An amorphous solid dispersion comprises 6-(1-acryloylpiperidin-4-yl)-2-(4-phenoxyphenyl) nicotinamide (Compound I) or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable polymer. Also provided is pharmaceutical compositions comprising the amorphous solid dispersion, which is stable upon storage and provides a better dissolution rate and bioavailability when comparing with a crystalline form.本發明涉及含有6-(丙烯醯基呱啶-4-基)-2-(4-苯氧基苯基)尼克醯胺(化合物I)或其可藥用的鹽和一種可藥用的聚合物的固體分散體。本發明還涉及含有該固體分散體的藥物組合物。本發明的固體分散體存放穩定,比晶型具有更好的溶出和生物利用度。