Abstract: A method of treatment of: i) HIV-1 infections in mammals, including humans; or ii) HBV infections in mammals, including humans; which method comprises the administration to the human in need of such treatment, an effective amount of the (R)-enantiomer of the triphosphate of a compound of formula (A) or a pharmaceutically acceptable salt thereof; and compounds for use in the method.

Abstract: Combinations of antiretroviral nucleoside reverse transcriptase inhibitors, and methods for their use in treating retroviral infections, are provided. In one embodiment, the combinations include non-thymidine nucleoside antiretroviral agents, such as tenofovir-DF, abacavir, APD and DAPD, that select for the K65R mutation and relatively low doses of zidovudine (AZT) or other thymidine nucleoside antiretroviral agents. The thymidine nucleoside antiretroviral agents retard development of the K65R mutation, and at the low doses, are less likely to produce side effects. In another embodiment, the combinations include DAPD and AZT. DAPD retards the development of TAMs, and AZT retards the development of the K65R mutation. In a third embodiment, the combinations include adenine, cytosine, thymidine, and guanine nucleoside antiviral agents, in further combination with at least one additional antiviral agent that works via a different mechanism than a nucleoside analog.

Abstract: The present invention is directed to compounds, compositions and methods for treating or preventing viral infections, in particular, HIV, HBV, and HCV, in human patients or other animal hosts. The compounds are 3?-azido-2?,3?-dideoxy purine nucleosides or phosphonates, and pharmaceutically acceptable, salts, prodrugs, and other derivatives thereof. In particular, the compounds show potent antiviral activity against HIV-1 resistance mutants including HIV-1K65R, HTV-1K70E, HIV-1L74V, HIV-1M184V, HIV-1Q151M and inhibitory activity against HIV-1 RT harboring TAMS or insertion mutations including HIV-1AZT3, HIV-1AZT7, HIV-1AZT9, HIV-1Q151M, or HIV-169insertion. In one embodiment, the compounds are 3?-azido-ddA, 3?-azido-ddG, or combinations thereof, administered with one or more additional antiviral agents that select for TAM mutations and/or the M 184V mutation, along with a pharmaceutically acceptable carrier.

Abstract: 2?-Fluoro-nucleoside compounds are disclosed which are useful in the treatment of hepatitis B infection, hepatitis C infection, HIV and abnormal cellular proliferation, including tumors and cancer. The compounds have the general formulae: wherein Base is a purine or pyrimidine base; R1 is OH, H, OR3, N3, CN, halogen, CF3, lower alkyl, amino, loweralkylamino, di(lower)alkylamino, or alkoxy; R2 is H, phosphate, or a stabilized phosphate prodrug; acyl, or other pharmaceutically acceptable leaving benzyl, a lipid, an amino acid, peptide, or cholesterol; and R3 is acyl, alkyl, phosphate, or other pharmaceutically acceptable leaving group; or a pharmaceutically acceptable salt thereof.

Abstract: A method and composition for the treatment, prevention and/or prophylaxis of a host, and in particular, a human, infected with Epstein-Barr virus (EBV), is provided that includes administering an effective amount of a 5-substituted uracil nucleoside or its pharmaceutically acceptable salt or prodrug, optionally in a pharmaceutically acceptable diluent or excipient.

Abstract: The present invention provides an isolated HIV-1 mutant and isolated nucleic acid molecules comprising HIV-RT coding sequences harboring a novel mutation in the S68 codon, and in particular, deletions of the S68 codon. This novel deletion reduces the sensitivity of HIV to various nucleoside reverse transcriptase inhibitors. Methods of using this mutation for selecting effective antiretroviral agents in vitro and in vivo, methods for monitoring infection progression in HIV-infected individuals and methods for avoiding the emergence of and/or to treat individuals infected with HIV comprising mutations at the S68 codon of HIV-RT, e.g., S68del, are provided.

Abstract: A class of 2?-fluoro-nucleoside compounds are disclosed which are useful in the treatment of hepatitis B infection, hepatitis C infection, HIV and abnormal cellular proliferation, including tumors and cancer.

Abstract: A method and composition for the treatment, prevention and/or prophylaxis of a host, and in particular, a human, infected with Epstein-Barr virus (EBV), is provided that includes administering an effective amount of a 5-substituted uracil nucleoside or its pharmaceutically acceptable salt or prodrug, optionally in a pharmaceutically acceptable diluent or excipient.

Abstract: The present invention discloses a method for treating HIV that includes administering ?-D-D4FC or its pharmaceutically acceptable salt or prodrug to a human in need of therapy in combination or alternation with a drug that induces a mutation in HIV-1 at a location other than the 70(K to N), 90 or the 172 codons of the reverse transcriptase region. Also disclosed is a method for using ?-D-D4FC as “salvage therapy” to patients which exhibit drug resistance to other anti-HIV agents. ?-D-D4FC can be used generally as salvage therapy for any patient which exhibits resistance to a drug that induces a mutation at other than the 70(K to N), 90 or the 172 codons.

Abstract: A method and composition for treating a host infected with a Caliciviridae virus, such as a Norovirus, comprising administering an effective treatment amount of a described modified nucleoside or a pharmaceutically acceptable salt thereof, is provided.

Abstract: The present invention relates to the use of a dioxolane thymine compound according to the chemical structure of Formula (I): where R1 is H, an acyl group, a C1-C20 alkyl or ether group, a phosphate, diphosphate, triphosphate or phosphodiester group, for use in the treatment of HIV infections which exhibit resistance to 3TC and/or AZT. Preferably, compounds according to the present invention are combined with at least one anti-HIV agent which inhibits HIV by a mechanism other than through the inhibition of thymidine kinase (TK). These agents include those selected from among nuleocoside reverse transcriptase inhibitors (NRTI), non-nucloeoside reverse transcriptase inhibitors, protease inhibitors, fusion inhibitors, among others.

Abstract: A process for the resolution of a racemic mixture of nucleoside enantiomers that includes the step of exposing the racemic mixture to an enzyme that preferentially catalyzes a reaction in one of the enantiomers. The nucleoside enantiomer (?)-2-hydroxymethyl-5-(5-fluorocytosin-1-yl)-1,3-oxathiolane is an effective antiviral agent against HIV, HBV, and other viruses replicating in a similar manner.

Abstract: A method for the treatment of a host, and in particular, a human, infected with hepatitis B virus (HBV) is provided that includes administering an effective amount of a ?-L-nucleotide, optionally in combination therapy with other drugs for the treatment of HBV or human immuno-deficiency virus (HIV).

Abstract: A method and composition for the treatment of HIV and HBV infections in humans is disclosed that includes administering an effective amount of 2-hydroxymethyl-5-(5-fluorocytosin-1-yl)-1,3-oxathiolane, a pharmaceutically acceptable derivative thereof, including a 5? or N4 alkylated or acylated derivative, or a pharmaceutically acceptable salt thereof, in a pharmaceutically acceptable carrier. A process for the resolution of a racemic mixture of nucleoside enantiomers is also disclosed that includes the step of exposing the racemic mixture to an enzyme that preferentially catalyzes a reaction in one of the enantiomers.

Abstract: A process for the resolution of a racemic mixture of nucleoside enantiomers that includes the step of exposing the racemic mixture to an enzyme that preferentially catalyzes a reaction in one of the enantiomers. The nucleoside enantiomer (?)-2-hydroxymethyl-5-(5-fluorocytosin-1-yl)-1,3-oxathiolane is an effective antiviral agent against HIV, HBV, and other viruses replicating in a similar manner.

Abstract: A method for the treatment of a host, and in particular, a human, infected with hepatitis B virus (HBV) is provided that includes administering an effective amount of a ?-L-nucleotide, optionally in combination therapy with other drugs for the treatment of HBV or human immuno-deficiency virus (HIV).

Abstract: A class of 2?-fluoro-nucleoside compounds are disclosed which are useful in the treatment of hepatitis B infection, hepatitis C infection, HIV and abnormal cellular proliferation, including tumors and cancer.

Abstract: A method and composition for the treatment of HIV and HBV infections in humans and other host animals is disclosed that includes the administration of an effective amount of a [5-carboxamido or 5-fluoro]-2?,3?-dideoxy-2?,3?-didehydro-pyrimidine nucleoside or a [5-carboxamido or 5-fluoro]-3?-modified-pyrimidine nucleoside, or a mixture or a pharmaceutically acceptable derivative thereof, including a 5? or N4 alkylated or acylated derivative, or a pharmaceutically acceptable salt thereof, in a pharmaceutically acceptable carrier.

Abstract: A method for the treatment or prevention of Flaviviridae infections, in particular, hepatitis C virus infection, in a host, and in particular, a human, is provided that includes administering an effective amount of a ?-L- or ?-D-2?,3?-dideoxynucleoside or a pharmaceutically acceptable salt or prodrug thereof, optionally in a pharmaceutically acceptable diluent or excipient.

Abstract: Method for the sterospecific preparation of 2? or 3? deoxy and 2?,3?-dideoxy-?-L-pentafuranonucleoside compounds. 2? or 3? deoxy and 2?,3?-dideoxy-?-L-pentofuranonucleoside compounds are also described. Finally, the invention concerns the use of these compounds, and particularly 2?,3?dideoxy-?-L-fluorocytidine, as drugs, and especially as anti-viral agents.