Samoud Samar, Bettaieb Jihene, Gdoura Mariem, Kharroubi Ghassen, Ben Ghachem Feriel, Zamali Imen, Ben Hmid Ahlem, Salem Sadok, Gereisha Ahmed Adel, Dellagi Mongi, Hogga Nahed, Gharbi Adel, Baccouche Amor, Gharbi Manel, Khemissi Chadha, Akili Ghada, Slama Wissem, Chaieb Nabila, Galai Yousr, Louzir Hechmi, Triki Henda, Ben Ahmed Melika
Department of Clinical Immunology, Pasteur Institute of Tunis, Tunis 1002, Tunisia.
Faculty of Medicine of Sousse, University of Sousse, Sousse 4000, Tunisia.
Vaccines (Basel). 2023 Aug 5;11(8):1329. doi: 10.3390/vaccines11081329.
(1) Background: This study aimed to compare the immunogenicity of the mix-and-match CoronaVac/BNT162b2 vaccination to the homologous CoronaVac/CoronaVac regimen. (2) Methods: We conducted a simple-blinded randomized superiority trial to measure SARS-CoV-2 neutralization antibodies and anti-spike receptor binding domain (RBD) IgG concentrations in blood samples of participants who had received the first dose of CoronaVac vaccine followed by a dose of BNT162b2 or CoronaVac vaccine. The primary endpoint for immunogenicity was the serum-neutralizing antibody level with a percentage of inhibition at 90% at 21-35 days after the boost. A difference of 25% between groups was considered clinically relevant. (3) Results: Among the 240 eligible participants, the primary endpoint data were available for 100 participants randomly allocated to the mix-and-match group versus 99 participants randomly allocated to the homologous dose group. The mix-and-match regimen elicited significantly higher levels of neutralizing antibodies (median level of 96%, interquartile range (IQR) (95-97) versus median level of 94%, IQR (81-96) and anti-spike IgG antibodies (median level of 13,460, IQR (2557-29,930) versus median level of 1190, IQR (347-4964) compared to the homologous group. Accordingly, the percentage of subjects with a percentage of neutralizing antibodies > 90% was significantly higher in the mix-and-match group (90.0%) versus the homologous (60.6%). Interestingly, no severe events were reported within 30 days after the second dose of vaccination in both groups. (4) Conclusions: Our data showed the superiority of the mix-and-match CoronaVac/BNT162b2 vaccination compared to the CoronaVac/CoronaVac regimen in terms of immunogenicity, thus constituting a proof-of-concept study supporting the use of inactivated vaccines in a mix-and-match strategy while ensuring good immunogenicity and safety.
(1) 背景：本研究旨在比较混合接种科兴疫苗（CoronaVac）/BNT162b2疫苗与同源接种科兴疫苗/科兴疫苗方案的免疫原性。(2) 方法：我们进行了一项单盲随机优效性试验，以测量在接受第一剂科兴疫苗后，再接种一剂BNT162b2疫苗或科兴疫苗的参与者血液样本中SARS-CoV-2中和抗体及抗刺突受体结合域（RBD）IgG浓度。免疫原性的主要终点是加强免疫后21至35天血清中和抗体水平，抑制率达90%。两组间差异达25%被认为具有临床相关性。(3) 结果：在240名符合条件的参与者中，100名随机分配到混合接种组的参与者和99名随机分配到同源接种组的参与者可获得主要终点数据。与同源接种组相比，混合接种方案诱导产生的中和抗体水平显著更高（中位数水平为96%，四分位间距（IQR）为(95 - 97)，而同源接种组中位数水平为94%，IQR为(81 - 96)），抗刺突IgG抗体水平也更高（中位数水平为13460，IQR为(2557 - 29930)，而同源接种组中位数水平为1190，IQR为(347 - 4964)）。因此，中和抗体百分比>90%的受试者比例在混合接种组（90.0%）显著高于同源接种组（60.6%）。有趣的是，两组在第二剂疫苗接种后30天内均未报告严重事件。(4) 结论：我们的数据显示，在免疫原性方面，混合接种科兴疫苗/BNT162b2疫苗优于同源接种科兴疫苗/科兴疫苗方案，从而构成了一项概念验证研究，支持在混合接种策略中使用灭活疫苗，同时确保良好的免疫原性和安全性。
