Rabacfosadine
**Rabacfosadine** is a novel antineoplastic agent used primarily in veterinary medicine for the treatment of canine lymphoma (both B-cell and T-cell) and multiple myeloma. > **Clinical Warning:** This is a potent cytotoxic drug. It must only be prepared and administered by trained personnel following strict chemotherapeutic safety guidelines.
Mechanism: Rabacfosadine is a **prodrug** of the nucleotide analogue **PMEG** (9-(2-phosphonylmethoxyethyl)guanine). Once converted, it acts by **inhibiting DNA polymerases** → preventing DNA synthesis → causing **cytotoxicity** and apoptosis in rapidly dividing cells, such as neoplastic lymphocytes.
Dosing by species
- Lymphoma (B and T cell) and multiple myeloma · 0.82-1 mg/kg · IV · once every 21 days · over 30 min · Has been used in combination with doxorubicin at weeks 0, 6, 12 as part of an alternating protocol.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Routes of administration
Contraindications
- Known hypersensitivity
- Pre-existing bone marrow suppression
- Liver dysfunction
- Known pulmonary disease
- Susceptibility to pulmonary fibrosis
Adverse effects
- Myelosuppression
- Gastrointestinal adverse events (including haemorrhagic gastroenteritis)
- Liver enzyme activity elevation
- Azotaemia
- Fever
- Weight loss
- Lethargy
- Dermatological signs
- Pulmonary fibrosis
- Injected sclera
- Urinary signs (proteinuria, glycosuria)
Monitoring
- Complete Blood Count (CBC) for myelosuppression
- Liver enzyme activity
- Renal parameters (BUN, Creatinine) and Urinalysis (for proteinuria/glycosuria)
- Respiratory rate and effort (monitor for pulmonary fibrosis)
- Clinical signs of gastrointestinal toxicity
Overdose
Information not provided in the monograph. Due to its cytotoxic nature, overdose is likely to cause severe myelosuppression, gastrointestinal toxicity, and potentially fatal pulmonary fibrosis. Aggressive supportive care and monitoring are indicated.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.