The present invention provides a novel polymorph of the hemisuccinate salt of 2,4,6-trifluoro-N-[6-(1-methyl-piperidine-4-carbonyl)-pyridin-2-yl]-benzamide (Form A) characterized by a unique X-ray diffraction pattern and Differential Scanning Calorimetry profile, as well as a unique crystalline structure. This polymorph is useful in pharmaceutical compositions, for example, for the treatment and prevention of migraine. The invention also provides a process for the synthesis of pyridinoylpiperidine compounds of Formula I in high yield and high purity. In particular, the provides a process for the preparation of 2,4,6-trifluoro-N-[6-(1-methyl-piperidine-4-carbonyl)-pyridin-2-yl]-benzamide, its hemisuccinate salt and polymorph (Form A).