ENZYME BIOREACTORS AS DRUGS

Therapy using erythrocyte-encapsulated enzyme has the advantage of prolonging the half-life of the enzyme and maintaining therapeutic blood levels, reducing the dose and frequency of therapeutic interventions, and preventing the need for expensive chemical modification. The therapeutic index can be strongly improved, especially by reducing immunogenic reactions, which are often observed in enzyme therapy administered by the conventional route. Two products are presented in this paper: erythrocyte-encapsulated L-asparaginase and erythrocyte-encapsulated thymidine phosphorylase. For the first, the native enzyme has been the mainstay in the treatment of lymphoblastic leukemia for decades. Improving the therapeutic index by utilizing this new formulation now offers new possibilities in cancer therapy. The second product is proposed for patients diagnosed with mitochondrial neurogastrointestinal encephalomyopathy (MNCIE), an autosomal recessive disorder of nucleotide metabolism caused by mutations in the nuclear TYMP gene (thymidine phosphorylase deficiency). These two approaches illustrate how this new formulation works as an enzyme bioreactor in the treatment of cancer and in enzyme replacement therapy.