ABSTRACT
Background: Reduced protection against COVID-19 due to the waning vaccine-induced immunity over time and emergence of immune-evading SARS-CoV-2 variants of concern (VOCs) indicate the need for vaccine boosters. LYB001 is an innovative recombinant SARS-CoV-2 vaccine which displays a repetitive array of the Spike glycoprotein's receptor binding domain (RBD) on a virus-like particle (VLP) vector to boost the immune system, produced using a Covalink plug-and-display protein binding technology. Methods: The safety and immunogenicity of LYB001 as a heterologous booster at an interval of 6-12 months was assessed in 119 participants receiving a booster with (1) 30g LYB001 (I-I-30L) or CoronaVac (I-I-C), (2) escalated dose of 60g LYB001 (I-I-60L) or CoronaVac in a ratio of 2:1 after two-dose primary series of inactivated COVID-19 vaccine in part 1 of this study, or (3) 30g LYB001 (I-I-I-30L) after three-dose primary series of inactivated COVID-19 vaccine in part 2 of this study. Results: A well-tolerated reactogenicity profile was observed for LYB001 as a heterologous booster, with adverse reactions predominantly being mild in severity and transient. The peak neutralizing antibody response was observed at 28 days after booster, with GMT (95%CI) against prototype SARS-CoV-2 being 1237.8 (747.2, 2050.6), 554.3 (374.6, 820.2), 181.9 (107.6, 307.6) and 1200.2 (831.5, 1732.3) in the I-I-30L, I-I-60L, I-I-C, and I-I-I-30L groups, respectively. LYB001 also elicited a cross-neutralizing antibody response against the BA.4/5 strain, dominant during the study period, with GMT being 201.1 (102.7, 393.7), 63.0 (35.1, 113.1), 29.2 (16.9, 50.3) and 115.3 (63.9, 208.1) at 28 days after booster in the I-I-30L, I-I-60L, I-I-C, and I-I-I-30L groups, respectively. Additionally, RBD-specific IFN-{gamma}, IL-2, IL-4 secreting T cells, as measured by ELISpot assay, dramatically increased (more than 10 times versus baseline) at 14 days after a single LYB001 booster. Conclusions: Our data confirm the favorable safety and immunogenicity profile of the LYB001 vaccine when used as a heterologous booster, and support the continued clinical development of this promising candidate that utilize VLP platform to provide protection against COVID-19.
Subject(s)
COVID-19ABSTRACT
The outbreak of coronavirus disease 2019 (COVID-19) has become a rock-ribbed public pandemic and caused substantial health concerns worldwide. In addition to therapeutic strategies, the epidemiologic features and clinical characteristics of patients responded to COVID-19 infection are of equal importance. The study aims to systematically evaluate the clinical presentations and remission of cases with COVID-19 infection in Zunyi, Southwest of China, and to determine the similarities and variations for further clinical classification and comprehensive treatment. Herein, we conducted a retrospective study upon 9 patients in Zunyi, southwest of China, including 1 mild (LPA), 5 severe (SPA) and 3 critical (CPA) types of COVID-19 infection. In details, the demographic data, historical epidemiology, previous medical history, clinical symptoms and complications, laboratory examination, chest imaging, treatment and outcomes of the patients were throughout explored. The non-normal distribution of the data was conducted by utilizing the SPSS software, and significant statistical differences were identified when P < .05. By retrospective analysis of the 9 cases, we found there were multifaceted similarities and differences among them in clinical representation. The patients collectively showed negative for nucleic acid test (NAT) and favorable prognosis after receiving comprehensive therapy such as hormonotherapy, hemopruification, and antiviral administration as well as respiratory support. On the basis of the information, we systematically dissected the clinical features and outcomes of the enrolled patients with COVID-19 and the accompanied multiple syndromes, which would serve as new references for clinical classification and comprehensive treatment. Analysis of clinical characteristics and therapeutic effect of 9 cases of novel coronavirus pneumonia (COVID-19), ChiCTR2000031930. Registered April 15, 2020 (retrospective registration).