P. Minghetti et al., BUCCOADHESIVE SLOW-RELEASE TABLETS OF ACITRETIN - DESIGN AND IN-VIVO EVALUATION, International journal of pharmaceutics, 169(2), 1998, pp. 195-202
Acitretin is an aromatic retinoid used in the treatment of buccal kera
tinization disorders. The local therapy has recently shown promising r
esults. The aims of this study were to develop buccoadhesive tablets w
ith different 'in vitro' release profiles of acitretin in order to sel
ect the types of tablets to be tested 'in vive', to determine the sali
va acitretin concentration and to verify the therapeutical efficacy. O
n the basis of preliminary in vivo studies the dose of 10 mg of acitre
tin was used. Ten different formulations of two-layer buccoadhesive ta
blets were considered. The inferior layer (10 mg of Carbopol(R) 934P:M
ethocel(R) K4M, 1:2) provided bioadhesive properties to all the tablet
s. The upper layer of all tablets was the slow-release matrix containi
ng the acitretin. The release-controlling component was an hydroxyprop
ylmethylcellulose (HPMC); lactose was used as soluble filler. Aiming t
o achieve a wide range of release rates, three types of HPMC with diff
erent viscosity grades were used. A good relation was found between th
e in vitro dissolution profile and the in vivo permanence of acitretin
in the oral cavity, that was longer for the formulation containing 85
% of Methocel(R) E5 than the formulation containing 45% of Methocel(R)
E5. Both formulations permitted to obtain good clinical results. (C)
1998 Elsevier Science B.V. All rights reserved.