XANTUS-EL: A real-world, prospective, observational study of patients treated with rivaroxaban for stroke prevention in atrial fibrillation in Eastern Europe, Middle East, Africa and Latin America.

BACKGROUND: The prospective, observational XANTUS study demonstrated low rates of stroke and major bleeding in real-world rivaroxaban-treated patients with non-valvular atrial fibrillation (NVAF) from Western Europe, Canada and Israel. XANTUS-EL is a component of the overall XANTUS programme and enrolled patients with NVAF treated with rivaroxaban from Eastern Europe, the Middle East and Africa (EEMEA) and Latin America. METHODS: Patients with NVAF starting rivaroxaban for stroke prevention were consecutively recruited and followed for 1 year, at approximately 3-month intervals, or for ≥30 days after permanent rivaroxaban discontinuation. Primary outcomes were major bleeding, adverse events (AEs), serious AEs and all-cause mortality. Secondary outcomes included stroke, non-central nervous system systemic embolism (non-CNS SE), transient ischaemic attack (TIA), myocardial infarction (MI) and non-major bleeding. All major outcomes were centrally adjudicated. RESULTS: Overall, 2064 patients were enrolled; mean age ±â€¯standard deviation was 67.1 ±â€¯11.32 years; 49.3% were male. Co-morbidities included heart failure (30.9%), hypertension (84.2%), diabetes mellitus (26.5%), prior stroke/non-CNS SE/TIA (16.2%) and prior MI (10.7%). Mean CHADS2, CHA2DS2-VASc and HAS-BLED scores were 2.0, 3.6 and 1.6, respectively. Treatment-emergent event rates were (events/100 patient-years, [95% confidence interval]): major bleeding 0.9 (0.5-1.4); all-cause mortality 1.7 (1.2-2.4); stroke/non-CNS SE 0.7 (0.4-1.2); any AE 18.1 (16.2-20.1) and any serious AE 8.3 (7.0-9.7). One-year treatment persistence was 81.9%. CONCLUSIONS: XANTUS-EL confirmed low stroke and major bleeding rates in patients with NVAF from EEMEA and Latin America. The population was younger but with more heart failure and hypertension than XANTUS; stroke/SE rate was similar but major bleeding lower.

Immunogenicity and safety of investigational vaccine formulations against meningococcal serogroups A, B, C, W, and Y in healthy adolescents.

This phase 2 study assessed the immunogenicity, safety, and reactogenicity of investigational formulations of meningococcal ABCWY vaccines, consisting of recombinant proteins (rMenB) and outer membrane vesicle (OMV) components of a licensed serogroup B vaccine, combined with components of a licensed quadrivalent meningococcal glycoconjugate vaccine (MenACWY-CRM). A total of 495 healthy adolescents were randomized to 6 groups to receive 2 doses (Months 0, 2) of one of 4 formulations of rMenB antigens, with or without OMV, combined with MenACWY-CRM, or 2 doses of rMenB alone or one dose of MenACWY-CRM then a placebo. Immunogenicity was assessed by serum bactericidal assay with human complement (hSBA) against serogroups ACWY and serogroup B test strains; solicited reactions and any adverse events (AEs) were assessed. Two MenABCWY vaccinations elicited robust ACWY immune responses, with higher seroresponse rates than one dose of MenACWY-CRM. Bactericidal antibody responses against the rMenB antigens and OMV components were highest in subjects who received 2 doses of OMV-containing MenABCWY formulations, with ≥68% of subjects achieving hSBA titers ≥5 against each of the serogroup B test strains. After the first dose, solicited local reaction rates were higher in the MenABCWY or rMenB groups than the MenACWY-CRM group, but similar across groups after the second dose, consisting mainly of transient injection site pain. Fever (≥38.0°C) was rare and there were no vaccine-related serious AEs. In conclusion, investigational MenABCWY formulations containing OMV components elicited highly immunogenic responses against meningococcal serogroups ACWY, as well as serogroup B test strains, with an acceptable safety profile. [NCT01210885].

Assessment of bivalent and tetravalent dengue vaccine formulations in flavivirus-naïve adults in Mexico.

UNLABELLED: Several ChimeriVax-Dengue (CYD)-based vaccination strategies were investigated as potential alternatives to vaccination with tetravalent CYD vaccine (CYD-TDV) in this phase IIa trial conducted in 2008-9 in 150 healthy adults. Participants were randomized and vaccinated on D0 and D105 (± 15 days). One group received bivalent CYD vaccine against serotypes 1 and 3 (CYD-1;3) on day 0 and CYD-2;4 on day 105 (± 15 days). Two groups received an injection at each timepoint of a tetravalent blend of CYD-1;3;4 and a VERO cell derived, live attenuated vaccine against serotype 2 (VDV-2), or the reference CYD-TDV. A fourth group received Japanese encephalitis (JE) vaccine on days -14, -7 and 0, followed by CYD-TDV on day 105. Viraemia was infrequent in all groups. CYD-4 viraemia was most frequent after tetravalent vaccination, while CYD-3 viraemia was most frequent after the first bivalent vaccination. Immunogenicity as assessed by 50% plaque reduction neutralisation test on D28 was comparable after the first injection of either tetravalent vaccine, and increased after the second injection, particularly with the blended CYD-1;3;4/ VDV-2 vaccine. In the bivalent vaccine group, immune response against serotype 3 was highest and the second injection elicited a low immune response against CYD 2 and 4. Immune responses after the first injection of CYD-TDV in the JE-primed group were in general higher than after the first injection in the other groups. All tested regimens were well tolerated without marked differences between groups. Bivalent vaccination showed no advantage in terms of immunogenicity. CLINICAL TRIAL REGISTRATION NUMBER: NCT00740155.