Study of the Safety and Pharmacokinetics of Dexamethasone Cipecilate (NS-126C), a Steroid Nasal Spray-Phase I Clinical Study in the Elderly and at a High Dose-

In a placebo-controlled double-blind phase I clinical study to determine safety and pharmacokinetics, dexamethasone cipecilate (NS-126C) was administered at 400 μg once a day to healthy elderly subjects 65 years or older or at 800 μg once a day to healthy nonelderly subjects for 14 days. Analysis results of subjective symptoms, objective findings, anterior rhinoscopy, laboratory tests, adrenal function tests, physical examination, nasal fungal tests, and nasal ciliary function tests showed no adverse events in the elderly or study drug-related adverse events in the nonelderly. No adrenal function effect was observed. Pharmacokinetic examination showed that plasma levels of the unchanged drug and its principal metabolite DX-17-CPC were less than the quantitation limit (<16 pg/ml) in all elderly subjects. In nonelderly subjects, these were detected in 3 of 6 subjects but at levels below 3 times the quantitation limit. These findings confirmed NS-126C safety at 400 μg once a day in the elderly and at 800 μg once a day in the nonelderly for 14 days, together with extremely low systemic exposure.