The efficacy, safety and immunogenicity Nanocovax: results of a randomized, double-blind, placebo-controlled Phase 3 trial.

BackgroundNanocovax is a recombinant severe acute respiratory syndrome coronavirus 2 subunit vaccine composed of full-length prefusion stabilized recombinant SARS-CoV-2 spike glycoproteins (S-2P) and aluminum hydroxide adjuvant. In a Phase 1 and 2 studies, (NCT04683484) the vaccine was found to be safe and induce a robust immune response in healthy adult participants. MethodsWe conducted a multicenter, randomized, double-blind, placebo-controlled study to evaluate the safety, immunogenicity, and protective efficacy of the Nanocovax vaccine against Covid-19 in approximately 13,007 volunteers aged 18 years and over. The immunogenicity was assessed based on Anti-S IgG antibody response, surrogate virus neutralization, wild-type SARS-CoV-2 neutralization and the types of helper T-cell response by intracellular staining (ICS) for interferon gamma (IFNg) and interleukin-4 (IL-4). The vaccine efficacy (VE) was calculated basing on serologically confirmed cases of Covid-19. FindingsUp to day 180, incidences of solicited and unsolicited adverse events (AE) were similar between vaccine and placebo groups. 100 serious adverse events (SAE) were observed in both vaccine and placebo groups (out of total 13007 participants). 96 out of these 100 SAEs were determined to be unrelated to the investigational products. 4 SAEs were possibly related, as determined by the Data and Safety Monitoring Board (DSMB) and investigators. Reactogenicity was absent or mild in the majority of participants and of short duration. These findings highlight the excellent safety profile of Nanocovax. Regarding immunogenicity, Nanocovax induced robust IgG and neutralizing antibody responses. Importantly, Anti S-IgG levels and neutralizing antibody titers on day 42 were higher than those of natural infected cases. Nanocovax was found to induce Th2 polarization rather than Th1. Post-hoc analysis showed that the VE against symptomatic disease was 51.5% (95% confidence interval [CI] was [34.4%-64.1%]. VE against severe illness and death were 93.3% [62.2-98.1]. Notably, the dominant strain during the period of this study was Delta variant. InterpretationNanocovax 25 microgram (mcg) was found to be safe with the efficacy against symptomatic infection of Delta variant of 51.5%. FundingResearch was funded by Nanogen Pharmaceutical Biotechnology JSC., and the Ministry of Science and Technology of Vietnam; ClinicalTrials.gov number, NCT04922788.

Use skin allograft collected from parent combined with autograft for deep and large burns in children

Study on 17 pediatric patients aged from 1 to 12 years of old, 14 boys and 3 girls. Burn-caused agents were dry heat, wet-heat and chemicals. Patients were divided randomly into 2 groups: Group A (Study group) involved 10 patients with mean age of 5 years, average common burn area was 41% of body area and deep burn area was 35% of body area. Group B (control group) included 7 patients with mean age of 6 years. The average common burn area of these patients was 48% of body area and the deep burn area was 34%. In group A, the bacterial infection incidence was lower markedly than group B (p<0.05). P. aeruginosa caused sepsis had highest incidence (66.6%) in patients with positive culture. Skin implantation produced good and moderate results in group A. 10 patients received skin allograft in 16 operations. Mean time survival of skin grafts is 14.92 days.

The microbial change in the deep burn in children before and after operation for the necrosis removal

61 children with the deep burn (male: 40; female: 21), avarage ages of 6.3 the avarage burn area: 33%; the avarage deep burn area: 21% were admitted after 10 days of burn participated to a study. The results have shown that the highest rate of pseudomonas aeruginosa reported, there were no change of microorganism in the burn area before and after the necrosis removal. The density of microbial per one gram of the necrosis tissues after the necrosis removal reduced in significantly. There was a linear relation between the density of microbial in the burn tissues, the clinical infective symptoms and the rate of the septicemia in the deep burn. The technique of the method of the quantitative analysis of microbials/one gram tissue had a high confidence.

Primarily opinions of complete and early necrotic removal and one-stage thin cutaneous transplantation in the treatment of deep burn in children

22 pediatric patients with the deep burn at grade VII (male: 15) received complete and early necrotic removal and one-stage thin cutaneous transplantation have shown that the technique reduced the edema, fluid excretion and local pus and shortened the duration for burn healing comparing with the necrotic removal and waiting for the generation of granular tissue to transplant. The study concluded that it should remove radically the necrosis, prevent from blood clotting in the transplant and operate within the first 7 days of burn.