Thursday, September 15, 2022
Researchers from the Millennium Institute in Immunology and Immunotherapy (IMII) will lead the scientific-clinical study that the Pontifical Catholic University of Chile (UC) will carry out from the end of October, in order to evaluate the immune response capacity of new Sinovac vaccines against SARS-CoV-2 -the virus that causes COVID-19- that are aimed at combating circulating variants.
Currently, Ómicron is the variant that dominates SARS-CoV-2 infections in much of the world, including Chile, which to date exceeds 4.5 million positive cases of COVID-19 registered by the Ministry of Health . Dr. Pablo González, associate researcher at the IMII and academic at the UC Faculty of Biological Sciences, will lead the study, which was approved by the Institute of Public Health a few days ago.
“In the study, a new booster dose will be administered to adults of both sexes and from the age of 18 who have previously received two booster doses with different inoculation schemes.that is, people who have received the first two doses of CoronaVac, from the Chinese laboratory Sinovac, and then two booster doses, either with the same or different characteristics, such as a messenger RNA-based vaccine or another type of platform, ”explains the PhD in molecular genetics and microbiology.
People will be enrolled through registrations on the website www.vacunavariantescovid.cl. González indicates that those who have had a symptomatic infection with SARS-CoV-2 in the sixty days prior to joining the study will be able to participate in this study, which in total will enroll a little more than 800 volunteers.
Like the CoronaVac vaccine that is currently administered, the three immunizers studied consist of inactivated virus, that is, non-infectious virus that is presented to the body’s immune system. Among the three vaccines to be evaluated in the study, one is formulated based on the Omicron variant; another is trivalent and is made up of inactivated viruses of the Delta and Omicron variants, as well as the ancestral strain; and the third consists of the ancestral strain (similar to CoronaVac).
The study will evaluate the ability of antibodies to neutralize different variants of SARS-CoV-2 in the serum of people. “An evaluation of the induced response will be made a month later and another six months after the inoculation has been carried out,” says Dr. González.
Dr. Alexis Kalergis, director of the IMII and UC academic, points out that the study that will start at the end of next month will be the first of Sinovac in the world to evaluate the immunogenicity of these new vaccines, that is, its ability to generate an immune response. “This study against variants of SARS-CoV-2 is pioneering and will allow the evaluation of vaccines that are more adapted to the circulating virus with great possibilities of provoking a more protective immune response against different variants of SARS-CoV-2.” Likewise, the scientist indicates that “this study will allow us to know firsthand the type of immune response induced by new vaccines against COVID-19, adapted to circulating viruses.”
The researcher highlights that the study and what the UC and the IMII are doing regarding vaccines against the virus that causes COVID-19, “is based on previous studies that we have done at UC, with results that have been openly disseminated in numerous publications and that have served for decision-making at the public health level. This has involved reaching different pediatric and adult populations, thus helping to limit the pandemic and so that we can learn more about this virus in the short and medium term.”
The IMII at UC continues to develop a Chilean-created vaccine against SARS-CoV-2, “that can be applied from birth and based on a secure platform,” explains Kalergis. This work, led by Dr. Alexis Kalergis, has so far involved the generation of prototype vaccines aimed at inducing immunity against the new coronavirus.