Pharmacokinetics and safety of coformulated bictegravir, emtricitabine, and tenofovir alafenamide in children aged 2 years and older with virologically suppressed HIV: a phase 2/3, open-label, single-arm study.

BACKGROUND: Coformulated bictegravir, emtricitabine, and tenofovir alafenamide is a single-tablet regimen and was efficacious and well tolerated in children and adolescents with HIV (aged 6 years to <18 years) in a 48-week phase 2/3 trial. In this study, we report data from children aged at least 2 years and weighing 14 kg to less than 25 kg. METHODS: We conducted this open-label, multicentre, multicohort, single-arm study in South Africa, Thailand, Uganda, and the USA. Participants were virologically suppressed children with HIV, aged at least 2 years, weighing 14 kg to less than 25 kg. Participants received bictegravir (30 mg), emtricitabine (120 mg), and tenofovir alafenamide (15 mg) once daily, switching to bictegravir (50 mg), emtricitabine (200 mg), and tenofovir alafenamide (25 mg) upon attaining a bodyweight of at least 25 kg. The study included pharmacokinetic evaluation at week 2 to confirm the dose of coformulated bictegravir, emtricitabine, and tenofovir alafenamide for this weight band by comparing with previous adult data. Primary outcomes were bictegravir area under the curve over the dosing interval (AUCtau) and concentration at the end of the dosing interval (Ctau) at week 2, and incidence of treatment-emergent adverse events and laboratory abnormalities until the end of week 24 in all participants who received at least one dose of bictegravir, emtricitabine, and tenofovir alafenamide. This study is registered with ClinicalTrials.gov, NCT02881320. FINDINGS: Overall, 22 participants were screened (from Nov 14, 2018, to Jan 11, 2020), completed treatment with bictegravir, emtricitabine, and tenofovir alafenamide (until week 48), and entered an extension phase. The geometric least squares mean (GLSM) ratio for AUCtau for bictegravir was 7·6% higher than adults (GLSM ratio 107·6%, 90% CI 96·7-119·7); Ctau was 34·6% lower than adults (65·4%, 49·1-87·2). Both parameters were within the target exposure range previously found in adults, children, or both". Grade 3-4 laboratory abnormalities occurred in four (18%) participants by the end week 24 and six (27%) by the end of week 48. Drug-related adverse events occurred in three participants (14%) by the end of week 24 and week 48; none were severe. No Grade 3-4 adverse events, serious adverse events, or adverse events leading to discontinuation occurred by the end of week 24 and week 48. INTERPRETATION: Data support the use of single-tablet coformulated bictegravir (30 mg), emtricitabine (120 mg), and tenofovir alafenamide (15 mg) for treatment of HIV in children aged at least 2 years and weighing 14 kg to less than 25 kg. FUNDING: Gilead Sciences.

High mortality in adolescents and young adults with perinatally-acquired HIV in Thailand during the transition to adulthood.

Transitioning from pediatric to adult care remains a challenge for adolescents and young adults with perinatally-acquired HIV (AYA-PHIV). We assessed treatment outcomes and mortality among Thai AYA-PHIV. The study included AYA-PHIV who reached age 18-24 years who started antiretroviral treatment during childhood at five pediatric HIV clinics across Thailand. From November 2020-July 2021, data were gathered from a cohort database, medical records, and the Thai National AIDS Program. Of 811 eligible AYA-PHIV, 93% were alive; median age 22.3 years (IQR 20.6-23.7), treatment duration 16.1 years (IQR 13.4-18.0). Current HIV care was provided in adults (71%) and pediatric clinics (29%). Treatment regimens included non-nucleoside reverse transcriptase inhibitors (55%), protease inhibitors (36%), and integrase inhibitors (8%); 78% had HIV RNA <200 copies/ml. Of the 7.0% who died, median age at death was 20.8 years (IQR 20.6-22.1); 88% were AIDS-related death. Mortality after age 18 was 1.76 per 100-person years (95% confidence interval 1.36-2.28). Those with CD4 <200 cell/mm3 at age 15 had higher risk of mortality (adjusted hazard ratio 6.16, 95% CI 2.37-16.02). In conclusion, the high mortality among Thai AYA-PHIV indicated the need for better systems to support AYA-PHIV during the transition to adulthood.

Antibodies against SARS-CoV-2 in unvaccinated children hospitalized with COVID-19: An observational cohort study of pre-Omicron and Omicron variants era.

PURPOSE: This study aimed to investigate the antibodies against SARS-CoV-2 in children hospitalized due to COVID-19 during the era of pre-Omicron and Omicron variants. METHODS: This was a retrospective observational study conducted at a tertiary academic medical center in Thailand between June 2021 and August 2022. We collected the data of children aged under 18-year who were hospitalized from SARS-CoV-2 infection. After hospital discharge, we scheduled clinical follow-up 60 to 90 days post-infection clinical follow-up. We measured antibodies against SARS-CoV-2 anti-spike protein receptor-binding domain in the serum during a follow-up visit and compared the mean difference of antibody levels between children infected with COVID-19 during the pre-Omicron and Omicron eras. RESULTS: A total of 119 children enrolled into the study. There were 58 and 61 children hospitalized due to COVID-19 during pre-Omicron and Omicron era, respectively. The median (interquartile range, IQR) of SARS-CoV-2 antibodies in all cases was 206.1 (87.9-424.1) U/mL at follow-up. Children infected during pre-Omicron had SARS-CoV-2 antibody levels at follow-up higher than children infected during Omicron era [mean difference 292.57 U/mL, 95% CI 53.85-531.28, p = 0.017). There was no difference in SARS-CoV-2 antibody levels between the children based on gender, age, co-morbidities, chest radiograph classification, or diagnosis. CONCLUSIONS: The antibodies response to SARS-CoV-2 infection was weaker during the Omicron era than previous variant of concern. Immunization strategies and policies should be implemented in children even if they had been previously infected.

Long-term efficacy and safety of a tetravalent dengue vaccine (TAK-003): 4·5-year results from a phase 3, randomised, double-blind, placebo-controlled trial.

BACKGROUND: About half of the world's population lives in dengue-endemic areas. We aimed to evaluate the long-term efficacy and safety of two doses of the tetravalent dengue vaccine TAK-003 in preventing symptomatic dengue disease of any severity and due to any dengue virus (DENV) serotypes in children and adolescents. METHODS: In this ongoing double-blind, randomised, placebo-controlled trial, we enrolled healthy participants aged 4-16 years at 26 medical and research centres across eight dengue-endemic countries (Brazil, Colombia, Dominican Republic, Nicaragua, Panama, Philippines, Sri Lanka, and Thailand). The main exclusion criteria were febrile illness (body temperature ≥38°C) at the time of randomisation, hypersensitivity or allergy to any of the vaccine components, pregnancy or breastfeeding, serious chronic or progressive disease, impaired or altered immune function, and previous receipt of a dengue vaccine. Participants were randomly assigned 2:1 (stratified by age and region) using an interactive web response system and dynamic block assignment to receive two subcutaneous doses of TAK-003 or placebo 3 months apart. Investigators, participants, and their parents or legal guardians were blinded to group assignments. Active febrile illness surveillance and RT-PCR testing of febrile illness episodes were performed for identification of virologically confirmed dengue. Efficacy outcomes were assessed in the safety analysis set (all randomly assigned participants who received ≥1 dose) and the per protocol set (all participants who had no major protocol violations), and included cumulative vaccine efficacy from first vaccination to approximately 4·5 years after the second vaccination. Serious adverse events were monitored throughout. This study is registered with ClinicalTrials.gov, NCT02747927. FINDINGS: Between Sept 7, 2016, and March 31, 2017, 20 099 participants were randomly assigned (TAK-003, n=13 401; placebo, n=6698). 20 071 participants (10 142 [50·5%] males; 9929 [49·5%] females; safety set) received TAK-003 or placebo, with 18 257 (91·0%) completing approximately 4·5 years of follow-up after the second vaccination (TAK-003, 12 177/13 380; placebo, 6080/6687). Overall, 1007 (placebo: 560; TAK-003: 447) of 27 684 febrile illnesses reported were virologically confirmed dengue, with 188 cases (placebo: 142; TAK-003: 46) requiring hospitalisation. Cumulative vaccine efficacy was 61·2% (95% CI 56·0-65·8) against virologically confirmed dengue and 84·1% (77·8-88·6) against hospitalised virologically confirmed dengue; corresponding efficacies were 53·5% (41·6-62·9) and 79·3% (63·5-88·2) in baseline seronegative participants (safety set). In an exploratory analysis, vaccine efficacy was shown against all four serotypes in baseline seropositive participants. In baseline seronegative participants, vaccine efficacy was shown against DENV-1 and DENV-2 but was not observed against DENV-3 and low incidence precluded evaluation against DENV-4. During part 3 of the trial (approximately 22-57 months after the first vaccination), serious adverse events were reported for 664 (5·0%) of 13 380 TAK-003 recipients and 396 (5·9%) of 6687 placebo recipients; 17 deaths (6 in the placebo group and 11 in the TAK-003 group) were reported, none were considered study-vaccine related. INTERPRETATION: TAK-003 demonstrated long-term efficacy and safety against all four DENV serotypes in previously exposed individuals and against DENV-1 and DENV-2 in dengue-naive individuals. FUNDING: Takeda Vaccines. TRANSLATIONS: For the Portuguese, Spanish translations and plain language summary of the abstract see Supplementary Materials section.

Case Report: Melioidosis-Related Severe Cutaneous Features of Erythema Nodosum in a Thai Child.

Erythema nodosum (EN) is characterized by rapidly developing, painful, erythematous subcutaneous nodules, most of which are located in the pretibial areas. This cutaneous finding can be caused by a variety of conditions, however Burkholderia pseudomallei is rarely the cause. This particular patient presented with a high-grade fever with characteristic EN on both pretibial areas. All of the typical EN causes were investigated, but the findings were all negative. The lesions progressed to severe hemorrhagic bleb features, and because the patient resided in Northeast Thailand, a melioidosis-endemic region, testing for B. pseudomallei was performed. Because a high level of melioidosis serology of more than 1:10,240 was detected, melioidosis therapy was started. At the 12-week follow-up after melioidosis therapy, the titer had declined to 1:1,280, indicating that melioidosis-related severe, cutaneous EN symptoms were the most likely diagnosis in this patient. We discovered a case of EN with severe hemorrhagic bleb features as a unique clinical manifestation of melioidosis. When a patient resides in an endemic area, B. pseudomallei should always be considered as a possible causative organism.

Hybrid immunity from SARS-CoV-2 infection and mRNA BNT162b2 vaccine among Thai school-aged children.

Objective: To compare the immune response of hybrid immunity - arising from SARS-CoV-2 infection and mRNA BNT162b2 vaccination - to that of 2-doses of vaccine. Methods: In a subanalysis of BNT162b2 vaccine trial in 5 to 11-year-old children, There were 179 children who had hybrid immunity compared with 134 children with solely 2-dose vaccine. The immunological outcome was a surrogate virus neutralization test (sVNT) against the Omicron strain, BA.1, (%inhibition). An sVNT level ≥68 % inhibition was considered as protective immune response. Results: From February to April 2022, 179 children had COVID-19 natural infection resulting in hybrid immunity included: Group1;prior vaccination(n = 17), Group2;after the first dose(n = 61), and Group3;after the second dose(n = 97). The proportion of children with protective immune response was higher in Group 3 and Group 1 - 61.9 % and 58.8 %, compared to 36.1 % and 34.3 % in Group 2 and comparator group (2 doses of vaccine), respectively. The geometric mean % inhibition of sVNT was higher in Group 1 (68.5, 95 %CI 55.5-84.6) and Group 3 (63.5, 95 %CI 55.5-72.6), followed by comparator group (49.6, 95 %CI 44.8-54.9) and Group 2 (42.1, 95 %CI 34.6-51.3), p < 0.001. Conclusions: Immune response that arises from BNT162b2 vaccine after natural infection and infection after 2 doses of BNT162b2 was higher than infection after partially-vaccinated children.

ACORN (A Clinically-Oriented Antimicrobial Resistance Surveillance Network) II: protocol for case based antimicrobial resistance surveillance.

Background: Antimicrobial resistance surveillance is essential for empiric antibiotic prescribing, infection prevention and control policies and to drive novel antibiotic discovery. However, most existing surveillance systems are isolate-based without supporting patient-based clinical data, and not widely implemented especially in low- and middle-income countries (LMICs). Methods: A Clinically-Oriented Antimicrobial Resistance Surveillance Network (ACORN) II is a large-scale multicentre protocol which builds on the WHO Global Antimicrobial Resistance and Use Surveillance System to estimate syndromic and pathogen outcomes along with associated health economic costs. ACORN-healthcare associated infection (ACORN-HAI) is an extension study which focuses on healthcare-associated bloodstream infections and ventilator-associated pneumonia. Our main aim is to implement an efficient clinically-oriented antimicrobial resistance surveillance system, which can be incorporated as part of routine workflow in hospitals in LMICs. These surveillance systems include hospitalised patients of any age with clinically compatible acute community-acquired or healthcare-associated bacterial infection syndromes, and who were prescribed parenteral antibiotics. Diagnostic stewardship activities will be implemented to optimise microbiology culture specimen collection practices. Basic patient characteristics, clinician diagnosis, empiric treatment, infection severity and risk factors for HAI are recorded on enrolment and during 28-day follow-up. An R Shiny application can be used offline and online for merging clinical and microbiology data, and generating collated reports to inform local antibiotic stewardship and infection control policies. Discussion: ACORN II is a comprehensive antimicrobial resistance surveillance activity which advocates pragmatic implementation and prioritises improving local diagnostic and antibiotic prescribing practices through patient-centred data collection. These data can be rapidly communicated to local physicians and infection prevention and control teams. Relative ease of data collection promotes sustainability and maximises participation and scalability. With ACORN-HAI as an example, ACORN II has the capacity to accommodate extensions to investigate further specific questions of interest.

The changing characteristics of a cohort of children and adolescents living with HIV at antiretroviral therapy initiation in Asia.

Despite improvements in HIV testing and earlier antiretroviral therapy (ART) initiation in children living with HIV through the years, a considerable proportion start treatment with advanced disease. We studied characteristics of children and adolescents living with HIV and their level of immunodeficiency at ART initiation using data from a multi-country Asian cohort. We included children and adolescents who were ART-naïve and <18 years of age at ART initiation from 2011 to 2020 at 17 HIV clinics in six countries. Incidence rates of opportunistic infections (OIs) in the first two years of triple-drug ART (≥3 antiretrovirals) was also reported. Competing risk regression analysis was performed to identify factors associated with first occurrence of OI. In 2,027 children and adolescents (54% males), median age at ART initiation increased from 4.5 years in 2011-2013 to 6.7 in 2017-2020, median CD4 count doubled from 237 cells/µl to 466 cells/µl, and proportion of children who initiated ART as severely immunodeficient decreased from 70% to 45%. During follow-up, 275 (14%) children who received triple-drug ART as first treatment and had at least one clinic visit, developed at least one OI in the first two years of treatment (9.40 per 100 person-years). The incidence rate of any first OI declined from 12.52 to 7.58 per 100 person-years during 2011-2013 and 2017-2020. Lower hazard of OIs were found in those with age at first ART 2-14 years, current CD4 ≥200 cells/µl, and receiving ART between 2017 and 2020. The analysis demonstrated increasing number of children and adolescents starting ART with high CD4 count at ART start. The rate of first OI markedly decreased in children who started ART in more recent years. There remains a clear need for improvement in HIV control strategies in children, by promoting earlier diagnosis and timely treatment.

Immunogenicity and reactogenicity of fractional, heterologous primary COVID-19 vaccination schedules with BNT162b2 boosters in 5-11-year-old Thai children: A multicenter, prospective, double-blind, randomized control trial.

OBJECTIVE: To evaluate immunogenicity and safety of heterologous COVID-19 primary vaccination regimens of CoronaVac with fractional and standard BNT162b2 dosages in 5-11-year-old Thai children. METHODS: This prospective, multicenter, double-blind, randomized control trial divided participants 1:1:1:1 to receive a second dose of either standard (10-µg) or half-dose (5-µg) BNT162b2 vaccines as follows: CoronaVac/10-µg-BNT162b2 (Group 1), CoronaVac/5-µg-BNT162b2 (Group 2), 10-µg-BNT162b2/10-µg-BNT162b2 (Group 3), or 10-µg-BNT162b2/5-µg-BNT162b2 (Group 4). A subset of participants from each arm received 10-µg-BNT162b2 booster (third) doses 16 weeks after their second vaccination. Humoral and cellular immunogenicity were assessed and adverse events (AEs) digitally self-reported. RESULTS: Of 553 enrolled participants, 50 % were male, the median (interquartile range) age was 8.65 (7.00, 10.00) years, and a majority (91 %) had normal weight-for-height. All participants exhibited similarly robust neutralizing antibodies (NAb) against the ancestral Wuhan strain two weeks after the second vaccination, with titers highest in Group 1 (737.60, 95% CI [654.80, 830.88]), followed by Groups 3 (630.42, 95% CI [555.50, 715.45]), 2 (593.98, 95% CI [506.02, 697.23]), and 4 (451.79, 95% CI [388.62, 525.23]), as well as 56.01 % and 49.68 % seroconversion for BA.1 and BA.5, respectively. Half-dose BNT162b2 as a second dose induced significantly lower NAb titers compared to their respective full-dose regimens (p = 0.03 for Groups 1 vs 2 and p < 0.001 for Groups 3 vs 4). 77.71 % of participants developed SARS-CoV-2 ancestral spike protein-specific T-cell responses two weeks after the second vaccination. This was similar across arms. Booster doses generated NAb titers 5.69-11.51-folds higher than the second vaccination against BA.1. AEs were similar across arms, all mild or moderate, and fully resolved 2-3 days thereafter. CONCLUSION: Standard and fractional heterologous regimens of CoronaVac-BNT162b2 induced similar or higher humoral immunity than homologous BNT162b2 and represent alternative vaccine regimens for children. These findings are highly relevant in settings concurrently using both vaccines.

Outcomes among Thai children with risk conditions hospitalized for pneumococcal disease (invasive or non-bacteraemic pneumonia): A multi-centre, observational study.

Objective: To describe the risk condition status and clinical outcomes among Thai children hospitalized with pneumococcal disease. Methods: In this retrospective analysis, children with invasive pneumococcal disease (IPD) or x-ray-confirmed non-bacteraemic pneumococcal pneumonia (NBPP) were identified from nine hospitals in Thailand between 2010 and 2019. Data on risk factors and outcomes were extracted from medical records. Results: In total, 413 cases were identified: 319 IPD and 94 NBPP. Overall, 133 (32.2%) patients were admitted to intensive care units and 11/406 (2.7%) died. Twenty-seven percent of IPD cases had at-risk conditions and 15% had high-risk conditions. Most IPD cases (32.9%) occurred in children aged 2-4 years, and most NBPP cases (28.7%) occurred in infants aged 0-11 months. Of 51 Streptococcus pneumoniae isolates collected, 41 (80%) were pneumococcal 13-valent conjugate vaccine serotypes. Only 5.1% of children had received a pneumococcal vaccine. Conclusions: Most children with IPD and NBPP did not have high-risk or at-risk conditions, while 42% had at-risk or high-risk conditions for pneumococcal disease. Very few children in the cohort had received any type of pneumococcal vaccine. Increasing the availability of pneumococcal conjugate vaccines should be considered to reduce the burden of pneumococcal disease among children in Thailand.

Immunogenicity and Safety of a Hexavalent DTwP-IPV-HB-PRP~T Vaccine Versus Separate DTwP-HB-PRP~T, bOPV, and IPV Vaccines Administered at 2, 4, 6 Months of Age Concomitantly With Rotavirus and Pneumococcal Conjugate Vaccines in Healthy Infants in Thailand.

BACKGROUND: This study investigated the immunogenicity and safety of a fully liquid, hexavalent, diphtheria (D)-tetanus (T)-whole-cell pertussis (wP)-inactivated poliovirus (IPV)-hepatitis B (HB)- Haemophilus influenzae b (PRP-T) vaccine compared to licensed DTwP-HB-PRP~T, IPV, and bivalent oral poliovirus (bOPV) vaccines following co-administration with other pediatric vaccines [pneumococcal conjugate vaccine (PCV13) and rotavirus vaccine]. METHODS: Phase III, randomized, open-label study in Thailand. Healthy infants received DTwP-IPV-HB-PRP~T at 2, 4 and 6 months of age (N = 228), or DTwP-HB-PRP~T and bOPV (2, 4 and 6 months of age) and IPV (4 months of age) (N = 231). All participants received PCV13 (2, 4 and 6 months of age) and rotavirus vaccine (2 and 4 months of age). Immunogenicity for all antigens was assessed using validated assays, and noninferiority post-third dose was evaluated for anti-D, anti-T, anti-pertussis [anti-pertussis toxin (anti-PT) and anti-fimbriae 2/3 (anti-FIM)], anti-polio 1, 2, 3, anti-HB, and anti-PRP~T. Safety was assessed using parental reports. RESULTS: Noninferiority was demonstrated for each antigen, and overall noninferiority of DTwP-IPV-HB-PRP~T versus DTwP-HB-PRP~T+bOPV+IPV was concluded. Similarity in each group was observed for the GMC ratio for antirotavirus antibodies (20.9 and 17.3, respectively) and anti-PCV13 antibodies (range: 8.46-32.6 and 7.53-33.1, respectively). Two serious adverse events were related to DTwP-IPV-HB-PRP~T (febrile convulsion and acute febrile illness) and 1 was related to DTwP-HB-PRP~T+bOPV+IPV (febrile seizure), but overall there were no safety concerns with similar rates of participants experiencing solicited (99.1% and 98.3%) and unsolicited (19.3% and 19.5%) adverse events in each group. CONCLUSIONS: This study confirmed the suitability of DTwP-IPV-HB-PRP~T primary series vaccination in combination with rotavirus and PCV13 vaccines.

A phase 3 study of safety and immunogenicity of V114, a 15-valent pneumococcal conjugate vaccine, followed by 23-valent pneumococcal polysaccharide vaccine, in children with HIV.

OBJECTIVES: To evaluate the safety and immunogenicity of V114 [15-valent pneumococcal conjugate vaccine (PCV) containing serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9 V, 14, 18C, 19A, 19F, 22F, 23F, 33F], followed by 23-valent pneumococcal polysaccharide vaccine (PPSV23) 8 weeks later, in children with HIV. DESIGN: This phase 3 study (NCT03921424) randomized participants 6-17 years of age with HIV (CD4 + T-cell count ≥200 cells/µl, plasma HIV RNA <50 000 copies/ml) to receive V114 or 13-valent PCV (PCV13) in a double-blind manner on Day 1, followed by PPSV23 at Week 8. METHODS: Adverse events (AEs), pneumococcal serotype-specific immunoglobulin G (IgG), and opsonophagocytic activity (OPA) were evaluated 30 days after each vaccination. RESULTS: The proportion of participants experiencing at least one AE post-PCV was 78.8% in the V114 group ( n  = 203) and 69.6% in the PCV13 group ( n  = 204); respective proportions post-PPSV23 were 75.4% ( n  = 203) and 77.2% ( n  = 202). There were no vaccine-related serious AEs. IgG geometric mean concentrations (GMCs) and OPA geometric mean titers (GMTs) were generally comparable between V114 and PCV13 for shared serotypes at Day 30, and were higher for V114 compared with PCV13 for the additional V114 serotypes 22F and 33F. Approximately 30 days after PPSV23, IgG GMCs and OPA GMTs were generally comparable between the V114 and PCV13 groups for all 15 serotypes in V114. CONCLUSIONS: In children with HIV, a sequential administration of V114 followed 8 weeks later with PPSV23 is well tolerated and induces immune responses for all 15 pneumococcal serotypes included in V114.

Alcohol use, suicidality and virologic non-suppression among young adults with perinatally acquired HIV in Thailand: a cross-sectional study.

INTRODUCTION: Young adults with perinatally acquired HIV (YA-PHIV) are facing transitions to adult life. This study assessed health risk behaviours (including substance use), mental health, quality of life (QOL) and HIV treatment outcomes of Thai YA-PHIV. METHODS: A cross-sectional study was conducted in Thai YA-PHIV aged 18-25 years who were enrolled in a prospective cohort study at five tertiary paediatric HIV care centres in Thailand. Study data were obtained through face-to-face interviews from November 2020 to July 2021. Assessments were performed for alcohol use (Alcohol Use Disorders Identification Test; AUDIT), smoking (Fagerstrom Test for Nicotine Dependence), drug/substance use (Drug Abuse Screening Test; DAST-10), depression (Patient Health Questionnaire for Adolescents; PHQ-A), anxiety (Generalized Anxiety Disorder; GAD-7) and QOL (World Health Organization QOL Brief-Thai). HIV treatment outcomes were extracted from the National AIDS Program database. RESULTS: Of 355 YA-PHIV, 163 (46%) were males: their median age was 21.7 (interquartile range, IQR 20.2-23.5) years. There were 203 YA-PHIV (58%) who reported ever having sex; 141 (40%) were sexually active in the past 6 months, of whom 86 (61%) reported 100% condom use. Overall, 49 (14%) met the criteria for harmful alcohol use; 28 (7.9%) were alcohol dependent. Sixty (17%) were current smokers and 37 (11%) used drugs/substances. The frequency of moderate up to severe symptoms for depression was 18% and for anxiety was 9.7%. Their overall QOL was good in 180 (51%), moderate in 168 (47%) and poor in five (1.4%). There were 49 YA-PHIV (14%) with CD4 <200 cells/mm3 and 85 (24%) with virologic non-suppression (HIV-RNA >200 copies/ml). On multivariate analyses, the highest education at the primary to high school or vocational school levels (adjusted odds ratio [aOR] 2.02, 95% CI 1.40-3.95, p 0.04), harmful alcohol use (aOR 2.48, 95% CI 1.24-4.99, p 0.01), alcohol dependence (aOR 3.54, 95% CI 1.51-8.31, p <0.01) and lifetime suicidal attempt (aOR 2.66, 95% CI 1.11-6.35, p 0.03) were associated with non-suppression. CONCLUSIONS: Regular screening for alcohol use and mental health, including suicidality, would be useful to identify YA-PHIV who need more intensive psychosocial support or referral services to ensure they can achieve and maintain a high QOL into adult life.

The immunogenicity of an extended dosing interval of BNT162b2 against SARS-CoV-2 Omicron variant among healthy school-aged children, a randomized controlled trial.

OBJECTIVES: To evaluate the immunogenicity of an extended interval regimen of BNT162b2 among healthy school-age children. METHODS: A randomized-control trial conducted among healthy Thai children aged 5-11 years. Participants received two doses of BNT162b2 with an 8-week (extended dosing) vs 3-week interval. Immunogenicity was determined by neutralization test (NT) against the Omicron variant, surrogate virus NT (sVNT; BA.1, % inhibition), and pseudovirus NT (BA.2, the half-maximal inhibition dilution or ID50). The third dose was offered to participants who had sVNT <68% inhibition. The immunogenicity outcome was evaluated at 14 days after the second and third doses. RESULTS: During February to April 2022, 382 children with a median age (interquartile range) of 8.4 years (6.6-10.0) were enrolled. At 14 days, after two doses of BNT162b2, the geometric means of sVNT in 8-week vs 3-week interval groups were 49.6 (95% confidence interval [CI] 44.8-54.9) vs 16.5 (95% CI 13.0-20.9), with a geometric means ratio of 3.0 (95% CI 2.4-3.8). Among 102 participants who received the third dose at a median of 15 weeks from the second dose, the geometric means of sVNT increased to 73.3 (95% CI 69.0-77.8) and pseudovirus NT increased to 326 (95% CI 256-415). CONCLUSION: The extended 8-week interval regimen of BNT162b2 induced higher neutralizing antibodies than a standard 3-week interval regimen. The third dose induced high neutralizing antibodies against the Omicron variant.

Pregnancy and birth outcomes among young women living with perinatally acquired HIV in Thailand and Vietnam.

We conducted a retrospective cohort study of pregnancy and infant outcomes in 670 adolescents and young adult women with perinatally acquired HIV (AYAPHIV), aged 15-24 years, in Thailand and Vietnam. Between January 2013 and December 2018, there were 52 pregnancies, for an incidence of 2.49 (95% CI 1.90-3.27) per 100 person-years. The median age at pregnancy was 17.7 years (IQR 16.8-18.9). Pregnant AYAPHIV had been on cART for a lifetime median of 9.8 years (IQR 7.3-12.4). At the time of conception, the median CD4 was 521 cells/mm3 (IQR 213-760), and 76% had HIV RNA ≤400 copies/ml. Of the 51 pregnancies with available outcomes, 90% resulted in live singleton births at a median gestational age of 38 weeks (IQR 37-39); 77% of mothers (n = 27/35) had HIV RNA ≤400 copies/ml at delivery. Among infants with available data, 50% (n = 21/42) were male and 29% (n = 12/42) were reported to be low birthweight (<2,500gm); none (n = 0/41) were breastfed. One infant was diagnosed with HIV. Our findings emphasize that efforts to strengthen reproductive health education, including contraception, pregnancy-related psychosocial support services, and prevention of vertical HIV transmission interventions, in our region are needed for adolescents with perinatally acquired HIV as they transition to young adults.

A phase 3, multicenter, randomized, double-blind study to evaluate the interchangeability of V114, a 15-valent pneumococcal conjugate vaccine, and PCV13 with respect to safety, tolerability, and immunogenicity in healthy infants (PNEU-DIRECTION).

BACKGROUND: Pneumococcal disease (PD) remains a major health concern globally. In children, pneumococcal conjugate vaccines (PCVs) provide protection against PD from most vaccine serotypes, but non-vaccine serotypes contribute to residual disease. V114 is a 15-valent PCV containing all 13 serotypes in Prevnar 13™ (PCV13) and public health important serotypes 22F and 33F. This phase 3 study evaluated safety and immunogenicity of mixed PCV13/V114 regimens using a 3 + 1 dosing schedule when changing from PCV13 to V114 at doses 2, 3, or 4. METHODS: 900 healthy infants were randomized equally to 5 intervention groups. PCVs were administered in a 3-dose infant series at 2, 4, and 6 months of age followed by a toddler dose at 12-15 months along with concomitant routine vaccines. Safety was evaluated as the proportion of participants with adverse events (AEs). Immunoglobulin G (IgG) responses to the 15 serotypes in V114 were measured at 30 days post-dose 3 and 30 days post-dose 4 (PD4). RESULTS: Frequencies of injection-site and systemic AEs were generally comparable across all intervention groups. At 30 days PD4 (primary endpoint), IgG geometric mean concentrations (GMCs) for the 13 shared serotypes were generally comparable between mixed V114/PCV13 and 4-dose regimens of PCV13 or V114. In mixed regimens at 30 days PD4, a toddler dose of V114 was sufficient to achieve IgG GMCs comparable to a 4-dose regimen of V114 for serotype 22F, while at least one infant dose was needed in addition to the toddler dose to achieve IgG GMCs comparable to a 4-dose regimen of V114 for serotype 33F. CONCLUSIONS: V114 was well tolerated with a generally comparable safety profile to PCV13. For 13 shared serotypes, both mixed regimens and the V114 4-dose regimen induced generally comparable antibody responses to 4-dose regimen with PCV13. Study results support interchangeability of V114 with PCV13 in infants. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03620162; EudraCT: 2018-001151-12.

Immunogenicity of a Fractional Dose of mRNA BNT162b2 COVID-19 Vaccine for Primary Series and Booster Vaccination among Healthy Adolescents.

Primary series vaccination with BNT162b2 followed by a booster 5 months later has been recommended for healthy adolescents. We aimed to describe the immunogenicity in a fractional dose of BNT162b2. Adolescents aged 12-18 years were randomized into six arms for primary series administration: 3wPZ30/30 (reference group), 3wPZ30/20, 3wPZ20/20, 6wPZ30/30, 6wPZ30/20, and 6wPZ20/20 µg. A booster was given at 5 months after the second dose using either 10 or 15 µg of BNT162b2. Immunogenicity following vaccination was determined by IgG against receptor-binding domain (anti-S-RBD IgG; BAU/mL), surrogate virus neutralization test (sVNT; %inhibition) and pseudovirus neutralization (pVNT;ID50) against Omicron. Non-inferiority criteria were defined as a lower boundary of the geometric mean ratio (GMR) being greater than 0.67. From September to October 2021, 118 adolescents with a median age (IQR) of 14.9 years (13.9-16.7) were enrolled. Fourteen days after the primary series, the geometric means (GMs) of anti-S-RBD IgG (BAU/mL) were 3090 (95% CI 2761-3460) in 3wPZ30/30. The GMRs of anti-S-RBD were: 0.80 (95% CI 0.67-0.97) in 3wPZ30/20; 1.00 (95% CI 0.83-1.20) in 3wPZ20/20; 1.37 (95% CI 1.13-1.65) in 6wPZ30/30; 1.24 (95% CI 1.02-1.50) in 6wPZ30/20; and 1.36 (1.13-1.64) in 6wPZ20/20. After a booster dose with 15 µg (n = 24) of BNT162b2, sVNT and pVNT against Omicron variant were 91.6 (95% CI 88.4-94.9) and 331 (95% CI 221-495), respectively. In the group that received 10 µg of BNT162b2 (n = 25), sVNT was 85.6 (95% CI 80.0-91.6) and pVNT was 397 (95% CI 267-590). Healthy adolescents had good immune responses to the fractional dose regimen of BNT162b2 and this may be considered as an alternative option.

Outcomes of etravirine-based antiretroviral treatment in treatment-experienced children and adolescents living with HIV in Europe and Thailand.

BACKGROUND: Etravirine (ETR) is approved as a component of second or third-line antiretroviral treatment (ART) for children living with HIV. We assessed the outcomes of ETR-based ART in children in routine care in Europe and Thailand. METHODS: Data on children aged <18 years at ETR start were pooled from 17 observational cohorts. Characteristics at ETR start, immunological and virological outcomes at 12 months, discontinuations, adverse events (AEs) and serious adverse events (SAEs) were described. Follow-up was censored at ETR discontinuation, death or last visit. RESULTS: 177 children ever received ETR. At ETR start, median [IQR] age was 15 [12,16] years, CD4 count 480 [287, 713] cells/mm3, 70% had exposure to ≥3 ART classes and 20% had viral load (VL) <50 copies/mL. 95% received ETR in combination with ≥1 potent drug class, mostly protease inhibitor-based regimens. Median time on ETR was 24 [7, 48] months. Amongst those on ETR at 12 months (n=141), 69% had VL<50 copies/mL. Median CD4 increase since ETR start (n=83) was 147 [16, 267] cells/mm3. Overall, 81 (46%) discontinued ETR by last follow-up. Median time to discontinuation was 23 [8, 47] months. Common reasons for discontinuation were treatment simplification (19%), treatment failure (16%) and toxicity (12%). Eight children (5%) had AEs causally associated with ETR, all dermatological/hypersensitivity reactions. Two were SAEs, both Stevens-Johnson Syndrome in children on regimens containing ETR and darunavir and were causally related to either drugs; both resolved following ART discontinuation. CONCLUSION: Children receiving ETR were predominantly highly treatment-experienced, over two-thirds were virally suppressed at 12 months.

Switching efavirenz to rilpivirine in virologically suppressed adolescents with HIV: a multi-centre 48-week efficacy and safety study in Thailand.

INTRODUCTION: Efavirenz (EFV) is commonly used for first-line antiretroviral therapy in children and adolescents with HIV, but is associated with neuropsychiatric and metabolic side effects. Rilpivirine (RPV) is better tolerated, and switching from EFV to RPV in virologically suppressed adults has been safe and efficacious, but data in adolescents are limited. Our primary objective was to describe the 48-week immunologic and virologic outcomes in virologically suppressed adolescents switching from EFV- to RPV-based antiretroviral therapy. Secondary objectives included assessment of neuropsychiatric adverse events, quality of life (QOL) and metabolic profiles while on RPV. METHODS: We conducted an open-label, single-arm, multi-centre study in Thailand in virologically suppressed adolescents aged 12-18 years receiving EFV plus two nucleoside/tide reverse transcriptase inhibitors (NRTIs/NtRTI) for ≥3 months. Participants were switched to an RPV (25 mg) tablet once daily, with the same NRTIs. HIV RNA viral load, CD4 cell count, fasting total cholesterol (TC), triglyceride, glucose, neuropsychiatric adverse events, depression and QOL were assessed over 48 weeks. Data were collected between February 2016 and September 2018. RESULTS: One hundred and two (52% male) adolescents were enrolled. Median age at entry was 15.5 years (IQR 14.4-17.0), median CD4 count was 664 cells/mm3 (29.9%); 58% were receiving tenofovir-DF and emtricitabine. At weeks 24 and 48, 96 (94.1%) and 94 (92.2%) participants were virologically suppressed, respectively, with no significant change in CD4 cell counts from baseline. Six (5.9%) participants experienced virologic failure, two of whom had RPV-associated mutations (K101E and Y181C) and a lamivudine-associated mutation (M184V/I). There were significant decreases in TC, triglyceride, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) at weeks 24 and 48 and a significant increase in LDL/HDL ratio at week 48 compared to baseline. No substantial changes in EFV-related symptoms, depression score or health-related QOL were observed over time; however, there was significant improvement in performance-based assessments of executive function at week 24. CONCLUSIONS: A high proportion of adolescents (>92%) remained virologically suppressed up to 48 weeks after switching from EFV to RPV along with no significant change in CD4 cell counts. RPV was well tolerated and associated with improvements in metabolic profiles and executive function.

Three-year Efficacy and Safety of Takeda's Dengue Vaccine Candidate (TAK-003).

BACKGROUND: Takeda's live attenuated tetravalent dengue vaccine candidate (TAK-003) is under evaluation in a long-term clinical trial across 8 dengue-endemic countries. Previously, we have reported its efficacy and safety in both seronegative and seropositive participants and that its performance varies by serotype, with some decline in efficacy from first to second year postvaccination. This exploratory analysis provides an update with cumulative and third-year data. METHODS: Healthy 4-16 year olds (n = 20099) were randomized 2:1 to receive TAK-003 or placebo (0, 3 month schedule). The protocol included baseline serostatus testing of all participants and detection of all symptomatic dengue throughout the trial with a serotype specific reverse transcriptase-polymerase chain reaction. RESULTS: Cumulative efficacy after 3 years was 62.0% (95% confidence interval, 56.6-66.7) against virologically confirmed dengue (VCD) and 83.6% (76.8-88.4) against hospitalized VCD. Efficacy was 54.3% (41.9-64.1) against VCD and 77.1% (58.6-87.3) against hospitalized VCD in baseline seronegatives, and 65.0% (58.9-70.1) against VCD and 86.0% (78.4-91.0) against hospitalized VCD in baseline seropositives. Efficacy against VCD during the third year declined to 44.7% (32.5-54.7), whereas efficacy against hospitalized VCD was sustained at 70.8% (49.6-83.0). Rates of serious adverse events were 2.9% in TAK-003 group and 3.5% in placebo group during the ongoing long-term follow-up (ie, second half of the 3 years following vaccination), but none were related. No important safety risks were identified. CONCLUSIONS: TAK-003 was efficacious against symptomatic dengue over 3 years. Efficacy declined over time but remained robust against hospitalized dengue. A booster dose evaluation is planned.