Sezer Zafer, Pavel Shaikh Terkis Islam, Inal Ahmet, Yetiskin Hazel, Kaplan Busra, Uygut Muhammet Ali, Aslan Ahmet Furkan, Bayram Adnan, Mazicioglu Mumtaz, Kalin Unuvar Gamze, Yuce Zeynep Ture, Aydin Gunsu, Kaya Refika Kamuran, Ates Ihsan, Kara Ates, Ozdarendeli Aykut
Department of Medical Pharmacology, Faculty of Medicine, Erciyes University, Kayseri 38280, Türkiye.
Good Clinical Practise Centre (IKUM), Erciyes University, Kayseri 38280, Türkiye.
Vaccines (Basel). 2024 Jan 29;12(2):140. doi: 10.3390/vaccines12020140.
Vaccine-induced immunity wanes over time and warrants booster doses. We investigated the long-term (32 weeks) immunogenicity and safety of a third, homologous, open-label booster dose of TURKOVAC, administered 12 weeks after completion of the primary series in a randomized, controlled, double-blind, phase 2 study. Forty-two participants included in the analysis were evaluated for neutralizing antibodies (NAbs) (with microneutralization (MNT) and focus reduction (FRNT) tests), SARS-CoV-2 S1 RBD (Spike S1 Receptor Binding Domain), and whole SARS-CoV-2 (with ELISA) IgGs on the day of booster injection and at weeks 1, 2, 4, 8, 16, 24, and 32 thereafter. Antibody titers increased significantly from week 1 and remained higher than the pre-booster titers until at least week 4 (week 8 for whole SARS-CoV-2) ( < 0.05 for all). Seroconversion (titers ≥ 4-fold compared with pre-immune status) persisted 16 weeks (MNT: 6-fold; FRNT: 5.4-fold) for NAbs and 32 weeks for S1 RBD (7.9-fold) and whole SARS-CoV-2 (9.4-fold) IgGs. Nine participants (20.9%) tested positive for SARS-CoV-2 RT-PCR between weeks 8 and 32 of booster vaccination; none of them were hospitalized or died. These findings suggest that boosting with TURKOVAC can provide effective protection against COVID-19 for at least 8 weeks and reduce the severity of the disease.
疫苗诱导的免疫力会随着时间减弱，因此需要接种加强针。我们在一项随机、对照、双盲的2期研究中，调查了在完成初始接种系列12周后给予第三剂同源、开放标签的TURKOVAC加强针的长期（32周）免疫原性和安全性。纳入分析的42名参与者在加强针注射当天以及之后的第1、2、4、8、16、24和32周，接受了中和抗体（NAbs）（采用微量中和试验（MNT）和焦点减少中和试验（FRNT））、SARS-CoV-2 S1受体结合域（Spike S1 Receptor Binding Domain）以及全SARS-CoV-2（采用酶联免疫吸附测定（ELISA））IgG检测。抗体滴度从第1周起显著升高，并至少在第4周（全SARS-CoV-2为第8周）之前一直高于加强针前的滴度（所有比较P<0.05）。NAbs的血清转化率（滴度相比免疫前状态≥4倍）持续16周（MNT：6倍；FRNT：5.4倍），S1 RBD IgG和全SARS-CoV-2 IgG的血清转化率持续32周（分别为7.9倍和9.4倍）。9名参与者（20.9%）在加强针接种后的第8周至32周期间SARS-CoV-2逆转录聚合酶链反应（RT-PCR）检测呈阳性；他们均未住院或死亡。这些发现表明，接种TURKOVAC加强针可提供至少8周的有效新冠病毒防护，并减轻疾病严重程度。
