TOXICOLOGIC PROFILE OF IOBITRIDOL, A NEW NONIONIC LOW-OSMOLALITY CONTRAST-MEDIUM

Purpose: The toxicologic profile of iobitridol, a new nonionic low-osm olality contrast medium, was evaluated in compliance with the current regulatory requirements in Europe, the USA and Canada. Material and Me thods: The toxicity of iobitridol was tested following acute or repeat ed i.v. administration in several different species (mouse, rat, dog); single oral administration in the mouse and intracisternal injection in the rat. Furthermore, teratogenicity and mutagenicity were evaluate d in the rat and rabbit. Local perivenous toxicity was assessed in the rabbit. Results: The acute toxicity of iobitridol in the mouse is equ ivalent to that of iohexol, a reference product tested under the same conditions. Chronic administration (daily i.v. injection over 4 weeks) in the rat and dog did not demonstrate any particular toxicity for io bitridol. It should be noted that, unlike iohexol, iobitridol did not provoke any vacuolization of the renal tubular cells in the rat follow ing repeated injections, Furthermore, this contrast agent did not show any teratogenic or mutagenic potential. The typical local inflammator y signs observed following perivenous injection in the rabbit were low in intensity and reversible. Conclusion: The toxicologic profile of i obitridol appears to be favorable and does not show any particular ris k for clinical use under the usual indications of water-soluble iodina ted contrast agents.