C.7. Agents against hepatitis viruses Flashcards
name the Non-Specific (traditional) agents for viral hepatitis
'RITE' Ribavirin IFN-𝝰 Tenofovir Entecavir
how is IFN-𝝰 given?
intramuscular/subcutaneous injection
how is Entecavir & Tenofovir given?
orally
how is Ribavirin given?
oral, IV, aerosol
what type of elimination do traditional agents have?
renal
which traditional agent is teratogenic?
Ribavirin
what is Tenofovir and what does it do?
Nucleotide analog
anti-retroviral agent (NRTI)
what is Tenofovir and Entecavir used for?
Hepatitis B
what are the side effects of Tenofovir?
Nephrotoxicity
Gi distress
what does IFN-𝝰 do against hepatitis virus?
- activation of cytokine receptors–> ↑ activity of JAK-STAT pathway
- selective antiviral activity –> activation of host-cell defense mechanisms
what are the hepatitis indications for IFN-𝝰?
- Hepatitic B-chronic infection (monotherapy/combination)
2. Hepatitic C- acute and chronic infections (in combination with ribavirin)
what are the other clinical indications for IFN-𝝰? (6)
- Kaposi sarcoma (HHV-8)
- hairy cell leukemia
- malignant melanoma
- Papillomatosis
- renal cell carcinoma
- genital warts (HPV)
what type of IFN-𝝰 form can be administered weekly instead of once daily?
Pegylated form IFN
what are the side effects of IFN-𝝰
- Flu-like symptoms
- GI symptoms
- Alopecia
- Bone marrow suppression
- ototoxicity (reversible)
- thyroid dysfunction
- CNS effects (mood disorders, depression)
what are Entecavir and Ribavirin?
Guanosine analogue
side effects of Entecavir
Headache, dizziness
fatigue
Nausea
what does Entecavir do?
inhibits HBV DNA polymerase
what does Ribavirin do?
monophosphate form–> inhibits IMP dehydrogenase–>prevent GMP synthesis
Triphosphate form–> inhibits viral RNA polymerase
what are the indications for Ribavirin?
- hepatitis C infection -acute and chronic (in combination with IFN-𝝰)
- respiratory syncytial virus (aerosol preparation)
- influenza A & B, paramyxovirus, HIV, parainfluenza virus
- viral hemorrhagic fever from Dengue, yellow, Lassa fever, Ebola, Bunyavirus (IV administration)
SE of Ribavirin
- Drug-induced hemolytic anemia (IV)
2. conjunctival, bronchial irritation (aerosol)
what are DAA’S?
direct-acting antivirals
medications targeted at specific steps within the HCV life cycle
*provides eradication rate of >90% in HCV infections
how many DAA’s do we have and how are they classified?
4
defined by their mechanism of actions and therapeutic agent
what are the common side effects of DAA’s?
fatigue
GI distress
headaches
anemia
what DAA’S class are Paritaprevir and Grazoprevir?
NS3/4A protease inhibitors (PI’s)
drug regimens consist of..
2-3 agents
how much time do DAA’s regimens require?
12-16 weeks of treatment
what is the mechanism of DAA’s?
they target non-structural proteins of the virus, resulting in disruption of the viral replication and infection
what DAA’S class does Sofobuvir belong to?
NS5B nucleoside polymerase inhibitors (NPI’S)
what DAA’S class does Dasabuvir belong to?
NS5B non-nucleoside polymerase inhibitors (NNPI’S)
what DAA’S class do Velpatasvir and Elbasvir Belong to?
NS5A inhibitors
