Plasmodium falciparum apical membrane antigen 1 (PfAMA1) is a candidate malaria vaccine antigen expressed on merozoites and sporozoites. PfAMA1's polymorphic nature impacts vaccine-induced ...protection. To address polymorphism, three Diversity Covering (DiCo) protein sequences were designed and tested in a staggered phase Ia/b trial. A cohort of malaria-naive adults received PfAMA1-DiCo adjuvanted with Alhydrogel® or GLA-SE and a cohort of malaria-exposed adults received placebo or GLA-SE adjuvanted PfAMA1 DiCo at weeks 0, 4 and 26. IgG and GIA levels measured 4 weeks after the third vaccination are similar in malaria-naive volunteers and placebo-immunised malaria-exposed adults, and have a similar breadth. Vaccination of malaria-exposed adults results in significant antibody level increases to the DiCo variants, but not to naturally occurring PfAMA1 variants. Moreover, GIA levels do not increase following vaccination. Future research will need to focus on stronger adjuvants and/or adapted vaccination regimens, to induce potentially protective responses in the target group of the vaccine.
A candidate AS01-adjuvanted vaccine containing four surface proteins from non-typable Haemophilus influenzae and Moraxella catarrhalis (NTHi-Mcat) has been developed to help prevent exacerbations of ...chronic obstructive pulmonary disease (COPD). Sequential administration of different vaccines containing the same AS01-adjuvant system could lead to immune interference. We compared administration of NTHi-Mcat following AS01-adjuvanted recombinant zoster vaccine (RZV) versus NTHi-Mcat alone. This phase 2a, open-label trial (NCT03894969) randomized healthy current or former smokers (50-80 years) without COPD to administration of NTHi-Mcat at 1, 3 or 6 months after RZV or to NTHi-Mcat alone (2-dose for both vaccines). Primary outcome was non-inferiority of the humoral immune response to NTHi-Mcat administered 1 month after RZV versus NTHi-Mcat alone, evaluated by specific antibody geometric mean concentration (GMC) ratio with 95% confidence intervals (CIs). The per-protocol set included 411 participants. Primary objective was met; lower limit of the 95%CI for the GMC ratio above 0.667 for all four vaccine antigens, 1 month after the second NTHi-Mcat dose. NTHi-Mcat induced similar immune response regardless of whether administered alone or 1, 3 or 6 months following RZV. Safety and reactogenicity profiles were acceptable; adverse event frequency was similar among study groups. Injection site pain was the most common symptom. No new safety concerns were identified. The study demonstrated non-inferiority of the immune response elicited by NTHi-Mcat administered sequentially to RZV versus NTHi-Mcat alone, indicating no immune interference. Starting from 1 month, no specific interval is required between RZV and NTHi-Mcat containing the same AS01-adjuvant system components in different quantities.
In October 2009, the French government organized a national-wide, free of charge vaccination campaign against pandemic H1N1 influenza virus, especially targeting pregnant women, a high risk group for ...severe illness. The study objective was to evaluate pandemic flu vaccine uptake and factors associated with non-vaccination in a population of pregnant women.
In a prospective cohort conducted in 3 maternity hospitals in Paris, 882 pregnant women were randomly included between October 12, 2009 and February 3, 2010, with the aim to study characteristics of pandemic influenza during pregnancy. At inclusion, socio-demographic, medical, obstetrical factors and those associated with a higher risk of flu exposition and disease-spreading were systematically collected. Pandemic flu vaccine uptake was checked until delivery. 555 (62.9%) women did not get vaccinated. Determinants associated with non-vaccination in a multivariate logistic regression were: geographic origin (Sub-Saharan African origin, adjusted Odd Ratio aOR = 5.42.3-12.7, North African origin, aOR = 2.51.3-4.7 and Asian origin, aOR = 2.11.7-2.6 compared to French and European origin) and socio-professional categories (farmers, craftsmen and tradesmen, aOR = 2.32.0-2.6, intermediate professionals, aOR = 1.31.0-1.6, employees and manual workers, aOR = 2.51.4-4.4 compared to managers and intellectual professionals). The probability of not receiving pandemic flu vaccine was lower among women vaccinated against seasonal flu in the previous 5 years (aOR = 0.60.4-0.8) and among those who stopped smoking before or early during pregnancy (aOR = 0.60.4-0.8). Number of children less than 18 years old living at home, work in contact with children or in healthcare area, or professional contact with the public, were not associated with a higher vaccine uptake.
In this cohort of pregnant women, vaccine coverage against pandemic 2009 A/H1N1 flu was low, particularly in immigrant women and those having a low socio-economic status. To improve its effectiveness, future vaccination campaign for pregnant women should be more specifically tailored for these populations.
V591 (TMV-083) is a live recombinant measles vector-based vaccine candidate expressing a pre-fusion stabilized SARS-CoV-2 spike protein.
We performed a randomized, placebo-controlled Phase I trial ...with an unblinded dose escalation and a double-blind treatment phase at 2 sites in France and Belgium to evaluate the safety and immunogenicity of V591. Ninety healthy SARS-CoV-2 sero-negative adults (18-55 years of age) were randomized into 3 cohorts, each comprising 24 vaccinees and 6 placebo recipients. Participants received two intramuscular injections of a low dose vaccine (1 × 105 median Tissue Culture Infectious Dose TCID50), one or two injections of a high dose vaccine (1 × 106 TCID50), or placebo with a 28 day interval. Safety was assessed by solicited and unsolicited adverse events. Immunogenicity was measured by SARS-CoV-2 spike protein-binding antibodies, neutralizing antibodies, spike-specific T cell responses, and anti-measles antibodies. ClinicalTrials.gov, NCT04497298.
Between Aug 10 and Oct 13, 2020, 148 volunteers were screened of whom 90 were randomized. V591 showed a good safety profile at both dose levels. No serious adverse events were reported. At least one treatment-related adverse event was reported by 15 (20.8%) participants receiving V591 vs. 6 (33.3%) of participants receiving placebo. Eighty-one percent of participants receiving two injections of V591 developed spike-binding antibodies after the second injection. However, neutralizing antibodies were detectable on day 56 only in 17% of participants receiving the low dose and 61% receiving the high dose (2 injections). Spike-specific T cell responses were not detected. Pre-existing anti-measles immunity had a statistically significant impact on the immune response to V591, which was in contrast to previous results with the measles vector-based chikungunya vaccine.
While V591 was generally well tolerated, the immunogenicity was not sufficient to support further development.
Themis Bioscience GmbH, a subsidiary of Merck & Co. Inc., Kenilworth, NJ, USA; Coalition for Epidemic Preparedness Innovations (CEPI).
During the Covid-19 pandemic, the urgent need for safe and effective vaccines has led to many vaccine trials, implying fast and extensive recruitment of volunteers. In France, until 2020, vaccine ...clinical research participants were usually recruited locally, through center-based pools of volunteers, and local communication plans. Covireivac is a French public online platform launched on 10/01/2020 that enables national, large-scale recruitment of volunteers for Covid-19 vaccine studies. On the Covireivac website, all adult participants registered online, gave their informed consent, and filled out two online forms with information on their identity, health status (comorbidities, treatments), and known exposure to SARS-CoV-2. Since July 2021, volunteers could mention if their children are interested in participating in a Covid-19 vaccine trial. The objective of this work is to describe Covireivac's volunteer characteristics registered from 10/01/2020 to 11/02/2022. To identify independent volunteer characteristics associated with a period of registration we performed a multivariate logistic regression. Among 54,424 registrations, 52,391 (96%) were analysed; 61% were male (n = 31,893), median age was 50 y; 13% (n = 6586) were healthcare workers. At registration, 15,879 volunteers (33%) reported at least one comorbidity, among whom 16% (n = 7349) were obese and 17% (n = 8346) had hypertension. Most volunteers registered during the first month (n = 35,876, 66%). The Covireivac platform allowed quick and large recruitment of potential volunteers for Covid-19 vaccine trials and could be used on a larger scale for vaccine trials in France. It could facilitate recruitment in vaccine trials and provide sponsors with better visibility of the recruitment capacities of clinical research centers.
Neonates are highly susceptible to infectious diseases and defective antiviral pDC immune responses have been proposed to contribute to this phenomenon. Isolated cord blood pDCs innately responded to ...a variety of TLR7 and TLR9 dependent viruses, including influenza A virus (IAV), human immunodeficiency virus (HIV) or herpes-simplex virus (HSV) by efficiently producing IFN-α, TNF-α as well as chemokines. Interestingly, following activation by CpGA, but not viruses, cord pDCs tend to survive less efficiently. We found that a hallmark of pDCs in neonates is an extended CD2+pDCs compartment compared to adult pDCs without affecting the antiviral IFN-α response. Within CD2+pDCs, we identified a subpopulation expressing CD5 and responsible for IL-12p40 production, however this population is significantly decreased in cord blood compared to adult blood. Therefore, neonatal pDCs clearly display variation in phenotype and subset composition, but without major consequences for their antiviral responses.
Human immunodeficiency virus type 1 (HIV-1) resistance to protease inhibitors (PI) results from mutations in the viral protease (PR) that reduce PI binding but also decrease viral replicative ...capacity (RC). Additional mutations compensating for the RC loss subsequently accumulate within PR and in Gag substrate cleavage sites. We examined the respective contribution of mutations in PR and Gag to PI resistance and RC and their interdependence using a panel of HIV-1 molecular clones carrying different sequences from six patients who had failed multiple lines of treatment. Mutations in Gag strongly and directly contributed to PI resistance besides compensating for fitness loss. This effect was essentially carried by the C-terminal region of Gag (containing NC-SP2-p6) with little or no contribution from MA, CA, and SP1. The effect of Gag on resistance depended on the presence of cleavage site mutations A431V or I437V in NC-SP2-p6 and correlated with processing of the NC/SP2 cleavage site. By contrast, reverting the A431V or I437V mutation in these highly evolved sequences had little effect on RC. Mutations in the NC-SP2-p6 region of Gag can be dually selected as compensatory and as direct PI resistance mutations, with cleavage at the NC-SP2 site behaving as a rate-limiting step in PI resistance. Further compensatory mutations render viral RC independent of the A431V or I437V mutations while their effect on resistance persists.
Interpretation of the increase in certain inflammatory markers in virally suppressed HIV-infected individuals must rely on an appropriate uninfected control group well characterized for ...non-HIV-related factors that contribute to chronic inflammation, e.g. smoking, alcohol consumption, or being overweight. We compared the inflammatory profiles of HIV-infected participants under long-term antiretroviral therapy (ART) with those of two HIV-uninfected groups with contrasting health behaviours.
We studied 150 HIV-infected participants (42 women, 108 men) under long-term ART (median, 6 years) followed in the ANRS PRIMO cohort since acute/early HIV-1 infection (AHI) diagnosis. Sex and age-matched controls were sampled from i) the ANRS IPERGAY pre-exposure prophylaxis trial among men at high risk for HIV infection and with high frequencies of non-HIV factors of inflammation ii) the ANRS COHVAC cohort of volunteers in vaccine trials with a low-risk profile for HIV infection. We measured the plasma levels of ten inflammatory markers.
After adjusting for smoking, alcohol use and body mass index, both HIV-infected men and women had higher levels of sCD14, sCD163, sTNFRII and I-FABP than their high-risk IPERGAY and low-risk COHVAC counterparts. Hierarchical clustering showed a subset of 15 PRIMO participants to have an inflammatory profile similar to that of most HIV-negative participants. These participants already had favourable markers at AHI diagnosis.
Long-term ART, even when initiated at a low level of immunodeficiency, fails to normalize monocyte/macrophage activation and gut epithelial dysfunction. Persistent inflammation under treatment may be related to an increased inflammatory profile since AHI.
ANRS and Paris-Saclay University.
Our study analyses the main determinants of refusal or acceptance of the 2009 A/H1N1 vaccine in patients with cystic fibrosis, a high-risk population for severe flu infection, usually very compliant ...for seasonal flu vaccine.
We conducted a qualitative study based on semi-structured interviews in 3 cystic fibrosis referral centres in Paris, France. The study included 42 patients with cystic fibrosis: 24 who refused the vaccine and 18 who were vaccinated. The two groups differed quite substantially in their perceptions of vaccine- and disease-related risks. Those who refused the vaccine were motivated mainly by the fears it aroused and did not explicitly consider the 2009 A/H1N1 flu a potentially severe disease. People who were vaccinated explained their choice, first and foremost, as intended to prevent the flu's potential consequences on respiratory cystic fibrosis disease. Moreover, they considered vaccination to be an indirect collective prevention tool. Patients who refused the vaccine mentioned multiple, contradictory information sources and did not appear to consider the recommendation of their local health care provider as predominant. On the contrary, those who were vaccinated stated that they had based their decision solely on the clear and unequivocal advice of their health care provider.
These results of our survey led us to formulate three main recommendations for improving adhesion to new pandemic vaccines. (1) it appears necessary to reinforce patient education about the disease and its specific risks, but also general population information about community immunity. (2) it is essential to disseminate a clear and effective message about the safety of novel vaccines. (3) this message should be conveyed by local health care providers, who should be involved in implementing immunization.
Limited "real life" data on raltegravir (RAL) use during pregnancy are available. Thus, we aimed at describing effectiveness and safety of RAL-based combined antiretroviral therapy (cART) in this ...setting.
HIV-1-infected women receiving RAL during pregnancy between 2008 and 2014 in ten French centers were retrospectively analysed for: (1) proportion of women receiving RAL anytime during pregnancy who achieved a plasma HIV-RNA (pVL) < 50 copies/mL at delivery, and (2) description of demographics, immuno-virological parameters and safety in women and new-borns.
We included 94 women (median age, 33 years) of which 85% originated from Sub-Saharan Africa and 16% did not have regular health insurance coverage. Sixteen women were cART-naïve (median HIV diagnosis at 30 weeks of gestation), whereas 78 were already on cART before pregnancy (40% with pVL < 50 copies/mL). RAL was initiated before pregnancy (n = 33), during the second trimester (n = 11) and the third trimester of pregnancy (n = 50). No RAL discontinuations due to adverse events were observed. Overall, at the time of delivery, pVL was < 50 copies/mL in 70% and < 400 copies/mL in 84% of women. Specifically, pVL at delivery was < 50 copies/mL in 82%, 55% and 56% of cases when RAL was started before pregnancy, during the second or third trimester of pregnancy, respectively. Median term was 38 weeks of gestation, no defect was reported and all new-borns were HIV non-infected at Month 6.
RAL appears safe and effective in this "real-life" study. No defect and no HIV transmission was reported in new-borns.
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