ABSTRACT
Importance: Chikungunya virus (CHIKV) is a mosquito-borne Alphavirus prevalent worldwide. There are currently no licensed vaccines or therapies. Objective: To evaluate the safety and tolerability of an investigational CHIKV virus-like particle (VLP) vaccine in endemic regions. Design, Setting, and Participants: This was a randomized, placebo-controlled, double-blind, phase 2 clinical trial to assess the vaccine VRC-CHKVLP059-00-VP (CHIKV VLP). The trial was conducted at 6 outpatient clinical research sites located in Haiti, Dominican Republic, Martinique, Guadeloupe, and Puerto Rico. A total of 400 healthy adults aged 18 through 60 years were enrolled after meeting eligibility criteria. The first study enrollment occurred on November 18, 2015; the final study visit, March 6, 2018. Interventions: Participants were randomized 1:1 to receive 2 intramuscular injections 28 days apart (20 µg, n = 201) or placebo (n = 199) and were followed up for 72 weeks. Main Outcomes and Measures: The primary outcome was the safety (laboratory parameters, adverse events, and CHIKV infection) and tolerability (local and systemic reactogenicity) of the vaccine, and the secondary outcome was immune response by neutralization assay 4 weeks after second vaccination. Results: Of the 400 randomized participants (mean age, 35 years; 199 [50%] women), 393 (98%) completed the primary safety analysis. All injections were well tolerated. Of the 16 serious adverse events unrelated to the study drugs, 4 (25%) occurred among 4 patients in the vaccine group and 12 (75%) occurred among 11 patients in the placebo group. Of the 16 mild to moderate unsolicited adverse events that were potentially related to the drug, 12 (75%) occurred among 8 patients in the vaccine group and 4 (25%) occurred among 3 patients in the placebo group. All potentially related adverse events resolved without clinical sequelae. At baseline, there was no significant difference between the effective concentration (EC50)-which is the dilution of sera that inhibits 50% infection in viral neutralization assay-geometric mean titers (GMTs) of neutralizing antibodies of the vaccine group (46; 95% CI, 34-63) and the placebo group (43; 95% CI, 32-57). Eight weeks following the first administration, the EC50 GMT in the vaccine group was 2005 (95% CI, 1680-2392) vs 43 (95% CI, 32-58; P < .001) in the placebo group. Durability of the immune response was demonstrated through 72 weeks after vaccination. Conclusions and Relevance: Among healthy adults in a chikungunya endemic population, a virus-like particle vaccine compared with placebo demonstrated safety and tolerability. Phase 3 trials are needed to assess clinical efficacy. Trial Registration: ClinicalTrials.gov Identifier: NCT02562482.
Subject(s)
Chikungunya Fever/prevention & control , Chikungunya virus/immunology , Vaccines, Virus-Like Particle/adverse effects , Viral Vaccines/adverse effects , Adolescent , Adult , Antibodies, Neutralizing/blood , Chikungunya Fever/immunology , Double-Blind Method , Female , Humans , Injections, Intramuscular , Male , Middle Aged , Neutralization Tests , Vaccines, Virus-Like Particle/administration & dosage , Vaccines, Virus-Like Particle/immunology , Viral Vaccines/administration & dosage , Viral Vaccines/immunology , Young AdultABSTRACT
PURPOSE OF REVIEW: Food allergy likely arises from a complex interplay between environmental triggers and genetic susceptibility. Here, we review recent studies that have investigated the genetic pathways and mechanisms that may contribute to the pathogenesis of food allergy. RECENT FINDINGS: A heritability component of food allergy has been observed in multiple studies. A number of monogenic diseases characterized by food allergy have elucidated pathways that may be important in pathogenesis. Several population-based genetic variants associated with food allergy have also been identified. The genetic mechanisms that play a role in the development of food allergy are heterogeneous and complex. Advances in our understanding of the genetics of food allergy, and how this predisposition interacts with environmental exposures to lead to disease, will improve our understanding of the key pathways leading to food allergy and inform more effective prevention and treatment strategies.
Subject(s)
Food Hypersensitivity/genetics , Genetic Predisposition to Disease/genetics , Genetic Variation/genetics , Environmental Exposure , HumansABSTRACT
BACKGROUNDBroadly neutralizing monoclonal antibodies (bNAbs) represent a promising strategy for HIV-1 immunoprophylaxis and treatment. 10E8VLS and VRC07-523LS are bNAbs that target the highly conserved membrane-proximal external region (MPER) and the CD4-binding site of the HIV-1 viral envelope glycoprotein, respectively.METHODSIn this phase 1, open-label trial, we evaluated the safety and pharmacokinetics of 5 mg/kg 10E8VLS administered alone, or concurrently with 5 mg/kg VRC07-523LS, via s.c. injection to healthy non-HIV-infected individuals.RESULTSEight participants received either 10E8VLS alone (n = 6) or 10E8VLS and VRC07-523LS in combination (n = 2). Five (n = 5 of 8, 62.5%) participants who received 10E8VLS experienced moderate local reactogenicity, and 1 participant (n = 1/8, 12.5%) experienced severe local reactogenicity. Further trial enrollment was stopped, and no participant received repeat dosing. All local reactogenicity resolved without sequelae. 10E8VLS retained its neutralizing capacity, and no functional anti-drug antibodies were detected; however, a serum t1/2 of 8.1 days was shorter than expected. Therefore, the trial was voluntarily stopped per sponsor decision (Vaccine Research Center, National Institute of Allergy and Infectious Diseases [NIAID], NIH). Mechanistic studies performed to investigate the underlying reason for the reactogenicity suggest that multiple mechanisms may have contributed, including antibody aggregation and upregulation of local inflammatory markers.CONCLUSION10E8VLS resulted in unexpected reactogenicity and a shorter t1/2 in comparison with previously tested bNAbs. These studies may facilitate identification of nonreactogenic second-generation MPER-targeting bNAbs, which could be an effective strategy for HIV-1 immunoprophylaxis and treatment.TRIAL REGISTRATIONClinicaltrials.gov, accession no. NCT03565315.FUNDINGDivision of Intramural Research, National Institute of Allergy and Infectious Diseases, NIH.
Subject(s)
HIV Infections , HIV Seropositivity , HIV-1 , Humans , HIV Infections/drug therapy , HIV Infections/prevention & control , HIV Antibodies , Broadly Neutralizing Antibodies/pharmacology , Antibodies, Monoclonal/pharmacologyABSTRACT
Individuals with food allergy are at risk for accidental exposures, potentially resulting in allergic reactions that may cause significant morbidity and mortality. Dining out, including restaurants or take-out, account for a large proportion of severe reactions. Errors due to gaps in knowledge or miscommunication can easily occur on behalf of food-allergic individuals or restaurant staff, resulting in accidental exposures and allergic reactions. Improved legislation, training of restaurant staff, and practitioner-guided education are recommended to reinforce patient safety and prevent severe allergic reactions. This Work Group Report provides guidance with specific practices that practitioners may recommend, and that patients and restaurant staff may employ, for prevention and treatment of food-allergic reactions in restaurants.