Ocular Administration of Palonosetron in the Prevention of Cisplatin-Induced Nausea and Vomiting.

Cancer treatments are frequently associated with nausea and vomiting despite greatly improved preventive medication. Administration of antinausea agents as eye drops might provide easy and rapid access to the systemic circulation for prevention of nausea and vomiting and for the treatment of breakthrough nausea, but the ocular administration route has rarely been evaluated. Palonosetron is a second-generation 5-hydroxytryptamine 3 receptor antagonist approved for prevention and treatment of chemotherapy-induced nausea and vomiting. We compared ocular administration of palonosetron to non-active vehicle eye drops and to intravenous palonosetron in the prevention of cisplatin-induced nausea and vomiting in beagle dogs. Palonosetron ocular drops at the dose of 30 µg/kg reduced cumulative nausea over time as measured with the area under the visual analog scale curve by 98% compared with the vehicle and reduced nausea-associated dog behavior by 95%. Vomiting was completely prevented with repeated palonosetron ocular dosing. Hydroxypropyl-ß-cyclodextrin (HP-ß-CD) palonosetron formulation was well tolerated locally at the palonosetron concentration of 3 mg/ml. Absorption of palonosetron from eye drops was fast. Ten minutes after ocular administration, palonosetron plasma concentrations were similar compared with intravenous administration, and remained similar for six hours. We conclude that palonosetron is rapidly absorbed into the systemic circulation from eye drops. Ocularly administered palonosetron was well tolerated in the HP-ß-CD formulation and was highly effective in the prevention of cisplatin-induced nausea and vomiting. Evaluation of the safety and efficacy of ocular administration of palonosetron is warranted in the prevention and treatment of chemotherapy-induced nausea and vomiting in clinical trials. SIGNIFICANCE STATEMENT: Palonosetron, an effective and well-tolerated antiemetic drug was rapidly absorbed into the systemic blood circulation when administered as eye drops. The achieved palonosetron blood concentrations prevented cisplatin-induced nausea and vomiting in beagle dogs. Palonosetron eye drops might provide an easy and quick method for administering palonosetron when parenteral administration is desired and intravenous administration is not feasible.

Results from a Joined Prospective Study to Evaluate the Sensitivity of the In Vivo Dog QT Assay in Line with the ICH E14/S7B Q&A Best Practices.

The ICH E14/S7B Q&As highlighted the need for best practices concerning the design, execution, analysis, interpretation, and reporting of the in vivo non-rodent QT assay as a component of the integrated risk assessment to potentially support a TQT waiver or substitute. We conducted a dog telemetry study to assess the effects on QTc of six reference compounds (five positive and one negative) previously evaluated by Darpo et al. (2015) in humans. The sensitivity of the assay to detect QTc increases was determined, and exposure-response analysis was performed, as done in clinical practice. By-timepoint analysis showed QTc prolongation induced by moxifloxacin, dofetilide, dolasetron, ondansetron, and quinine within human relevant plasma exposures ranges. Moreover, a hysteresis was observed for quinine. As expected, levocetirizine showed no statistically significant effect on QTc across a range of exposure, well exceeding the therapeutic Cmax. Power analyses confirmed the study ability to detect statistically significant QTc changes of less than 10 milliseconds with 80% probability, even with a sample size as low as n = 4 animals. Finally, concentration-QTc modeling enabled to predict the minimal plasma concentration needed to detect a 10 milliseconds QTc prolongation, including for quinine. The comparison with clinical available data supported the relevance of dogs under these experimental conditions as a robust translational predictor of drug-induced QTc prolongation in humans as a key pillar of the integrated risk assessment.

Evaluation of neurotoxicity potential in rats: the functional observational battery.

This unit describes the functional observational battery (FOB), a behavioral screening procedure commonly used in safety pharmacology and toxicology studies to assess potentially adverse effects of test agents on the central nervous system. The battery includes general observations and the determination of reactivity to various stimuli. Also presented is the severity score index for analyzing individual measurements and evaluations over a range of endpoints. The severity score index can be used to identify, quantify, and describe the effects of compounds on neurological, autonomic, and behavioral functions.