Safety, tolerability, pharmacokinetic, pharmacodynamic and immunogenicity profiles of Exendin-4-IgG4-Fc in healthy subjects: A phase 1, single-centre, randomized, double-blind, dose escalation study

AIM

Novel long-acting drugs for type 2 diabetes mellitus may optimize patient compliance and glycaemic control. Exendin-4-IgG4-Fc (E4F4) is a long-acting glucagon-like peptide-1 receptor agonist. This first-in-human study investigated the safety, tolerability, pharmacokinetic, pharmacodynamic and immunogenicity profiles of a single subcutaneous injection of E4F4 in healthy subjects.

METHODS

This single-centre, randomized, double-blind, placebo-controlled phase 1 clinical trial included 96 subjects in 10 sequential cohorts that were provided successively higher doses of E4F4 (0.45, 0.9, 1.8, 3.15, 4.5, 6.3, 8.1, 10.35, 12.6 and 14.85 mg) or placebo (ChinaDrugTrials.org.cn: ChiCTR2100049732). The primary endpoint was safety and tolerability of E4F4. Secondary endpoints were pharmacokinetic, pharmacodynamic and immunogenicity profiles of E4F4. Safety data to day 15 after the final subject in a cohort had been dosed were reviewed before commencing the next dose level.

RESULTS

E4F4 was safe and well tolerated among healthy Chinese participants in this study. There was no obvious dose-dependent relationship between frequency, severity or causality of treatment-emergent adverse events. Cmax and area under the curve of E4F4 were dose proportional over the 0.45-14.85 mg dose range. Median Tmax and t1/2 ranged from 146 to 210 h and 199 to 252 h, respectively, across E4F4 doses, with no dose-dependent trends. For the intravenous glucose tolerance test, area under the curve of glucose in plasma from time 0 to 180 min showed a dose-response relationship in the 1.8-10.35 mg dose range, with an increased response at the higher doses.

CONCLUSION

E4F4 exhibited an acceptable safety profile and linear pharmacokinetics in healthy subjects. The recommended phase 2 dose is 4.5-10.35 mg once every 2 weeks.

Immunogenicity and safety of NVSI-06-07 as a heterologous booster after priming with BBIBP-CorV: a phase 2 trial

The increased coronavirus disease 2019 (COVID-19) breakthrough cases pose the need of booster vaccination. We conducted a randomised, double-blinded, controlled, phase 2 trial to assess the immunogenicity and safety of the heterologous prime-boost vaccination with an inactivated COVID-19 vaccine (BBIBP-CorV) followed by a recombinant protein-based vaccine (NVSI-06-07), using homologous boost with BBIBP-CorV as control. Three groups of healthy adults (600 individuals per group) who had completed two-dose BBIBP-CorV vaccinations 1-3 months, 4-6 months and ≥6 months earlier, respectively, were randomly assigned in a 1:1 ratio to receive either NVSI-06-07 or BBIBP-CorV boost. Immunogenicity assays showed that in NVSI-06-07 groups, neutralizing antibody geometric mean titers (GMTs) against the prototype SARS-CoV-2 increased by 21.01-63.85 folds on day 28 after vaccination, whereas only 4.20-16.78 folds of increases were observed in control groups. For Omicron variant, the neutralizing antibody GMT elicited by homologous boost was 37.91 on day 14, however, a significantly higher neutralizing GMT of 292.53 was induced by heterologous booster. Similar results were obtained for other SARS-CoV-2 variants of concerns (VOCs), including Alpha, Beta and Delta. Both heterologous and homologous boosters have a good safety profile. Local and systemic adverse reactions were absent, mild or moderate in most participants, and the overall safety was quite similar between two booster schemes. Our findings indicated that NVSI-06-07 is safe and immunogenic as a heterologous booster in BBIBP-CorV recipients and was immunogenically superior to the homologous booster against not only SARS-CoV-2 prototype strain but also VOCs, including Omicron.