Comparison of Compounded, Generic, and Innovator-Formulated Itraconazole in Dogs and Cats

Abstract

The triazole antifungal itraconazole may be cost prohibitive in brand name form; therefore, compounded and generic products are often used as alternatives. Itraconazole blood concentrations have not been studied in clinical patients receiving these formulations. Itraconazole bioassay was performed on serum/plasma from 95 dogs and 20 cats receiving itraconazole (compounded from bulk powder, generic pelletized, or brand name) for systemic mycosis treatment. Mean itraconazole concentration was lower in the compounded group (n = 42) as compared with the generic (n = 40) or brand name (n = 33) groups (0.5 µg/mL versus 8.3 µg/mL and 6.5 µg/mL, respectively; P < .001). No statistical difference was observed between itraconazole concentrations in the generic and brand name groups. Forty animals (95.2%) in the compounded group had subtherapeutic (<1.0 µg/mL) values. All cats in this group (n = 10) had undetectable itraconazole concentrations. Some animals in the generic and brand name groups had subtherapeutic values (12.5 and 12.1%, respectively) or potentially toxic values (>10 µg/mL; 37.5 and 24%, respectively). Compounded itraconazole should be avoided, but generic itraconazole appears to serve as a reasonable alternative to brand name itraconazole. Therapeutic drug monitoring may be beneficial in all cases.

Pharmacokinetics of a modified, compounded theophylline product in dogs

“…The MCT product was obtained from a well‐established, veterinary, compounding pharmacy that has been in business for over 38 years and is one of the largest compounding pharmacies in the United States (About Wedgewood Custom Compounding Pharmacy, n.d.). High standards are maintained in accordance with United States Pharmacopeia chapters 795 and 797 and only FDA‐registered active pharmaceutical ingredient suppliers are used (Choosing a Compounding Pharmacy, n.d.); however, compounding is still a potential source of variability (Cook, Nieuwoudt, & Longhofer, ; Mawby, Whittemore, Genger, & Papich, ; Renschler, Albers, Sinclair‐Mackling, & Wheat, ). Despite these concerns, the MCT is reliably and consistently available to practitioners, unlike previously validated human products.…”

“…One limitation of our study is that the investigated product was compounded rather than commercially produced. The MCT product was obtained from a well-established, veterinary, compounding pharmacy that has been in business for over 38 years and is one of the largest compounding pharmacies in the United States (About ; however, compounding is still a potential source of variability (Cook, Nieuwoudt, & Longhofer, 2012;Mawby, Whittemore, Genger, & Papich, 2014;Renschler, Albers, Sinclair-Mackling, & Wheat, 2018). Despite these concerns, the MCT is reliably and consistently available to practitioners, unlike previously validated human prod-…”

Guideline for the management of feline sporotrichosis caused by Sporothrix brasiliensis and literature revision

“…Generic and compounded itraconazole are not bioequivalent to the reference drug. The use of compounded itraconazole is not recommended, but the generic is a satisfactory alternative to the reference drug [117,118].…”

Biology, diagnosis and treatment ofMalasseziadermatitis in dogs and cats Clinical Consensus Guidelines of the World Association for Veterinary Dermatology

“…In a similar study of eight healthy cats, itraconazole compounded in both capsules and suspension was absorbed poorly and inconsistently . In a field study of 95 dogs and 20 cats receiving either compounded, generic or innovator‐formulated itraconazole for systemic mycoses, sub‐therapeutic concentrations were detected in 95.2% of animals receiving the compounded formulation but in only 12.5% or less of the animals treated with generic or reference formulations . The poor bioavailability of itraconazole in compounded formulations and in some cases treatment failures, has been attributed to the absence of cyclodextrin, a carrier compound shown to improve gastro‐intestinal absorption .…”