Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 4 de 4
Add filters

Document Type
Year range
medrxiv; 2022.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2022.09.05.22279589


BACKGROUNDThe rising breakthrough infections caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, especially Omicron and its sub-lineages, have raised an urgent need to develop broad-spectrum vaccines against coronavirus disease 2019 (COVID-19). We have developed a mosaic-type recombinant vaccine candidate, named NVSI-06-09, having immune potentials against a broad range of SARS-CoV-2 variants. METHODSAn ongoing randomized, double-blind, controlled phase 2 trial was conducted to evaluate the safety and immunogenicity of NVSI-06-09 as a booster dose in subjects aged 18 years and older from the United Arab Emirates (UAE), who had completed two or three doses of BBIBP-CorV vaccinations at least 6 months prior to the enrollment. The participants were randomly assigned with 1:1 to receive a booster dose of NVSI-06-09 or BBIBP-CorV. The primary outcomes were immunogenicity and safety against SARS-CoV-2 Omicron variant, and the exploratory outcome was cross-immunogenicity against other circulating strains. RESULTSA total of 516 participants received booster vaccination. Interim results showed a similar safety profile between NVSI-06-09 and BBIBP-CorV booster groups, with low incidence of adverse reactions of grade 1 or 2. For immunogenicity, by day 14 after the booster vaccination, the fold rises in neutralizing antibody geometric mean titers (GMTs) from baseline level elicited by NVSI-06-09 were remarkably higher than those by BBIBP-CorV against the prototype strain (19.67 vs 4.47-fold), Omicron BA.1.1 (42.35 vs 3.78-fold), BA.2 (25.09 vs 2.91-fold), BA.4 (22.42 vs 2.69-fold), and BA.5 variants (27.06 vs 4.73-fold). Similarly, the neutralizing GMTs boosted by NVSI-06-09 against Beta and Delta variants were also 6.60-fold and 7.17-fold higher than those boosted by BBIBP-CorV. CONCLUSIONSA booster dose of NVSI-06-09 was well-tolerated and elicited broad-spectrum neutralizing responses against SARS-CoV-2 prototype strain and immune-evasive variants, including Omicron and its sub-lineages. The immunogenicity of NVSI-06-09 as a booster vaccine was superior to that of BBIBP-CorV. (Funded by LIBP and BIBP of Sinopharm; number, NCT05293548).

Coronavirus Infections , Breakthrough Pain , COVID-19
medrxiv; 2022.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2022.03.08.22272062


The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with immune escape ability raises the urgent need for developing cross-neutralizing vaccines against the virus. NVSI-06-08 is a potential broad-spectrum recombinant COVID-19 vaccine that integrates the antigens from multiple SARS-CoV-2 strains into a single immunogen. Here, we evaluated the safety and immunogenicity of NVSI-06-08 as a heterologous booster dose in adults previously vaccinated with the inactivated vaccine BBIBP-CorV in a randomized, double-blind, controlled, phase 2 trial conducted in the United Arab Emirates (NCT05069129). Three groups of healthy adults over 18 years of age (600 participants per group) who had administered two doses of BBIBP-CorV 4-6-month, 7-9-month and >9-month earlier, respectively, were vaccinated with either a homologous booster of BBIBP-CorV or a heterologous booster of NVSI-06-08. The primary outcome was immunogenicity and safety of booster vaccinations. The exploratory outcome was cross-reactive immunogenicity against multiple SARS-CoV-2 variants of concerns (VOCs). The incidence of adverse reactions was low in both booster vaccinations, and the overall safety profile of heterologous boost was quite similar to that of homologous boost. Heterologous NVSI-06-08 booster was immunogenically superior to homologous booster of BBIBP-CorV. Both Neutralizing and IgG antibodies elicited by NVSI-06-08 booster were significantly higher than by the booster of BBIBP-CorV against not only SARS-CoV-2 prototype strain but also multiple VOCs. Especially, the neutralizing activity induced by NVSI-06-08 booster against the immune-evasive Beta variant was no less than that against the prototype strain, and a considerable level of neutralizing antibodies against Omicron (GMT: 367.67; 95%CI, 295.50-457.47) was induced by heterologous booster, which was substantially higher than that boosted by BBIBP-CorV (GMT: 45.03; 95%CI, 36.37-55.74). Our findings showed that NVSI-06-08 was safe and immunogenic as a booster dose following two doses of BBIBP-CorV, which was immunogenically superior to homologous boost with another dose of BBIBP-CorV. Our study also indicated that the design of hybrid antigen may provide an effective strategy for broad-spectrum vaccine developments.

Coronavirus Infections , COVID-19
medrxiv; 2022.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.12.29.21268499


Background: The increased coronavirus disease 2019 (COVID-19) breakthrough cases pose the need of booster vaccinations. In this study, we reported the safety and immunogenicity of a heterologous boost with a recombinant COVID-19 vaccine (CHO cells), named NVSI-06-07, as a third dose in participants who have previously received two doses of the inactivated vaccine (BBIBP-CorV) at pre-specified time intervals. Using homologous boost with BBIBP-CorV as control, the safety and immunogenicity of the heterologous boost with NVSI-06-07 against various SARS-CoV-2 strains, including Omicron, were characterized. Methods: This study is a single-center, randomised, double-blinded, controlled phase 2 trial for heterologous boost of NVSI-06-07 in BBIBP-CorV recipients from the United Arab Emirates (UAE). Healthy adults (aged [≥]18 years) were enrolled and grouped by the specified prior vaccination interval of BBIBP-CorV, i.e., 1-3 months, 4-6 months or [≥]6 months, respectively, with 600 individuals per group. For each group, participants were randomly assigned at 1:1 ratio to receive either a heterologous boost of NVSI-06-07 or a homologous booster dose of BBIBP-CorV. The primary outcome was to comparatively assess the immunogenicity between heterologous and homologous boosts at 14 and 28 days post-boosting immunization, by evaluation of the geometric mean titers (GMTs) of IgG and neutralizing antibodies as well as the corresponding seroconversion rate ([≥]4-fold rise in antibody titers). The secondary outcomes were the safety profile of the boosting strategies within 30 days post vaccination. The exploratory outcome was the immune efficacy against Omicron and other variants of concern (VOCs) of SARS-CoV-2. This trial is registered with, NCT05033847. Findings: A total of 1800 individuals who have received two doses of BBIBP-CorV were enrolled, of which 899 participants received a heterologous boost of NVSI-06-07 and 901 received a homologous boost for comparison. No vaccine-related serious adverse event (SAE) and no adverse events of special interest (AESI) were reported. 184 (20.47%) participants in the heterologous boost groups and 177 (19.64%) in the homologous boost groups reported at least one adverse reaction within 30 days. Most of the local and systemic adverse reactions reported were grades 1 (mild) or 2 (moderate), and there was no significant difference in the overall safety between heterologous and homologous boosts. Immunogenicity assays showed that the seroconversion rates in neutralizing antibodies against prototype SARS-CoV-2 elicited by heterologous boost were 89.96% - 97.52% on day 28 post-boosting vaccination, which was much higher than what was induced by homologous boost (36.80% - 81.75%). Similarly, in heterologous NVSI-06-07 booster groups, the neutralizing geometric mean titers (GMTs) against the prototype strain increased by 21.01 - 63.85 folds from baseline to 28 days post-boosting vaccination, whereas only 4.20 - 16.78 folds of increases were observed in homologous BBIBP-CorV booster group. For Omicron variant, the neutralizing antibody GMT elicited by the homologous boost of BBIBP-CorV was 37.91 (95%CI, 30.35-47.35), however, a significantly higher level of neutralizing antibodies with GMT 292.53 (95%CI, 222.81-384.07) was induced by the heterologous boost of NVSI-06-07, suggesting that it may serve as an effective boosting strategy combating the pandemic of Omicron. The similar results were obtained for other VOCs, including Alpha, Beta and Delta, in which the neutralizing response elicited by the heterologous boost was also significantly greater than that of the homologous boost. In the participants primed with BBIBP-CorV over 6 months, the largest increase in the neutralizing GMTs was obtained both in the heterologous and homologous boost groups, and thus the booster vaccination with over 6 months intervals was optimal. Interpretation: Our findings indicated that the heterologous boost with NVSI-06-07 was safe, well-tolerated and immunogenic in adults primed with a full regimen of BBIBP-CorV. Compared to homologous boost with a third dose of BBIBP-CorV, incremental increases in immune responses were achieved by the heterologous boost with NVSI-06-07 against SARS-CoV-2 prototype strain, Omicron variant, and other VOCs. The heterologous BBIBP-CorV/NVSI-06-07 prime-boosting vaccination may be valuable in preventing the pandemic of Omicron. The optimal booster strategy was the heterologous boost with NVSI-06-07 over 6 months after a priming with two doses of BBIBP-CorV.

COVID-19 , Drug-Related Side Effects and Adverse Reactions
researchsquare; 2021.


The SARS-CoV-2 variant VUI/202012/01 has been reported to spread unexpectedly fast in the United Kingdom. It is estimated that its transmissibility may increase by 70%. In this study, the top five variants circulating in the UK including D614G+L18F+A222V, D614G+A222V, D614G+S477N, VUI/202012/01 and D614G+69-70del+439K were analyzed for their infective and neutralizing characteristics. The pseudotyped viruses were constructed for the five variants and 12 single mutants composed those variants. We found that the VUI/202012/01 variant does enhance its infectivity due to the cumulative effect of multiple mutations including 69-70del and 144/145del mutations in NTD, A570D in RBD, and S982A in S2. Meanwhile, mutations N501Y, N439K and S477N in RBD can cause a significant decrease in the neutralization activity for some mAbs. Although VUI/202012/01 did not affect the neutralization effect of convalescent sera, it affected the neutralization activity of animal immunized sera by RBD protein or recombinant spike DNA to some extent.