Safety and immunogenicity of a modified COVID-19 mRNA vaccine, SW-BIC-213, as a heterologous booster in healthy adults: an open-labeled, two-centered and multi-arm randomised, phase 1 trial

• DOI: 10.1016/j.ebiom.2023.104586
• Publication Date: 2023-04-24T21:50:30Z
• Authors: Yu-Zhou Gui; Xue-Ning Li; Jing-Xin Li; Ming-Yun Shen; Mei-Wei Zhang; Ye Cao; Hong-Rong Xu; Hui Li; Jie Cheng; Liang Pan; Ying-Lei Yi; Li-Yu Liang; Cheng-Yin Yu; Gang-Yi Liu; Chen Yu; Bi-Jie Hu; Feng-Cai Zhu; Fei Liang; Haifa Shen; Jing-Ying Jia; Hang-Wen Li; Jian Zhou; Jia Fan
• Keywords: Adult; Medicine (General); China; COVID-19 Vaccines; SARS-CoV-2; R; COVID-19; Articles; 16. Peace & justice; Antibodies, Viral; Antibodies, Neutralizing; 3. Good health; Clinical trial; mRNA vaccine; R5-920; Heterologous boosting; Double-Blind Method; Medicine; Humans; mRNA Vaccines

We assessed the safety and immunogenicity of a core-shell structured lipopolyplex (LPP) based COVID-19 mRNA vaccine, SW-BIC-213, as a heterologous booster in healthy adults.We conducted an open-labeled, two-centered, and three-arm randomised phase 1 trial. Healthy adults, who had completed a two-dose of inactivated COVID-19 vaccine for more than six months, were enrolled and randomized to receive a booster dose of COVILO (inactivated vaccine) (n = 20) or SW-BIC-213-25μg (n = 20), or SW-BIC-213-45μg (n = 20). The primary study endpoint was adverse events within 30 days post-boosting. The secondary endpoint was the titers of binding antibodies and neutralizing antibodies against the wild-type (WT) of SARS-CoV-2 as well as variants of concern in serum. The exploratory endpoint was the cellular immune responses. This trial was registered with http://www.chictr.org.cn (ChiCTR2200060355).Between Jun 6 and Jun 22, 2022, 60 participants were enrolled and randomized to receive a booster dose of SW-BIC-213 (25 μg, n = 20, or 45 μg, n = 20) or COVILO (n = 20). The baseline demographic characteristics of the participants at enrollment were similar among the treatment groups. For the primary outcome, injection site pain and fever were more common in the SW-BIC-213 groups (25 μg and 45 μg). Grade 3 fever was reported in 25% (5/20) of participants in the SW-BIC-213-45μg group but was resolved within 48 h after onset. No fatal events or adverse events leading to study discontinuation were observed. For secondary and exploratory outcomes, SW-BIC-213 elicited higher and longer humoral and cellular immune responses than that in the COVILO group.SW-BIC-213, a core-shell structured lipopolyplex (LPP) based mRNA vaccine, was safe, tolerable, and immunogenic as a heterologous booster in healthy Chinese adults.Shanghai Municipal Government, the Science and Technology and Economic Commission of Shanghai Pudong New Area, and mRNA Innovation and Translation Center of Shanghai.