Live-Attenuated Respiratory Syncytial Virus Vaccine Candidate With Deletion of RNA Synthesis Regulatory Protein M2-2 is Highly Immunogenic in Children.

Background: Live respiratory syncytial virus (RSV) candidate vaccine LIDΔM2-2 is attenuated by deletion of the RSV RNA regulatory protein M2-2, resulting in upregulated viral gene transcription and antigen expression but reduced RNA replication. Methods: RSV-seronegative children ages 6-24 months received a single intranasal dose of 105 plaque forming units (PFU) of LIDΔM2-2 (n = 20) or placebo (n = 9) (NCT02237209, NCT02040831). RSV serum antibodies, vaccine infectivity, and reactogenicity were assessed. During the following RSV season, participants were monitored for respiratory illness and pre- and post-RSV season serum antibodies. Results: Vaccine virus was shed by 95% of vaccinees (median peak titers of 3.8 log10 PFU/mL by quantitative culture and 6.3 log10 copies/mL by PCR); 90% had ≥4-fold rise in serum neutralizing antibodies. Respiratory symptoms and fever were common in vaccine (95%) and placebo (78%). One vaccinee had grade 2 rhonchi concurrent with vaccine shedding, rhinovirus, and enterovirus. Eight of 19 vaccinees versus 2 of 9 placebo recipients had substantially increased RSV antibody titers after the RSV season without medically attended RSV disease, indicating anamnestic vaccine responses to wild-type RSV without significant illness. Conclusion: LIDΔM2-2 had excellent infectivity and immunogenicity, encouraging further study of vaccine candidates attenuated by M2-2 deletion. Clinical Trials Registration: NCT02237209, NCT02040831.

Safety and efficacy of antibiotics among acutely decompensated cirrhosis patients.

BACKGROUND AND AIM: Infection is a leading precipitant of acute-on-chronic liver failure. This study aims to determine the safety and efficacy of antibiotics within acute-on-chronic liver failure. METHODS: Retrospective study of 457 acute-on-chronic liver failure patients admitted to the University of Arizona Health Network between January 1 and December 31, 2014. Eligibility criteria were as follows: at least 18 years of age and 6 months follow-up, data available to calculate systemic inflammatory response syndrome (SIRS), and acute-on-chronic liver failure. This study collected patient's clinical features and historical data. Key data points were infection, antibiotic use, and SIRS. This study used Cox proportional hazards to model the effects of clinical factors on risk of death. RESULTS: A total of 521 of 1243 met the inclusion criteria, and 64 had missing data, leaving 457 patients. Infection resulted in higher hazard (hazard ratio [HR] = 1.6, confidence interval [CI]: 1.1-1.3, P = 0.01). Patients with infections and antibiotics, compared with non-infected patients without antibiotics, had higher hazard (HR = 1.633, CI: 1.022-2.609, P = .04). Of those infected patients with antibiotics, SIRS patients experienced higher hazard (HR = 1.9, CI: 1.1-3.0, P = .007). Multivariable Cox proportional hazards associated the following with higher hazard: SIRS (HR = 1.866, CI: 1.242-2.804, P = 0.003), vancomycin (HR = 1.640, CI: 1.119-2.405, P = 0.011), Model for End-Stage Liver Disease (HR = 1.051, CI: 1.030-1.073, P < 0.001), gastrointestinal bleeding (HR = 1.727, CI: 1.180-2.527, P = 0.005), and hepatic encephalopathy (HR = 1.807, CI: 1.247-2.618, P = 0.002). CONCLUSION: Overall, treatment of infection with antibiotics did not improve survival; however, patients not meeting SIRS criteria had better outcomes, and vancomycin was associated with poorer survival among acute-on-chronic liver failure patients.

Retinol Binding Protein, Sunlight Hours, and the Influenza Virus-Specific Immune Response.

Healthy pediatric immune responses depend on adequate vitamin A and D levels. Relationships between solar ultraviolet B (UVB) radiation and vitamin D are well understood, while relationships between sunlight, vitamin A, and its serum escort, retinol binding protein (RBP), are not. A pediatric clinical study enrolled 2-8-year-old children at various times between September 2016 and March 2017, inclusive, in Memphis, Tennessee. A serum sample from each child was then assayed to examine the influence of season on vitamin levels. We found that RBP and RBP/retinol molar ratios decreased in winter months and RBP/retinol ratios correlated positively with the average daily sunlight hours per month. A food frequency questionnaire given to parents/guardians indicated a shift in dietary intake from plant-based foods to animal-based foods by children between winter and spring months. This translated to higher retinol and zinc (integral to RBP-transthyretin-retinol complexes) in the spring, perhaps explaining the seasonal influence on RBP/retinol. RBP and retinol were associated positively with IgG/IgM and IgA/IgM ratios. RBP and retinol, but not 25(OH)D, also correlated positively with influenza virus-specific antibodies. Retinol correlated negatively, while 25(OH)D correlated positively, with certain serum cytokine/chemokine levels. Significant differences in 25(OH)D, immunoglobulin ratios, and cytokines/chemokines were observed between black and white children. In sum, seasonal changes in dietary foods rich in retinol and zinc may have influenced RBP levels, which in turn influenced innate and adaptive immune responses. Results encourage routine monitoring and reporting of season, RBP, and vitamin levels in future clinical studies, as seasons may affect sunlight exposures, diet, vitamin levels, and immune protection against infectious disease.

High Rates of Viral Suppression and Care Retention Among Youth Born Outside of the United States with Perinatally Acquired HIV.

BACKGROUND: Youth born outside of the US with perinatally acquired HIV infection (YBoUS-PHIV) account for most children living with HIV in the US, but there are few data characterizing their care outcomes. METHODS: We conducted a retrospective study of YBoUS-PHIV receiving care across 3 HIV clinics in the Southeastern US between October 2018 and 2019. Primary outcomes were retention in care and viral suppression defined as (1) proportion of suppressed viral loads (VLs) and (2) having all VLs suppressed (definition 1 presented in the abstract). Primary predictors were age, adoption and disclosure status (full, partial and none/unknown). Multivariable logistic regression and χ 2 tests were used to test for associations with care outcomes. Analysis of disclosure status was restricted to youth greater than or equal to 12 years. RESULTS: The cohort included 111 YBoUS-PHIV. Median age was 14 years (interquartile range, 12-18), 59% were female, and 79% were international adoptees. Overall, 84% of patients were retained in care, and 88% were virally suppressed at each VL measurement. Adopted youth were more likely to be virally suppressed than nonadopted youth [odds ratio (OR), 7.08; P < 0.01] although the association was not statistically significant in adjusted analysis (adjusted OR, 4.26; P = 0.07). Neither age nor adoption status was significantly associated with retention. Among 89 patients greater than or equal to 12 years, 74% were fully disclosed of their HIV status, 12% were partially disclosed, and 13% had not started the disclosure process. There was no significant difference in retention or viral suppression by disclosure status. CONCLUSIONS: YBoUS-PHIV achieved high rates of retention and viral suppression. Adopted youth may be more likely to achieve viral suppression which may reflect the need for tailored interventions for nonadopted youth.

Combining SJ733, an oral ATP4 inhibitor of Plasmodium falciparum, with the pharmacokinetic enhancer cobicistat: An innovative approach in antimalarial drug development.

BACKGROUND: SJ733, a newly developed inhibitor of P. falciparum ATP4, has a favorable safety profile and rapid antiparasitic effect but insufficient duration to deliver a single-dose cure of malaria. We investigated the safety, tolerability, and pharmacokinetics of a multidose SJ733 regimen and a single-dose pharmacoboost approach using cobicistat to inhibit CYP3A4, thereby increasing exposure. METHODS: Two multidose unboosted cohorts (n = 9) (SJ733, 300 mg and 600 mg daily for 3 days) followed by three single-dose boosted cohorts combining SJ733 (n = 18) (75-, 300-, or 600-mg single dose) with cobicistat (150-mg single dose) as a pharmacokinetic booster were evaluated in healthy volunteers (ClinicalTrials.gov: NCT02661373). FINDINGS: All participants tolerated SJ733 well, with no serious adverse events (AEs), dose-limiting toxicity, or clinically significant electrocardiogram or laboratory test findings. All reported AEs were Grade 1, clinically insignificant, and considered unlikely or unrelated to SJ733. Compared to unboosted cohorts, the SJ733/cobicistat-boosted cohorts showed a median increase in area under the curve and maximum concentration of 3·9 × and 2·6 ×, respectively, and a median decrease in the ratio of the major CYP3A-produced metabolite SJ506 to parent drug of 4·6 × . Incorporating these data in a model of parasite dynamics indicated that a 3-day regimen of SJ733/cobicistat (600 mg/150 mg daily) relative to a single 600-mg dose ± cobicistat would increase parasite clearance from 106 to 1012 parasites/µL. INTERPRETATION: The multidose and pharmacoboosted approaches to delivering SJ733 were well-tolerated and significantly increased drug exposure and prediction of cure. This study supports the further development of SJ733 and demonstrates an innovative pharmacoboost approach for an antimalarial. FUNDING: Global Health Innovative Technology Fund, Medicines for Malaria Venture, National Institutes of Health, and American Lebanese Syrian Associated Charities.

Month of Influenza Virus Vaccination Influences Antibody Responses in Children and Adults.

The improvement of influenza virus vaccines and the development of a universal product have been long-standing goals in pre-clinical and clinical research. To meet these goals and to understand the strengths and weaknesses of current vaccine strategies, scientists routinely study human responses toward seasonal influenza vaccines. This research is frequently performed with clinical samples taken throughout an influenza season, often without strict attention to the month of inoculation for each study participant. Here, we ask how the timing of vaccination affects outcomes. Results demonstrate significant influences of inoculation month on the immune response. During the progression from fall to winter months, there are changes in host lifestyles and in the frequencies of clinical/sub-clinical viral infections that can significantly alter vaccine immunogenicity. We now recommend routine assessment of inoculation month during clinical studies to inform data interpretation and expedite the development of successful vaccines. This recommendation is pertinent to numerous vaccine development efforts within and outside the influenza virus field.

Rapid Start of Antiretroviral Therapy in Youth Diagnosed with HIV Infection.

BACKGROUND: Guidelines for the use of antiretroviral agents in adults and adolescents with HIV recommend that antiretroviral therapy (ART) be started as soon as possible. While rapid initiation of ART in adults with HIV has been well-described, there is relatively little information describing this approach for youth. METHODS: On April 1, 2018, St. Jude Children's Research Hospital began offering ART to youth with HIV infection at their first clinic visit. We report the results of a quality improvement initiative that compared patients who offered ART at their first visit to a historical cohort of patients who initiated ART at a subsequent visit. Demographic, HIV biomarker, and visit information were abstracted from medical records, described and compared using univariate statistical methods. RESULTS: There were 124 ART-naive youth (median age 19 years, 91% male, 94% black) first seen during the indicated time period. A total of 54 patients were in the baseline cohort and 70 patients were in the rapid start cohort. 90% of youth in the rapid start cohort started ART on their first clinic visit. Time from first clinic visit to undetectable viral load was significantly higher in the baseline cohort compared with the rapid start cohort (median 54 vs. 41 days; P = 0.01). Retention in care 12 months following the first clinic visit was comparable and overall high (>80%). CONCLUSIONS: Starting ART-naïve youth with HIV infection on ART at their first clinic visit is feasible, has high acceptance, leads to faster viral load suppression, and is associated with high retention in care.

Preventing Medication Nonadherence of Youth (13-24 Years) With HIV Initiating Antiretroviral Therapy.

PURPOSE: The objective of this study was to evaluate the feasibility and acceptability of a dynamic, behavioral intervention to optimize medication adherence of adolescents and young adults (AYAs) with HIV newly initiating highly active antiretroviral therapy (HAART) and explore its efficacy on adherence and disease outcomes. METHODS: The two-arm randomized controlled trial piloted a brief, individualized intervention designed for direct integration into standard clinical care. In total, 32 AYAs with a confirmed HIV diagnosis, reportedly horizontally acquired, and recommended to initiate HAART completed a two-week placebo trial before HAART initiation and were subsequently randomized to standard of care or the individualized intervention. Adherence and disease outcomes were measured over the first six months of HAART. RESULTS: Results supported the primary study aim regarding feasibility (recruitment = 89%, attendance = 81%-100%, intervention exercise completion = 100%) and acceptability (average favorable response = 89%). Data also supported the positive effect of the intervention on select HAART adherence measures and disease outcomes. Adherence (by pharmacy refill) declined in both groups; however, adherence declined more slowly in the intervention group versus standard of care (p < .001). In addition, 100% of participants receiving the intervention obtained an undetectable viral load by 3 months and maintained an undetectable viral load at 6 months (vs. 68.8% standard of care). CONCLUSIONS: This is one of the first interventions to target adherence for AYAs with HIV newly initiating HAART and designed for delivery in existing clinical care settings. Future research will help confirm efficacy and the potential utility of the intervention in promoting HAART adherence from medication initiation and preventing the decrease in adherence often observed over time.

Safety, tolerability, pharmacokinetics, and antimalarial efficacy of a novel Plasmodium falciparum ATP4 inhibitor SJ733: a first-in-human and induced blood-stage malaria phase 1a/b trial.

BACKGROUND: (+)-SJ000557733 (SJ733) is a novel, orally bioavailable inhibitor of Plasmodium falciparum ATP4. In this first-in-human and induced blood-stage malaria phase 1a/b trial, we investigated the safety, tolerability, pharmacokinetics, and antimalarial activity of SJ733 in humans. METHODS: The phase 1a was a single-centre, dose-escalation, first-in-human study of SJ733 allowing modifications to dose increments and dose-cohort size on the basis of safety and pharmacokinetic results. The phase 1a took place at St Jude Children's Research Hospital and at the University of Tennessee Clinical Research Center (Memphis, TN, USA). Enrolment in more than one non-consecutive dose cohort was allowed with at least 14 days required between doses. Participants were fasted in seven dose cohorts and fed in one 600 mg dose cohort. Single ascending doses of SJ733 (75, 150, 300, 600, 900, or 1200 mg) were administered to participants, who were followed up for 14 days after SJ733 dosing. Phase 1a primary endpoints were safety, tolerability, and pharmacokinetics of SJ733, and identification of an SJ733 dose to test in the induced blood-stage malaria model. The phase 1b was a single-centre, open-label, volunteer infection study using the induced blood-stage malaria model in which fasted participants were intravenously infected with blood-stage P falciparum and subsequently treated with a single dose of SJ733. Phase 1b took place at Q-Pharm (Herston, QLD, Australia) and was initiated only after phase 1a showed that exposure exceeding the threshold minimum exposure could be safely achieved in humans. Participants were inoculated on day 0 with P falciparum-infected human erythrocytes (around 2800 parasites in the 150 mg dose cohort and around 2300 parasites in the 600 mg dose cohort), and parasitaemia was monitored before malaria inoculation, after inoculation, immediately before SJ733 dosing, and then post-dose. Participants were treated with SJ733 within 24 h of reaching 5000 parasites per mL or at a clinical score higher than 6. Phase 1b primary endpoints were calculation of a parasite reduction ratio (PRR48) and parasite clearance half-life, and safety and tolerability of SJ733 (incidence, severity, and drug-relatedness of adverse events). In both phases of the trial, SJ733 hydrochloride salt was formulated as a powder blend in capsules containing 75 mg or 300 mg for oral administration. Healthy men and women (of non-childbearing potential) aged 18-55 years were eligible for both studies. Both studies are registered with ClinicalTrials.gov (NCT02661373 for the phase 1a and NCT02867059 for the phase 1b). FINDINGS: In the phase 1a, 23 healthy participants were enrolled and received one to three non-consecutive doses of SJ733 between March 14 and Dec 7, 2016. SJ733 was safe and well tolerated at all doses and in fasted and fed conditions. 119 adverse events were recorded: 54 (45%) were unrelated, 63 (53%) unlikely to be related, and two (2%) possibly related to SJ733. In the phase 1b, 17 malaria-naive, healthy participants were enrolled. Seven participants in the 150 mg dose cohort were inoculated and dosed with SJ733. Eight participants in the 600 mg dose cohort were inoculated, but two participants could not be dosed with SJ733. Two additional participants were subsequently inoculated and dosed with SJ733. SJ733 exposure increased proportional to the dose through to the 600 mg dose, then was saturable at higher doses. Fasted participants receiving 600 mg exceeded the target area under the concentration curve extrapolated to infinity (AUC0-∞) of 13 000 µg × h/L (median AUC0-∞ 24 283 [IQR 16 135-31 311] µg × h/L, median terminal half-life 17·4 h [IQR 16·1-24·0], and median timepoint at which peak plasma concentration is reached 1·0 h [0·6-1·3]), and this dose was tested in the phase 1b. All 15 participants dosed with SJ733 had at least one adverse event. Of the 172 adverse events recorded, 128 (74%) were mild. The only adverse event attributed to SJ733 was mild bilateral foot paraesthesia that lasted 3·75 h and resolved spontaneously. The most common adverse events were related to malaria. Based on parasite clearance half-life, the derived log10PRR48 and corresponding parasite clearance half-lives were 2·2 (95% CI 2·0-2·5) and 6·47 h (95% CI 5·88-7·18) for 150 mg, and 4·1 (3·7-4·4) and 3·56 h (3·29-3·88) for 600 mg. INTERPRETATION: The favourable pharmacokinetic, tolerability, and safety profile of SJ733, and rapid antiparasitic effect support its development as a fast-acting component of combination antimalarial therapy. FUNDING: Global Health Innovative Technology Fund, Medicines for Malaria Venture, and the American Lebanese Syrian Associated Charities.

Baseline Serum Vitamin A and D Levels Determine Benefit of Oral Vitamin A&D Supplements to Humoral Immune Responses Following Pediatric Influenza Vaccination.

Maximizing vaccine efficacy is critical, but previous research has failed to provide a one-size-fits-all solution. Although vitamin A and vitamin D supplementation studies have been designed to improve vaccine efficacy, experimental results have been inconclusive. Information is urgently needed to explain study discrepancies and to provide guidance for the future use of vitamin supplements at the time of vaccination. We conducted a randomized, blinded, placebo-controlled study of influenza virus vaccination and vitamin supplementation among 2 to 8 (inclusive) year old children over three seasons, including 2015-2016 (n = 9), 2016-2017 (n = 44), and 2017-2018 (n = 26). Baseline measurements of vitamins A and D were obtained from all participants. Measurements were of serum retinol, retinol-binding protein (RBP, a surrogate for retinol), and 25-hydroxyvitamin D (25(OH)D). Participants were stratified into two groups based on high and low incoming levels of RBP. Children received two doses of the seasonal influenza virus vaccine on days 0 and 28, either with an oral vitamin supplement (termed A&D; 20,000 IU retinyl palmitate and 2000 IU cholecalciferol) or a matched placebo. Hemagglutination inhibition (HAI) antibody responses were evaluated toward all four components of the influenza virus vaccines on days 0, 28, and 56. Our primary data were from season 2016-2017, as enrollment was highest in this season and all children exhibited homogeneous and negative HAI responses toward the Phuket vaccine at study entry. Responses among children who entered the study with insufficient or deficient levels of RBP and 25(OH)D benefited from the A&D supplement (p < 0.001 for the day 28 Phuket response), whereas responses among children with replete levels of RBP and 25(OH)D at baseline were unaffected or weakened (p = 0.02 for the day 28 Phuket response). High baseline RBP levels associated with high HAI titers, particularly for children in the placebo group (baseline RBP correlated positively with Phuket HAI titers on day 28, r = 0.6, p = 0.003). In contrast, high baseline 25(OH)D levels associated with weak HAI titers, particularly for children in the A&D group (baseline 25(OH)D correlated negatively with Phuket HAI titers on day 28, r = -0.5, p = 0.02). Overall, our study demonstrates that vitamin A&D supplementation can improve immune responses to vaccines when children are vitamin A and D-insufficient at baseline. Results provide guidance for the appropriate use of vitamins A and D in future clinical vaccine studies.

Use of Placebo Pills Before Treatment Initiation in Youth with HIV: Are They Ready?

Highly active antiretroviral therapy (HAART) nonadherence is related to negative health outcomes and is well-documented in adolescents and young adults (AYAs) with behaviorally acquired HIV. Few studies describe methods to improve adherence in this population. This retrospective study describes placebo pill trial use (ie, pills with inert substance prescribed to practice taking HAART) in AYAs initiating HAART and its relation to disease outcomes. Sixty-two AYAs initiated HAART during the review period. Disease outcomes during the first year of standard clinical care were abstracted from medical records. In all, 72.6% of participants received ≥1 pill trial and 27.4% received ≥2 trials. Placebo trial use was not independently related to adherence post-HAART initiation. "Prescription" of a second trial was related to less optimal disease status over the first 6 months of treatment. Placebo trials have the potential to inform clinical care, aid in identifying AYAs at risk for nonadherence, and may provide a novel intervention strategy before/after HAART initiation.

Pediatric HIV disclosure: a process-oriented framework.

As children with vertically transmitted human immunodeficiency virus (HIV) infection live into adulthood, caregivers face the stressful process of informing their children about their infection. Although developmentally guided disclosure of HIV status is widely recommended, there are few specific frameworks to guide caregivers, families, and health care providers through the disclosure process. The authors propose a process-oriented framework for the disclosure of HIV in children and adolescents. This educational framework incorporates Piaget's cognitive development theory in an attempt to disclose and assist children and adolescents in understanding their HIV status. The framework is organized into 10 sequential stages of disclosure and three assessment stages in which health care providers discuss HIV health concepts with the child and caregiver, based on the child's developmental readiness. The described framework can be easily replicated by health care providers in disclosing disease status to children with HIV.