IC9 & 10 Flashcards
What does Tamoxifen act as?
Acts as a selective estrogen receptor modulator (SERM)
Is Cis/ trans isomer of Tamoxifen used for breast cancer?
Trans; to display anti-estrogenic activity
What is tamoxifen used mainly for?
breast cancer
What is pembrolizumab used mainly for?
cervical cancer
Bicalutamide - why cannot use as monotherapy for prostate cancer?
Blocks A -> incr LH secretion -> (+) higher serum testosterone levels
Bicalutamide & Leuprorelin - indication?
Prostate cancer
Prostate growth depends on androgens (T/F)
True
How is pembrolizumab metabolised?
General protein degradation (recall: Mabs are big in size)
Dosage form for pembrolizumab
IV
Does pembrolizumab bind to plasma protein?
No
Does tamoxifen bind to plasma protein?
Yes, Plasma protein binding > 98%
Action of pembrolizumab
PD1-blocker
(basically prevent PD-L1 on tumour cells from binding to PD-1 that would inactivate T cell action
What should be stopped when initiating pembrolizumab? (added back aft initiation)
- Corticosteroids
- Immunosuppressants
Contraindication for pembrolizumab
- Pregnant women
- Hypersensitivity
DDI for tamoxifen
CYP3A4 inhibitor & CYP2D6 inhibitors (incr conc of tamoxifen)
Dosage form for leuprorelin
IV/IM/SC
Action of leuprorelin
GnRH analogue -> inhibits FSH and LH release -> decr androgen synthesis -> decr testosterone production -> apoptosis of prostate cancer cells
How is leuprorelin metabolised?
Degraded proteolytically into inactive peptides
Monitoring for leuprorelin
Measure PSA, LH and FSH in 1st few weeks, and testosterone aft 4 weeks of therapy
C/I for leuprorelin
- Hypersensitivity to leuprorelin/ other GnRH agonists, 2. pre-existing heart disease
- risks for osteoporosis
Dosage form for bicalutamide
Oral tablets
Dosage form for tamoxifen
Oral
Action of bicalutamide
Inhibits androgen receptor -> inhibits AR-dependent transcription -> impairs cell proliferation & triggers apoptosis in cancer cells
Bicalutamide: S or R isomer is active?
R isomer
DDI for Bicalutamide
CYP3A4 inhibitor (incr Bicalutamide conc)
Should Bicalutamide be used as monotherapy for prostate cancer?
No, it is usually used with GnRH analogue
Structure of leuprorelin
Polypeptide
Extent of protein binding: Metformin
Minimal
Elimination of metformin
Renal elimination
MOA for glipizide (SU)
Binds to SU receptor of ATP-sensitive potassium channels -> inhibits K+ efflux, triggers Ca-dependent exocytosis of insulin from pancreatic beta cells
Metabolism of glipizide
Metabolised by liver (hydroxylation)
Which population should not use glipizide?
Should not be used in ppl w/o functional beta cells
Dosage form for sitagliptin (DPP-4i)
Oral
MOA for sitagliptin
Inhibits DPP-4 -> inhibits the breakdown of GLP-1 -> incr glucose- stimulated insulin release
Caution use for sitagliptin
- Caution use in renal impairment
- Caution use in Hx of pancreatitis
Class of liraglutide
GLP-1 agonist
MOA for liraglutide
Binds to GLP-1 -> activates adenyl cyclase -> incr cAMP -> activates PKA -> incr insulin secretion & decr glucagon release
Metabolism for liraglutide
Similar to proteins, no specific organ
Metabolism for empagliflozin
Metabolised in liver (glucuronidation)
Dosage form for liraglutide
SC
MOA for empagliflozin
Inhibits SGLT2 in proximal renal tubule, decr reabsorption of filtered glucose -> decr blood glucose
Extent of protein binding for empagliflozin
Extensively protein bound
Use of empagliflozin could predispose one to UTI (T/F)
True
