An injection-molded shell of a dosage form of good quality is producible by a) providing a composition comprising i) from 25 to 90 weight percent of ethylcellulose, ii) from 7.5 to 60 weight percent of a polysaccharide or polysaccharide derivative being different from ethylcellulose, and iii) from 2.5 to 50 weight percent of at least one component being different from polysaccharides and polysaccharide derivatives, based on the total weight of the composition, with the proviso that the composition comprises zero or not more than 10 weight percent of gelatin and zero or not more than 10 weight percent of a polymer comprising homo- or copolymerized acrylic acid, homo- or copolymerized methacrylic acid, a homo- or copolymerized acrylate or a homo- or copolymerized methacrylate, and b) subjecting the composition to shearing and heat to plasticize the composition and injection-molding the plasticized composition into a three-dimensional shell of a dosage form.