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Background: The pharmacodynamics of propofol in children have previously been described with the proprietary bispectral index (BIS) as an effect‐site marker, and it has been suggested that the rate of onset of propofol might be age dependent, that is, a shorter time to peak effect in younger children. However, these analyses were potentially confounded by co‐administered drugs, in particular opioids and benzodiazepines. Thus, the goal of this prospective study was to characterize the influence of age and weight on the onset of hypnotic effects from propofol, reflected by the time to peak of propofol effect‐site concentration in the absence of additional drugs. Methods: A total of 46 healthy children aged 2–12 years presenting for elective surgery were included in our observational cohort study. Solely propofol was administered via a target‐controlled infusion pump programmed with the Paedfusor pharmacokinetic model. The BIS and infusion pump data were recorded. The effect of an induction "bolus" was recorded having stopped the pump once a propofol plasma target concentration of 7 μg.mL−1 was achieved. A direct‐response and an indirect‐response model in the context of nonlinear mixed‐effects modeling was used to characterize and compare BIS data in children aged 2–6 years and older children aged 8–12 years. Results: Time to peak of propofol effect‐site concentration had a difference (p‐value <.01) for age and weight, that is 84 [74, 96] (median [IQR] secs for children aged 2–6 years vs. 99 [91, 113] secs for children aged 8–12 years and 82 [71, 95] secs for weight 11–25 kg vs. 99 [91, 114] secs for weight 30–63 kg). The plasma effect‐site equilibration rate constant for propofol had a heterogeneous distribution with a median of 2.36 (IQR: 2.05–2.93; range: 0.83–7.31) per minute but showed a weight‐dependent effect in patients with weight below 45 kg. Conclusions: In children, the age and weight have an influence on time to peak effect of propofol. In the absence of opioids and benzodiazepines, time to peak effect was approximately 20% longer in children aged 8–12 years as compared to younger children. Such clinically relevant age and weight effects are an important consideration in the individualized titration of propofol dosing. [ABSTRACT FROM AUTHOR]

Ivermectin has been used since the 1980s as an anthelmintic and antiectoparasite agent worldwide. Currently, the only available oral formulation is tablets designed for adult patients. A patient‐friendly orodispersible tablet formulation designed for pediatric use (CHILD‐IVITAB) has been developed and is entering early phase clinical trials. To inform the pediatric program of CHILD‐IVITAB, 16 healthy adults were enrolled in a phase I, single‐center, open‐label, randomized, 2‐period, crossover, single‐dose trial which aimed to compare palatability, tolerability, and bioavailability and pharmacokinetics of CHILD‐IVITAB and their variability against the marketed ivermectin tablets (STROMECTOL) at a single dose of 12 mg in a fasting state. Palatability with CHILD‐IVITAB was considerably enhanced as compared to STROMECTOL. Both ivermectin formulations were well tolerated and safe. Relative bioavailability of CHILD‐IVITAB compared to STROMECTOL was estimated as the ratios of geometric means for Cmax, AUC 0‐∞, and AUC0‐last, which were 1.52 [90% CI: 1.13‐2.04], 1.27 [0.99‐1.62], and 1.29 [1.00‐1.66], respectively. Maximum drug concentrations occurred earlier with the CHILD‐IVITAB formulation, with a median Tmax at 3.0 h [range 2.0‐4.0 h] versus 4.0 h [range 2.0‐5.0 h] with STROMECTOL (P =.004). With CHILD‐IVITAB, variability in exposure was cut in half (coefficient of variation: 37% vs 70%) compared to STROMECTOL. Consistent with a more controlled absorption process, CHILD‐IVITAB was associated with reduced variability in drug exposure as compared to STROMECTOL. Together with a favorable palatability and tolerability profile, these findings motivate for further clinical studies to evaluate benefits of such a patient‐friendly ODT formulation in pediatric patients with a parasitic disease, including infants and young children <15 kg. [ABSTRACT FROM AUTHOR]

Serum creatinine in neonates follows complex dynamics due to maturation processes, most pronounced in the first few weeks of life. The development of a mechanism‐based model describing complex dynamics requires high expertise in pharmacometric (PMX) modeling and substantial model development time. A recently published machine learning (ML) approach of low‐dimensional neural ordinary differential equations (NODEs) is capable of modeling such data from newborns automatically. However, this efficient data‐driven approach in itself does not result in a clinically interpretable model. In this work, an approach to deriving an interpretable model with reasonable PMX‐type functions is presented. This "translation" was applied to derive a PMX model for serum creatinine in neonates considering maturation processes and covariates. The developed model was compared to a previously published mechanism‐based PMX model whereas both models had similar mechanistic structures. The developed model was then utilized to simulate serum creatinine concentrations in the first few weeks of life considering different covariate values for gestational age and birth weight. The reference serum creatinine values derived from these simulations are consistent with observed serum creatinine values and previously published reference values. Thus, the presented NODE‐based ML approach to model complex serum creatinine dynamics in newborns and derive interpretable, mathematical‐statistical components similar to those in a conventional PMX model demonstrates a novel, viable approach to facilitate the modeling of complex dynamics in clinical settings and pediatric drug development. [ABSTRACT FROM AUTHOR]

The antiparasitic drug ivermectin is approved for persons > 15 kg in the US and EU. A pharmacometric (PMX) population model with clinical PK data was developed (i) to characterize the effect of the patient-friendly ivermectin formulation CHILD-IVITAB on the absorption process and (ii) to evaluate dosing for studies in children < 15 kg. Simulations were performed to identify dosing with CHILD-IVITAB associated with similar exposure coverage in children ≥ 15 kg and < 15 kg as observed in adults receiving the reference formulation STROMECTOL®. A total of 448 ivermectin concentrations were available from 16 healthy adults. The absorption rate constant was 2.41 h−1 (CV 19%) for CHILD-IVITAB vs. 1.56 h−1 (CV 43%) for STROMECTOL®. Simulations indicated that 250 µg/kg of CHILD-IVITAB is associated with exposure coverage in children < 15 kg consistent with that observed in children ≥ 15 kg and adults receiving 200 µg/kg of STROMECTOL®. Performed analysis confirmed that CHILD-IVITAB is associated with faster and more controlled absorption than STROMECTOL®. Simulations indicate that 250 µg/kg of CHILD-IVITAB achieves equivalent ivermectin exposure coverage in children < 15 kg as seen in children ≥ 15 kg and adults. [ABSTRACT FROM AUTHOR]

The novel oral complement factor 5a receptor 1 antagonist ACT‐1014‐6470 was well tolerated in single‐ and multiple‐ascending dose studies, including 24 h Holter electrocardiogram (ECG) recordings evaluating its cardiodynamics based on data from single doses of 30–200 mg and twice‐daily (b.i.d.) dosing of 30–120 mg for 4.5 days. By‐time point, categorical, and morphological analyses as well as concentration‐QT modeling and simulations were performed. No relevant effect of ACT‐1014‐6470 on ECG parameters was observed in the categorical and morphological analyses. After single‐dose administration, the by‐time point analysis indicated a delayed dose‐dependent increase in placebo‐corrected change from baseline in QT interval corrected with Fridericia's formula (ΔΔQTcF) at >6 h postdose. After b.i.d. dosing, ΔΔQTcF remained elevated during the 24‐h recording period, suggesting that the effect was not directly related to ACT‐1014‐6470 plasma concentration. The concentration‐QT model described change from baseline in QTcF (ΔQTcF)‐time profiles best with a 1‐oscillator model of 24 h for circadian rhythm, an effect compartment, and a sigmoidal maximum effect model. Model‐predicted ΔΔQTcF was derived for lower doses and less‐frequent dosing than assessed clinically. Median and 90% prediction intervals of ΔΔQTcF for once‐daily doses of 30 mg and b.i.d. doses of 10 mg did not exceed the regulatory threshold of 10 ms but would achieve ACT‐1014‐6470 plasma concentrations enabling adequate target engagement. Results from cardiodynamic assessments identified dose levels and dosing regimens that could be considered for future clinical trials, attempting to reduce QT liability. [ABSTRACT FROM AUTHOR]