Laplace Transform Based Modeling of Drug Delivery with Reversible Drug Binding in a Multilayer Tissue.

OBJECTIVE: Drug delivery from a drug-loaded device into an adjacent tissue is a complicated process involving drug transport through diffusion and advection, coupled with drug binding kinetics responsible for drug uptake in the tissue. This work presents a theoretical model to predict drug delivery from a device into a multilayer tissue, assuming linear reversible drug binding in the tissue layers. METHODS: The governing mass conservation equations based on diffusion, advection and drug binding in a multilayer cylindrical geometry are written, and solved using Laplace transformation. The model is used to understand the impact of various non-dimensional parameters on the amounts of bound and unbound drug concentrations as functions of time. RESULTS: Good agreement for special cases considered in past work is demonstrated. The effect of forward and reverse binding reaction rates on the multilayer drug binding process is studied in detail. The effect of the nature of the external boundary condition on drug binding and drug loss is also studied. For typical parameter values, results indicate that only a small fraction of drug delivered binds in the tissue. Additionally, the amount of bound drug rises rapidly with time due to early dominance of the forward reaction, reaches a maxima and then decays due to the reverse reaction. CONCLUSIONS: The general model presented here can account for other possible effects such as drug absorption within the device. Besides generalizing past work on drug delivery modeling, this work also offers analytical tools to understand and optimize practical drug delivery devices.

Modeling Dual Drug Delivery from Eluting Stents: The Influence of Non-Linear Binding Competition and Non-Uniform Drug Loading.

OBJECTIVE: There is increasing interest in simultaneous endovascular delivery of more than one drug from a drug-loaded stent into a diseased artery. There may be an opportunity to obtain a therapeutically desirable uptake profile of the two drugs over time by appropriate design of the initial drug distribution in the stent. Due to the non-linear, coupled nature of diffusion and reversible specific/non-specific binding of both drugs as well as competition between the drugs for a fixed binding site density, a comprehensive numerical investigation of this problem is critically needed. METHODS: This paper presents numerical computation of dual drug delivery in a stent-artery system, accounting for diffusion as well as specific and non-specific reversible binding. The governing differential equations are discretized in space, followed by integration over time using a stiff numerical solver. Three different cases of initial dual drug distribution are considered. RESULTS: For the particular case of sirolimus and paclitaxel, results show that competition for a limited non-specific binding site density and the significant difference in the forward/backward reaction coefficients play a key role in determining the nature of drug uptake. The nature of initial distribution of the two drugs in the stent is also found to influence the binding process, which can potentially be used to engineer a desirable dual drug uptake profile. CONCLUSIONS: These results help improve the fundamental understanding of endovascular dual drug delivery. In addition, the numerical technique and results presented here may be helpful for designing and optimizing other drug delivery problems as well.

Oral Viscous Budesonide in Children With Eosinophilic Esophagitis After Repaired Esophageal Atresia: A Clinical Trial.

OBJECTIVES: A high prevalence of eosinophilic esophagitis (EoE) has been reported in children with repaired esophageal atresia (EA). Topical steroids proved to be an effective and safe therapy in EoE, although not approved in pediatrics. We report the results of the first clinical trial of oral viscous budesonide (OVB) performed in children with EoE after repaired esophageal atresia (EoE-EA). METHODS: This open-label, single-arm, phase 2 clinical trial with randomized pharmacokinetic sampling, was conducted at the Bambino Gesù Children's Hospital between September 2019 and June 2021. EoE-EA patients received an age-banded dose of OVB twice daily for 12 weeks and were endoscopically evaluated. The primary endpoint was the rate of patients achieving histological remission. Secondary endpoints included clinical and endoscopic benefit after treatment, and safety assessments. RESULTS: Eight consecutive EA-EoE patients were enrolled (median age 9.1 years, interquartile range 5.5). Of these, 5 received 0.8 mg and 3 received 1.0 mg twice daily of OVB. Histological remission was obtained in all but 1 patient (87.5%). The clinical score showed significant improvement at the end of treatment in all patients. No endoscopic features of EoE were found after treatment. No treatment-emergent adverse event occurred. CONCLUSION: OVB is an effective, safe, and well-tolerated formulation of budesonide for use in pediatric patients with EoE-EA.

Diagnosis of COVID-19 in children guided by lack of fever and exposure to SARS-CoV-2.

BACKGROUND: The objective of this study is to test how certain signs and symptoms related to COVID-19 in children predict the positivity or negativity of the SARS-CoV-2 nasopharyngeal swab in children. METHODS: We review the data of children who were tested for SARS-CoV-2 for a suspected infection. We compared the clinical characteristics of the subjects who tested positive and negative, including the sensibility, positive and negative predictive value of different combination of signs and symptoms. RESULTS: Of all the suspected infected, 2596 tested negative (96.2%) and 103 tested positive (3.8%). The median age was 7.0 and 5.3 years for the positive and negative ones, respectively. The female to male ratio was ~1:1.3. Fever and respiratory symptoms were mostly reported. Most positive children had a prior exposure to SARS-CoV-2-infected subjects (59.2%). A total of 99.3% of patients without fever nor exposure to the virus proved negative to the SARS-CoV-2 test. CONCLUSIONS: Our study suggests that a child without fever or contact with infected subjects is SARS-CoV-2 negative. If this were to be confirmed, many resources would be spared, with improved care of both COVID-19 and not COVID-19-affected children. IMPACT: Key message: lack of fever and exposure to SARS-CoV-2-infected people highly predicts a negative results of the SARS-CoV-2 nasopharyngeal swab in the paediatric population. Added value to the current literature: this is the first article to prove this point. IMPACT: reduction of emergency department accesses of children with suspected SARS-CoV-2 infection; increased outpatient management of children with cough or other common respiratory symptoms of infancy; sparing of many human and material health resources.

Model of drug delivery to populations composed of two cell types.

The rate of drug delivery to cells and the subsequent rate of drug metabolism are dependent on the cell membrane permeability to the drug. In some cases, tissue may be composed of different types of cells that exhibit order of magnitude differences in their membrane permeabilities. This paper presents a brief review of the components of the tissue scale three-compartment pharmacokinetic model of drug delivery to single-cell-type populations. The existing model is extended to consider tissue composed of two different cell types. A case study is presented of infusion mediated delivery of doxorubicin to a tumor that is composed of a drug reactive cell type and of a drug resistive cell type. The membrane permeabilities of the two cell types differ by an order of magnitude. A parametric investigation of the population composition is conducted and it is shown that the drug metabolism of the low permeability cells are negatively influenced by the fraction of the tissue composed of the permeable drug reactive cells. This is because when the population is composed mostly of drug permeable cells, the extracellular space is rapidly depleted of the drug. This has two compounding effects: (i) locally there is simply less drug available to the neighboring drug resistant cells, and (ii) the depletion of the drug from the extracellular space near the vessel-tissue interface leaves less drug to be transported to both cell types farther away from the vessel.

Optimization of Initial Drug Distribution in Spherical Capsules for Personalized Release.

OBJECTIVE: Customization of the rate of drug delivered based on individual patient requirements is of paramount importance in the design of drug delivery devices. Advances in manufacturing may enable multilayer drug delivery devices with different initial drug distributions in each layer. However, a robust mathematical understanding of how to optimize such capabilities is critically needed. The objective of this work is to determine the initial drug distribution needed in a spherical drug delivery device such as a capsule in order to obtain a desired drug release profile. METHODS: This optimization problem is posed as an inverse mass transfer problem, and optimization is carried out using the solution of the forward problem. Both non-erodible and erodible multilayer spheres are analyzed. Cases with polynomial forms of initial drug distribution are also analyzed. Optimization is also carried out for a case where an initial burst in drug release rate is desired, followed by a constant drug release rate. RESULTS: More than 60% reduction in root-mean-square deviation of the actual drug release rate from the ideal constant drug release rate is reported. Typically, the optimized initial drug distribution in these cases prevents or minimizes large drug release rate at early times, leading to a much more uniform drug release overall. CONCLUSIONS: Results demonstrate potential for obtaining a desired drug delivery profile over time by carefully engineering the drug distribution in the drug delivery device. These results may help engineer devices that offer customized drug delivery by combining advanced manufacturing with mathematical optimization.

Accuracy of serum procalcitonin for the diagnosis of sepsis in neonates and children with systemic inflammatory syndrome: a meta-analysis.

BACKGROUND: A number of biomarkers have been studied for the diagnosis of sepsis in paediatrics, but no gold standard has been identified. Procalcitonin (PCT) was demonstrated to be an accurate biomarker for the diagnosis of sepsis in adults and showed to be promising in paediatrics. Our study reviewed the diagnostic accuracy of PCT as an early biomarker of sepsis in neonates and children with suspected sepsis. METHODS: A comprehensive literature search was carried out in Medline/Pubmed, Embase, ISI Web of Science, CINAHL and Cochrane Library, for studies assessing PCT accuracy in the diagnosis of sepsis in children and neonates with suspected sepsis. Studies in which the presence of infection had been confirmed microbiologically or classified as "probable" by chart review were included. Studies comparing patients to healthy subjects were excluded. We analysed data on neonates and children separately. Our primary outcome was the diagnostic accuracy of PCT at the cut-off of 2-2.5 ng/ml, while as secondary outcomes we analysed PCT cut-offs <2 ng/ml and >2.5 ng/ml. Pooled sensitivities and specificities were calculated by a bivariate meta-analysis and heterogeneity was graphically evaluated. RESULTS: We included 17 studies, with a total of 1408 patients (1086 neonates and 322 children). Studies on neonates with early onset sepsis (EOS) and late onset sepsis (LOS) were grouped together. In the neonatal group, we calculated a sensitivity of 0.85, confidence interval (CI) (0.76; 0.90) and specificity of 0.54, CI (0.38; 0.70) at the PCT cut-off of 2.0-2.5 ng/ml. In the paediatric group it was not possible to undertake a pooled analysis at the PCT cut-off of 2.0-2.5 ng/ml, due to the paucity of the studies. CONCLUSIONS: PCT shows a moderate accuracy for the diagnosis of sepsis in neonates with suspected sepsis at the cut-off of 2.0-2.5 ng/ml. More studies with high methodological quality are warranted, particularly in neonates, studies considering EOS and LOS separately are needed to improve specificity. TRIAL REGISTRATION: PROSPERO Identifier: CRD42016033809 . Registered 30 Jan 2016.

Cognitive development in females with PCDH19 gene-related epilepsy.

Mutations in the PCDH19 gene are now recognized to cause epilepsy in females and are claiming increasing interest in the scientific world. Clinical features and seizure semiology have been described as heterogeneous. Intellectual disability might be present, ranging from mild to severe; behavioral and psychiatric problems are a common feature of the disorder, including aggressiveness, depressed mood, and psychotic traits. The purpose of our study was to describe the cognitive development in 11 girls with a de novo mutation in PCDH19 and early-onset epilepsy. Six patients had average mental development or mild intellectual disability regardless of persistence of seizures in clusters. Five patients presented moderate or severe intellectual disability and autistic features. In younger patients, we found that despite an average developmental quotient, they all presented a delay of expressive language acquisition and lower scores at follow-up testing completed at older ages, underlining that subtle dysfunctions might be present. Larger cohort and long-term follow-up might be useful in defining cognitive features and in improving the care of patients with PCDH19.

Soluble ligands for the NKG2D receptor are released during HIV-1 infection and impair NKG2D expression and cytotoxicity of NK cells.

In humans, the interaction of the natural killer group 2 member D (NKG2D)-activating receptor on natural killer (NK) and CD8(+) T cells with its major histocompatibility complex class I-related chain (MIC) and UL16 binding protein (ULBP) ligands (NKG2DLs) promotes recognition and elimination of stressed cells, such as tumor or infected cells. Here, we investigated the capacity of HIV-1 to modulate NKG2DL expression and escape NGK2D-mediated immunosurveillance. In CD4(+) T lymphocytes, both cell surface expression and release of MICA, MICB, and ULBP2 were up-regulated >2-fold by HIV-1 infection. In HIV-infected CD4(+) T lymphocytes or Jurkat T-cell lines, increased shedding of soluble NKG2DLs (sNKG2DLs) was impaired by a matrix metalloproteinase inhibitor (MMPI). Moreover, naive HIV(+) patients displayed increased plasma sMICA and sULBP2 levels and reduced NKG2D expression on NK and CD8(+) T cells compared to patients receiving highly active antiretroviral therapy (HAART) or healthy donors. In individual patients, HAART uptake resulted in the drop of sNKG2DL and recovery of NKG2D expression. Finally, sNKG2DLs in patients' plasma down-regulated NKG2D on NK and CD8(+) T cells and impaired NKG2D-mediated cytotoxicity of NK cells. Thus, NKG2D detuning by sNKG2DLs may promote HIV-1 immune evasion and compromise host resistance to opportunistic infections, but HAART and MMPI have the potential to avoid such immune dysfunction.

Layer-by-layer assembly of nanotheranostic particles for simultaneous delivery of docetaxel and doxorubicin to target osteosarcoma.

Osteosarcoma (OS) is a rare form of primary bone cancer, impacting approximately 3.4 × 106 individuals worldwide each year, primarily afflicting children. Given the limitations of existing cancer therapies, the emergence of nanotheranostic platforms has generated considerable research interest in recent decades. These platforms seamlessly integrate therapeutic potential of drug compounds with the diagnostic capabilities of imaging probes within a single construct. This innovation has opened avenues for enhanced drug delivery to targeted sites while concurrently enabling real-time monitoring of the vehicle's trajectory. In this study, we developed a nanotheranostic system employing the layer-by-layer (LbL) technique on a core containing doxorubicin (DOXO) and in-house synthesized carbon quantum dots. By utilizing chitosan and chondroitin sulfate as polyelectrolytes, we constructed a multilayered coating to encapsulate DOXO and docetaxel, achieving a coordinated co-delivery of both drugs. The LbL-functionalized nanoparticles exhibited an approximate size of 150 nm, manifesting a predominantly uniform and spherical morphology, with an encapsulation efficiency of 48% for both drugs. The presence of seven layers in these systems facilitated controlled drug release over time, as evidenced by in vitro release tests. Finally, the impact of the LbL-functionalized nanoparticles was evaluated on U2OS and Saos-2 osteosarcoma cells. The synergistic effect of the two drugs was found to be crucial in inducing cell death, particularly in Saos-2 cells treated with nanoparticles at concentrations higher than 10 µg/ml. Transmission electron microscopy analysis confirmed the internalization of the nanoparticles into both cell types through endocytic mechanisms, revealing an underlying mechanism of necrosis-induced cell death.

Nocturnal hypoglycaemia in ACTH and GH deficient children: role of continuous glucose monitoring.

OBJECTIVES: To evaluate the usefulness of continuous glucose monitoring (CGM) to identify nocturnal hypoglycaemia in children affected by combined ACTH and GH deficiency and to optimize the hydrocortisone replacement therapy in these patients. STUDY DESIGN: Eleven patients with ACTH and GH deficiency (five boys and six girls, age 1·6-16·8 years) underwent CGM for 36 h, including two nights. At least two consecutive glucose levels <2·78 mm were considered hypoglycaemic episodes. The differences in age and doses of hydrocortisone and recombinant human growth hormone (rhGH) between children with and without hypoglycaemia were analysed. The percentage of the glucose values <3·33 mm and the mean glucose levels were also evaluated. RESULTS: Continuous glucose monitoring demonstrated nocturnal hypoglycaemia lasting from 30 to 155 min (1·5% of the total monitoring time) in three cases (27%). No statistically significant differences in age and rhGH dose were observed between children with or without hypoglycaemia. Conversely, the difference in the hydrocortisone doses between the patients with and without hypoglycaemia resulted statistically significant (5·9 vs 8·5 mg/m²/day; P = 0·04). Eight patients presented glucose values less than 3·33 mm during 5% of the total monitoring time. Hydrocortisone dose showed significant positive linear relation with mean glucose level (r = 0·79, P = 0·0035) and inverse relation with time lags of glucose levels under 3·33 mm (r = -0·65, P = 0·03). CONCLUSIONS: Our study shows that CGM may represent a valuable tool to detect nocturnal asymptomatic hypoglycaemic episodes and optimize the hydrocortisone therapeutic regimen in children with ACTH and GH deficiency.

Raising awareness of non-Hodgkin lymphoma in HIV-infected adolescents: report of 2 cases in the HAART era.

Human immunodeficiency virus (HIV) chronically infected patients are at increased risk of developing non-Hodgkin lymphoma compared with the general population. Highly active antiretroviral therapy has had a dramatic effect on the natural history of HIV infection, reducing the incidence of acquired immunodeficiency syndrome-related non-Hodgkin lymphoma and improving overall survival. However, problems related to adherence to treatment, frequently experienced during adolescence, may increase the risk of acquired immunodeficiency syndrome-related cancers. Optimizing highly active antiretroviral therapy and monitoring noncompliant patients with persisting HIV replication should be considered by physicians who take care of these patients. We herein report 2 cases of relapsed/progressive Burkitt lymphoma in HIV vertically infected adolescents.

Video/EEG findings in a KCNQ2 epileptic encephalopathy: a case report and revision of literature data.

We describe the EEG findings of an infant with early-onset epileptic encephalopathy with mutation of the KCNQ2 gene and a family history of neonatal seizures. The infant presented with multifocal drug-resistant seizures with onset during the third day of life. Family history was positive for early-onset neonatal seizures. Metabolic screening and neuroimaging were negative. Direct sequencing of KCQN2 from both the mother and child revealed a heterozygous cytosine-to-guanine mutation (Dedek et al., 2003). Interictal EEG showed a very discontinuous pattern which evolved towards a defined burst-suppression pattern during sleep and a multifocal, random, attenuation pattern during wakefulness. Focal, tonic seizures with head deviation, sometimes followed by asynchronous and asymmetrical clonic jerks, eyelid myoclonias, and polypnoea, were recorded. Ictal EEG was characterised by focal, low-voltage, fast activity, followed by recruiting theta rhythms and bilateral, focal, spike-wave complexes, alternatively localised to one hemisphere and subsequently diffusing to the other. ACTH therapy was introduced, resulting in a significant improvement in EEG activity and gradual reduction in seizure frequency, with cessation at age 13 weeks. [Published with video sequences].

Modelling smart drug release with functionally graded materials.

Functionally graded materials (FGMs), possessing properties that vary smoothly from one region to another, have been receiving increasing attention in recent years, particularly in the aerospace, automotive and biomedical sectors. However, they have yet to reach their full potential. In this paper, we explore the potential of FGMs in the context of drug delivery, where the unique material characteristics offer the potential of fine-tuning drug-release for the desired application. Specifically, we develop a mathematical model of drug release from a thin film FGM, based upon a spatially-varying drug diffusivity. We demonstrate that, depending on the functional form of the diffusivity (related to the material properties) a wide range of drug release profiles may be obtained. Interestingly, the shape of these release profiles are not, in general, achievable from a homogeneous medium with a constant diffusivity.

Participant Recruitment Issues in Child and Adolescent Psychiatry Clinical Trials with a Focus on Prevention Programs: A Meta-Analytic Review of the Literature.

Introduction: There is a strong need to conduct rigorous and robust trials for children and adolescents in mental health settings. One of the main barriers to meeting this requirement is the poor recruitment rate. Effective recruitment strategies are crucial for the success of a clinical trial, and therefore, we reviewed recruitment strategies in clinical trials on children and adolescents in mental health with a focus on prevention programs. Methods: We reviewed the literature by searching PubMed/Medline, the Cochrane Library database, and Web of Science through December 2022 as well as the reference lists of relevant articles. We included only studies describing recruitment strategies for pediatric clinical trials in mental health settings and extracted data on recruitment and completion rates. Results: The search yielded 13 studies that enrolled a total of 14,452 participants. Overall, studies mainly used social networks or clinical settings to recruit participants. Half of the studies used only one recruitment method. Using multiple recruitment methods (56.6%, 95%CI: 24.5-86.0) resulted in higher recruitment. The use of monetary incentives (47.0%, 95%CI: 24.6-70.0) enhanced the recruitment rate but not significantly (32.6%, 95%CI: 15.7-52.1). All types of recruitment methods showed high completion rates (82.9%, 95%CI: 61.7-97.5) even though prevention programs showed the smallest recruitment rate (76.1%, 95%CI: 50.9-94.4). Conclusions: Pediatric mental health clinical trials face many difficulties in recruitment. We found that these trials could benefit from faster and more efficient recruitment of participants when more than one method is implemented. Social networks can be helpful where ethically possible. We hope the description of these strategies will help foster innovation in recruitment for pediatric studies in mental health.

Controlling release from encapsulated drug-loaded devices: insights from modeling the dissolution front propagation.

Dissolution of drug from its solid form to a dissolved form is an important consideration in the design and optimization of drug delivery devices, particularly owing to the abundance of emerging compounds that are extremely poorly soluble. When the solid dosage form is encapsulated, for example by the porous walls of an implant, the impact of the encapsulant drug transport properties is a further confounding issue. In such a case, dissolution and diffusion work in tandem to control the release of drug. However, the interplay between these two competing processes in the context of drug delivery is not as well understood as it is for other mass transfer problems, particularly for practical controlled-release considerations such as an encapsulant layer around the drug delivery device. To address this gap, this work presents a mathematical model that describes controlled release from a drug-loaded device surrounded by a passive porous layer. A solution for the drug concentration distribution is derived using the method of eigenfunction expansion. The model is able to track the dissolution front propagation, and predict the drug release curve during the dissolution process. The utility of the model is demonstrated through comparison against experimental data representing drug release from a cylindrical drug-loaded orthopedic fixation pin, where the model is shown to capture the data very well. Analysis presented here reveals how the various geometrical and physicochemical parameters influence drug dissolution and, ultimately, the drug release profile. It is found that the non-dimensional initial concentration plays a key role in determining whether the problem is diffusion-limited or dissolution-limited, whereas the nature of the problem is largely independent of other parameters including diffusion coefficient and encapsulant thickness. We expect the model will prove to be a useful tool for those designing encapsulated drug delivery devices, in terms of optimizing the design of the device to achieve a desired drug release profile.

EPI-743 reverses the progression of the pediatric mitochondrial disease--genetically defined Leigh Syndrome.

BACKGROUND: Genetically defined Leigh syndrome is a rare, fatal inherited neurodegenerative disorder that predominantly affects children. No treatment is available. EPI-743 is a novel small molecule developed for the treatment of Leigh syndrome and other inherited mitochondrial diseases. In compassionate use cases and in an FDA Expanded Access protocol, children with Leigh syndrome treated with EPI-743 demonstrated objective signs of neurologic and neuromuscular improvement. To confirm these initial findings, a phase 2A open label trial of EPI-743 for children with genetically-confirmed Leigh syndrome was conducted and herein we report the results. METHODS: A single arm clinical trial was performed in children with genetically defined Leigh syndrome. Subjects were treated for 6 months with EPI-743 three times daily and all were eligible for a treatment extension phase. The primary objective of the trial was to arrest disease progression as assessed by neuromuscular and quality of life metrics. Results were compared to the reported natural history of the disease. RESULTS: Ten consecutive children, ages 1-13 years, were enrolled; they possessed seven different genetic defects. All children exhibited reversal of disease progression regardless of genetic determinant or disease severity. The primary endpoints--Newcastle Pediatric Mitochondrial Disease Scale, the Gross Motor Function Measure, and PedsQL Neuromuscular Module--demonstrated statistically significant improvement (p<0.05). In addition, all children had an improvement of one class on the Movement Disorder-Childhood Rating Scale. No significant drug-related adverse events were recorded. CONCLUSIONS: In comparison to the natural history of Leigh syndrome, EPI-743 improves clinical outcomes in children with genetically confirmed Leigh syndrome.

A survey on hematology-oncology pediatric AIEOP centers: prophylaxis, empirical therapy and nursing prevention procedures of infectious complications.

A nationwide questionnaire-based survey was designed to evaluate the management and prophylaxis of febrile neutropenia in pediatric patients admitted to hematology-oncology and hematopoietic stem cell transplant units. Of the 34 participating centers, 40 and 63%, respectively, continue to prescribe antibacterial and antimycotic prophylaxis in low-risk subjects and 78 and 94% in transplant patients. Approximately half of the centers prescribe a combination antibiotic regimen as first-line therapy in low-risk patients and up to 81% in high-risk patients. When initial empirical therapy fails after seven days, 63% of the centers add empirical antimycotic therapy in low-and 81% in high-risk patients. Overall management varies significantly across centers. Preventive nursing procedures are in accordance with international guidelines. This survey is the first to focus on prescribing practices in children with cancer and could help to implement practice guidelines.

Renal function in HIV-infected children and adolescents treated with tenofovir disoproxil fumarate and protease inhibitors.

BACKGROUND: Kidney disease is an important complication in HIV infected people, and this may be related to infection or antiretroviral therapy (ART). Our aim is to assess renal function in HIV infected paediatric patients, who may be particularly affected and are likely to take ART for longer than adults, and investigate the long term role of Tenofovir Disoproxil Fumarate (TDF) alone or co-administered with Ritonavir-boosted Protease Inhibitors (PI). METHODS: Serum creatinine, phosphate and potassium levels, with estimated Glomerular Filtration Rate (eGFR), had been prospectively evaluated for 2 years in a cohort of HIV infected children and adolescents (age 9-18) on ART, and data analyzed according to the exposure to TDF or simultaneous TDF and PI. RESULTS: Forty-nine patients were studied (57% female, mean age 14). Sixty-three percent were treated with ART containing TDF (Group A), and 37% without TDF (Group B); 47% with concomitant use of TDF and PI (Group C) and 53% without this combination (Group D). The groups didn't differ for age, gender or ethnicity. The median creatinine increased in the entire cohort and in all the groups analyzed; eGFR decreased from 143.6 mL/min/1.73 m2 at baseline to 128.9 after 2 years (p = 0.006) in the entire cohort. Three patients presented a mild eGFR reduction, all were on TDF+PI. Phosphatemia decreased significantly in the entire cohort (p = 0.0003) and in TDF+PI group (p = 0.0128) after 2 years. Five patients (10%) developed hypophosphatemia (Division of Acquired Immune Deficiency AE grade 1 or 2), and four of them were on TDF+PI. CONCLUSIONS: Renal function decrease and hypophosphatemia occur over time in HIV infected children and adolescents on ART. The association with co-administration of TDF and PI appears weak, and further studies are warranted.

Safety and immunogenicity of a monovalent MF59®-adjuvanted A/H1N1 vaccine in HIV-infected children and young adults.

BACKGROUND: This Phase IV study evaluated the safety and immunogenicity of a two-dose, MF59®-adjuvanted (Novartis Vaccines, Marburg, Germany), monovalent, A/H1N1 pandemic influenza vaccination schedule in Human Immunodeficiency Virus (HIV) positive children and young adults. METHODS: A total of 83 children infected with HIV-1, and 37 non-immunocompromised, age-matched controls were enrolled. All participants received two vaccine doses administered three weeks apart. Antibody responses were assessed by haemagglutination assay at baseline, three weeks after each vaccine dose, and six months after immunization. Vaccines were evaluated according to European influenza vaccine licensure criteria. RESULTS: The investigational vaccine was well tolerated. After the first vaccine dose, seroconversion rates were significantly lower in HIV-positive patients (60%) than controls (82%), with GMTs of 419 and 600, respectively. No significant differences in seroconversion rates were observed between the two study groups in response to the second vaccine dose. Persisting antibody titers were similar for both HIV-positive and non-infected controls, six months after immunization. CONCLUSION: One dose of MF59-adjuvanted vaccine was sufficient to provide adequate levels of seroprotection against A/H1N1 influenza disease in HIV-positive children. However, a two-dose vaccination schedule may be optimal for this population.