Small Animal Clinical Pharmacology - CYF MEDICAL DISTRIBUTION

CHAPTER 15 CANCER CHEMOTHERAPY
Table 15.1 Available formulations of commonly used chemotherapy drugs
Generic name Trade name Manufacturer Formulations
Actinomycin D Cosmegen Merck 0.5 mg vials
BCNU Carmustine BiCNU Bristol Myers Squibb 100 mg vials
Bleomycin Blenoxane Bristol Myers Squibb 15, 30 U per vial
Carboplatin Paraplatin Bristol Myers Squibb 50, 150, 450 mg vials
CCNU Lomustine CeeNU Bristol Myers Squibb 10, 40, 100 mg vials
Chlorambucil Leukeran Glaxo Wellcome 2 mg tablets
Cisplatin Platinol Bristol Myers Squibb 10, 50 mg vials
Cyclophosphamide Cytoxan Bristol Myers Squibb 100, 200, 500 mg, 1, 2 g vials, 25 and 50 mg tablets
Cytoside arabinoside Cytosar-U Pharmacia & Upjohn 100, 500 mg, 1, 2 g vials
Dacarbazine DTIC-Dome Bayer 100, 200 mg vials
Doxorubicin Adriamycin Pharmacia & Upjohn 10, 50, 100 mg vials
Rubex
Bristol Myers Squibb
Epirubicin
Not available in USA
Etoposide VePsid Bristol Myers Squibb 100, 150, 500 mg vials, 1 g vials
Etopophos Bristol Myers Squibb 50 mg capsules
Hydroxyurea Hydrea Bristol Myers Squibb 10, 50, 100 mg vials
Droxia
Bristol Myers Squibb
Idarubicin Idamycin Pharmacia & Upjohn
Ifosfamide Ifex Bristol Myers Squibb 1, 3 g vials
5-Fluorouracil Adrucil Roche 500 mg vial
L-asparaginase Elspar Merck 10,000 IU/vial
Colapase Levnase Aventis
Melphalan Alkeran Glaxo Wellcome 2 mg tablets
Methotrexate Methotrexate Immunex 50, 100, 150, 200 mg vials
2.5 mg tablets
Mitoxantrone
Mitozantrone Novantrone Immunex 20, 25, 30 mg vials
Paclitaxel Taxol Bristol Myers Squibb 30, 100, 300 mg vials
Plicamycin
Mithramycin Mithracin Bayer 2.5 mg vials
Vinblastine Velban Lilly 10 mg vials
Velbe (in Europe)
Vincristine Oncovin Lilly 1, 2, 5 mg vials
Vincristine is believed to be responsible for an increase
in platelet release from bone marrow after administration.
Vincristine binds platelets more avidly
than vinblastine and consequently has theoretical
advantage over vinblastine in the management of
thrombocytopenia.
Mechanisms of drug resistance
Two types of biochemical resistance have been described
in tumor cells insensitive to vincristine. First, mutations
in α- or β-subunits of tubulin lead to decreased binding
of vincristine to tubulin, resulting in resistance to inhibition
of microtubule formation. Tumor cells also become
resistant to the vinca alkaloids through development of
multiple drug resistance mediated by P-gp.
Vincristine
Other names
NCS-67574, LCR, VCR, Oncovin®
Clinical applications
Vincristine is widely used in veterinary oncology. Almost
all combination chemotherapy protocols for canine,
feline and ferret lymphoma incorporate vincristine
into the drug cycle. Remission can be induced with
vincristine-containing protocols in cases of chronic
lymphocytic leukemia and acute lymphoblastic leukemia.
Single-agent vincristine is the treatment of choice
for transmissible venereal tumor and results in a durable
complete remission in over 90% of cases. Vincristine is
a component of the VAC protocol (vincristine, doxorubicin
(Adriamycin®), cyclophosphamide), which has
shown some efficacy against soft tissue sarcomas, including
hemangiosarcoma.
Vincristine and prednisone have also been shown to
increase the platelet count in patients with immunemediated
thrombocytopenia compared to treatment
with prednisone alone. Following administration of vincristine,
a mild transient decrease occurs in platelet
count followed by a peak platelet count 8 days after
drug administration to normal dogs. Platelets formed
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