days post-vaccination. The data also demonstrated the vaccine was 85% effective in preventing severe disease, and showed protection against Covid-19 related hospitalisation and death, beginning 28 days after vaccination. The side effects with Covid-19 Vaccine Janssen were usually mild or moderate and cleared within a couple of days of vaccination. The most common were pain at the injection site, headache, tiredness, muscle pain and nausea. 

In line with the EU’s safety monitoring plan for Covid-19 vaccines, Covid-19 Vaccine Janssen will be subject to several activities that apply specifically to Covid-19 vaccines. Companies are required to provide monthly safety reports in addition to the regular updates required by legislation and conduct studies to monitor the safety and effectiveness of the vaccines as they are used.

Review of antibodies in treatment of Covid-19

The European Medicines Agency’s Committee for Medicinal Products for Human Use (CHMP) has issued a positive scientific opinion for bamlanivimab alone and bamlanivimab administered together with etesevimab. The opinion advises bamlanivimab alone and bamlanivimab plus etesevimab can be used for the treatment of confirmed Covid-19 in patients aged 12 years and older who do not require supplemental oxygen for Covid-19 and who are at high risk of progressing to severe Covid-19. 

The CHMP scientific opinion provides a harmonised, EU-level opinion on the efficacy, quality and safety of the antibodies. The opinion can now be considered by the EU member states when making decisions on the use of the therapies at a national level before a formal EU marketing authorisation is issued.

To support the opinion, the EMA reviewed phase II and phase III results from Lilly’s BLAZE-1 trial. Results from BLAZE-1 demonstrated bamlanivimab alone reduced viral load and symptoms and also reduced Covid-19 hospitalisations by approximately 70%, and bamlanivimab and etesevimab together reduced the risk of Covid-19 hospitalisations and death by 70% in non-hospitalised high-risk patients with mild to moderate Covid-19.