Summary: Dogs receiving Doxorubicin compared to Dactinomycin as part of a multi-agent protocol were compared. Median time to first remission was not significantly different between the 2 groups. However, median duration of remission and median survival time was significantly longer for dogs treated with Doxorubicin. There were no significant differences in toxicity noted between the 2 groups

Publication: Khanna C, Lund E, Redic K, Hayden D, Bell FW, Goullaud R, Klausner JS. A randomized trial of doxorubicin versus dactinomycin in the treatment of canine lymphosarcoma. J Am Vet Med Assoc. 213(7):985-90, 1998.

Objective: To compare efficacy and toxicity of 2 multi-agent chemotherapeutic protocols, similar in all respects except that one incorporated dactinomycin and the other incorporated doxorubicin, for treatment of dogs with malignant lymphoma.

Design: Randomized double blind controlled trial.

Animals: 45 dogs with malignant lymphoma.

Methods: Dogs were randomly assigned to a doxorubicin or dactinomycin treatment group. Time to first remission, duration of first remission, survival time, and prevalence of toxicoses, particularly number of episodes of dose-limiting neutropenia and gastrointestinal toxicoses were compared between groups.

Results: 37 dogs received at least 1 dose of doxorubicin (21 dogs) or dactinomycin (16 dogs). Median time to first remission was not significantly different between groups, but median duration of first remission and median survival time were significantly longer for dogs in the doxorubicin treatment group than for dogs in the dactinomycin treatment group. Numbers of dogs that died, numbers of episodes of dose-limiting neutropenia, and numbers of episodes of gastrointestinal toxicoses were not significantly different between groups.
Conclusions: A multi-agent chemotherapeutic protocol incorporating doxorubicin was significantly more effective in dogs with malignant lymphoma than a similar protocol incorporating dactinomycin. Despite the lower cost and lack of cardiotoxicity, dactinomycin is not an equivalent substitute for doxorubicin in the initial treatment of dogs with malignant lymphoma.