According to The Lancet, Phase 2 leads to the conclusion that the antidote causes “few side effects” and “induces an immune response in both parts of the immune system in all age groups”
The second stage from clinic tests of the vaccine against him COVID-19 developed by the English University of Oxford shows that it is safe in older adults healthy and causes a immune response, reports this Thursday the medical journal The Lancet.
In collaboration with the pharmacist AstraZeneca and other agencies, the researchers tested the preparation, called ChAdOx1 nCoV-19, in an experiment with 560 healthy adults, including 240 over 70, with the aim of observing its impact on the immune system and possible side effects.
The “promising preliminary results” indicated that this vaccine against the virus SARS-CoV-2 it offers “similar safety and immunogenicity results in healthy older adults than in those between 18 and 55 years old.”
According to The Lancet, Phase 2 allows us to conclude that the antidote causes “few side effects” and “induces an immune response in both parts of the immune system in all age groups with both a low and standard dose”.
According to the study, the British vaccine generates a T-cell response (capable of finding and attacking cells infected by the virus) 14 days after the first dose, and an antibody response 28 days after the dose of booster (that would attack the virus when circulating through the blood or lymphatic system).
The authors noted that Phase 3 of the clinical trials, which is underway, should confirm these results and determine “to what extent the vaccine is effective in protecting against SARS-CoV-2 infection” in a larger and more heterogeneous group. of people, which includes elderly people with previous pathologies.
In the study released today, which does not measure the effectiveness of the vaccine to protect from the virus, 560 adults (160 between 18 and 55 years old; 160 between 56 and 59 years old and 240 over 70) in good health received the vaccine well Oxford’s well an antidote to control.
Volunteers over 55 years of age were divided into two groups and received a single dose of the vaccine or two in a 28-day period.
All were observed from the beginning to detect adverse effects as well as the immune response.
The authors noted that the side effects of ChAdOx1 nCoV-19 were “mild” (such as injection pain, fatigue, headache, fever, or muscle pain) although more common than with the control vaccine.
Thirteen serious cases were detected in the six months from the first dose but they are not considered related to vaccines.
The researchers explained that side effects were even less common in older adults than younger ones, and the immune response was “similar” in all age groups after the booster dose.
The vaccine induced antibodies against the coronavirus spike protein 28 days after a first low or standard dose in all age groups. After the booster vaccination, the antibody level increased 56 days after the start of the experiment, and the same happened with the neutralizing antibodies 42 days later.
For its part, the response of the T cells against the coronavirus tip protein culminated fourteen days after the first inoculation, regardless of age or dose.
The researcher Sarah Gilbert stated that this study “answers some of the questions” raised by the World Health Organization (who) on the need for covid vaccines to protect older adults.
However, he pointed out, other “questions about the efficacy and duration of protection” remain to be answered and the vaccine should also be tested in older people with pathologies to ensure that it protects those who are most at risk of becoming seriously ill.
The authors acknowledged that their experiment “has limitations”, for example that the oldest people had an average age of 73 or 74 years and were healthy, which does not reflect the situation in nursing homes.
In addition, they added, the majority of volunteers of any age were white and non-smokers, so in the third phase of clinical trials, the tests will be extended to people of different backgrounds.
With information from .