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1.
BMC Infect Dis ; 23(1): 345, 2023 May 23.
Article in English | MEDLINE | ID: mdl-37221466

ABSTRACT

BACKGROUND: The four co-circulating and immunologically interactive dengue virus serotypes (DENV1-4) pose a unique challenge to vaccine design because sub-protective immunity can increase the risk of severe dengue disease. Existing dengue vaccines have lower efficacy in DENV seronegative individuals but higher efficacy in DENV exposed individuals. There is an urgent need to identify immunological measures that are strongly associated with protection against viral replication and disease following sequential exposure to distinct serotypes. METHODS/DESIGN: This is a phase 1 trial wherein healthy adults with neutralizing antibodies to zero (seronegative), one non-DENV3 (heterotypic), or more than one (polytypic) DENV serotype will be vaccinated with the live attenuated DENV3 monovalent vaccine rDEN3Δ30/31-7164. We will examine how pre-vaccine host immunity influences the safety and immunogenicity of DENV3 vaccination in a non-endemic population. We hypothesize that the vaccine will be safe and well tolerated, and all groups will have a significant increase in the DENV1-4 neutralizing antibody geometric mean titer between days 0 and 28. Compared to the seronegative group, the polytypic group will have lower mean peak vaccine viremia, due to protection conferred by prior DENV exposure, while the heterotypic group will have higher mean peak viremia, due to mild enhancement. Secondary and exploratory endpoints include characterizing serological, innate, and adaptive cell responses; evaluating proviral or antiviral contributions of DENV-infected cells; and immunologically profiling the transcriptome, surface proteins, and B and T cell receptor sequences and affinities of single cells in both peripheral blood and draining lymph nodes sampled via serial image-guided fine needle aspiration. DISCUSSION: This trial will compare the immune responses after primary, secondary, and tertiary DENV exposure in naturally infected humans living in non-endemic areas. By evaluating dengue vaccines in a new population and modeling the induction of cross-serotypic immunity, this work may inform vaccine evaluation and broaden potential target populations. TRIAL REGISTRATION: NCT05691530 registered on January 20, 2023.


Subject(s)
Dengue Vaccines , Severe Dengue , Adult , Humans , Viremia , Vaccines, Attenuated , Vaccination , Antibodies, Neutralizing
2.
J Infect Dis ; 225(4): 715-722, 2022 02 15.
Article in English | MEDLINE | ID: mdl-34423369

ABSTRACT

BACKGROUND: Preclinical animal studies and retrospective human studies suggest that adult females have worse outcomes from influenza than males. Prospective studies in humans are missing. METHODS: Data from 164 healthy volunteers who underwent influenza A/California/04/2009/H1N1 challenge were compiled to compare differences between sexes. Baseline characteristics, including hormone levels, hemagglutination inhibition (HAI) titers, neuraminidase inhibition (NAI) titers, and outcomes after challenge were compared. Linear and logistic regression models were built to determine significant predictor variables with respect to outcomes of interest. RESULTS: HAI titers were similar between the sexes, but NAI titers were higher in males than females at 4 weeks and 8 weeks postchallenge. Females were more likely to have symptoms (mean, 0.96 vs 0.80; P = .003) and to have a higher number of symptoms (median, 3 vs 4; P = .011) than males. Linear and logistic regression models showed that prechallenge NAI titers, but not HAI titers or sex hormone levels, were predictive of all shedding and symptom outcomes of interest. CONCLUSIONS: Females in our cohorts were more likely to be symptomatic and to have a higher number of symptoms than males. NAI titers predicted all outcomes of interest and may explain differential outcomes between the sexes.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza Vaccines , Influenza, Human , Animals , Antibodies, Viral , Female , Hemagglutination Inhibition Tests , Humans , Influenza, Human/epidemiology , Male , Neuraminidase , Prospective Studies , Retrospective Studies , Sex Characteristics
3.
Antimicrob Agents Chemother ; 66(7): e0030822, 2022 07 19.
Article in English | MEDLINE | ID: mdl-35699443

ABSTRACT

Candida albicans causes debilitating, often azole-resistant, infections in patients with chronic mucocutaneous candidiasis (CMC). Amphotericin B (AMB) resistance is rare, but AMB use is limited by parenteral administration and nephrotoxicity. In this study, we evaluated cochleated AMB (CAMB), a new oral AMB formulation, in mouse models of oropharyngeal candidiasis (OPC) and vulvovaginal candidiasis (VVC) and in patients with azole-resistant CMC. OPC and VVC were modeled in Act1-/- mice, and mucosal tissue fungal burden was assessed after once-daily treatment with CAMB, vehicle, or AMB-deoxycholate (AMB-d). Four patients with azole-resistant CMC enrolled in a phase 2 CAMB dose-escalation study. The primary endpoint was clinical improvement at 2 weeks followed by optional extension for long-term CMC suppression to assess safety and efficacy. CAMB-treated mice had significantly reduced tongue and vaginal fungal burdens compared to vehicle-treated mice and exhibited comparable fungal burden reduction relative to AMB-d-treated mice. All CAMB-treated patients reached clinical efficacy by 2 weeks, three at 400 mg twice daily and one at 200 mg twice-daily dosing. All patients continued to the extension phase, with three having sustained clinical improvement of OPC and esophageal candidiasis (EC) for up to 60 months. One patient had a relapse of esophageal symptoms at week 24 and was withdrawn from further study. Clinical responses were not seen for onychomycosis or VVC. CAMB was safe and well-tolerated, without any evidence of nephrotoxicity. In summary, oral CAMB reduced tongue and vaginal fungal burdens during murine candidiasis. A proof-of-concept clinical trial in human CMC showed efficacy with good tolerability and safety. This study has been registered at ClinicalTrials.gov under identifier NCT02629419.


Subject(s)
Amphotericin B , Candidiasis, Chronic Mucocutaneous , Candidiasis , Amphotericin B/adverse effects , Animals , Antifungal Agents/adverse effects , Azoles , Candida albicans , Candidiasis/drug therapy , Candidiasis, Chronic Mucocutaneous/drug therapy , Candidiasis, Oral/drug therapy , Candidiasis, Vulvovaginal/drug therapy , Female , Humans , Mice
4.
J Clin Immunol ; 42(1): 108-118, 2022 01.
Article in English | MEDLINE | ID: mdl-34655400

ABSTRACT

X-linked MAGT1 deficiency with increased susceptibility to Epstein-Barr virus (EBV) infection and N-linked glycosylation defect (XMEN) disease is an inborn error of immunity caused by loss-of-function mutations in the magnesium transporter 1 (MAGT1) gene. The original studies of XMEN patients focused on impaired magnesium regulation, leading to decreased EBV-cytotoxicity and the loss of surface expression of the activating receptor "natural killer group 2D" (NKG2D) on CD8+ T cells and NK cells. In vitro studies showed that supraphysiological supplementation of magnesium rescued these defects. Observational studies in 2 patients suggested oral magnesium supplementation could decrease EBV viremia. Hence, we performed a randomized, double-blind, placebo-controlled, crossover study in 2 parts. In part 1, patients received either oral magnesium L-threonate (MLT) or placebo for 12 weeks followed by 12 weeks of the other treatment. Part 2 began with 3 days of high-dose intravenous (IV) magnesium sulfate (MgSO4) followed by open-label MLT for 24 weeks. One EBV-infected and 3 EBV-naïve patients completed part 1. One EBV-naïve patient was removed from part 2 of the study due to asymptomatic elevation of liver enzymes during IV MgSO4. No change in EBV or NKG2D status was observed. In vitro magnesium supplementation experiments in cells from 14 XMEN patients failed to significantly rescue NKG2D expression and the clinical trial was stopped. Although small, this study indicates magnesium supplementation is unlikely to be an effective therapeutic option in XMEN disease.


Subject(s)
Cation Transport Proteins , Epstein-Barr Virus Infections , Neoplasms , X-Linked Combined Immunodeficiency Diseases , CD8-Positive T-Lymphocytes , Cation Transport Proteins/genetics , Cross-Over Studies , Dietary Supplements , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/drug therapy , Epstein-Barr Virus Infections/genetics , Herpesvirus 4, Human/physiology , Humans , Magnesium/metabolism , Magnesium/therapeutic use , Neoplasms/genetics , X-Linked Combined Immunodeficiency Diseases/genetics
5.
Stat Neerl ; 76(3): 309-330, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35936973

ABSTRACT

This paper develops methods to test for associations between two variables with clustered data using a U-Statistic approach with a second-order approximation to the variance of the parameter estimate for the test statistic. The tests that are presented are for clustered versions of: Pearsons χ 2 test, the Spearman rank correlation and Kendall's τ for continuous data or ordinal data and for alternative measures of Kendall's τ that allow for ties in the data. Shih and Fay use the U-Statistic approach but only consider a first-order approximation. The first-order approximation has inflated significance level in scenarios with small sample sizes. We derive the test statistics using the second-order approximations aiming to improve the type I error rates. The method applies to data where clusters have the same number of measurements for each variable or where one of the variables may be measured once per cluster while the other variable may be measured multiple times. We evaluate the performance of the test statistics through simulation with small sample sizes. The methods are all available in the R package cluscor.

6.
J Infect Dis ; 224(12): 1995-2000, 2021 12 15.
Article in English | MEDLINE | ID: mdl-34008027

ABSTRACT

To speed the development of vaccines against SARS-CoV-2, the United States Federal Government has funded multiple phase 3 trials of candidate vaccines. A single 11-member data and safety monitoring board (DSMB) monitors all government-funded trials to ensure coordinated oversight, promote harmonized designs, and allow shared insights related to safety across trials. DSMB reviews encompass 3 domains: (1) the conduct of trials, including overall and subgroup accrual and data quality and completeness; (2) safety, including individual events of concern and comparisons by randomized group; and (3) interim analyses of efficacy when event-driven milestones are met. Challenges have included the scale and pace of the trials, the frequency of safety events related to the combined enrollment of over 100 000 participants, many of whom are older adults or have comorbid conditions that place them at independent risk of serious health events, and the politicized environment in which the trials have taken place.


Subject(s)
COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , COVID-19/prevention & control , Aged , COVID-19 Vaccines/administration & dosage , Humans , SARS-CoV-2 , United States , Vaccines
7.
J Infect Dis ; 224(9): 1509-1519, 2021 11 16.
Article in English | MEDLINE | ID: mdl-33718970

ABSTRACT

Previous herpes simplex virus type 2 (HSV-2) vaccines have not prevented genital herpes. Concerns have been raised about the choice of antigen, the type of antibody induced by the vaccine, and whether antibody is present in the genital tract where infection occurs. We reported results of a trial of an HSV-2 replication-defective vaccine, HSV529, that induced serum neutralizing antibody responses in 78% of HSV-1-/HSV-2- vaccine recipients. Here we show that HSV-1-/HSV-2- vaccine recipients developed antibodies to epitopes of several viral proteins; however, fewer antibody epitopes were detected in vaccine recipients compared with naturally infected persons. HSV529 induced antibodies that mediated HSV-2-specific natural killer (NK) cell activation. Depletion of glycoprotein D (gD)-binding antibody from sera reduced neutralizing titers by 62% and NK cell activation by 81%. HSV-2 gD antibody was detected in cervicovaginal fluid at about one-third the level of that in serum. A vaccine that induces potent serum antibodies transported to the genital tract might reduce HSV genital infection.


Subject(s)
Antibodies, Viral/blood , Herpes Genitalis/prevention & control , Herpes Simplex Virus Vaccines/administration & dosage , Herpes Simplex/prevention & control , Herpesvirus 2, Human/immunology , Viral Envelope Proteins/immunology , Viral Vaccines/administration & dosage , Epitopes , Herpes Simplex Virus Vaccines/immunology , Herpesvirus 1, Human/immunology , Humans , Immunization
8.
Clin Infect Dis ; 73(11): e4260-e4268, 2021 12 06.
Article in English | MEDLINE | ID: mdl-33211860

ABSTRACT

BACKGROUND: It is imperative to identify new targets for improved vaccines and therapeutics against influenza. One such target is the relatively conserved stalk region of the influenza A hemagglutinin (HA) surface protein. METHODS: We conducted a randomized, double-blind, phase 2, placebo-controlled trial of a monoclonal antibody that targets the HA stalk (CR6261) in a H1N1pdm09 healthy volunteer human challenge model. A single 50 mg/kg dose of CR6261 was infused 24 hours after challenge. The primary efficacy outcome was area under the curve (AUC) of viral RNA detection over time. RESULTS: Ninety-one healthy volunteers were randomized and underwent influenza challenge; 49 received CR6261 and 42 received placebo. CR6261 had no statistically significant effect on AUC (AUC, 48.56 log [copies/mL] × days, interquartile range [IQR], 202 vs AUC, 25.53 log [copies/mL] × days, IQR, 155; P = .315) and no clinically significant effect on influenza disease measures including number of symptoms, duration of symptoms, or inFLUenza Patient-Reported Outcome (FLU-PRO) scores. Preexisting anti-NA antibody titers were most predictive of reduced influenza disease. CR6261 reached a mean peak serum concentration of 1 × 106 ng/mL 15 minutes after infusion and a mean peak of 5.97 × 102 ng/mL in the nasal mucosa 2-3 days after infusion. CONCLUSIONS: The results of this study suggest that a monoclonal anti-stalk approach to prevent or treat influenza infection may be limited in efficacy. Future approaches should consider including and evaluating anti-stalk antibodies as part of a multifaceted strategy rather than as a stand-alone therapeutic. CLINICAL TRIALS REGISTRATION: NCT02371668.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza Vaccines , Influenza, Human , Antibodies, Viral , Hemagglutinin Glycoproteins, Influenza Virus , Humans , Influenza, Human/drug therapy , Influenza, Human/prevention & control
9.
Clin Infect Dis ; 73(9): e2789-e2798, 2021 11 02.
Article in English | MEDLINE | ID: mdl-33383587

ABSTRACT

BACKGROUND: Cryptococcal meningoencephalitis (CM) is a major cause of mortality in immunosuppressed patients and previously healthy individuals. In the latter, a post-infectious inflammatory response syndrome (PIIRS) is associated with poor clinical response despite antifungal therapy and negative cerebrospinal fluid (CSF) cultures. Data on effective treatment are limited. METHODS: Between March 2015 and March 2020, 15 consecutive previously healthy patients with CM and PIIRS were treated with adjunctive pulse corticosteroid taper therapy (PCT) consisting of intravenous methylprednisolone 1 gm daily for 1 week followed by oral prednisone 1 mg/kg/day, tapered based on clinical and radiological response plus oral fluconazole. Montreal cognitive assessments (MOCA), Karnofsky performance scores, magnetic resonance imaging (MRI) brain scanning, ophthalmic and audiologic exams, and CSF parameters including cellular and soluble immune responses were compared at PIIRS diagnosis and after methylprednisolone completion. RESULTS: The median time from antifungal treatment to steroid initiation was 6 weeks. The most common symptoms at PIIRS diagnosis were altered mental status and vision changes. All patients demonstrated significant improvements in MOCA and Karnofsky scores at 1 month (P < .0003), which was accompanied by improvements in CSF glucose, white blood cell (WBC) count, protein, cellular and soluble inflammatory markers 1 week after receiving corticosteroids (CS) (P < .003). All patients with papilledema and visual field deficits also exhibited improvement (P < .0005). Five out of 7 patients who underwent audiological testing demonstrated hearing improvement. Brain MRI showed significant improvement of radiological findings (P = .001). CSF cultures remained negative. CONCLUSIONS: PCT in this small cohort of PIIRS was associated with improvements in CM-related complications with minimal toxicity in the acute setting.


Subject(s)
Cryptococcus , Meningitis, Cryptococcal , Meningoencephalitis , Adrenal Cortex Hormones/therapeutic use , Antifungal Agents/therapeutic use , Fluconazole , Humans , Meningitis, Cryptococcal/drug therapy , Meningoencephalitis/drug therapy
10.
Lancet ; 395(10242): 1998-2007, 2020 06 27.
Article in English | MEDLINE | ID: mdl-32534628

ABSTRACT

BACKGROUND: In animal models, immunity to mosquito salivary proteins protects animals against mosquito-borne disease. These findings provide a rationale to vaccinate against mosquito saliva instead of the pathogen itself. To our knowledge, no vector salivary protein-based vaccine has been tested for safety and immunogenicity in humans. We aimed to assess the safety and immunogenicity of Anopheles gambiae saliva vaccine (AGS-v), a peptide-based vaccine derived from four A gambiae salivary proteins, in humans. METHODS: In this randomised, placebo-controlled, double-blind, phase 1 trial, participants were enrolled at the National Institutes of Health Clinical Center in Bethesda, MD, USA. Participants were eligible if they were healthy adults, aged 18-50 years with no history of severe allergic reactions to mosquito bites. Participants were randomly assigned (1:1:1), using block randomisation and a computer-generated randomisation sequence, to treatment with either 200 nmol of AGS-v vaccine alone, 200 nmol of AGS-v with adjuvant (Montanide ISA 51), or sterile water as placebo. Participants and clinicians were masked to treatment assignment. Participants were given a subcutaneous injection of their allocated treatment at day 0 and day 21, followed by exposure to feeding by an uninfected Aedes aegypti mosquito at day 42 to assess subsequent risk to mosquito bites in a controlled setting. The primary endpoints were safety and immunogenicity at day 42 after the first immunisation. Participants who were given at least one dose of assigned treatment were assessed for the primary endpoints and analysis was by intention to treat. The trial was registered with ClinicalTrials.gov, NCT03055000, and is closed for accrual. FINDINGS: Between Feb 15 and Sept 10, 2017, we enrolled and randomly assigned 49 healthy adult participants to the adjuvanted vaccine (n=17), vaccine alone (n=16), or placebo group (n=16). Five participants did not complete the two-injection regimen with mosquito feeding at day 42, but were included in the safety analyses. No systemic safety concerns were identified; however, one participant in the adjuvanted vaccine group developed a grade 3 erythematous rash at the injection site. Pain, swelling, erythema, and itching were the most commonly reported local symptoms and were significantly increased in the adjuvanted vaccine group compared with both other treatment groups (nine [53%] of 17 participants in the adjuvanted vaccine group, two [13%] of 16 in the vaccine only group, and one [6%] of 16 in the placebo group; p=0·004). By day 42, participants who were given the adjuvanted vaccine had a significant increase in vaccine-specific total IgG antibodies compared with at baseline than did participants who were give vaccine only (absolute difference of log10-fold change of 0·64 [95% CI 0·39 to 0·89]; p=0·0002) and who were given placebo (0·62 [0·34 to 0·91]; p=0·0001). We saw a significant increase in IFN-γ production by peripheral blood mononuclear cells at day 42 in the adjuvanted vaccine group compared with in the placebo group (absolute difference of log10 ratio of vaccine peptide-stimulated vs negative control 0·17 [95% CI 0·061 to 0·27]; p=0·009) but we saw no difference between the IFN-γ production in the vaccine only group compared with the placebo group (0·022 [-0·072 to 0·116]; p=0·63). INTERPRETATION: AGS-v was well tolerated, and, when adjuvanted, immunogenic. These findings suggest that vector-targeted vaccine administration in humans is safe and could be a viable option for the increasing burden of vector-borne disease. FUNDING: Office of the Director and the Division of Intramural Research at the National Institute of Allergy and Infectious Diseases, and National Institutes of Health.


Subject(s)
Adjuvants, Immunologic/administration & dosage , Disease Transmission, Infectious/prevention & control , Immunogenicity, Vaccine/immunology , Saliva/immunology , Adjuvants, Immunologic/adverse effects , Adult , Animals , Anopheles/immunology , Anopheles/metabolism , Case-Control Studies , Double-Blind Method , Female , Humans , Immunoglobulin G/immunology , Injections, Subcutaneous/methods , Leukocytes, Mononuclear/immunology , Male , Models, Animal , Mosquito Vectors/immunology , Mosquito Vectors/metabolism , Placebos/administration & dosage , Safety , Vaccination/adverse effects , Vaccination/methods
11.
BMC Infect Dis ; 21(1): 881, 2021 Aug 28.
Article in English | MEDLINE | ID: mdl-34454432

ABSTRACT

BACKGROUND: The introduction of Zika and chikungunya to dengue hyperendemic regions increased interest in better understanding characteristics of these infections. We conducted a cohort study in Mexico to evaluate the natural history of Zika infection. We describe here the frequency of Zika, chikungunya and dengue virus infections immediately after Zika introduction in Mexico, and baseline characteristics of participants for each type of infection. METHODS: Prospective, observational cohort evaluating the natural history of Zika virus infection in the Mexico-Guatemala border area. Patients with fever, rash or both, meeting the modified criteria of PAHO for probable Zika cases were enrolled (June 2016-July 2018) and followed-up for 6 months. We collected data on sociodemographic, environmental exposure, clinical and laboratory characteristics. Diagnosis was established based on viral RNA identification in serum and urine samples using RT-PCR for Zika, chikungunya, and dengue. We describe the baseline sociodemographic and environmental exposure characteristics of participants according to diagnosis, and the frequency of these infections over a two-year period immediately after Zika introduction in Mexico. RESULTS: We enrolled 427 participants. Most patients (n = 307, 65.7%) had an acute illness episode with no identified pathogen (UIE), 37 (8%) Zika, 82 (17.6%) dengue, and 1 (0.2%) chikungunya. In 2016 Zika predominated, declined in 2017 and disappeared in 2018; while dengue increased after 2017. Patients with dengue were more likely to be men, younger, and with lower education than those with Zika and UIE. They also reported closer contact with water sources, and with other people diagnosed with dengue. Participants with Zika reported sexual exposure more frequently than people with dengue and UIE. Zika was more likely to be identified in urine while dengue was more likely found in blood in the first seven days of symptoms; but PCR results for both were similar at day 7-14 after symptom onset. CONCLUSIONS: During the first 2 years of Zika introduction to this dengue hyper-endemic region, frequency of Zika peaked and fell over a two-year period; while dengue progressively increased with a predominance in 2018. Different epidemiologic patterns between Zika, dengue and UIE were observed. Trial registration Clinical.Trials.gov (NCT02831699).


Subject(s)
Chikungunya Fever , Dengue Virus , Dengue , Zika Virus Infection , Zika Virus , Chikungunya Fever/epidemiology , Cohort Studies , Dengue/epidemiology , Dengue Virus/genetics , Female , Humans , Male , Mexico/epidemiology , Prospective Studies , Zika Virus Infection/epidemiology
12.
Clin Infect Dis ; 71(1): 53-62, 2020 06 24.
Article in English | MEDLINE | ID: mdl-31429907

ABSTRACT

BACKGROUND: The natural history of anti-interferon-γ (IFN-γ) autoantibody-associated immunodeficiency syndrome is not well understood. METHODS: Data of 74 patients with anti-IFN-γ autoantibodies at Srinagarind Hospital, Thailand, were collected annually (median follow-up duration, 7.5 years). Annual data for 19 patients and initial data for 4 patients with anti-IFN-γ autoantibodies at the US National Institutes of Health were collected (median follow-up duration, 4.5 years). Anti-IFN-γ autoantibody levels were measured in plasma samples. RESULTS: Ninety-one percent of US patients were of Southeast Asian descent; there was a stronger female predominance (91%) in US than Thai (64%) patients. Mycobacterium abscessus (34%) and Mycobacterium avium complex (83%) were the most common nontuberculous mycobacteria in Thailand and the United States, respectively. Skin infections were more common in Thailand (P = .001), whereas bone (P < .0001), lung (P = .002), and central nervous system (P = .03) infections were more common in the United States. Twenty-four percent of Thai patients died, most from infections. None of the 19 US patients with follow-up data died. Anti-IFN-γ autoantibody levels decreased over time in Thailand (P < .001) and the United States (P = .017), with either cyclophosphamide (P = .01) or rituximab therapy (P = .001). CONCLUSIONS: Patients with anti-IFN-γ autoantibodies in Thailand and the United States had distinct demographic and clinical features. While titers generally decreased with time, anti-IFN-γ autoantibody disease had a chronic clinical course with persistent infections and death. Close long-term surveillance for new infections is recommended.


Subject(s)
Immunologic Deficiency Syndromes , Mycobacterium Infections, Nontuberculous , Mycobacterium abscessus , Autoantibodies , Female , Humans , Thailand , United States/epidemiology
13.
Clin Trials ; 17(5): 472-482, 2020 10.
Article in English | MEDLINE | ID: mdl-32674594

ABSTRACT

BACKGROUND: Endpoint choice for randomized controlled trials of treatments for novel coronavirus-induced disease (COVID-19) is complex. Trials must start rapidly to identify treatments that can be used as part of the outbreak response, in the midst of considerable uncertainty and limited information. COVID-19 presentation is heterogeneous, ranging from mild disease that improves within days to critical disease that can last weeks to over a month and can end in death. While improvement in mortality would provide unquestionable evidence about the clinical significance of a treatment, sample sizes for a study evaluating mortality are large and may be impractical, particularly given a multitude of putative therapies to evaluate. Furthermore, patient states in between "cure" and "death" represent meaningful distinctions. Clinical severity scores have been proposed as an alternative. However, the appropriate summary measure for severity scores has been the subject of debate, particularly given the variable time course of COVID-19. Outcomes measured at fixed time points, such as a comparison of severity scores between treatment and control at day 14, may risk missing the time of clinical benefit. An endpoint such as time to improvement (or recovery) avoids the timing problem. However, some have argued that power losses will result from reducing the ordinal scale to a binary state of "recovered" versus "not recovered." METHODS: We evaluate statistical power for possible trial endpoints for COVID-19 treatment trials using simulation models and data from two recent COVID-19 treatment trials. RESULTS: Power for fixed time-point methods depends heavily on the time selected for evaluation. Time-to-event approaches have reasonable statistical power, even when compared with a fixed time-point method evaluated at the optimal time. DISCUSSION: Time-to-event analysis methods have advantages in the COVID-19 setting, unless the optimal time for evaluating treatment effect is known in advance. Even when the optimal time is known, a time-to-event approach may increase power for interim analyses.


Subject(s)
Antiviral Agents/therapeutic use , Betacoronavirus , Coronavirus Infections/drug therapy , Pneumonia, Viral/drug therapy , Randomized Controlled Trials as Topic/methods , COVID-19 , Coronavirus Infections/epidemiology , Humans , Pandemics , Pneumonia, Viral/epidemiology , SARS-CoV-2
14.
J Infect Dis ; 220(6): 990-1000, 2019 08 09.
Article in English | MEDLINE | ID: mdl-31058977

ABSTRACT

BACKGROUND: Herpes simplex virus 2 (HSV2) causes genital herpes in >400 million persons worldwide. METHODS: We conducted a randomized, double-blinded, placebo-controlled trial of a replication-defective HSV2 vaccine, HSV529. Twenty adults were enrolled in each of 3 serogroups of individuals: those negative for both HSV1 and HSV2 (HSV1-/HSV2-), those positive or negative for HSV1 and positive for HSV2 (HSV1±/HSV2+), and those positive for HSV1 and negative for HSV2 (HSV1+/HSV2-). Sixty participants received vaccine or placebo at 0, 1, and 6 months. The primary end point was the frequency of solicited local and systemic reactions to vaccination. RESULTS: Eighty-nine percent of vaccinees experienced mild-to-moderate solicited injection site reactions, compared with 47% of placebo recipients (95% confidence interval [CI], 12.9%-67.6%; P = .006). Sixty-four percent of vaccinees experienced systemic reactions, compared with 53% of placebo recipients (95% CI, -17.9% to 40.2%; P = .44). Seventy-eight percent of HSV1-/HSV2- vaccine recipients had a ≥4-fold increase in neutralizing antibody titer after 3 doses of vaccine, whereas none of the participants in the other serogroups had such responses. HSV2-specific CD4+ T-cell responses were detected in 36%, 46%, and 27% of HSV1-/HSV2-, HSV1±/HSV2+, and HSV1+/HSV2- participants, respectively, 1 month after the third dose of vaccine, and CD8+ T-cell responses were detected in 14%, 8%, and 18% of participants, respectively. CONCLUSIONS: HSV529 vaccine was safe and elicited neutralizing antibody and modest CD4+ T-cell responses in HSV-seronegative vaccinees. CLINICAL TRIALS REGISTRATION: NCT01915212.


Subject(s)
Herpes Genitalis/prevention & control , Herpes Simplex/prevention & control , Herpesvirus 2, Human/immunology , Vaccination , Viral Vaccines/administration & dosage , Viral Vaccines/immunology , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , CD4-Positive T-Lymphocytes , CD8-Positive T-Lymphocytes , Double-Blind Method , Female , Herpes Genitalis/immunology , Herpes Simplex/immunology , Herpesvirus 1, Human/immunology , Humans , Male , Neutralization Tests , Viral Vaccines/therapeutic use , Young Adult
15.
Clin Infect Dis ; 69(11): 1903-1911, 2019 11 13.
Article in English | MEDLINE | ID: mdl-30753384

ABSTRACT

BACKGROUND: Effective therapeutics for respiratory viruses are needed. Early data suggest that nitazoxanide (NTZ) may be beneficial for treating acute respiratory viral illness. METHODS: From March 2014 through March 2017, a double-blind, placebo-controlled trial was conducted in 260 participants ≥1 year old hospitalized with influenza-like illness at 6 hospitals in Mexico. Participants were randomized 1:1 to NTZ (age ≥12 years, 600 mg twice daily; age 4-11 years and 1-3 years, 200 or 100 mg twice daily, respectively) or placebo for 5 days in addition to standard of care. The primary endpoint was time from first dose to hospital discharge. Influenza reverse-transcription polymerase chain reaction and Respifinder 22 multiplex test were used for virus detection. RESULTS: Of 260 participants enrolled, 257 were randomized and took at least 1 dose of study treatment (intention-to-treat population): 130 in the NTZ group and 127 in the placebo group. The Kaplan-Meier estimate of the median duration of hospitalization was 6.5 (interquartile range [IQR], 4.0-9.0) days in the NTZ group vs 7.0 (IQR, 4.0-9.0) days in the placebo group (P = .56). Duration of hospitalization between the 2 treatments was similar in children (P = .29) and adults (P = .62), influenza A and B (P = .32), and other respiratory viruses. Seven (5.4%) and 6 (4.7%) participants in the NTZ and placebo groups, respectively, reported serious adverse events. CONCLUSIONS: Treatment with NTZ did not reduce the duration of hospital stay in severe influenza-like illness. Further analyses based on age and evaluations by virus did not reveal any subgroups that appeared to benefit from NTZ. CLINICAL TRIALS REGISTRATION: NCT02057757.


Subject(s)
Antiviral Agents/therapeutic use , Severe Acute Respiratory Syndrome/drug therapy , Thiazoles/therapeutic use , Adolescent , Adult , Aged , Antiviral Agents/adverse effects , Child , Child, Preschool , Double-Blind Method , Female , Hospitalization , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Nitro Compounds , Oseltamivir/adverse effects , Oseltamivir/therapeutic use , Severe Acute Respiratory Syndrome/virology , Thiazoles/adverse effects , Treatment Outcome , Young Adult , Zanamivir/adverse effects , Zanamivir/therapeutic use
16.
J Allergy Clin Immunol ; 141(1): 365-371, 2018 01.
Article in English | MEDLINE | ID: mdl-28528201

ABSTRACT

BACKGROUND: Chronic granulomatous disease (CGD) is characterized by recurrent life-threatening bacterial and fungal infections and aberrant inflammation. Mutations in CYBB cause X-linked CGD and account for 65% to 70% of cases in Western countries. OBJECTIVE: We sought to understand the clinical manifestations associated with the X-linked CGD carrier state. METHODS: We undertook a comprehensive retrospective study of 162 affected female subjects. We examined dihydrorhodamine 123 (DHR) oxidation data for percentage of X-chromosome inactivation. We correlated lyonization (%DHR+) with clinical features. Where possible, we followed %DHR+ values over time. RESULTS: Clinical data were available for 93 female subjects: %DHR+ values were 46% (mean) and 47% (median; SD, 24). Using the %DHR+ value as the criterion for X inactivation, 78% of patients had levels of inactivation of 20% to 80%, suggesting random inactivation that was independent of age. In contrast, carriers with CGD-type infections had median %DHR+ values of 8% (n = 14; range, 0.06% to 48%), and those with only autoimmune or inflammatory manifestations had median %DHR+ values of 39% (n = 31; range, 7.4% to 74%). Those with both infections and autoimmunity had low %DHR+ values (n = 6; range, 3% to 14%). A %DHR+ value of less than 10% was strongly associated with infections (odds ratio, 99). Strong association persisted when %DHR+ values were less than 20% (odds ratio, 12). Autoimmunity was not associated with %DHR+ values. In 2 sets of identical twins, the %DHR+ populations tracked closely over time. Although the %DHR+ populations were very similar between sisters, those between mothers and daughters were unrelated. CONCLUSIONS: A low %DHR+ value strongly predicts infection risk in X-linked CGD carriers, and the carrier state itself is associated with autoimmunity.


Subject(s)
Genes, X-Linked , Genetic Association Studies , Granulomatous Disease, Chronic/diagnosis , Granulomatous Disease, Chronic/genetics , Heterozygote , Phenotype , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers , Child , Child, Preschool , Female , Granulomatous Disease, Chronic/complications , Granulomatous Disease, Chronic/immunology , Humans , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Infant , Infections/etiology , Middle Aged , Mutation , Odds Ratio , Symptom Assessment , X Chromosome Inactivation , Young Adult
18.
Clin Trials ; 14(3): 264-276, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28397569

ABSTRACT

Background/Aims A single best endpoint for evaluating treatments of severe influenza requiring hospitalization has not been identified. A novel six-category ordinal endpoint of patient status is being used in a randomized controlled trial (FLU-Intravenous Immunoglobulin - FLU-IVIG) of intravenous immunoglobulin. We systematically examine four factors regarding the use of this ordinal endpoint that may affect power from fitting a proportional odds model: (1) deviations from the proportional odds assumption which result in the same overall treatment effect as specified in the FLU-IVIG protocol and which result in a diminished overall treatment effect, (2) deviations from the distribution of the placebo group assumed in the FLU-IVIG design, (3) the effect of patient misclassification among the six categories, and (4) the number of categories of the ordinal endpoint. We also consider interactions between the treatment effect (i.e. factor 1) and each other factor. Methods We conducted a Monte Carlo simulation study to assess the effect of each factor. To study factor 1, we developed an algorithm for deriving distributions of the ordinal endpoint in the two treatment groups that deviated from proportional odds while maintaining the same overall treatment effect. For factor 2, we considered placebo group distributions which were more or less skewed than the one specified in the FLU-IVIG protocol by adding or subtracting a constant from the cumulative log odds. To assess factor 3, we added misclassification between adjacent pairs of categories that depend on subjective patient/clinician assessments. For factor 4, we collapsed some categories into single categories. Results Deviations from proportional odds reduced power at most from 80% to 77% given the same overall treatment effect as specified in the FLU-IVIG protocol. Misclassification and collapsing categories can reduce power by over 40 and 10 percentage points, respectively, when they affect categories with many patients and a discernible treatment effect. But collapsing categories that contain no treatment effect can raise power by over 20 percentage points. Differences in the distribution of the placebo group can raise power by over 20 percentage points or reduce power by over 40 percentage points depending on how patients are shifted to portions of the ordinal endpoint with a large treatment effect. Conclusion Provided that the overall treatment effect is maintained, deviations from proportional odds marginally reduce power. However, deviations from proportional odds can modify the effect of misclassification, the number of categories, and the distribution of the placebo group on power. In general, adjacent pairs of categories with many patients should be kept separate to help ensure that power is maintained at the pre-specified level.


Subject(s)
Hospitalization/statistics & numerical data , Influenza, Human/therapy , Monte Carlo Method , Randomized Controlled Trials as Topic , Algorithms , Data Interpretation, Statistical , Humans , Immunoglobulins, Intravenous/therapeutic use , Proportional Hazards Models , Severity of Illness Index , Treatment Outcome
19.
Ann Allergy Asthma Immunol ; 116(5): 402-7, 2016 05.
Article in English | MEDLINE | ID: mdl-27052815

ABSTRACT

BACKGROUND: Patients with chronic inflammatory lung diseases, such as asthma, are at higher risk for influenza-like illness (ILI) complications. Viral infections are known to trigger asthma exacerbations, but a thorough description of the clinical characteristics of ILI-associated asthma exacerbations and the role of viruses as a risk factor for severe exacerbation (SE) in ILI has not been published yet. OBJECTIVE: To investigate risk factors for SE in patients with ILI and asthma. METHODS: Patients with ILI symptoms were recruited from 6 hospitals of Mexico (LaRed sites) during 2010 to 2014. Those with a previous asthma diagnosis and ILI symptoms and who were 5 years or older were included. Patients were assigned as cases or controls based on symptoms reported. SE was defined when participants presented with wheezing or dyspnea and required hospitalization. RESULTS: A total of 486 patients with ILI and a diagnosis of asthma were included. There were no differences in the proportion, number, or type of viral illness among those with and without SE. Those with SE were less likely to report ILI symptoms. Muscle pain and nasal drip were predictors for patients not progressing to SE. A delay in seeking medical care was associated with SE (odds ratio, 2.93; 95% CI, 1.46-5.88). CONCLUSION: The presence of a particular virus did not predict SE. ILI symptoms in asthma patients are not associated with severe exacerbation. Patients with asthma should be encouraged to seek early medical care when ILI symptoms are first noticed to prevent serious complications.


Subject(s)
Asthma/epidemiology , Virus Diseases/epidemiology , Adolescent , Child , Child, Preschool , Female , Hospitalization , Humans , Male , Mexico/epidemiology , Odds Ratio , Risk Factors , Severity of Illness Index
20.
BMC Infect Dis ; 16: 269, 2016 06 10.
Article in English | MEDLINE | ID: mdl-27287374

ABSTRACT

BACKGROUND: Health care associated transmission of Mycobacterium tuberculosis (TB) is well described. A previous survey of infection control (IC) practices at clinical research sites in low and middle income countries (LMIC) funded by the National Institute of Allergy and Infectious Diseases (NIAID) conducting HIV research identified issues with respiratory IC practices. A guideline for TB IC based on international recommendations was developed and promulgated. This paper reports on adherence to the guideline at sites conducting or planning to conduct TB studies with the intention of supporting improvement. METHODS: A survey was developed that assessed IC activities in three domains: facility level measures, administrative control measures and environmental measures. An external site monitor visited each site in 2013-2014, to complete the audit. A central review committee evaluated the site-level survey and results were tabulated. Fisher's exact test was performed to determine whether there were significant differences in practices at sites that had IC officers versus sites that did not have IC officers. Significance was assessed at p

Subject(s)
Developing Countries , Guideline Adherence/statistics & numerical data , Infection Control/methods , Tuberculosis/prevention & control , Clinical Trials as Topic , Facility Design and Construction , Hand Disinfection , Health Personnel , Humans , Infection Control/organization & administration , Infection Control/standards , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Masks , Mass Screening , Mycobacterium tuberculosis , National Institute of Allergy and Infectious Diseases (U.S.) , Practice Guidelines as Topic , Surveys and Questionnaires , Tuberculosis/diagnosis , United States , Ventilation
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