Patent ID: 7998967

Claim:
A method of administering to a host in need thereof an effective amount of methotrexate (MTX), said method comprising: administering to said host said effective amount of a MTX in conjunction with an amount of an MTX toxicity-reducing adjuvant effective to reduce toxicity of said MTX, wherein said MTX toxicity-reducing adjuvant is a 2,2′-anhydropyrimidine of formula (I): wherein R 2 is hydrogen; R 3 is hydroxyl or a halogen; R 4 is hydroxyl; and R 1 is a monoaralkylamino, a lower alkyl containing 1 to 20 carbons, or a substituted lower alkyl containing 1 to 20 carbons, wherein the substituent is selected from an alkoxy, an aryl substituted alkoxy, an imidate, an arylthio and an alkyl substituted arylthio; or a pharmaceutically acceptable salt thereof.