Population pharmacokinetics and dosing recommendations for the use of deferiprone in children younger than 6 years

AIMS: Despite long clinical experience with deferiprone, there is limited information on its pharmacokinetics in children < 6 years of age. Here we assess the impact of developmental growth on the pharmacokinetics of deferiprone in this population using a population approach. Based on pharmacokinetic bridging concepts, we also evaluate whether the recommended doses yield appropriate systemic exposure in this group of patients. METHODS: Data from a study in which 18 paediatric patients were enrolled were available for the purposes of this analysis. Patients were randomised to three deferiprone dose levels (8.3, 16.7 and 33.3 mg/kg). Blood samples were collected according to an optimised sampling scheme in which each patient contributed to a maximum of five samples. A population pharmacokinetic model was developed using NONMEM v.7.2. Model selection criteria were based on graphical and statistical summaries. RESULTS: A one-compartment model with first-order absorption and first-order elimination best described the pharmacokinetics of deferiprone. Drug disposition parameters were affected by body weight, with both clearance and volume increasing allometrically with size. Simulation scenarios show that comparable systemic exposure (AUC) is achieved in children and adults after similar dose levels in mg/kg, with median (5-95(th) quantiles) AUC values respectively of 340.6 (223.2-520.0) and 318.5 (200.4-499.0) µmol/L*h at 75 mg/kg/day and 453.7 (297.3-693.0) and 424.2 (266.9-664.0) at 100 mg/kg/day t.i.d. doses. CONCLUSIONS: Based on the current findings, a dosing regimen of 25 mg/kg t.i.d. is recommended in children below 6 years of age, with the possibility of titration up to 33.3 mg/kg t.i.d

Rectal indomethacin alone versus indomethacin and prophylactic pancreatic stent placement for preventing pancreatitis after ERCP: study protocol for a randomized controlled trial

Abstract Background The combination of prophylactic pancreatic stent placement (PSP) – a temporary plastic stent placed in the pancreatic duct – and rectal non-steroidal anti-inflammatory drugs (NSAIDs) is recommended for preventing post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) in high-risk cases. Preliminary data, however, suggest that PSP may be unnecessary if rectal NSAIDs are administered. Given the costs and potential risks of PSP, we aim to determine whether rectal indomethacin obviates the need for pancreatic stent placement in patients undergoing high-risk ERCP. Methods/Design The SVI (Stent vs. Indomethacin) trial is a comparative effectiveness, multicenter, randomized, double-blind, non-inferiority study of rectal indomethacin alone versus the combination of rectal indomethacin and PSP for preventing PEP in high-risk cases. One thousand four hundred and thirty subjects undergoing high-risk ERCP, in whom PSP is planned solely for PEP prevention, will be randomized to indomethacin alone or combination therapy. Those who are aware of study group assignment, including the endoscopist, will not be involved in the post-procedure care of the patient for at least 48 hours. Subjects will be assessed for PEP and its severity by a panel of independent and blinded adjudicators. Indomethacin alone will be declared non-inferior to combination therapy if the two-sided 95 % upper confidence bound of the treatment difference is less than 5 % between the two groups. Biological specimens will be obtained from trial participants and centrally banked. Discussion The SVI trial is designed to determine whether PSP remains necessary in the era of NSAIDs pharmacoprevention. The associated bio-repository will establish the groundwork for important scientific breakthrough. Trial registration NCT02476279, registered June 2015

Rectal indomethacin alone versus indomethacin and prophylactic pancreatic stent placement for preventing pancreatitis after ERCP: Study protocol for a randomized controlled trial

Background: The combination of prophylactic pancreatic stent placement (PSP) - a temporary plastic stent placed in the pancreatic duct - and rectal non-steroidal anti-inflammatory drugs (NSAIDs) is recommended for preventing post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) in high-risk cases. Preliminary data, however, suggest that PSP may be unnecessary if rectal NSAIDs are administered. Given the costs and potential risks of PSP, we aim to determine whether rectal indomethacin obviates the need for pancreatic stent placement in patients undergoing high-risk ERCP. Methods/Design: The SVI (Stent vs. Indomethacin) trial is a comparative effectiveness, multicenter, randomized, double-blind, non-inferiority study of rectal indomethacin alone versus the combination of rectal indomethacin and PSP for preventing PEP in high-risk cases. One thousand four hundred and thirty subjects undergoing high-risk ERCP, in whom PSP is planned solely for PEP prevention, will be randomized to indomethacin alone or combination therapy. Those who are aware of study group assignment, including the endoscopist, will not be involved in the post-procedure care of the patient for at least 48 hours. Subjects will be assessed for PEP and its severity by a panel of independent and blinded adjudicators. Indomethacin alone will be declared non-inferior to combination therapy if the two-sided 95 % upper confidence bound of the treatment difference is less than 5 % between the two groups. Biological specimens will be obtained from trial participants and centrally banked. Discussion: The SVI trial is designed to determine whether PSP remains necessary in the era of NSAIDs pharmacoprevention. The associated bio-repository will establish the groundwork for important scientific breakthrough