A composition comprising: (a) a spray dried solid amorphous dispersion comprising a low-solubility drug and a concentration-enhancing polymer, selected from the group consisting of hydroxypropyl methyl cellulose acetate succinate, hydroxypropyl methyl cellulose phthalate, cellulose acetate phthalate, cellulose acetate trimellitate, carboxymethyl ethyl cellulose, hydroxypropyl methyl cellulose, poloxamers, polyvinylpyrrolidone, polyvinyl alcohols that have at least a portion of their repeat units in hydrolyzed form, and mixtures thereof; (b) a lipophilic microphase-forming material, said composition having a mass ratio of said lipophilic microphase-forming material to said low solubility drug of from 0.1 to 100; (c) said lipophilic microphase-forming material being present in a sufficient amount so that said composition provides concentration enhancement of said drug in a use environment at least 1.25-fold relative to both a first control composition and a second control composition; wherein (i) said first control composition consists essentially of an equivalent amount of said solid amorphous dispersion with no lipophilic microphase-forming material present; (ii) said second control composition consists essentially of an equivalent amount of said low-solubility drug in undispersed form with an equivalent amount of said lipophilic, microphase-forming material but with no concentration-enhancing polymer; wherein said solid amorphous dispersion and said lipophilic microphase-forming material are both present in a single dosage form which is an oral tablet or capsule; wherein said lipophilic microphase-forming material is selected from the group consisting of sulfonated hydrocarbons and their salts, poloxamers, polyoxyethylene alkyl ethers, polyoxyethylene sorbitan fatty acid esters, short-chain glyceryl mono-alkylates, polyglycolized glycerides, mono- and di-alkylate esters of polyols, polyoxyethylene 20 sorbitan monooleate, polyoxyethylene 20 sorbitan monolaurate, polyethylene (40 or 60) hydrogenated castor oil, polyoxyethylene castor oil, polyethylene hydrogenated castor oil, alpha tocopheryl polyethylene glycol 1000 succinate, glyceryl PEG 8 caprylate/caprate, PEG 32 glyceryl laurate, polyoxyethylene fatty acid esters, and polyoxyethylene fatty acid ethers, and mixtures thereof. (a) a spray dried solid amorphous dispersion comprising a low-solubility drug and a concentration-enhancing polymer, selected from the group consisting of hydroxypropyl methyl cellulose acetate succinate, hydroxypropyl methyl cellulose phthalate, cellulose acetate phthalate, cellulose acetate trimellitate, carboxymethyl ethyl cellulose, hydroxypropyl methyl cellulose, poloxamers, polyvinylpyrrolidone, polyvinyl alcohols that have at least a portion of their repeat units in hydrolyzed form, and mixtures thereof; (b) a lipophilic microphase-forming material, said composition having a mass ratio of said lipophilic microphase-forming material to said low solubility drug of from 0.1 to 100; (c) said lipophilic microphase-forming material being present in a sufficient amount so that said composition provides concentration enhancement of said drug in a use environment at least 1.25-fold relative to both a first control composition and a second control composition; wherein (i) said first control composition consists essentially of an equivalent amount of said solid amorphous dispersion with no lipophilic microphase-forming material present; (ii) said second control composition consists essentially of an equivalent amount of said low-solubility drug in undispersed form with an equivalent amount of said lipophilic, microphase-forming material but with no concentration-enhancing polymer; (i) said first control composition consists essentially of an equivalent amount of said solid amorphous dispersion with no lipophilic microphase-forming material present; (ii) said second control composition consists essentially of an equivalent amount of said low-solubility drug in undispersed form with an equivalent amount of said lipophilic, microphase-forming material but with no concentration-enhancing polymer;