Abstract: The present invention provides a method of optimizing therapeutic efficacy and reducing toxicity associated with 6-mercaptopurine drug treatment of an immune-mediated gastrointestinal disorder such as inflammatory bowel disease. The method of the invention includes the step of determining the level of one or more 6-mercaptopurine metabolites in the patient having an immune-mediated gastrointestinal disorder.

Abstract: The present invention relates to dideoxynucleoside analog compounds containing a dideoxy ribofuranosyl moiety that exhibit selective anti-viral activity coupled with substantially low toxicity toward the host cells. In particular, the compounds according to the present invention show potent inhibition of the replication of the human immunodeficiency virus (HIV), while remaining substantially inert toward host cell DNA. Compounds according to the present invention exhibit primary utility as agents for inhibiting the growth or replication of retroviruses, particularly HIV. The compounds of the invention comprise a (2,3?-dideoxy-?-ribofuranosyl) ring coupled to a heterocyclic nucleobase that lacks an “O2 carbonyl”, that enables them to selectively react with and inhibit viral reverse transcriptase, while remaining substantially unreactive toward human DNA polymerases.