Ates Ihsan, Batirel Ayse, Aydin Mehtap, Karadag Fatma Yilmaz, Erden Abdulsamet, Kucuksahin Orhan, Armagan Berkan, Guven Serdar Can, Karakas Ozlem, Gokdemir Selim, Altunal Lutfiye Nilsun, Buber Aslihan Ayse, Gemcioglu Emin, Zengin Oguzhan, Inan Osman, Sahiner Enes Seyda, Korukluoglu Gulay, Sezer Zafer, Ozdarendeli Aykut, Omma Ahmet, Kara Ates
Department of Internal Medicine, University of Health Sciences, Ankara City Hospital, 06800 Ankara, Türkiye.
Department of Infectious Diseases and Clinical Microbiology, University of Health Sciences, International Medical School, Kartal Dr. Lutfi Kirdar City Hospital, 34865 Istanbul, Türkiye.
Vaccines (Basel). 2023 Jul 12;11(7):1234. doi: 10.3390/vaccines11071234.
The immunogenicity of vaccines decreases over time, causing a need for booster doses. This study aimed to present the long-term (Day 84) immunogenicity results of the double-blind, randomized, controlled, phase II Hybrid COV-RAPEL TR Study (NCT04979949), in which the TURKOVAC or CoronaVac vaccines were used as a booster after the second dose of primary vaccination with CoronaVac. A total of 190 participants from the Hybrid COV-RAPEL TR Study, who had both Day 28 and Day 84 immunogenicity results, were included. The immunogenicity on Day 84, regarding the neutralizing antibody positivity (Wuhan and Delta variants) and anti-spike immunoglobulin (Ig) G (IgG) antibody positivity, was compared between TURKOVAC and CoronaVac vaccine arms according to sex and age groups. Overall, antibody positivity showed a slight decrease on Day 84 vs. Day 28, but was not different between TURKOVAC and CoronaVac arms either for sexes or for age groups. However, TURKOVAC produced better antibody response against the Delta variant than CoronaVac, while CoronaVac was superior over TURKOVAC regarding neutralizing antibody positivity in the 50-60 years age group, regardless of the variant. A single booster dose, after the completion of the primary vaccination, increases antibody positivity on Day 28 which persists until Day 84 with a slight decrease. However, an additional booster dose may be required thereafter, since the decrease in antibody titer may be faster over time.
疫苗的免疫原性会随着时间下降，因此需要加强剂量。本研究旨在呈现双盲、随机、对照的II期Hybrid COV-RAPEL TR研究（NCT04979949）的长期（第84天）免疫原性结果，该研究中在第二次接种科兴疫苗进行基础免疫后，使用TURKOVAC或科兴疫苗作为加强针。共有190名来自Hybrid COV-RAPEL TR研究的参与者被纳入，他们同时拥有第28天和第84天的免疫原性结果。根据性别和年龄组，比较了TURKOVAC和科兴疫苗组在第84天关于中和抗体阳性（武汉和德尔塔变体）和抗刺突免疫球蛋白（Ig）G（IgG）抗体阳性的免疫原性。总体而言，与第28天相比，第84天抗体阳性率略有下降，但TURKOVAC和科兴疫苗组在性别或年龄组方面均无差异。然而，TURKOVAC对德尔塔变体产生的抗体反应比科兴疫苗更好，而在50-60岁年龄组中，无论变体如何，科兴疫苗在中和抗体阳性方面优于TURKOVAC。在完成基础免疫后接种一剂加强针，可使第28天的抗体阳性率增加，并持续至第84天，略有下降。然而，此后可能需要额外的加强针，因为抗体滴度可能会随着时间更快地下降。
