Regular proteinuria monitoring significant during masitinib treatment, study finds
The study suggets that a urine protein: creatinine greater than 0.5 should prompt reassessment within one week.
Weekly proteinuria monitoring is useful in the first month of masitinib treatment for dogs with neoplasia, a recent study has found.
Published in the Journal of Small Animal Practice (JSAP), the study 'Development and progression of proteinuria in dogs treated with masitinib for neoplasia: 28 cases (2010 – 2019)' retrospectively evaluated the medical records of 28 dogs treated with masitnib for neoplasia.
Using data such as dosage, changes to medication administration or dosing, presence of gross disease and haematology and biochemistry profile results, urinalysis and urine cultures, the study investigated the development of proteinuria to allows for better informed recommendations on how to monitor and manage proteinuria.
Of the 28 dogs included in the study, five were undergoing treatment for epitheliotropic lymphoma, two for vuval lymphoma and malignant melanoma respectively, and 21 for mast cell tumours. Of these dogs, 22 were non-proteinuric, four developed proteinuria within one month of treatment beginning, and six were proteinuric at baseline.
Masitinib treatment was discontinued for three of the dogs with proteinuria before treatment due to lack of effectiveness, and three were euthanised during treatment.
Corresponding author for the paper, Dr Margaux Kuijlaars, commented: “Patients developing proteinuria should be investigated to exclude non-renal causes.
“This should allow for more informed recommendations on the monitoring and management of proteinuria and further masitinib treatment in these patients to be made. Masitinib treatment can be considered in patients with pre-treatment proteinuria and does not inevitably cause worsening of proteinuria.
“The findings of this study add to the evidence base for the use of masitinib in treating neoplasia in small animal patients. The use of masitinib in dogs in this study was off-licence as C-KIT MCT expression was not determined, and many dogs were treated for other tumours.”
JSAP editor Nicola Di Girolamo commented on the study: “Little is known about which dogs are predisposed to becoming proteinuric following treatment with masitinib for neoplasia. Due to the small number of dogs in this study that developed proteinuria, conclusions about predisposing factors cannot be definitely drawn.
“The findings of this study add to the evidence base and demonstrate the need for larger, prospective trials including a control population and longer period of follow-up.”
The paper is free to access and can be found here.
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