A solid composition comprising sofosbuvir and at least one pharmaceutically acceptable matrix compound wherein at least 99 weight % of the sofosbuvir comprised in the composition are present in amorphous form at least 99 weight % of the solid composition consist of the sofosbuvir and the at least one matrix compound and wherein the solid composition contains the sofosbuvir in an amount of at least 55 weight % based on the combined weight of the sofosbuvir and the at least one matrix compound.