Comparison of pharmacokinetic characteristics of sildenafil citrate chewable tablets and film-coated tablets in healthy male subjects

Abstract

UI14SDF100CW is a chewable tablet of sildenafil citrate, which was developed to improve compliance through convenience of administration. The purpose of this study was to compare the pharmacokinetic (PK) properties of sildenafil citrate chewable tablets (UI14SDF100CW) and conventional sildenafil citrate film-coated tablets (Viagra®, Pfizer). A randomized, open-label, single dose, two-treatment, two-period, two-way crossover study was conducted in 60 healthy male volunteers. In each period, the subjects received a single oral dose of UI14SDF100CW or Viagra® (both tablets contain 140.45 mg of sildenafil citrate, which is equivalent to 100 mg of sildenafil). Serial blood samples were collected up to 24 h post-dose for PK analysis. The plasma concentration of sildenafil was determined using a validated HPLC-MS/MS assay. PK parameters of sildenafil were calculated using non-compartmental methods. The plasma concentration-time profiles of sildenafil in both formulations were similar. For UI14SDF100CW, the C max and AUC last of sildenafil were 1068.69 ± 458.25 (mean ± standard deviation) mg/L and 3580.59 ± 1680.29 h·mg/L, and the corresponding values for Viagra® were 1146.84 ± 501.70 mg/L and 3406.35 ± 1452.31 h·mg/L, respectively. The geometric mean ratios (90% confidence intervals) of UI14SDF100CW to Viagra® for C max and AUC last were 0.933 (0.853-1.021) and 1.034 (0.969-1.108), respectively, which met the bioequivalence criteria of Korean regulatory agency. In conclusion, UI14SDF100CW and Viagra® showed similar PK properties. Therefore, UI14SDF100CW can be an alternative to sildenafil for the treatment of erectile dysfunction, providing better compliance.

Sildenafil 4.0—Integrated Synthetic Chemistry, Formulation and Analytical Strategies Effecting Immense Therapeutic and Societal Impact in the Fourth Industrial Era

“…Statistically important reduction in absorption rate is observed whereas sildenafil is co-administered with high fat meal (delayed t max by 1 h in fed state compared to 30–120 min t max in fasted state, 90% confidence intervals CI: 0.7 ± 1.5 using ANOVA appropriate design) as well as in mean C max (−29% in fed state, 90% CI: 19 ± 38) [ 60 ]. The combination of food effects with the diminished bioavailability due to extensive first path metabolism [ 60 ], has led contemporary researchers to focus on upgrading the existing oral dosage formulations [ 96 , 97 , 98 , 99 , 100 ] and even apply alternative routes of administration i.e., intranasal, transdermal and intravenously [ 101 , 102 , 103 ].…”

“…In order to avoid the disadvantages of the film-coated tablet i.e., poor patient compliance owing to swallowing difficulties Yoo et al prepared chewable sildenafil tablets. In detail, C max and AUC last geometric mean ratios for 90% CI, indicated bioequivalence between the chewable sildenafil tablet 0.933 (0.853–1.021) and the marketed one 1.034 (0.964–1.108), within the Korean bioequivalence criterion of 0.80 to 1.25 [ 99 ]. The clinical study was conducted in 60 healthy male volunteers and concluded that the chewable tablet showed similar pharmacokinetic properties to the market product and therefore can be an alternative to sildenafil for the treatment of erectile dysfunction, providing better compliance [ 99 ].…”