EVALUATION OF NEW BENZOPORPHYRIN DERIVATIVES WITH ENHANCED PDT EFFICACY

A first report on the biological evaluation of a series of isomericall y pure benzoporphyrin derivatives (cis- and trans-isomers) as methyl e sters is described. In preliminary in vivo studies, the n-hexyl ether analogues of both cis- and trans-isomers of benzoporphyrin derivatives were found to be more active than the industrially prepared benzoporp hyrin derivative, a mixture of monocarboxylic acids (BPDMA, Quadralogi c Technologies, Vancouver). Further studies with 4-de-vinyl-4-(1-hexyl oxyethyl) benzoporphyrin derivative showed that, like BPDMA, it had re duced residual skin phototoxicity compared in mice with Photofrin(R). The uptake and clearance characteristics of BPDMA were also compared w ith the 4-(1-hexyloxyethyl)-derivative by in vivo reflection spectrosc opy.