VETERINARY USES OF RECOMBINANT HUMAN GRANULOCYTE-COLONY-STIMULATING FACTOR - PART I - ONCOLOGY

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) caus es an initial increase in leukocyte counts:in small animals. A subsequ ent decline in leukocyte count is attributed to the development-dt neu tralizing antibody to the rhG-CSF. According to the findings presented in this article, however, neutralizing antibodies against rhG-CSF did not develop in dogs or cats that received chemotherapy. Consequently, rhG-CSF might be useful for ameliorating chemotherapy-induced myelosu ppression in small animals, thus permitting more aggressive chemothera py protocols. Until further studies are completed, veterinarians shoul d avoid administering rhG-CSF within 24 hours before or after chemothe rapy. Giving the agent when neutrophil counts are less than,1000 cells /mu l is Sufficient to decrease the severity of myelosuppression. Shor t courses (three to six doses) may be sufficient to treat patients wit h severe myelosuppression. Long-term administration of rhG-CSF to norm al dogs and cats might lead to the formation of antibodies to endogeno us granolocyte colony-stimulating factor (G-CSF). Clients should be in formed about the cost of therapy (approximately $0.72/mu g) versus the potential risks of withholding therapy.The; true-risks of withholding G-CSF therapy from neutropenic animals will not be clear until contro lled randomized studies that involve tumor-bearing animals: are comple ted. the first part of this two-part article discusses the history of GL-CSF use in veterinary medicine and considers recommendations for ad ministering G-CSF to chemotherapy patients. Part II will deal with the use of G-CSF in patients with infectious disease, such as canine parv ovirus.