Pharmacokinetic Analysis of Intraocular Penetration of Latanoprost Solutions with Different Preservatives in Human Eyes.

PURPOSE: To investigate the effect of excipients on latanoprost penetration into the aqueous humor with clinically available 6 products with different solutions mainly in the types and concentrations of preservatives. METHODS: In 363 patients with cataracts, we instilled 1 latanoprost drop in 1 eye before surgery. The drop was randomly selected by brand name product (A) and 5 generic products (B-F) composed with different excipients. B contains similar excipients to A. C and D contain lower concentrations of benzalkonium chloride than A. E includes sodium benzoate, and F contains no preservatives. At 0.5-1, 3, and 6 h after instillation, samples of aqueous humor were collected to determine the latanoprost free acid by mass spectrometry. The time course of intraocular concentration and the areas under the aqueous humor latanoprost free acid concentration-time curves (AUCs) were calculated. RESULTS: At 0.5-1 h, the aqueous humor concentration of latanoprost free acid was 8.5 ± 1.0 ng/mL for C, which was significantly higher (P < 0.01) than that of A (3.4 ± 0.5 ng/mL). At 3 and 6 h, however, no significant difference was noted in the concentrations of latanoprost free acid between the brand name and generic products. For each of the generic products, the peak free acid concentration was above the known threshold concentration for biological activity. At 6 h postdose, however, the levels of latanoprost free acid were below the threshold for Products C, E, and F. Comparisons of AUC0-6h and AUC0-24h values showed that these parameters were the greatest with A, and E was significantly inferior to A (P < 0.05). CONCLUSIONS: Currently available latanoprost solutions with different preservatives showed sufficient intraocular concentration to activate the FP receptor, but different pharmacokinetic profiles of absorption or elimination.

Randomized controlled study comparing two doses of intravenous granisetron (1 and 3 mg) for acute chemotherapy-induced nausea and vomiting in cancer patients: a non-inferiority trial.

OBJECTIVE: The aim of this study was to assess the non-inferiority of 1 mg to 3 mg granisetron (GRN) injection for the treatment of acute chemotherapy-induced nausea and vomiting (CINV) and to evaluate the tolerability of GRN given at 1 mg in Japanese cancer patients. METHODS: Patients with cancer receiving highly emetogenic chemotherapy were enrolled in this single-blind randomized controlled study. Patients were randomly assigned to receive GRN at a single dose of 1 or 3 mg. The primary endpoint was the rate of complete protection from emetic events (no vomiting, no retching and no need for rescue medication) during the first 24 h following the initiation of chemotherapy. RESULTS: There were 89 patients in the 1 mg group and 90 patients in the 3 mg group. Complete protection was achieved in 70 patients (78.7%) in the 1 mg group and 73 (81.1%) patients in the 3 mg group. The one-sided test did not reveal non-inferiority of either dose of GRN to the other at a 5% significance level. CONCLUSIONS: Our data failed to show the non-inferiority of 1 mg of GRN to 3 mg of GRN administered as a single dose. However, the rate of complete protection from nausea and vomiting was similar in the two groups. Given the recommended dosage in the guidelines and the economic need for reduction of medical care expenses in Japan, prophylactic administration of GRN at 1 mg may be an appropriate, alternative treatment for acute CINV in cancer patients.