Introduction – Anti-Virals
- Drugs
- HIV anti-viral medications or highly active antiretroviral therapy (HAART)
- nucleoside analog reverse transcriptase inhibitors (NRTI)
- non-nucleoside reverse transcriptase inhibitors (NNRTI)
- fusion inhibitors
- integrase inhibitors
- protease inhibitors
- HCV anti-viral medications
- other anti-viral medications
- HIV anti-viral medications or highly active antiretroviral therapy (HAART)
- Clinical use
- viral infections
- for HIV infections, regimen often consists of 3 drugs to prevent resistance: 2 NRTIs and an integrase inhibitor or protease inhibitor
- increasingly, regimens are tailored to viral genomics and resistance patterns
- for HCV infections, regimen also consists of multiple drugs to prevent resistance
- for HIV infections, regimen often consists of 3 drugs to prevent resistance: 2 NRTIs and an integrase inhibitor or protease inhibitor
- viral infections
| HIV Highly Active Antiretroviral Therapy (HAART) | ||
| Drugs | Mechanism of Action | High Yield Adverse Effects |
| Abacavir (ABC) Didanosine (DDL) Emtricitabine Lamivudine Stavudine Zidovudine (ZDV) Tenofovir (a nucleotide rather than nucleoside) | NRTI | Bone marrow suppressionPeripheral neuropathyLactic acidosisAnemia (ZDV)Pancreatitis (DDL)Drug hypersensitivity (ABC) (HLA-B*5701 positive patients)ZDV can be used during pregnancy |
| Delavirdine Efavirenz Nevirapine | NNRTI | Drug rashLiver toxicityVivid dreams (efavirenz)Neurologic symptoms (efavirenz)Contraindicated in pregnancy (efavirenz and delavirdine) |
| Atazanavir Darunavir Fosamprenavir Indinavir Lopinavir Ritonavir Saquinavir | Protease inhibitors, preventing maturation of new viruses | HyperglycemiaGastrointestinal upsetCushing-like syndromeRenal toxicity (indinavir)Thrombocytopenia (indinavir)Inhibits cytochrome P450 (ritonavir) |
| Dolutegravir Elvitegravir Raltegravir | Integrase inhibitors, inhibiting integration of viral genome into host cell chromosome | Increased serum creatine kinase |
| Enfuvirtide Maraviroc | Fusion inhibitorsEnfuvirtide: inhibits viral entry by binding to viral gp41Maraviroc: inhibits viral entry by binding CCR-5 on host T-cells, inhibiting its interaction with viral gp120 | Injection site reactions (enfuvirtide)Peripheral neuropathy (enfuvirtide)Hepatotoxicity (maraviroc) |
| Griseofulvin | Disrupts mitosis via microtubule dysfunctionEspecially targets keratin-containing tissues such as nailsFungistatic | TeratogenicDisulfiram-like reactionNeurologic symptomsconfusionheadachesInduces cytochrome P450 |
| HCV Anti-Viral Medications | |||
| Drug | Mechanism of Action | High Yield Adverse Effects | Indications |
| Ribavirin | Guanine nucleotide synthesis inhibition | Hemolytic anemiaTeratogenic | RSVHCV |
| Interferons | Glycoprotein analogs (normally synthesized by infected cells, as well as tumor cells) | Flu-like symptomsNeutropeniaMyopathyDepression | HBVHCVKaposi sarcomaCondyloma acuminatum |
| Ledipasvir | Viral phosphoprotein (NS5A) inhibitor, which disrupts viral replication | FatigueHeadache | HCV |
| Simeprevir | HCV protease (NS3/4A) inhibitor, disrupting replication | PhotosensitivityPruritusFatigueHeadache | HCV |
| Sofosbuvir | HCV RNA-dependent RNA polymerase (NS5B) inhibitor | FatigueHeadacheNausea | HCV |
Different Classes of Anti-Virals
- Nucleoside/nucleotide analogues: These medications interfere with the replication of viral genetic material by mimicking the structure of nucleotides, which are the building blocks of DNA and RNA. They are commonly used to treat infections caused by herpesviruses, hepatitis B and C viruses, and HIV.
- Protease inhibitors: Protease inhibitors target specific viral enzymes that are necessary for viral replication. They are commonly used to treat infections caused by HIV and hepatitis C virus.
- Entry inhibitors: Entry inhibitors prevent the virus from entering the host cell by blocking specific receptors or fusion proteins. They are commonly used to treat infections caused by HIV.
- Polymerase inhibitors: Polymerase inhibitors target viral enzymes that are essential for viral replication. They are commonly used to treat infections caused by influenza viruses.
- Immunomodulators: Immunomodulators enhance the immune system’s ability to fight viral infections by stimulating the production of interferons, cytokines, and other immune system molecules. They are commonly used to treat infections caused by hepatitis B and C viruses.
Studies- Anti-Virals
There are numerous studies related to antiviral medications, including:
- Clinical trials: Clinical trials are studies that test the safety and efficacy of new antiviral medications in humans. These trials are designed to determine the optimal dosing regimen, evaluate the safety and tolerability of the medication, and assess the efficacy in treating specific viral infections.
- Resistance studies: Antiviral resistance is a growing concern, as viruses can quickly develop resistance to existing medications. Resistance studies investigate the mechanisms by which viruses become resistant to antiviral medications and identify new targets for drug development.
- Pharmacokinetic studies: Pharmacokinetic studies investigate how antiviral medications are absorbed, distributed, metabolized, and eliminated by the body. These studies can help to determine the optimal dose and duration of treatment for different types of viral infections.
- Drug-drug interaction studies: Antiviral medications can interact with other medications, leading to adverse effects or reduced efficacy. Drug-drug interaction studies investigate how antiviral medications interact with other commonly used medications and identify potential drug interactions.
- Mechanism of action studies: Mechanism of action studies investigate how antiviral medications work at the cellular and molecular level. These studies can help to identify new drug targets and improve the design of existing antiviral medications.
- Epidemiological studies: Epidemiological studies investigate the prevalence, incidence, and distribution of viral infections in different populations. These studies can help to identify new targets for drug development and assess the efficacy of existing antiviral medications in different populations.
Overall, studies related to antiviral medications are important for improving the treatment of viral infections. They can help to identify new drug targets, optimize treatment regimens, and reduce the risk of drug resistance.
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