A stable complex with improved physicochemical characteristics and enhanced biological performance comprising a) as active compound Abiraterone acetate; or a combination of active compounds including Abiraterone acetate; b) at least one complexing agent chosen from polyethylene glycol glycerides composed of mono-, di- and triglycerides and mono- and diesters of polyethylene glycol, hydroxypropylcellulose, poloxamers, vinylpyrrolidone/vinyl acetate copolymer, polyethylene glycol, poly(2-ethyl-2-oxazoline), polyvinylpyrrolidone, block copolymers based on ethylene oxide and propylene oxide, poly(maleic acid/methyl vinyl ether), polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer, polyoxyl 15 hydroxystearate, polyvinyl alcohol-polyethylene glycol graft copolymer and d-alpha tocopheryl polyethylene glycol 1000 succinate; c) sodium deoxycholate as pharmaceutically acceptable excipient; wherein said complex consists of spherical particles, and wherein said complex has a particle size, which is less than 600 nm, and possesses the following features: - it is instantaneously redispersible in physiological relevant media; - it has increased dissolution rate; - it is stable in solid form and in colloid solution and/or dispersion; - its apparent solubility in water is of at least 0.6 mg/mL; - it shows X-ray amorphous character in the solid form; - it has a PAMPA permeability of at least 0.5*10 -6 cm/s when dispersed in distilled water, which does not decrease in time at least for 3 months; - exhibits no positive food effect which allows significant dose reduction and the abandoning of the requirement of taking the drug on an empty stomach; - the variability of exposure is significantly reduced when compared to Zytiga. a) as active compound Abiraterone acetate; or a combination of active compounds including Abiraterone acetate; b) at least one complexing agent chosen from polyethylene glycol glycerides composed of mono-, di- and triglycerides and mono- and diesters of polyethylene glycol, hydroxypropylcellulose, poloxamers, vinylpyrrolidone/vinyl acetate copolymer, polyethylene glycol, poly(2-ethyl-2-oxazoline), polyvinylpyrrolidone, block copolymers based on ethylene oxide and propylene oxide, poly(maleic acid/methyl vinyl ether), polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer, polyoxyl 15 hydroxystearate, polyvinyl alcohol-polyethylene glycol graft copolymer and d-alpha tocopheryl polyethylene glycol 1000 succinate; c) sodium deoxycholate as pharmaceutically acceptable excipient; - it is instantaneously redispersible in physiological relevant media; - it has increased dissolution rate; - it is stable in solid form and in colloid solution and/or dispersion; - its apparent solubility in water is of at least 0.6 mg/mL; - it shows X-ray amorphous character in the solid form; - it has a PAMPA permeability of at least 0.5*10 -6 cm/s when dispersed in distilled water, which does not decrease in time at least for 3 months; - exhibits no positive food effect which allows significant dose reduction and the abandoning of the requirement of taking the drug on an empty stomach; - the variability of exposure is significantly reduced when compared to Zytiga.