Effective treatment of murine leukemia with antisense poly-2 '-O-(2,4-dinitrophenyl)-oligoribonucleotides

Two antisense poly-2'-O-(2,4-dinitrophenyl) -oligoribonucleotides (poly-DNP -RNA) have been synthesized and tested for the treatment of murine leukemia . Compound I was designed as a bifunctional inhibitor of either the reverse transcriptase (RT) activity or viral envelope synthesis in Moloney murine leukemia virus (MMLV), Compound II was designed as a trifunctional inhibito r of either RT activity or envelope synthesis or protease synthesis in MMLV , Administration of either I or II to MMLV-infected mice for 3 weeks decrea sed viremia gradually to below the level detectable by RT-PCR, Viremia did not reappear 8 weeks after termination of treatment, when most of the mice were killed for autopsy. All infected but untreated mice died within 6 mont hs with enlarged spleens that exhibited abnormal histologic signs and were found by PCR to contain the DNA of integrated viral genome, The infected mi ce that had been treated subsequently with adequate dosage of compound I or II had normal spleens, continued to live on, and had no integrated MMLV ge nome in their spleen and bone marrow samples, The effective i.p, dosage (ED 50) for compounds I and II are 0.25 and 0.1 mg/kg, respectively, which are 200-fold to 500-fold lower than that of the monofunctional RT inhibitor pol y-DNP-oligo A. The estimated effective oral dosage of compound II is 1.2 mg /kg.