Zeniplatin in advanced malignant melanoma and renal cancer: phase II studies with unexpected nephrotoxicity

The status of platinum anticancer drugs in the clinic and in clinical trials

Since its approval in 1979 cisplatin has become an important component in chemotherapy regimes for the treatment of ovarian, testicular, lung and bladder cancers, as well as lymphomas, myelomas and melanoma. Unfortunately its continued use is greatly limited by severe dose limiting side effects and intrinsic or acquired drug resistance. Over the last 30 years, 23 other platinum-based drugs have entered clinical trials with only two (carboplatin and oxaliplatin) of these gaining international marketing approval, and another three (nedaplatin, lobaplatin and heptaplatin) gaining approval in individual nations. During this time there have been more failures than successes with the development of 14 drugs being halted during clinical trials. Currently there are four drugs in the various phases of clinical trial (satraplatin, picoplatin, Lipoplatin and ProLindac). No new small molecule platinum drug has entered clinical trials since 1999 which is representative of a shift in focus away from drug design and towards drug delivery in the last decade. In this perspective article we update the status of platinum anticancer drugs currently approved for use, those undergoing clinical trials and those discontinued during clinical trials, and discuss the results in the context of where we believe the field will develop over the next decade.

The development of platinum compounds and their possible combination

Cisplatin plays a central role in cancer chemotherapy in spite of its toxicity. To circumvent this toxicity and to enhance its therapeutic index a lot of preclinical and clinical studies have been conducted and several thousand analogues have been synthesized. Much more analysis remains to be done, but nowadays, the absence of any definitive, biologically interpretable molecular predictor of activity is consistent with the idea that platinum compounds have multiple intracellular targets and that cells can have multiple mechanisms of resistance. This review analyses a part of these platinum compounds analyzed to date, their mechanism of action, resistance and the future trends in this sector.

Oxaliplatin-related neurotoxicity: how and why?

In early clinical trials, oxaliplatin has demonstrated significant activity against colorectal cancer in combination with 5-fluorouracil (5-FU) and folinic acid (FA), both in metastatic as in radically resected disease. The drug differs from the other two most important platinum compounds (cisplatin and carboplatin) for the absence of nephrotoxicity or for the reduced drug-induced ototoxicity. During its administration, two different types of neurological symptoms can be experienced: the first one occurs during or immediately after the end of the infusion and it appears as a transient peripheral sensory neuropathy manifesting as paresthesias and dysesthesia in the extremities sometimes accompanied by muscular contractions of the extremities or the jaw (triggered or enhanced by exposure to cold). The second one occurs after long-term administration of oxaliplatin presenting with deep sensory loss, sensory ataxia and functional impairment (similar to those observed with cisplatin). This type of neurotoxicity is usually late-onset and correlated with the cumulative-dose of oxaliplatin. The aim of this review is to analyse the mechanism underlying induction of neurotoxicity and the possible treatments to prevent and to treat it.

Medical management of melanoma

The treatment for malignant melanoma has undergone significant changes over the past few decades, with biological therapy playing an increasingly important role and replacing the traditional cytotoxic agents as the first-line therapy for this disease, both in advanced disease and adjuvant settings. Despite the developments of new modalities of therapy for melanoma, the outcome for patients with advanced disease remains poor. This article discusses the clinical studies that have shaped our current management of melanoma, both in the adjuvant setting, and in the metastatic setting. Additionally, successes and failures of clinical trials will be discussed, as they will guide the strategic development of future studies in the management of this aggressive disease.

A phase II study of Irofulven (MGI 114) in patients with stage IV melanoma

Sixteen patients with stage IV melanoma, who were heavily pretreated, received 11 mg/m2/day of intravenous Irofulven for five consecutive days every 28 days. There were no objective tumor responses, although one patient exhibited stable disease after 4 cycles. The most common toxicities were grade 1/2 nausea, vomiting, fatigue, anemia, and thrombocytopenia. One patient required a dose reduction for an elevated creatinine while another patient required cessation of treatment because of acute ataxia that may have been related to Irofulven. Based upon these data, Irofulven does not demonstrate significant antitumor activity to warrant further investigation in advanced melanoma.