Pharmaceutical formulation comprising cibenzoline or salt thereof

A pharmaceutical formulation comprising from 150 mg to 450 mg of S(−)-cibenzoline or a pharmaceutically acceptable salt thereof;

• wherein the pharmaceutical formulation includes an immediate release layer and an extended release layer;
• wherein a weight ratio of the S(−)-cibenzoline or the pharmaceutically acceptable salt thereof contained in the immediate release layer relative to the S(−)-cibenzoline or the pharmaceutically acceptable salt thereof contained in the extended release layer is from 1:4 to 1:1;
• and
• wherein the pharmaceutical formulation satisfies following biphasic dissolution profile in a dissolution test:
• 1) 30 to 50% of the total weight of the S(−)-cibenzoline or the pharmaceutically acceptable salt thereof is released within 30 minutes, and
• 2) thereafter, 90% or more of the total weight of the S(−)-cibenzoline or the pharmaceutically acceptable salt thereof is released within 12 hours.