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Introduction: Docetaxel, a taxane used in the treatment of solid tumours, exerts pharmacological activity when in its unbound form. We report a sensitive assay to quantify unbound docetaxel after oral administration of docetaxel plus encequidar (oDox+E). Unbound drug quantification is important due to its direct correlation with drug-related toxicity and therapeutic efficacy. We improve on the sensitivity of current assay methods and demonstrate the utility of the assay on a novel formulation of oral docetaxel. Methods: Ultrafiltration followed by high-performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS) was utilized. Long-term stability, precision, accuracy, and recovery experiments were conducted to validate the assay. Additionally, patient samples from a Phase I dose-escalation pharmacokinetic study were analyzed using the developed assay. Results: The assay method exhibited long-term stability with an observed change between 0.8 and 6.9% after 131 days of storage at −60 °C. Precision and accuracy quality controls met the FDA acceptance criteria. An average recovery of 88% was obtained. Patient sample analysis demonstrated successful implementation of the assay. Conclusion: A validated sensitive assay was developed with an LLOQ of 0.084 ng/mL using 485 µL of human plasma. The sensitivity of the assay allowed quantification of unbound docetaxel concentrations in an early-phase oDox+E clinical study to compare it against IV docetaxel using pharmacokinetic modelling. Successful development of oDox+E represents an opportunity to replace the current IV docetaxel regimen with an oral regimen with lower cost, decreased side effects, and improve patient quality of life and experience. [ABSTRACT FROM AUTHOR]

Objective  This study was aimed to determine mydriatic regimen(s) used in neonatal units in Aotearoa, New Zealand (NZ), and Australia and to estimate the frequency of adverse drug events following mydriatic administration in preterm neonates. Study Design  A cross-sectional survey was sent to neonatal nursing staff listed in the Australian and New Zealand Neonatal Network contact list. Participants were asked to state what mydriatic regimen they use, and to estimate the frequency of adverse drug events when eye drops were administered for retinopathy of prematurity eye examinations (ROPEE). Results  Thirteen different mydriatic regimens were identified; phenylephrine 2.5% and cyclopentolate 0.5% (1 standard drop of each) was the most commonly used regimen. Two of the regimens exceeded adult doses and five regimens included a mydriatic that is equivalent to an adult dose. Following mydriatic instillation, the three most common adverse effects were apnea, tachycardia, and periorbital pallor. Conclusion  Low-concentration single-microdrop regimens are currently in use and resulting in successful ROPEE, yet doses exceeding adult doses are in use throughout Aotearoa, NZ, and Australian units. We know from this dataset that neonates are experiencing unwanted and potentially preventable, adverse effects associated with mydriatics, and every effort should be made to minimize this risk. Key Points Thirteen different regimens are in use in Aotearoa, NZ, and Australia. Three regimens use doses in excess of adult doses. Phenylephrine 2.5% and cyclopentolate 0.5% (one standard drop of each) is the most common regimen [ABSTRACT FROM AUTHOR]