Platinum compounds oral activity

Pt(TV) Prodrugs. Platinum(IV) complexes have been widely studied as potential prodrugs that avoid the limitations of the cisplatin class of anticancer drugs. Indeed, the Pt(IV) compound satraplatin [Pt(cha)Cl2(OAc)2(NH3)] (cha, cyclohexylamine) is currently in clinical trials for treatment of hormone-refractory prostate cancer (Fig. 1) (22). Satraplatin is the first orally bioavailable platinum derivative under active clinical investigation and is particularly attractive because of the convenience of administration, milder toxicity profile, and lack of cross-resistance with cisplatin. These results are promising and support the idea that platinum(IV) complexes offer the opportunity to overcome some of the problems associated with cisplatin and its analogs. 

At the preclinical level, oral antitumor activity has been observed with two other classes of platinum compound, the PtIV monocarboxylate, C(5)-OHP-C1, and the first Ptn complex to exhibit oral activity, the sterically hindered AMD473. Now licenced to Zeneca, AMD473 exhibited promising circumvention of acquired cisplatin resistance against both in vitro and in vivo preclinical models. Together with the drug s favourable pharmacokinetic and toxicology profile in rodents (myelosuppression was dose-limit-... 

The success of cisplatin and carboplatin in treating cancer, combined with the intrinsic and acquired resistance of many tumors to traditional platinum chemotherapy, has generated considerable interest in developing next-generation platinum drugs. Since the discovery of the antitumor activity of cisplatin, researchers have reported the synthesis, characterization, and antitumor activity of thousands of platinum compounds [1] [2]. The previous two chapters in this section describe the promising activity of novel multi-nuclear Ptn and orally active PtIV complexes [3] [4],... 

After intravenous or oral administration of the drug, it undergoes several biotransformations that activate its toxicity (tumor cells as well as nephro- and neurotoxicity). A number of speciation studies that focused on characterization and quantification of parent drug and its possible metabohtes in vitro and in vivo have been reported. Element-specific ICP-MS detection has been applied after LC separation of platinum compounds. In Figure 6, the LC-ICP-MS chromatogram is presented, and this was obtained for the mixture of cancerostatic platinum compounds. ... 

Figure 3.117 (a) JM-216, a platinum(IV) compound under clinical tests as an orally administered anti-tumour agent (b) the platinum(II) product of in vivo reduction, likely to be the active... 

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