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Paediatric abacavir-lamivudine fixed-dose dispersible tablets and ritonavir-boosted lopinavir granules in neonates exposed to HIV (PETITE study): an open-label, two-stage, single-arm, phase 1/2, pharmacokinetic and safety trial

Bekker, Adrie; Salvadori, Nicolas; Rabie, Helena; du Toit, Samantha; Than-In-At, Kanchana; Groenewald, Marisa; Cressey, Ratchada; Nielsen, James; Capparelli, Edmund V; Lallemant, Marc; Cotton, Mark F; Cressey, Tim R; ,
BACKGROUND:Existing solid antiretroviral fixed-dose combination formulations are preferred over liquid formulations in children, but their suitability for neonates is unknown. We evaluated the pharmacokinetics and safety of paediatric abacavir-lamivudine fixed-dose dispersible tablets and ritonavir-boosted lopinavir granules in neonates. METHODS:In this open-label, two-stage, single-arm, phase 1/2, pharmacokinetic and safety trial, generic abacavir- lamivudine (120:60 mg) double-scored dispersible tablets and lopinavir boosted with ritonavir (40:10 mg) granules were studied. Neonates exposed to HIV (≥37 weeks gestational age) of no more than 3 days of age with birthweights of 2000-4000 g were identified through routine care in a tertiary hospital in Cape Town, South Africa. In stage 1, the pharmacokinetics and safety of two single doses were assessed to select the multidose strategy for stage 2. Neonates received a single dose of abacavir-lamivudine (30:15 mg, a quarter of a tablet) and lopinavir boosted with ritonavir (40:10 mg - one sachet) orally between 3 days and 14 days of age, and a second dose of a quarter tablet of abacavir-lamivudine and lopinavir boosted with ritonavir (80:20 mg, two sachets) 10-14 days later in stage 1. The multidose strategy selected in stage 2 was a quarter of the abacavir-lamivudine (30:15 mg) fixed-dose dispersible tablet once per day and two sachets of the lopinavir boosted with ritonavir (80:20 mg) granules twice per day from birth to age 28 days. In both stages two intensive pharmacokinetic visits were done, one at less than 14 days of life (pharmacokinetics 1) and another 10-14 days later (pharmacokinetics 2). Safety visits were done 1-2 weeks after each pharmacokinetic visit. Primary objectives were to assess pharmacokinetics and safety of abacavir, lamivudine, and lopinavir. Pharmacokinetic endpoints were area under the concentration time curve (AUC), maximum concentration, and concentration at end of dosing interval in all participants with at least one evaluable pharmacokinetic visit. Safety endpoints included grade 3 or worse adverse events, and grade 3 or worse treatment-related adverse events, occurring between study drug initiation and end of study. This completed trial is registered with the Pan African Clinical Trials Registry (PACTR202007806554538). FINDINGS/RESULTS:) were higher at 6-14 days (51·7 mg × h/L for abacavir and 17·2 mg × h/L for lamivudine) than at 19-24 days of age (25·0 mg × h/L and 11·3 mg × h/L), whereas they were similar for lopinavir over this period (AUC 0-12 58·5 mg × h/L vs 46·4 mg × h/L). Abacavir geometric mean AUC0-24 crossed the upper reference range at pharmacokinetics 1, but rapidly decreased. Lamivudine and lopinavir AUC0-tau were within range. No grade 2 or worse adverse events were related to study drugs. One neonate had a grade 1 prolonged corrected QT interval using the Fridericia method that spontaneously resolved. INTERPRETATION/CONCLUSIONS:Abacavir-lamivudine dispersible tablets and ritonavir-boosted lopinavir granules in neonates were safe and provided drug exposures similar to those in young infants. Although further safety data are needed, this regimen presents a new option for HIV prevention and treatment from birth. Accelerating neonatal pharmacokinetic studies of novel antiretroviral therapies is essential for neonates to also benefit from state-of-the-art treatments. FUNDING/BACKGROUND:Unitaid.
PMID: 38296364
ISSN: 2352-3018
CID: 5627162

Pharmacokinetics and safety of the abacavir/lamivudine/lopinavir/ritonavir fixed-dose granule formulation (4-in-1) in neonates: PETITE study

Bekker, Adrie; Rabie, Helena; Salvadori, Nicolas; du Toit, Samantha; Than-In-At, Kanchana; Groenewald, Marisa; Andrieux-Meyer, Isabelle; Kumar, Mukesh; Cressey, Ratchada; Nielsen, James; Capparelli, Edmund; Lallemant, Marc; Cotton, Mark F; Cressey, Tim R
BACKGROUND:Antiretroviral options for neonates (< 28 days of life) should be expanded. We evaluated the pharmacokinetics, safety, and acceptability of the '4-in-1' fixed-dose paediatric granule formulation of abacavir/lamivudine/lopinavir/ritonavir (30/15/40/10 mg) in neonates. METHODS:The PETITE study is an ongoing phase I/II, open-label, single arm, two-stage trial conducted in South Africa. In Stage 1, term neonates exposed to HIV on standard antiretroviral prophylaxis (nevirapine +/- zidovudine) received single dose(s) of the 4-in-1 formulation followed by intensive pharmacokinetic sampling and safety assessments. At each PK visit, blood was drawn following an observed dose at 1, 2, 4, 8- and 12-hours post-dose. Here, we report the planned interim pharmacokinetic and safety analysis after completion of the single dose administration. RESULTS:Sixteen neonates, median (range) birth weight 3130 (2790-3590) g, completed 24 pharmacokinetic visits. The 4-in-1 imposed relatively high mg/kg doses of abacavir 8.6 (6.6-11.4) and lamivudine 4.3 (3.3-5.7), but lower lopinavir doses of 11.5 (8.8-15.2). Geometric mean (GM, 90% CI) AUC0-12 of abacavir, lamivudine and lopinavir were 29.87 (26.29-33.93), 12.61 (10.72-14.83) and 3.49 (2.13-5.72) µg.hr/mL, respectively. Lopinavir GM AUC0-12 was below the predefined target (20-100 µg.hr/mL) and ritonavir concentrations were only detectable in 4/120 (3%) samples. No adverse events were related to study drugs. No neonate had difficulty swallowing the 4-in-1. CONCLUSION/CONCLUSIONS:The high mg/kg abacavir and lamivudine doses and AUCs were safe, and the formulation well tolerated; however, lopinavir/ritonavir exposures were extremely low, preventing its use in neonates. Alternative paediatric solid antiretroviral formulations must be studied in neonates.
PMID: 34855626
ISSN: 1944-7884
CID: 5065812

Optimal radiologic position of an umbilical venous catheter tip as determined by echocardiography in very low birth weight newborns

Karber, B C F; Nielsen, J C; Balsam, D; Messina, C; Davidson, D
OBJECTIVE: To compare chest X-ray with echocardiogram (ECHO) in the localization of an umbilical venous catheter (UVC) tip in very low birth weight infants (VLBW). Secondary objectives determined the association between techniques for tip placement by the vertebral body level on X-ray, as well as the length of the thoracic inferior vena cava-right atrial (TIVC-RA) junction by ECHO. STUDY DESIGN: Prospective, sequentially enrolled, masked, single regional perinatal center study. Shortly after birth, one or more anterior-posterior X-rays were ordered by the clinical team to verify that the UVC tip was fixed in the central right atrium (cRA) or at the TIVC-RA junction. An echocardiogram was performed as soon as possible after the last X-ray and UVC tip location was interpreted by a pediatric cardiologist. The pediatric radiologist and cardiologist were masked with regard to each other's reading. RESULTS: The newborns (n = 51) were 27 (+/-3) weeks by gestational age with birth weights of 1029 (+/-288) grams (mean+/-SD). The radiologist read 50 UVC tips (98%) in the cRA or TIVC-RA junction and 1 (2%) in the LA. The cardiologist read 22 (43%) in the cRA or TIVC-RA, 21 (41%) in the LA and 8 (16%) tips could not be located in the heart. When the UVC tip was interpreted by X-ray as located in the TIVC-RA junction 8/29 (28%) were in the LA by echocardiogram. There was no agreement between vertebral level and tip position in the TIVC-RA junction, RA or LA. The TIVC-RA junction measured 6+/-1 mm and correlated with birth weight r = 0.54 (p < 0.001). CONCLUSION: In VLBW newborns, placement of the UVC tip into the cRA or TIVC-RA junction by X-ray does not avoid misplacement in the left atrium as demonstrated by echocardiography. For VLBW infants, it is suggested that echocardiography may be helpful in verifying that the original placement or migration of the UVC tip into the LA has not occurred.
PMID: 28304320
ISSN: 1878-4429
CID: 2726752

Pharmacokinetics and cardiac safety of clofazimine in children with rifampicin-resistant tuberculosis

Ali, Ali Mohamed; P Solans, Belén; Hesseling, Anneke C; Winckler, Jana; Schaaf, H Simon; Draper, Heather R; van der Laan, Louvina; Hughes, Jennifer; Fourie, Barend; Nielsen, James; Wiesner, Lubbe; Garcia-Prats, Anthony J; Savic, Radojka M
Clofazimine is recommended for the treatment of rifampicin-resistant tuberculosis (RR-TB), but there is currently no verified dosing guideline for its use in children. There is only limited safety and no pharmacokinetic (PK) data available for children. We aimed to characterize clofazimine PK and its relationship with QT-interval prolongation in children. An observational cohort study of South African children <18 years old routinely treated for RR-TB with a clofazimine-containing regimen was analyzed. Clofazimine 100 mg gelatin capsules were given orally once daily (≥20 kg body weight), every second day (10 to <20 kg), or thrice weekly (<10 kg). PK sampling and electrocardiograms were completed pre-dose and at 1, 4, and 10 hours post-dose, and the population PK and Fridericia-corrected QT (QTcF) interval prolongation were characterized. Fifty-four children contributed both PK and QTcF data, with a median age (2.5th-97.5th centiles) of 3.3 (0.5-15.6) years; five children were living with HIV. Weekly area under the time-concentration curve at steady state was 79.1 (15.0-271) mg.h/L compared to an adult target of 60.9 (56.0-66.6) mg.h/L. Children living with HIV had four times higher clearance compared to those without. No child had a QTcF ≥500 ms. A linear concentration-QTcF relationship was found, with a drug effect of 0.05 (0.027, 0.075) ms/µg/L. In some of the first PK data in children, we found clofazimine exposure using an off-label dosing strategy was higher in children versus adults. Clofazimine concentrations were associated with an increase in QTcF, but severe prolongation was not observed. More data are required to inform dosing strategies in children.
PMID: 38112526
ISSN: 1098-6596
CID: 5612332

QT Interval Prolongation with One or More QT-Prolonging Agents Used as Part of a Multidrug Regimen for Rifampicin-Resistant Tuberculosis Treatment: Findings from Two Pediatric Studies

Ali, Ali Mohamed; Radtke, Kendra K; Hesseling, Anneke C; Winckler, Jana; Schaaf, H Simon; Draper, Heather R; Solans, Belén P; van der Laan, Louvina; Hughes, Jennifer; Fourie, Barend; Nielsen, James; Garcia-Prats, Anthony J; Savic, Rada M
Rifampicin-resistant tuberculosis (RR-TB) involves treatment with many drugs that can prolong the QT interval; this risk may increase when multiple QT-prolonging drugs are used together. We assessed QT interval prolongation in children with RR-TB receiving one or more QT-prolonging drugs. Data were obtained from two prospective observational studies in Cape Town, South Africa. Electrocardiograms were performed before and after drug administration of clofazimine (CFZ), levofloxacin (LFX), moxifloxacin (MFX), bedaquiline (BDQ), and delamanid. The change in Fridericia-corrected QT (QTcF) was modeled. Drug and other covariate effects were quantified. A total of 88 children with a median (2.5th-to-97.5th range) age of 3.9 (0.5 to 15.7) years were included, of whom 55 (62.5%) were under 5 years of age. A QTcF interval of >450 ms was observed in 7 patient-visits: regimens were CFZ+MFX (n = 3), CFZ+BDQ+LFX (n = 2), CFZ alone (n = 1), and MFX alone (n = 1). There were no events with a QTcF interval of >500 ms. In a multivariate analysis, CFZ+MFX was associated with a 13.0-ms increase in change in QTcF (P < 0.001) and in maximum QTcF (P = 0.0166) compared to those when other MFX- or LFX-based regimens were used. In conclusion, we found a low risk of QTcF interval prolongation in children with RR-TB who received at least one QT-prolonging drug. Greater increases in maximum QTcF and ΔQTcF were observed when MFX and CFZ were used together. Future studies characterizing exposure-QTcF responses in children will be helpful to ensure safety with higher doses if required for effective treatment of RR-TB.
PMCID:10353402
PMID: 37358463
ISSN: 1098-6596
CID: 5535162

QT Interval Prolongation and Second-line Antituberculosis Medicines in Children: An Update and Practical Considerations for Noncardiologists

Hughes, Jennifer; Nielsen, James; Buck, W Chris; Mutemba, Criménia; Garcia-Prats, Anthony J
PMID: 36749926
ISSN: 1532-0987
CID: 5415522

Moxifloxacin pharmacokinetics, cardiac safety, and dosing for the treatment of rifampicin-resistant tuberculosis in children

Radtke, Kendra K; Hesseling, Anneke C; Winckler, J L; Draper, Heather R; Solans, Belen P; Thee, Stephanie; Wiesner, Lubbe; van der Laan, Louvina E; Fourie, Barend; Nielsen, James; Schaaf, H Simon; Savic, Radojka M; Garcia-Prats, Anthony J
BACKGROUND:Moxifloxacin is a priority recommended drug for rifampin-resistant tuberculosis (RR-TB) treatment, but there is limited pediatric pharmacokinetic and safety data, especially in young children. We characterize moxifloxacin population pharmacokinetics, QT-interval prolongation and evaluate optimal dosing in children with RR-TB. METHODS:Pharmacokinetic data were pooled from two observational studies in South African children 0-17 years of age with RR-TB routinely treated with oral moxifloxacin once daily. The population pharmacokinetics and Fridericia-corrected QT (QTcF)-interval prolongation were characterized in NONMEM. Pharmacokinetic simulations were performed to predict expected exposure and optimal weight-banded dosing. RESULTS:Eighty-five children contributed pharmacokinetic data (median [range] age of 4.6 [0.8-15] years); 16 (19%) were <2 years of age, and 8 (9%) were HIV-positive. The median (range) moxifloxacin dose on pharmacokinetic sampling days was 11 mg/kg (6.1 to 17). Apparent clearance was 6.95 L/h for a typical 16 kg child. Stunting and HIV infection increased apparent clearance. Crushed or suspended tablets had faster absorption. The median (range) maximum change in QTcF after moxifloxacin administration was 16.3 (-27.7 to 61.3) ms. No child had QTcF ≥ 500 ms. The concentration-QTcF relationship was nonlinear, with a maximum drug effect (Emax) of 8.80 ms (inter-individual variability = 9.75 ms). Clofazimine use increased Emax by 3.3-fold. Model-based simulations of moxifloxacin pharmacokinetics predicted that current dosing recommendations are too low in children. CONCLUSIONS:Moxifloxacin doses above 10-15 mg/kg are likely required in young children to match adult exposures but require further safety assessment, especially when co-administered with other QT-prolonging agents.
PMID: 34286843
ISSN: 1537-6591
CID: 5068692

Periscopic technique in Norwood operation is associated with better preservation of early ventricular function

Bhatla, Puneet; Kumar, Tk Susheel; Makadia, Luv; Winston, Brandon; Bull, Catherine; Nielsen, James C; Williams, David; Chakravarti, Sujata; Ohye, Richard G; Mosca, Ralph S
Objective/UNASSIGNED:Although the right ventricle (RV) to pulmonary artery conduit in stage 1 Norwood operation results in improved interstage survival, the long-term effects of the ventriculotomy used in the traditional technique remain a concern. The periscopic technique (PT) of RV to pulmonary artery conduit placement has been described as an alternative technique to minimize RV injury. A retrospective study was performed to compare the effects of traditional technique and PT on ventricular function following Norwood operation. Methods/UNASSIGNED:A retrospective study of all patients who underwent Norwood operation from 2012 to 2019 was performed. Patients with baseline RV dysfunction and significant tricuspid valve regurgitation were excluded. Prestage 2 echocardiograms were reviewed by a blinded experienced imager for quantification of RV function (sinus and infundibular RV fractional area change) as well as for regional conduit site wall dysfunction (normal or abnormal, including hypokinesia, akinesia, or dyskinesia). Wilcoxon rank-sum tests were used to assess differences in RV infundibular and RV sinus ejection fraction and the Fisher exact test was used to assess differences in regional wall dysfunction. Results/UNASSIGNED: = .002). Conclusions/UNASSIGNED:The PT for RV to pulmonary artery conduit in Norwood operation results in better preservation of early RV global and regional systolic function. Whether or not this benefit translates to improved clinical outcome still needs to be studied.
PMCID:8350951
PMID: 34401829
ISSN: 2666-2507
CID: 4989292

Surgical Management of Giant Intrapericardial Teratoma Encasing the Coronary Artery

Minocha, Prashant; Hodzic, Emina; Sharma, Madhu; Bhatla, Puneet; Nielsen, James; Ramirez, Michelle; Magid, Margret; Fisher, Jason C; Mosca, Ralph; Kumar, Tk Susheel
Intrapericardial teratomas are rare, predominantly benign tumors that warrant surgical resection in the neonatal period because of their potential detrimental effects on the cardiorespiratory system. Surgical resection can be a challenge when the tumor encases and obscures a coronary artery. Adherence to certain operative principles is necessary to achieve successful outcomes.
PMID: 33888026
ISSN: 2150-136x
CID: 4852092

Diagnosis of anomalous origin of the right subclavian artery from the right pulmonary artery in a patient with D-transposition of the great arteries utilizing transthoracic echocardiography

Makadia, Luv D; Nielsen, James C; Kumar, Thittamaranahalli Kumar Susheel; Bhatla, Puneet
Diagnosis of anomalous origin of the right subclavian artery (AORSA) from the right pulmonary artery (RPA) is usually made using CT, MRI, or invasive angiography. We report a patient diagnosed using transthoracic echocardiography (TTE). A newborn girl prenatally known to have d-TGA presented with cyanosis sparing the right hemithorax and arm. Oxygen saturations on the right hand were persistently higher than on the right ear and other extremities. Repeat TTE using a modified echocardiographic imaging plane allowed for full visualization of the entire subclavian artery course, revealing AORSA from RPA. We discuss further the approach to echocardiographic diagnosis and surgical implications.
PMID: 33084030
ISSN: 1540-8175
CID: 4671102