Clinical uses of pegylated pharmaceuticals in oncology.

A number of agents that are used in the treatment of cancer have a suboptimal pharmacokinetic profile that necessitates prolonged or repetitive administration. Pegylation of these agents may help overcome these shortcomings without compromising the agents' efficacy. Several such pegylated agents have now been developed and evaluated in patients with oncology-related disorders. Pegfilgrastim (a pegylated form of filgrastim) has shown efficacy and tolerability that are at least equivalent to those of filgrastim in patients with chemotherapy-induced neutropenia and, unlike unmodified filgrastim, is effective with only one administration per chemotherapy cycle. Other promising pegylated agents are pegylated liposomal doxorubicin, which appears to be more effective and less cardiotoxic than unmodified or liposome-encapsulated doxorubicin, and peginterferon alpha-2a, as once-weekly treatment for renal cell carcinoma. Pegylated agents are likely to be more convenient for patients than the standard formulations, and the improved pharmacokinetics will enhance the clinical utility of these agents.