@article {6684, title = {Immunogenicity of SARS-CoV-2 vaccines BBV152 (COVAXIN{\textregistered}) and ChAdOx1 nCoV-19 (COVISHIELD{\texttrademark}) in seronegative and seropositive individuals in India: a multicentre, nonrandomised observational study.}, journal = {Lancet Reg Health Southeast Asia}, volume = {22}, year = {2024}, month = {2024 Mar}, pages = {100361}, abstract = {

BACKGROUND: There are limited global data on head-to-head comparisons of vaccine platforms assessing both humoral and cellular immune responses, stratified by pre-vaccination serostatus. The COVID-19 vaccination drive for the Indian population in the age group 18-45 years began in April 2021 when seropositivity rates in the general population were rising due to the delta wave of COVID-19 pandemic during April-May\ 2021.

METHODS: Between June 30, 2021, and Jan 28, 2022, we enrolled 691 participants in the age group 18-45 years across four clinical sites in India. In this non-randomised and laboratory blinded study, participants received either two doses of Covaxin{\textregistered} (4 weeks apart) or two doses of Covishield{\texttrademark} (12 weeks apart) as per the national vaccination policy. The primary outcome was the seroconversion rate and the geometric mean titre (GMT) of antibodies against the SARS-CoV-2 spike and nucleocapsid proteins post two doses. The secondary outcome was the frequency of cellular immune responses pre- and post-vaccination.

FINDINGS: When compared to pre-vaccination baseline, both vaccines elicited statistically significant seroconversion and binding antibody levels in both seronegative and seropositive individuals. In the per-protocol cohort, Covishield{\texttrademark} elicited higher antibody responses than Covaxin{\textregistered} as measured by seroconversion rate (98.3\% vs 74.4\%, p\ \<\ 0.0001 in seronegative individuals; 91.7\% vs 66.9\%, p\ \<\ 0.0001 in seropositive individuals) as well as by anti-spike antibody levels against the ancestral strain (GMT 1272.1 vs 75.4 binding antibody units/ml [BAU/ml], p\ \<\ 0.0001 in seronegative individuals; 2089.07 vs 585.7 BAU/ml, p\ \<\ 0.0001 in seropositive individuals). As participants at all clinical sites were not recruited at the same time, site-specific immunogenicity was impacted by the timing of vaccination relative to the delta and omicron waves. Surrogate neutralising antibody responses against variants-of-concern including delta and omicron was higher in Covishield{\texttrademark} recipients than in Covaxin{\textregistered} recipients; and in seropositive than in seronegative individuals after both vaccination and asymptomatic infection (omicron variant). T cell responses are reported from only one of the four site cohorts where the vaccination schedule preceded the omicron wave. In seronegative individuals, Covishield{\texttrademark} elicited both CD4+ and CD8+ spike-specific cytokine-producing T cells whereas Covaxin{\textregistered} elicited mainly CD4+ spike-specific T cells. Neither vaccine showed significant post-vaccination expansion of spike-specific T cells in seropositive individuals.

INTERPRETATION: Covishield{\texttrademark} elicited immune responses of higher magnitude and breadth than Covaxin{\textregistered} in both seronegative individuals and seropositive individuals, across cohorts representing the pre-vaccination immune history of most of the vaccinated Indian population.

FUNDING: Corporate social responsibility (CSR) funding from Hindustan Unilever Limited (HUL) and Unilever India Pvt. Ltd. (UIPL).

}, issn = {2772-3682}, doi = {10.1016/j.lansea.2024.100361}, author = {Asokan, Mangaiarkarasi S and Joan, Roshni Florina and Babji, Sudhir and Dayma, Girish and Nadukkandy, Prajitha and Subrahmanyam, Vinutha and Pandey, Archana and Malagi, Girish and Arya, Pooja and Mahajan, Vibhuti and Bhavikatti, Jayateerth and Pawar, Ketakee and Thorat, Aishwarya and Shah, Priyanki and Goud, Ramakrishna B and Roy, Bishnudeo and Rajukutty, Shon and Immanuel, Sushil and Agarwal, Dhiraj and Saha, Sankhanil and Shivaraj, Akshatha and Panikulam, Patricia and Shome, Rajeshwari and Gulzar, Shah-E-Jahan and Sharma, Anusmrithi U and Naik, Ajinkya and Talashi, Shruti and Belekar, Madhuri and Yadav, Ritu and Khude, Poornima and V, Mamatha and Shivalingaiah, Sudarshan and Deshmukh, Urmila and Bhise, Chinmayee and Joshi, Manjiri and Inbaraj, Leeberk Raja and Chandrasingh, Sindhulina and Ghose, Aurnab and Jamora, Colin and Karumbati, Anandi S and Sundaramurthy, Varadharajan and Johnson, Avita and Ramesh, Naveen and Chetan, Nirutha and Parthiban, Chaitra and Ahmed, Asma and Rakshit, Srabanti and Adiga, Vasista and D{\textquoteright}souza, George and Rale, Vinay and George, Carolin Elizabeth and John, Jacob and Kawade, Anand and Chaturvedi, Akanksha and Raghunathan, Anu and Dias, Mary and Bhosale, Anand and Raghu, Padinjat and Shashidhara, L S and Vyakarnam, Annapurna and Bal, Vineeta and Kang, Gagandeep and Mayor, Satyajit} }