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1.
PLoS Negl Trop Dis ; 17(3): e0011236, 2023 03.
Article in English | MEDLINE | ID: covidwho-2293922

ABSTRACT

BACKGROUND: Recombinant Schistosoma mansoni Tetraspanin-2 formulated on Alhydrogel (Sm-TSP-2/Alhydrogel) is being developed to prevent intestinal and hepatic disease caused by S. mansoni. The tegumentary Sm-TSP-2 antigen was selected based on its unique recognition by cytophilic antibodies in putatively immune individuals living in areas of ongoing S. mansoni transmission in Brazil, and preclinical studies in which vaccination with Sm-TSP-2 protected mice following infection challenge. METHODS: A randomized, observer-blind, controlled, Phase 1b clinical trial was conducted in 60 healthy adults living in a region of Brazil with ongoing S. mansoni transmission. In each cohort of 20 participants, 16 were randomized to receive one of two formulations of Sm-TSP-2 vaccine (adjuvanted with Alhydrogel only, or with Alhydrogel plus the Toll-like receptor-4 agonist, AP 10-701), and 4 to receive Euvax B hepatitis B vaccine. Successively higher doses of antigen (10 µg, 30 µg, and 100 µg) were administered in a dose-escalation fashion, with progression to the next dose cohort being dependent upon evaluation of 7-day safety data after all participants in the preceding cohort had received their first dose of vaccine. Each participant received 3 intramuscular injections of study product at intervals of 2 months and was followed for 12 months after the third vaccination. IgG and IgG subclass antibody responses to Sm-TSP-2 were measured by qualified indirect ELISAs at pre- and post-vaccination time points through the final study visit. RESULTS: Sm-TSP-2/Alhydrogel administered with or without AP 10-701 was well-tolerated in this population. The most common solicited adverse events were mild injection site tenderness and pain, and mild headache. No vaccine-related serious adverse events or adverse events of special interest were observed. Groups administered Sm-TSP-2/Alhydrogel with AP 10-701 had higher post-vaccination levels of antigen-specific IgG antibody. A significant dose-response relationship was seen in those administered Sm-TSP-2/Alhydrogel with AP 10-701. Peak anti-Sm-TSP-2 IgG levels were observed approximately 2 weeks following the third dose, regardless of Sm-TSP-2 formulation. IgG levels fell to low levels by Day 478 in all groups except the 100 µg with AP 10-701 group, in which 57% of subjects (4 of 7) still had IgG levels that were ≥4-fold higher than baseline. IgG subclass levels mirrored those of total IgG, with IgG1 being the predominant subclass response. CONCLUSIONS: Vaccination of adults with Sm-TSP-2/Alhydrogel in an area of ongoing S. mansoni transmission was safe, minimally reactogenic, and elicited significant IgG and IgG subclass responses against the vaccine antigen. These promising results have led to initiation of a Phase 2 clinical trial of this vaccine in an endemic region of Uganda. TRIAL REGISTRATION: NCT03110757.


Subject(s)
Schistosomiasis mansoni , Animals , Humans , Mice , Adjuvants, Immunologic , Aluminum Hydroxide , Brazil , Immunoglobulin G , Schistosoma mansoni , Protozoan Vaccines
2.
Clin Infect Dis ; 2023 Apr 10.
Article in English | MEDLINE | ID: covidwho-2292557

ABSTRACT

In a randomized clinical trial, we compare early neutralizing antibody responses after boosting with bivalent SARS-CoV-2 mRNA vaccines based on either BA.1 or BA.4/BA.5 Omicron spike protein combined with wildtype spike. Responses against SARS-CoV-2 variants exhibited the greatest reduction in titers against currently circulating Omicron subvariants for both bivalent vaccines.

4.
J Med Internet Res ; 23(1): e21408, 2021 01 14.
Article in English | MEDLINE | ID: covidwho-1030259

ABSTRACT

BACKGROUND: The use of social media assists in the distribution of COVID-19 information to the general public and health professionals. Alternative-level metrics (ie, altmetrics) and PlumX metrics are new bibliometrics that can assess how many times a scientific article has been shared and how much a scientific article has spread within social media platforms. OBJECTIVE: Our objective was to characterize and compare the traditional bibliometrics (ie, citation count and impact factors) and new bibliometrics (ie, Altmetric Attention Score [AAS] and PlumX score) of the top 100 COVID-19 articles with the highest AASs. METHODS: The top 100 articles with highest AASs were identified with Altmetric Explorer in May 2020. The AASs, journal names, and the number of mentions in various social media databases of each article were collected. Citation counts and PlumX Field-Weighted Citation Impact scores were collected from the Scopus database. Additionally, AASs, PlumX scores, and citation counts were log-transformed and adjusted by +1 for linear regression, and Spearman correlation coefficients were used to determine correlations. RESULTS: The median AAS, PlumX score, and citation count were 4922.50, 37.92, and 24.00, respectively. The New England Journal of Medicine published the most articles (18/100, 18%). The highest number of mentions (985,429/1,022,975, 96.3%) were found on Twitter, making it the most frequently used social media platform. A positive correlation was observed between AAS and citation count (r2=0.0973; P=.002), and between PlumX score and citation count (r2=0.8911; P<.001). CONCLUSIONS: Our study demonstrated that citation count weakly correlated with AASs and strongly correlated with PlumX scores, with regard to COVID-19 articles at this point in time. Altmetric and PlumX metrics should be used to complement traditional citation counts when assessing the dissemination and impact of a COVID-19 article.


Subject(s)
Bibliometrics , COVID-19 , Information Dissemination , SARS-CoV-2 , Social Media , Correlation of Data , Humans
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