Development of Novel Tamsulosin Pellet-Loaded Oral Disintegrating Tablet Bioequivalent to Commercial Capsule in Beagle Dogs Using Microcrystalline Cellulose and Mannitol

In this study, we developed a tamsulosin pellet-loaded orally disintegrating tablet (ODT) that is bioequivalent to commercially available products and has improved patient compliance using microcrystalline cellulose (MCC) and mannitol. Utilizing the fluid bed technique, the drug, sustained release (SR) layer, and enteric layer were sequentially prepared by coating MCC pellets with the drug, HPMC, Kollicoat, and a mixture of Eudragit L and Eudragit NE, respectively, resulting in the production of tamsulosin pellets. The tamsulosin pellet, composed of the MCC pellet, drug layer, SR layer, and enteric layer at a weight ratio of 20:0.8:4.95:6.41, was selected because its dissolution was equivalent to that of the commercial capsule. Tamsulosin pellet-loaded ODTs were prepared using tamsulosin pellets and various co-processed excipients. The tamsulosin pellet-loaded ODT composed of tamsulosin pellets, mannitol-MCC mixture, silicon dioxide, and magnesium stearate at a weight ratio of 32.16:161.84:4.0:2.0 gave the best protective effect on the coating process and a dissolution profile similar to that of the commercial capsule. Finally, no significant differences in beagle dogs were observed in pharmacokinetic parameters, suggesting that they were bioequivalent. In conclusion, tamsulosin pellet-loaded ODTs could be a potential alternative to commercial capsules, improving patient compliance.

Relative Bioavailability of Fixed-Dose Combinations of Tamsulosin and Dutasteride: Results From 2 Randomized Trials in Healthy Male Volunteers

The relative bioavailabilities of dutasteride/tamsulosin hydrochloride 0.5 mg/0.2 mg fixed-dose combination (FDC) capsules compared with coadministered reference products (1 dutasteride 0.5-mg capsule [Avodart^® ] + 1 tamsulosin hydrochloride 0.2-mg orally disintegrating tablet [Harnal D^® ]) were investigated in 2 clinical trials under fasted and fed conditions (ClinicalTrials.gov NCT02184585 and NCT02509104). Both trials were open-label, randomized, single-dose, crossover studies in healthy male adults aged 18-65 years. Trial 1 evaluated 2 formulations (FDC1 and FDC2), and trial 2 evaluated a third formulation (FDC3). The primary end points were dutasteride area under the concentration-time curve from time 0 to t (AUC_(0-t) ) and peak plasma concentration (C_max ) and tamsulosin AUC_(0-∞) , AUC_(0-t) , and C_max . The formulations were considered to be bioequivalent if the 90%CIs for the geometric mean ratios for each end point were within the range of 0.80-1.25. For FDC1 in trial 1, bioequivalence criteria were not met for dutasteride C_max or AUC in the fasted state or for tamsulosin C_max in the fasted or fed states. For FDC2 in trial 1, all bioequivalence criteria were met except for tamsulosin C_max in the fasted state. For FDC3 in trial 2, bioequivalence criteria were met for all dutasteride and tamsulosin end points in both the fed and fasted states. Safety profiles were similar for all FDC formulations and combination treatments.

Pharmacokinetic interaction of finasteride with tamsulosin hydrochloride: an open-label, randomized, 3-period crossover study in healthy Chinese male volunteers

PURPOSE

The primary aim of this study was to evaluate whether there was clinically significant pharmacokinetic (PK) interaction between finasteride and tamsulosin in healthy Chinese male subjects.

METHODS

This was an open-label, randomized, 3-period, crossover study. Subjects received single and multiple doses of 5 mg finasteride alone, single and multiple doses of 0.2 mg tamsulosin hydrochloride sustained-release capsule alone, and single and multiple doses of 5 mg finasteride with 0.2 mg tamsulosin hydrochloride, in an order determined by a computerized randomization schedule. Blood samples were collected up to 48 hours after dosing on study day 1 and up to 24 hours after dosing on study day 9 for determination of plasma concentrations with a validated LC-MS/MS method. Pharmacokinetic parameters were estimated via noncompartmental methods. Tolerability was evaluated by monitoring adverse events, laboratory assays, vital signs, and 12-lead ECG.

FINDINGS

Fifteen subjects were enrolled, and 14 completed the study. The geometric mean ratios (GMRs) (90% CIs) of AUC(τ,ss) and C(max,ss) values of finasteride at steady state between coadministration of finasteride and tamsulosin hydrochloride and finasteride alone were 1.14 (1.05-1.23) and 1.06 (0.99-1.14), respectively. The GMRs (90% CIs) for AUC(0-t) and C(max) values of finasteride for a single dose of coadministration of finasteride and tamsulosin hydrochloride and finasteride alone were 1.02 (0.94-1.11) and 1.06 (1.01-1.11), respectively. The GMRs (90% CIs) for AUC(τ,ss) and C(max,ss) values of tamsulosin at steady-state for coadministration of finasteride and tamsulosin hydrochloride and tamsulosin hydrochloride alone were 1.18 (1.05-1.33) and 1.23 (1.06-1.43), respectively. The GMRs (90% CIs) for AUC(0-t) and C(max) values of tamsulosin for a single dose of coadministration of finasteride and tamsulosin hydrochloride and tamsulosin hydrochloride alone were 1.04 (0.97-1.10) and 1.04 (0.98-1.11), respectively. Statistical analyses confirmed that the 90% CIs for these PK parameters were within the predefined not clinically significant PK drug-drug interaction effect boundaries (0.5-2.0) in this study. If comparing the findings with narrower boundaries (0.8-1.25), the conclusion may not be supportive for tamsulosin hydrochloride. During the study, a total of 4 adverse events were reported in 3 subjects including allergic reaction, abnormal findings on an ECG, a slight increase in alanine aminotransferase, and a positive result on glucose urine test.

IMPLICATIONS

Both finasteride and tamsulosin hydrochloride were well tolerated. Coadministration of finasteride and tamulosin hydrochloride seems unlikely to lead to a clinically significant PK drug-drug interaction, after a single dose and at steady state.