Mon Test- week 4 day 2- pharma Flashcards
What are the general mechanisms antivirals act? 6 things
Block:
1) viral attachment to cell membrane
2) entry of cell via endocytosis or fusion
3) uncoating of virus
4) viral DNA or RNA replication (and transcription for retroviruses)
5) viral protein synthesis by cell
6) viral exit from cell
Are antivirals effective agains latent viruses?
no, only actively replicating
What are the main difference in DNA and RNA viruses regarding prevention and tx?
DNA: Easier to prevent with vaccines vs RNA viruses due to relative stability of DNA viruses. More treatments than for RNA viruses.
RNA: Fewer treatments compared to DNA viruses
– Breakthrough in hepatitis C treatment in last decade
– Antiretroviral treatment now highly effective
What are the three most common agents for antiretroviral therapy?
- reverse transcriptase inhibitor (RTI)
- protease inhibitor (PI)
- integrase strand transfer inhibitor
What is contemporary antiretroviral therapy?
uses combinations of 2 or 3 agents to maximize suppression and minimize ADRs
What are the ADRs with antiretroviral therapy?
- Metabolic effects (e.g., fat redistribution, immune reconstitution syndrome) with NRTIs, NNRTIs, PIs
- Glucose metabolism abnormalities, osteoporosis, QTc prolongation with PIs
What are DDIs with antiretroviral agents?
almost none for NRTIs (Nucleoside reverse transcriptase inhibitors) , but many for other agents.
Check with pharmacist when considering prescribing a macrolide (bacterial infection) or triazole (fungal infection)
two drugs you should be careful prescribing and consult with pharmacists for people on antiretroviral therapy
macrolide (bacterial inf) and triazole (fungal)
What is the most common class of drugs used in combination therapy for people with HIV?
NRTI (emtricitabine and TDF/TAF)
What are the main mechanism of action for herpes virus agents?
most agents are nucleoside inhibitors, competitively binding during DNA transcription and thus terminating it
4 main herpes agents and their benefits?
- Acyclovir (less side effects)
- Valacyclovir (more absorbtion)
- Famcyclovir single oral dose but more side effects
- Docosanol - OTC
what are herpes agents ADRs?
nausea, headache (lower incidence with acyclovir)
what are herpes agents DDIs?
: few with acyclovir/valacyclovir (weak CYP 1A2 inhibitors), famciclovir: almost none
Which herpes agent is safe to use during pregnancy and lactation?
acyclovir
What are the. herpes agents for HSV1, HSV2, VZV, EBV, CMV?
- HSV-1 and HSV-2: acyclovir/valacyclovir, famciclovir
- VZV: acyclovir (chickenpox and shingles), valacyclovir (shingles), famciclovir (shingles)
- EBV: no agent approved for EBV—supportive care only
- CMV: valgancyclovir (immunosupression is main concern)
What is MOA for influenza drugs?
blocks viral RNA transcription and replication (baloxavir) or inhibit virus exit from cell (amivers)
Three agents for influenza infection?
- oseltamivir
- zanamivir b
- baloxavir single dose, less efficient but less side effects
Influenza agents ADRs?
nausea, vomiting, headache (minimal for baloxavir)
Influenza agents DDIs?
nothing
What influenza agent is safe diring pregnancy?
Oseltamivir (tamilfu)
When should one start antiviral flu therapy?
Start treatment within 2 days of symptoms in otherwise healthy patients; in patients at high risk of severe illness there is benefit seen even at start 5 days after symptom onset; later start OK in immunocompromised; longer therapy needed
HepC agents MOA?
multiple MOAs for the 3 classes of agents; referred to as “direct acting antivirals” (DAAs); these agents are not taken up by non-infected cells
three classes of drugs for HepC? What do they end with to easier figure out a class? how long is the tx?
- NS3-4 protease inhibitors; suffix is -previr
- NS5a inhibitors; suffix is -asvir
- NS5b nucleoside/non-nucleoside inhibitors; suffix is –buvir
Used in combinations typically, 8-12 weeks
ADRs of hepC agents?
fatigue, headache, insomnia
