The present invention relates to a therapeutic composition including a ceramidase mixture and a pharmaceutically acceptable carrier, where the ceramidase mixture includes an inactive acid ceramidase precursor and an active acid ceramidase. The invention also relates to a method of acid ceramidase treatment, including formulating the acid ceramidase used in said treatment as a ceramidase mixture, where the ceramidase mixture includes an inactive acid ceramidase precursor and an active acid ceramidase. The invention further relates to a method of producing a therapeutic composition including providing a medium containing an inactive acid ceramidase precursor; incubating the medium under conditions effective to transform a portion of the inactive acid ceramidase precursor to active acid ceramidase; and recovering the incubated medium as a ceramidase mixture comprising the inactive acid ceramidase precursor and an active acid ceramidase. The present invention also relates to preparation of a therapeutic composition of a ceramidase lacking acid sphingomyelinase.