Long-Term Safety and Effectiveness of Diquafosol for the Treatment of Dry Eye in a Real-World Setting: A Prospective Observational Study.

INTRODUCTION: Diquafosol is a P2Y2 receptor agonist that has been shown to be effective in the treatment of dry eye disease (DED) in short-term studies; however, its long-term safety and effectiveness have not been evaluated in a real-world setting. METHODS: This prospective, multicentre, open-label observational study was conducted in patients with DED over 12 months. Safety endpoints included the incidence of adverse drug reactions (ADRs) and serious ADRs. Effectiveness endpoints included change from baseline in keratoconjunctival staining score, tear film break-up time (BUT) and Dry Eye-related Quality of Life Score (DEQS). RESULTS: A total of 580 patients were included, most of whom were female (82.9%). The proportion of patients who completed 12 months of observation was 55.0%, the most common reason for discontinuation was patient decision (54.6%). The incidence of ADRs was 10.7% and was highest during the first month of treatment (5.5%); no serious ADRs were reported. Compared with baseline, significant improvements in all effectiveness outcomes, including keratoconjunctival fluorescein staining score, BUT and DEQS summary score, were observed at each evaluation during the treatment period (p < 0.001). CONCLUSION: The present, real-world study showed that diquafosol 3.0% ophthalmic solution was well tolerated and effective in the long-term treatment of DED.

Gene disruption of ribosomal protein L5 (RPL5) decreased the sensitivity of CHO-K1 cells to uncoupler carbonylcyanide-3-chlorophenylhydrazone.

Protonophoric uncoupler carbonylcyanide-3-chlorophenylhydrazone (CCCP) decreases the proton motive force (ΔP) of the mitochondrial inner membrane and results in inhibition of oxidative phosphorylation. In this study, a CCCP-resistant clone was isolated from a random gene trap insertional mutant library of Chinese hamster ovary (CHO)-K1 cells which was constructed by infecting a retrovirus vector, ROSAßgeo. Although we expected the isolation of the mutants defective in nuclear genes responsible for mitochondrial functions, the disrupted gene of the isolated mutant that we named R1 cells was identified as one of the alleles for ribosomal protein 5 of large subunit (RPL5). The R1 cells express as much as 80% RPL5 protein compared with the parental CHO-K1 cells, possibly due to enhanced transcription from a remaining wild-type RPL5 allele in R1 cells. Furthermore, the protein amount is not decreased by CCCP in R1 cells, in contrast to its clear reduction by CCCP in parental cells. Since mutations of RPL5 and other ribosomal proteins are responsible for the ribosomopathies and cancer, the present mutant may be a useful cellular model of such human diseases from a viewpoint of energy metabolism as well as a tool for the study of ribosome biogenesis and extra-ribosomal function of the RPL5 protein.

Dose-response relationships of rabeprazole 5, 10, 20, and 40 mg once daily on suppression of gastric acid secretion through the night in healthy Japanese individuals with different CYP2C19 genotypes.

PURPOSE: This study was designed to investigate the antisecretory activity of rabeprazole administered once daily in doses of 5, 10, 20, and 40 mg and different cytochrome P450 2C19 (CYP2C19) genotypes on gastric pH in healthy individuals. Additional objectives were delineating the nighttime from the daytime effect and determining the relationships between the pharmacokinetics and pharmacodynamics of rabeprazole. METHODS: Eight individuals of each of the three genotypes of CYP2C19-homozygous extensive metabolizers (homo-EMs), heterozygous EMs (hetero-EMs), and poor metabolizers (PMs)-were recruited. Twenty-four individuals received a once-daily dose, with dosing interval 24 h of 5, 10, 20, or 40 mg rabeprazole for 5 days in a 4-period crossover fashion. Twenty-four-hour intragastric pH and plasma rabeprazole concentrations were determined on day 5. RESULTS: A dose-dependent increase in median pH and in pH 4 holding time was observed across all CYP2C19 genotypes. When rabeprazole was increased from 20 mg to 40 mg, the differences and 95% confidence intervals (CIs) of nighttime pH 4 holding time between 40 mg and 20 mg in homo-EMs, hetero-EMs, and PMs were 8.0% (-5.0% -21.0%), 28.7% (15.7% -41.6%), and 16.9% (3.9% -29.9%), respectively. The relationship between the area under the plasma concentration-time curve up to the last time point at which rabeprazole was quantifiable (AUC(0-t)) and the pH 4 holding time could be described using a sigmoid maximum effect (E(max)) model. CONCLUSIONS: Our data demonstrate that increasing rabeprazole dose up to 40 mg once daily results in an increasing pharmacodynamic effect, which is most apparent for the control of nocturnal gastric acid secretion.