THE PRESENT INVENTION RELATES TO A PHARMACEUTICAL FORMULATION COMPRISING THE DRUG 4-[3-(4- CYCLOPROPANECARBONYL-PIPERAZINE- 1 -CARBONYL)-4-FLUORO-BENZYL] -2H-PHTHALAZI N-1 -ONE IN A SOLID DISPERSION WITH A MATRIX POLYMER THAT EXHIBITS LOW HYGROSCOPICITY AND HIGH SOFTENING TEMPERATURE, SUCH AS COPOVIDONE. THE INVENTION ALSO RELATES TO A DAILY PHARMACEUTICAL DOSE OF THE DRUG PROVIDED BY SUCH A FORMULATION. IN ADDITION, THE INVENTION RELATES TO THE USE OF A MATRIX POLYMER THAT EXHIBITS LOW HYGROSCOPICITY AND HIGH SOFTENING TEMPERATURE IN SOLID DISPERSION WITH 4-[3-(4-CYCLOPROPANECARBORIYL-PIPERAZINE- 1 -CARBONYL)-4-FLUORO-BENZYL]-2H- PHTHALAZIN-1 -ONE FOR INCREASING THE BIOAVAILABILITY OF THE DRUG.