Safety and immunogenicity of a SARS-CoV-2 recombinant protein nanoparticle vaccine (GBP510) adjuvanted with AS03: a phase 1/2, randomized, placebo-controlled, observer-blinded trial

BackgroundVaccination has helped to mitigate the COVID-19 pandemic. Ten traditional and novel vaccines have been listed by the World Health Organization for emergency use. Additional alternative approaches may better address ongoing vaccination globally, where there remains an inequity in vaccine distribution. GBP510 is a recombinant protein vaccine, which consists of self-assembling, two-component nanoparticles displaying the receptor-binding domain (RBD) in a highly immunogenic array. MethodsWe conducted a randomized, placebo-controlled, observer-blinded, phase 1/2 trial to evaluate the safety and immunogenicity of GBP510 (2-doses at a 28-day interval) adjuvanted with or without AS03 in adults aged 19-85 years. The main outcomes included solicited and unsolicited adverse events; anti-SARS-CoV-2 RBD IgG antibody and neutralizing antibody responses; T-cell immune responses. FindingsOf 328 participants who underwent randomization, 327 participants received at least 1 dose of vaccine. Each received either 10 g GBP510 adjuvanted with AS03 (n = 101), 10 g unadjuvanted GBP510 (n = 10), 25 g GBP510 adjuvanted with AS03 (n = 104), 25 g unadjuvanted GBP510 (n = 51), or placebo (n = 61). Most solicited adverse events were mild-to-moderate in severity and transient. Higher reactogenicity was observed in the GBP510 adjuvanted with AS03 groups compared to the non-adjuvanted and placebo groups. Reactogenicity was higher post-dose 2 compared to post-dose 1, particularly for systemic adverse events. The geometric mean concentrations of anti-SARS-CoV-2-RBD IgG antibody reached 2163.6/2599.2 BAU/mL in GBP510 adjuvanted with AS03 recipients (10 g/25 g) by 14 days after the second dose. Two-dose vaccination with 10 g or 25 g GBP510 adjuvanted with AS03 induced high titers of neutralizing antibody via pseudovirus (1369.0/1431.5 IU/mL) and wild-type virus (949.8/861.0 IU/mL) assays. InterpretationGBP510 adjuvanted with AS03 was well tolerated and highly immunogenic. These results support further development of the vaccine candidate, which is currently being evaluated in Phase 3. FundingCoalition for Epidemic Preparedness Innovations RESEARCH IN CONTEXTO_ST_ABSEvidence before this studyC_ST_ABSWe searched PubMed for research articles published by December 31, 2021, using the terms "COVID-19" or "SARS-CoV-2," "vaccine," and "clinical trial." In previously reported randomized clinical trials, we found that mRNA vaccines were more immunogenic than adenovirus-vectored vaccines. Solicited adverse events were more frequent and more severe in intensity after the first dose compared to the second dose for adenovirus-vectored vaccines, whereas they increased after the second dose of mRNA or recombinant spike-protein nanoparticle vaccines. Added value of this studyThis is the first human study evaluating the immunogenicity and safety of recombinant SARS-CoV-2 protein nanoparticle with and without adjuvant AS03, designed to elicit functional cross-protective responses via receptor-binding domain (RBD). Both 10 and 25 g of GBP510 with AS03 formulations were well tolerated with an acceptable safety profile. Potent humoral immune responses against the SARS-CoV-2 RBD were induced and peaked by day 42 (14 days after the second dose). In addition, GBP510 adjuvanted with AS03 elicited a noticeable Th1 response, with production of IFN-{gamma}, TNF-, and IL-2. IL-4 was inconsistent and IL-5 nearly inexistent response across all groups. Implications of the available evidenceThe results from this phase 1/2 trial indicate that GBP510 adjuvanted with AS03 has an acceptable safety profile with no vaccine-related serious adverse events. Two-dose immunization with GBP510 adjuvanted with AS03 induced potent humoral and cellular immune responses against SARS-CoV-2.

The Differences Between Cyclosporine and Tacrolimus in the Generation of ROS and Extracellular Matrix Accumulation in Primary Cultured Human Mesangial Cells / 대한신장학회잡지

OBJECTIVE: Cyclosporine(CsA) and tacrolimus, albeit different in structure, exert immunosuppressive effect by similar mechanism. Although most of clinical manifestations, including nephrotoxicity, are similar in the patients using these drugs, there are some differences including gum hyperplasia, neurotoxicity, and hepatic fibrosis between two drugs. There are several reports about association between reactive oxygen species(ROS) and CsA. In contrast, tacrolimus is known to decrease ROS in central nervous system. Thus, we investigated the possibility of different effects of tacrolimus and CsA on the generation of ROS, on the synthesis and degradation of collagen. METHODS: Experiments were done in primary cultured mesangial cells between 4th and 8th passages. CsA was added to the culture dishes in different concentration(making final CsA concentration of 0, 2, 4, 8 microgram/milliliter) and N-acetylcysteine(NAC) was also added in another mesangial cell culture at 4 microgram/milliliter of CsA concentration; tacrolimus was added in similar pattern(making final tacrolimus concentration of 0, 0.1, 0.2, 0.4 microgram/milliliter, NAC in 0.2 microgram/milliliter of tacrolimus concentration). RESULTS: No significant decrease in viability was noted in both cell groups, but growth retardation was weak in tacrolimus treated cells comparing with CsA treated cells. By flow cytometry, we could find the generation of ROS in CsA treated cells, but not in tacrolimus treated cells. In RT-PCR, there is no significant difference in m-RNA expression for a number of molecules including collagen III, MMP-2, TIMP-2, MT1-MMP in either CsA treated cells or tacrolimus cells. But in zymogram, MMP-2 activities were decreased at higher CsA concentration, then increased with addition of NAC. In tacrolimus cells, MMP2 activity was not changed at 0.1 and 0.2 microgram/milliliter; but, at the concentration of 0.4 microgram/milliliter, changed and not reversed by NAC. MMP-9 activity was similar in both cells. CONCLUSION: We could find ROS generation in CsA treated human mesangial cells, but not in tacrolimus treated cells. We think this difference resulted in the decrease of post-transcriptional MMP-2 activity in CsA treated cells and we also think tacrolimus cells in our experiments were not influenced by ROS. From these results, tacrolimus and CsA are different in the generation of ROS that have some effects in the matrix accumulation in mesangial cells. These result does not mean that tacrolimus is superior to CsA in nephrotoxicity, because nephrotoxicity is similar between two drugs. In conclusion, the mechanisms of nephrotoxicity are different between CsA and tacrolimus.

The Effects of Cyclosporine on the Generation of ROS and Extracellular Matrix Accumulation in Cultured Human Mesangial Cells / 대한신장학회잡지

OBJECTIVE: Treatment with cyclosporine(CsA) for a long-term period may induce renal glomerulosclersosis and interstitial fibrosis. Reactive oxygen species(ROS) seems to be involved in the process of glomerulosclersosis and interstitial fibrosis. We investigated the effect of CsA on the generation of ROS and extracellular matrix accumulation in cultured human mesangial cells. We also studied the relationship between ROS formation and extracellular matrix and the effect of antioxidant on ROS formation and/or extracellular matrix degradation. METHODS: Mesangial cells were treated with varying dose of Cyclosporine(0, 2.5, 5, 7.5 and 10microgram/ mL) and also with cyclosporine(5microgram/mL) plus N- acetylcysteine(1mM). ROS was measured by flow cytometric analysis. mRNA expression of MMP-2, TIMP-2, MT1-MMP and collagen III was assessed by RT-PCR method. MMP-2 activity was measured by gelatin zymography. RESULTS: No significant difference was noted in cell viability with each CsA concentration. CsA inhibited the cell proliferation in a dose dependent manner and induced the expression of ROS. Antioxidant NAC reversed the effect of cyclosporine. CsA had no effect on the mRNA expression of collagen III, MMP-2, TIMP-2, MT1-MMP. However CsA decreased the MMP-2 activity in a dose dependent manner, which was also reversed by NAC. CONCLUSION: Cyclosporine-induced ROS may be associated with the extracellular matrix accumulation, that is glomerulosclersosis and interstitial fibrosis by inhibiting the cell proliferation and by decreasing the degradation of extracellular matrix. Antioxidant, at least in vitro, may prevent some of the adverse effects of CsA on renal function.