As part of our continuing work to obtain new pro-drugs for the treatment of nephropathic cystinosis, a number of glutaric and succinic acid derivatives of cystamine have been designed, synthesised and biologically evaluated in vitro. These compounds have been designed as odourless and tasteless pro-drugs which will release multiple molecules of cysteamine upon administration. All of the synthesised compounds evaluated in this study were non-cytotoxic and displayed a greater ability than cysteamine to deplete the levels of cystine in cultured fibroblasts.