The Lancet: Scientists Release Results of Human Phase 3 Interim Clinical Trials of COVID-19 Vaccine: ChAdOx1 Vaccine May Show Acceptable Safety and Efficacy!

December 11, 2020 // -- A recent article published in the international magazine The Lancet entitled "Safety and efficacy of the chAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: anterim analysis of four randomized controled trials in Brazil, In the South Africa, and the UK" study, scientists from Oxford University and others published the results of phase 3 clinical trials of the COVID-19 Oxford vaccine, which showed that a new vaccine called ChaAdOx1 nCoV-19 is acceptablely safe and effective against patients with symptoms of COVID-19 in clinical trials.
study, published recently, researchers used South African data to assess the safety of the vaccine, but not its therapeutic efficacy (a percentage reduction in disease).
researcher Shabir Madhi said the data from South Africa were not included in the analysis of patients' comprehensive efficacy because there were very few cases of COVID-19 in South Africa after at least 14 days of receiving the second dose of the vaccine.
this study heralds a milestone in the development of the COVDI-19 vaccine, and the results have passed rigorous scientific peer review for the scientific community and the public to inquire about.
photo source: factly.in, the researchers presented the results of a Phase 3 clinical trial analysis of the new vaccine against SARS-CoV-2 under two different dose options, which resulted in an average efficacy of 70.4 percent for the volunteers.
The results were based on 11,636 volunteers from the UK and Brazil, and also combined data from three groups of people who received the standard dose of the first dose of the vaccine, followed by a standard dose of the enhanced vaccine, and another group (in the UK only) received a low dose of the first dose of the vaccine, followed by a standard dose of the vaccine.
addition, the vaccine was evaluated in 2,100 South African populations, who are still being followed by researchers on COVID-19 before evaluating its efficacy.
and peer-reviewed data further showed that there were no hospitalizations or serious illnesses in the vaccination group.
Compared to the mRNA vaccine, the future deployment of this new COVID-19 vaccine in low- and middle-income countries is highly prospect, requires only moderate refrigeration and is read easily available, as its production capacity is easily expanded, and is likely to be the most affordable of the three COVID-19 vaccines that have been reported to be safe and effective.
Researcher Professor Andrew Pollard said: 'We have published the results of an interim analysis of phase 3 trials and demonstrated that the new vaccine has a good safety record and efficacy. After a comprehensive analysis of
, the researchers noted that the overall vaccine was 70.4% effective at least 14 days after the second dose of the vaccine, while the standard dose/standard dose subgroup showed 62.1% efficacy, while the low/standard dose subgroup achieved 90.0% efficacy, and no hospitalization or serious illness was observed in the vaccination group.
researchers noted that 170 of the 24,103 volunteers and 73,480 "person-month" safety follow-ups reported serious adverse events, three of which may have been related to vaccination.
one of the volunteers was thought to be likely to be associated with the ChAdOx1 nCoV-19 vaccination, one volunteer from the control group and the other from the vaccination group had severe fever, which was considered to be the expected vaccination-related event.
In addition, the researchers reported two updates to the trial programme in this study, namely, the modification of the planned single-dose study to a two-dose study after early immunogenicity results appeared, and the addition of low-dose/standard-dose vaccination programmes after differences in the quantitative method results of different batches of vaccines were observed.
Of the 11,636 volunteers from the UK and Brazil who were initially initially analysed for efficacy, the majority were aged between 18 and 55 (87 per cent of British volunteers and 90 per cent of Brazilian volunteers), with 12 per cent over the age of 56.
Since only five of the volunteers included in the preliminary analysis were over 55 years of age, the researchers were unable to assess the efficacy of the vaccine in the older population, but the relevant analysis could be carried out in the future after the volunteers in that age group had accumulated more cases.
researchers also investigated the vaccine's potential to prevent asymptomatic diseases by using weekly swabs from British trial volunteers.
The results suggest that low-dose/standard-dose vaccines may provide protection against asymptomatic infections, but stress that these data are at an early stage and the uncertainty is too high for researchers to determine whether the vaccine protects the body from asymptomatic infections.
researchers are currently analyzing the data further, and they will provide it to regulators to best determine the dose option if the vaccine is authorized for emergency use. Madhi, a
researcher, said the South African government must be proactive in seeking all options to ensure early access to a large number of COVID-19 vaccines at affordable prices, ideally in advance of a large-scale recovery of the COVID-19 outbreak.
() Original source: Merryn Voysey D Phil, Sue Ann Costa Clemens, Shabir A Madhi, et al. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK, The Lancet (2020) doi:10.1016/S0140-6736(20)32661-1。