Quiz 2 drugs Flashcards
Why is mesna necessary with Cyclophosphamide administration?
it is a prodrug activated with multiple active forms, one of which is converted to acrolein (cytotoxic and damages bladder), and mesna binds acrolein
What is the PK of cyclophosphamide?
Metabolized by CYP P450 enzymes to active/inactive metabolites, 80% renal elimination
What is the acute/delayed toxicity of cyclophosphamide?
A: N/V (high dose)
D: BM toxicity, mucositis, azoospermia, ovarian failure, secondary cancers, alopecia, hemorrhagic cystitis and SIADH
What is the generic/brand name of the principle Platinum drug (alkylating-like) used for MCC?
Cisplatin (Platinol)
What is the MoA of Cisplatin?
Forms primarily intrastrand cross links (also interstrand and mono) as well as binds to nuclear and cytoplasmic proteins
What is the dosage and administration of Cisplatin?
IV
What are the acute/delayed toxicities of Cisplatin?
A: N/V (high dose)
D: Nephrotoxicity, peripheral sensory neuropathy, ototoxicity, nerve dysfunction
What is the principle drug used as a folic acid analog?
Methotrexate
What is the MoA of Methotrexate?
Inhibits DHFR and prevents conversion of FA to THF, the methyl-donor for thymidylate synthase. Also affects nucleotide synthesis minor mechanisms
What is the dosage and admin of MTX?
PO, IV, IT (high dose MTX with leucovorin after)
What is the relevant PK of MTX?
Renal elimination, dose with urinary alkalinization and hyper-hydration
What is the acute/delayed toxicity of MTX?
A: N/V (scales with dose)
D: myelosuppression, mucositis, nephrotoxicity, hepatotoxicity, pneumonitis
What are significant drug interactions for MTX?
Salicylates, sulfonamides, probenecid, penicillin, NSAIDs
What is the generic/brand name of the principle Nitrogen mustard used in MCC?
Cyclophosphamide (cytoxan)
What is the MoA of Cyclophosphamide?
It forms primarly intERstrand DNA crosslinks (also intRA and mono) resulting in inhibition of DNA synthesis and function
What are the dosage and admin of Cyclophosphamide?
D: IV, PO
A: High dose with mesna
What antidote can be given for MTX adminstration?
carboxypeptidase G2
What two fluorinated Pyrimidine analogs are used to treat cancer in MCC?
Fluorouracil “5-FU” and Capecitabine (Xeloda)
What is the MoA of the fluorinated pyrimidine analogs used in MCC?
Suicide inhibition of Thymidylate synthase; incorporation of F-UTP into RNA, FdUTP into DNA
What are the doseage and admin of 5-FU and Capecitabine?
5- IV
C-PO, with food b.i.d.
What are the PK of 5-FU and Capecitabine?
Extensive liver processing
What is the acute/delayed toxicity for 5-FU and Capecitabine?
A: N/V (low)
D: HFS, Myelosuppression, diarrhea, and coronary vasospasm
What are the significant drug interactions of Capecitabine?
CYP2C9 inhibitors (Warfarin)