Meningococcal Group A, C Bivalent Polysaccharide Conjugate Vaccine(Walvax Biotechnology Co., Ltd.)

Objective: The aim of this study was to evaluate the safety and immunogenicity of the first domestic ACYW135 meningococcal conjugate vaccine and a control vaccine named AC group meningococcal conjugate vaccine for 3 months (90-119 days) infants. Methods: From February 2017 to June 2018, a randomized, blinded, and similar vaccine-controlled clinical trial design was adopted at the Henan Vaccine Clinical Research Base. The subjects were 3 months old healthy infants, a total of 720, based on a 1∶1 ratio. The random allocation table for entry was randomly assigned to the experimental group and the control group. According to the 3, 4, and 5 month-old vaccination procedures, the subjects were vaccinated with test vaccine (ACYW135 group meningococcal conjugate vaccine) and control vaccine (group A group C meningococcal polysaccharide conjugate vaccine), of which 720 were given the first dose, 696 were given the second dose (test group: 346; control group: 350), and 692 were given the third dose (test group: 344; Control group: 348). Results: The overall adverse reaction rate of the test vaccine was 21.90% (230 cases), which was lower than the 32.04% (339 cases) of the control vaccine (P<0.001). The incidence of systemic adverse reactions was 19.52% (205 cases), which was lower than that of the control vaccine (27.69%) (293 cases) (P<0.001). The local adverse reaction rate was 3.04% (32 cases), which was lower than the control group (7.84%) (83 cases) (P<0.001). The graded adverse reaction test vaccine was 0.57% (6 cases), which was lower than the control group of 2.36% (25 cases) (P<0.001). The positive conversion rate of anti-bacterial serum antibodies showed that there was no significant difference between the test vaccine group A (91.42%), C (88.76%) and the control vaccine (92.92%) (87.02%) (P>0.05). Group Y and W135 was 88.17% (298 cases), 99.41% (336 cases), respectively. The GMT results showed that the test vaccine group A was 56.24, the control vaccine was 57.43 (P>0.05); the group C test vaccine (43.53) was higher than the control group (27.28) (P<0.001). The group Y and W135 are 89.22 and 140.66, respectively. Among them, the proportion of the group C GMT antibody ≥ 1∶128 for test vaccine (31.07%, 105 cases) was higher than the control vaccine (16.22%, 55 cases) (P<0.001). Conclusion: ACYW135 group meningococcal conjugate vaccine has more safety and immunogenicity after application to 3 month old infants.

Fever is a systemic inflammatory response of the body to pyrogens. Nuclear factor κB (NF-κB) is a central signaling molecule that causes the excessive secretion of various pyrogen-induced pro-inflammatory factors. This study explored the feasibility of a novel reporter gene assay (RGA) for pyrogen detection using RAW264.7 cells stably transfected with the NF-κB reporter gene as a pyrogenic marker. The RGA could detect different types of pyrogens, including the lipopolysaccharide of gram-negative bacteria, the lipoteichoic acid of gram-positive bacteria, and the zymosan of fungi, and a good dose-effect relationship was observed in terms of NF-κB activity. The limits of detection of the RGA to those pyrogens were 0.03 EU/ml, 0.001 μg/ml, and 1 μg/ml, respectively. The method had good precision and accuracy and could be applied to many molecules (e.g., nivolumab, rituximab, bevacizumab, etanercept, basiliximab, Haemophilus influenzae type b conjugate vaccine, 23-valent pneumococcal polysaccharide vaccine, group A and group C meningococcal conjugate vaccine, diphtheria, tetanus, pertussis [acellular, component], poliomyelitis [inactivated] vaccine, and imject alum adjuvant). The results of this study suggest that the novel RGA has a wide pyrogen detection spectrum and is sufficiently sensitive, stable, and accurate for various applications.