RabacfosadineDose, contraindications and adverse effects for Dogs.

Nucleotide analog antineoplastic prodrug; inhibits DNA polymerase to halt cell division, FDA-approved specifically for canine lymphoma. Rabacfosadine is indicated for the treatment of lymphoma in dogs. The drug appears to show promise for combined chemotherapy of naïve canine lymphoma as well as relapsed or refractory lymphoma,2 and as a single agent for the treatment of canine cutaneous Tcell lymphoma and multiple myeloma. In 2 pilot field studies, the overall response rate (ORR) in 22 dogs with B-cell or T-cell lymphoma rec

Rabacfosadine is a guanine nucleotide analogue. Intracellularly, the prodrug is sequentially hydrolyzed, deaminated, and then undergoes 2 separate phosphorylation reactions. Its active form, 9-[2-(phosphonomethoxy)ethyl] guanine diphosphate (PMEGpp), is a potent, chain-terminating inhibitor of the major deoxyribonucleic acid (DNA) polymerases.

The drug is contraindicated in dogs with pulmonary fibrosis, a history of chronic pulmonary disease that could lead to fibrosis, and in West Highland white terriers or other breeds with a genetic predisposition for the development of pulmonary fibrosis. Rabacfosadine was associated with life-threatening or fatal pulmonary fibrosis in a small percentage of patients in the field studies (less than 5%). Pul- monary fibrosis may be an idiosyncratic toxicity.

The most common acute adverse effects observed with rabacfosadine in dogs include diarrhea, vomiting, decreased/loss of appetite, weight loss, lethargy, and neutropenia. Leukopenia nadirs were observed between Days 6 and 9 following administration, with recovery by Day 12. Other adverse effects include hematochezia, tachypnea, dyspnea, tachycardia, thrombocytopenia, anemia, hypokalemia, hypophosphatemia, otitis media, and dermal changes (eg, alopecia, dermatitis, pyoderma).

■ Baseline complete blood count, serum biochemistry profile, urinalysis, and thoracic radiographs ■ CBC 7 days after the first treatment and immediately before each subsequent treatment ■ Baseline and periodic (eg, every 2 to 3 treatments) serum biochemistry profile, including renal and hepatic…