Introduction

Name

• Doxorubicin.

Class of drug

• Cytotoxic anthracycline antibiotic.
• Antineoplastic.

Description

Chemical name

• (7S,9S)-7-[(2R,4S,5S,6S)-4-amino-5-hydroxy-6-methyloxan-2-yl]oxy-6,9,11-trihydroxy-9-(2-hydroxyacetyl)-4-methoxy-8,10-dihydro-7H-tetracene-5,12-dione

Molecular formula

• C₂₇H₂₉NO₁₁.

Molecular weight

• 543.52 g/mol.

Physical properties

• Doxorubicin HCl occurs as a lyophilized, red-orange powder.
• Freely soluble in water, slightly soluble in normal saline, and very slightly soluble in alcohol.

Storage requirements

• Lyophilized powder for injection should be stored in a dry place and away from direct sunlight:
  • After reconstitution, it is stable for 24 h at room temperature and for 48 h if refrigerated (according to manufacturer).
  • However, one study reported stability for 6 months when a solution of 2 mg/mL was refrigerated and at least for 1 month when frozen at -20°C/-4°F.
• The commercially available solution for injection is stable for 18 months when stored in the refrigerator and protected from light.
• The manufacturer states that after reconstitution, the multi-dose vials may be stored for up to 7 days at room temperature and up to 15 days in the refrigerator.

Uses

Indications

• Used to treat a variety of lymphomas, leukemias, sarcomas and carcinomas in all species.
• In horses, the most likely indication is for lymphomas and carcinomas, which were most responsive to treatment in a small case series:
  • Melanomas were not responsive to this treatment modality.
  • Some sarcoids appeared to respond to doxorubicin treatment.
• It may be used alone or in combination with other antineoplastic therapies, such as radiation therapy or alongside other cytotoxic drugs.
• Although it possesses antimicrobial properties, doxorubicin’s cytotoxic effects preclude its use to treat infections.

Administration

Pharmacokinetics

Precautions

Interactions

with other drugs

• Digoxin Digoxin: reduction in serum digoxin levels.
• Barbiturate: increases plasma clearance of doxorubicin.
• Cyclophosphamide: increases risk of cardiotoxicity and cyclophosphamide-induced cystitis.
• Heparin Heparin: forms precipitate with doxorubicin.

Adverse Reactions

Further Reading

Publications

Refereed Papers

• Recent references from PubMed and VetMedResource.
• Theon A P, Pusterla N, Magdesian K G & Wilson W D (2013) Phase I dose escalation of doxorubicin chemotherapy in tumor-bearing Equidae. J Vet Intern Med 27 (5), 1209-1217 PubMed.
• Theon A P, Pusterla N, Magdesian K G et al (2013) A pilot phase II study of the efficacy and biosafety of doxorubicin chemotherapy in tumor-bearing Equidae. J Vet Intern Med 27 (6), 1581-1588 PubMed.