Nature medicine
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Recombinant vesicular stomatitis virus-Zaire Ebola virus (rVSV-ZEBOV) is the most advanced Ebola virus vaccine candidate and is currently being used to combat the outbreak of Ebola virus disease (EVD) in the Democratic Republic of the Congo (DRC). Here we examine the humoral immune response in a subset of human volunteers enrolled in a phase 1 rVSV-ZEBOV vaccination trial by performing comprehensive single B cell and electron microscopy structure analyses. Four studied vaccinees show polyclonal, yet reproducible and convergent B cell responses with shared sequence characteristics. ⋯ Moreover, in all vaccinees, we detected highly potent EBOV-neutralizing antibodies with activities comparable or superior to the monoclonal antibodies currently used in clinical trials. These include antibodies combining the IGHV3-15/IGLV1-40 immunoglobulin gene segments that were identified in all investigated individuals. Our findings will help to evaluate and direct current and future vaccination strategies and offer opportunities for novel EVD therapies.
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Randomized Controlled Trial
Gut microbiome alteration in MORDOR I: a community-randomized trial of mass azithromycin distribution.
The MORDOR I trial1, conducted in Niger, Malawi and Tanzania, demonstrated that mass azithromycin distribution to preschool children reduced childhood mortality1. However, the large but simple trial design precluded determination of the mechanisms involved. Here we examined the gut microbiome of preschool children from 30 Nigerien communities randomized to either biannual azithromycin or placebo. ⋯ Metagenomic analysis revealed functional differences in gut bacteria between treatment groups. Resistome analysis showed an increase in macrolide resistance gene expression in gut microbiota in communities treated with azithromycin (P = 0.004). These results suggest that prolonged mass azithromycin distribution to reduce childhood mortality reduces certain gut bacteria, including known pathogens, while selecting for antibiotic resistance.
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Randomized Controlled Trial Multicenter Study
Dabrafenib, trametinib and pembrolizumab or placebo in BRAF-mutant melanoma.
Blocking programmed death 1 (PD-1) may enhance the durability of anti-tumor responses that are induced by the combined inhibition of BRAF and MEK1. Here we performed a randomized phase 2 trial ( NCT02130466 ), in which patients with treatment-naive BRAFV600E/K-mutant, advanced melanoma received the BRAF inhibitor dabrafenib and the MEK inhibitor trametinib together with the PD-1-blocking antibody pembrolizumab (triplet; n = 60) or placebo (doublet; n = 60). The primary end point of progression-free survival was numerically improved in the triplet group-16.0 months-compared with 10.3 months in the doublet group (hazard ratio, 0.66; P = 0.043); however, the trial did not reach the planned benefit for a statistically significant improvement. ⋯ Grade 3-5 treatment-related adverse events occurred in 58.3 and 26.7% of patients treated with triplet and doublet therapies, respectively, which were most commonly fever, increased transaminase levels and rash. One patient who received triplet therapy died of pneumonitis. In summary, triplet therapy with dabrafenib, trametinib and pembrolizumab conferred numerically longer progression-free survival and duration of response with a higher rate of grade 3/4 adverse events compared with the doublet therapy of dabrafenib, trametinib and placebo.