Disclosed is an oral pharmaceutical composition, comprising bendamustine (also known as 4-[5-[Bis(2-chloroethyl)amino]-1-methylbenzimidazol-2-yl]butanoic acid) or a pharmaceutically acceptable, ester, salt or solvate thereof as an active ingredient, and a pharmaceutically acceptable excipient, which is a pharmaceutically acceptable non-ionic hydrophilic surfactant. Examples of non-ionic hydrophilic surfactant are propylene glycol dicaprylocaprate, propyleneglycol monolaurate, linoleoyl macrogol glycerides, oleoyl macrogolglycerides, diethyleneglycol monobutylether, diethyleneglycol monoethylether, propyleneglycol caprylate, diethyleneglycolmonomethylether, polysorbate 20, macrogol glyceryl cocoates, poloxamer 105, poloxamer 184, polysorbate 40, macrogol 15 hydroxy stearate and macrogol 23 lauryl ether.
