Virology- Drugs Flashcards
For all these drugs I will list the Mechanism of Action, Uses, and any relevant info/precautions.
Acyclovir
A Synthetic analog of guanosine.
Mechanism of Action- Acyclovir monophosphate is phosphorylated (via viral thymidine kinase) to triphosphate. It then integrates into viral DNA and inhibits DNA replication.
Use- Treats HSV-1/2 infections in immunocompromised patients. IV Acyclovir can also treat Varicella Zoster virus.
Info- Oral Acyclovir can be passed through breast milk, topical is not.
Sitavig
An Acyclovir buccal tablet.
Use- Herpes Labialis (Cold Sores) in immunocompetent adults.
VariZIG
Varicella Zoster Immune Globulin
Valacyclovir
L-Valine Ester of Acyclovir
Mechanism of Action- Converted to Acyclovir. Acyclovir monophosphate is phosphorylated to triphosphate, allowing it to integrate into viral DNA to inhibit replication.
Use- HSV-1/2, VZV (Varicella Zoster) in immunoCOMPETENT adults.
Info- Less dosage than Acyclovir, though no IV available. Occurrence of thrombotic thrombocytopenic purpura.
Famciclovir
Mechanism of Action- Phosphorylated by viral thymidine kinase to penciclovir monophosphate. Penciclovir inhibits DNA Polymerase and DNA replication.
Use- HSV 1/2, VZV
Foscarnet
Synthetic Pyrophosphate analog. Directly inhibits viral enzymes without incorporating into viral DNA. Broad spectrum and the drug of choice in Acyclovir and ganciclovir resistance.
Mechanism of Action- Binds to DNA polymerase, preventing it from cleaving pyrophosphate from the newly added deoxynucleoside triphosphate, this halts DNA elongation. Also inhibits the HIV-1 Reverse transcriptase.
Use- HSV-1/2, VZV, CMV, and HIV-1
Info- With Gancyclovir, 1st line of treatment for CMV retinitis in immunocompromised patients. Can cross the Blood Brain Barrier. Treats acyclovir resistant mucocutaneous HSV infections. Highly Nephrotoxic.
Trifluridine/Viroptic
A 1% Opthalmic solution.
Mechanism of Action- A fluorinated pyrimidine nucleoside. Results in nonfunctional viral proteins, but the true mechanism is not known.
Use- Treats keratoconjunctivitis associated with HSV-1/2. Treats Vaccinia virus, CMV, and some strands of Adenovirus.
Info- May result in ocular burning or stinging.
n-docosanol/Abreva
Mechanism of Action- Unclear. Prevents viral entry
Uses- HSV-1/2 and Respiratory Syncytial Virus. Relieves the pain and helps cold sores heal faster.
Info- Shows synergy in combo with other antiviral nucloside analogs (Acyclovir)
Ganciclovir
Synthetic purine nucleoside analog.
Mechanism of Action- Ganciclovir monophosphate is phosphorylated to triphosphate, allowing it to integrate into Viral DNA, which inhibits DNA polymerase, inhibiting viral DNA replication. (It also penetrated non infected cells, however lower concentrations inhibit viral DNA polymerase rather than host DNA polymerase)
Use- CMV (cytomegalovirus), HSV-1/2, Epstein-Barr virus (Mono).
Info- Cannot resolve CMV infection of the CNS, despite penetrating the CNS. Available in oral/IV versions, oral only approved for CMV.
Valganciclovir
L-valine ester (prodrug) of Ganciclovir.
Mechanism of Action- Converted in vivo to Ganciclovir.
Use- Treats CMV retinitis in AIDS patients.
Info- Only oral form available. NOT equivalent to oral Ganciclovir, so they cannot be substituted for each other.
Cidofovir
Synthetic acyclic purine nucleotide.
Mechanism of Action- Inhibits viral DNA synthesis.
Use- CMV infections in AIDS patients.
Info- Only IV form. Probenecid MUST be administered with each dose. Contraindicated for patients with Probenecid or sulfa drug allergies.
Fomivirsen/Vitravene
First Anti-sense drug to be FDA approved.
Mechanism of Action- Single stranded anti sense piece of DNA, complementary to a sequence within the CMV mRNA. Inhibits viral protein synthesis/replication, does not allow the virus to impart resistance.
Use- Intravitreal (into the eye) treatment for CMV retinitis in AIDS patients.
Info- Ocular inflammation may occur.
Imiquimod
Mechanism of Action- Induces cytokines in mononuclear blood cells. Stimulates IL-1, IL-6, IL-8, TNF, and INF-alpha. Affects both the acquired and innate immune mechanisms.
Use- HPV Genital Warts
Info- Topical treatment
Interferon-Alpha
AKA: Roferon-A, Rebetol, Alferon-N, Wellferon
Mechanism of Action- Binds specifically to membrane receptors, setting off a cascade that inhibits viral replication within a cell. Augments macrophage phagocytic activity an lymphocyte cytoxicity.
Use- Hairy cell leukemia, Kaposi’s sarcoma, condyloma acuminata, chronic HBV, chronic HCV infection, melanoma.
Info- Psoriasis and asthma may worsen with treatment.
PEG-INF/Pegasys/Peg-Intron
Mechanism of Action- PEG increases the half life of INF. Results in better efficacy and less serious side effects.
Use- Treating HCV in combination with ribavirin.
Info- Side effects decrease as treatment continues (mainly psychiatric and nausea).
Ribavirin/Virazole
Synthetic nucleoside.
Mechanism of Action- Prevents nucleic acid synthesis.
Use- Respiratory Syncytial Virus, Influenza A/B, RSV.
Info- Fallen out of favor due to possible birth defects in pregnant women and patients . The primary toxicity is hemolytic anemia.
INF-Alpha + Ribavirin (Rebetol)
Mechanism of Action- Unknown. But more effective than either drug alone.
Use- Chronic HCV infections where INF-alpha monotherapy failed.
Victrelis/Boceprevir
Mechanism of Acion- Inhibits the Hepatitis C non-structural protein 3 (NS3) serine protease.
Use- Used in combination with Peginterferon-alpha and ribavirin for chronic Hepatitis C infections w/ liver disease.
Info- Orally administered as capsule.
Incivek/Incivo (Telaprevir)
Mechanism of Action- Hepatitis C NS3/4A protease inhibitor.
Use- Used in combination with peginterferon alpha and ribavirin for treatment of genotype 1 chronic hepatitis (CHC) w/ liver disease.
Amantadine/Symmetrel
Synthetic tricyclic amine.
Mechanism of Action- Interferes with the ion channel function of the M2 protein and acts on hemaglutin in the viral protein which facilitates viral adsorption and entry. Ineffective against Influenza B, as it lacks M2.
Use- Influenza A. In combination with INF-alpha can treat HCV infections.
Info- Recommended for all high risk non immunized patients at the 1st sign of flu.
Rimantadine/Flumadine
Alpha-methyl derivative of Amantadine.
Mechanism of Action- Possibly affects viral uncoating.
Use- Influenza A
Info- Taken with milk, as it may upset stomach. Not recommended for pregnant women.
Zanamivir/Relenza
Neuraminidase inhibitor
Mechanism of Action- Inhibits viral neuraminidase and prevents viral replication.
Use- Uncomplicated Influenza A and B.
Info- Not recommended in COPD or asthma patients. Caused skeletal birth defects in animals.
Oseltamivir/Tamiflu
Pharmalogically similar to Zanammivir, but structurally different.
Mechanism of Action- Prodrug that is hydrolyzed to oseltamivir carboxylate in vivo. Inhibits viral neuraminidase and prevents viral replication.
Use- Influenza A and B
Info- Patient must be over 1 year of age.
I just want to take this opportunity…..
To thank Terry for these shorts! Thank you!!!
Maraviroc/Selzentry
Anti-Retroviral
Mechanism of Action- Blocks CCR5 to prevent entry of virus into macrophages.
Use- HIV
Tivicay
Anti-Retroviral
Mechanism of Action- An integrase strand transfer inhibitor. Interferes with one of the enzymes responsible for HIV replication.
Use- HIV
What is the Standard of Care regimen for retroviruses?
1-2 protease inhibitors and 2 nucleoside reverse transcriptase inhibitors to block viral replication at different stages.
Truvada
Combo of EMTRIVA and VIREAD. A daily pill to prevent HIV infection.
Palivizumab/Synagis
A monoclonal antibody treatment. The ONLY one approved so far
Mechanism of Action- Works against a specific viral surface glycoprotein (F Protein).
Use- RSV infection
