Continuous streptozotocin infusion: a phase I study

Area of Science:

• Oncology
• Pharmacology

Background:

• Streptozotocin (STZ) exhibits antitumor properties but is limited by renal and gastrointestinal toxicity.
• Continuous infusion strategies may mitigate STZ's adverse effects.

Purpose of the Study:

• To evaluate the safety and efficacy of prolonged continuous intravenous infusions of streptozotocin in patients with advanced cancers.
• To assess renal, gastrointestinal, and central nervous system toxicity associated with this administration method.

Main Methods:

• Nineteen patients with advanced cancers received streptozotocin (STZ) at 3.4 g/m2 via continuous IV infusion over 5-6 days monthly for 1-2 cycles.
• Pre- and post-treatment serum and urine studies were conducted.
• Adverse events, including renal function, proteinuria, myelosuppression, gastrointestinal symptoms, and neurological effects, were monitored.

Main Results:

• No significant changes in BUN or creatinine were observed, indicating preserved renal function.
• Proteinuria developed in four patients, but no renal failure or myelosuppression occurred.
• Gastrointestinal toxicity (nausea/vomiting) was reported in 13 patients, with varying severity and control.
• Five patients experienced central nervous system toxicity (confusion, lethargy, depression).
• Two patients achieved complete remission of diffuse non-Hodgkin's lymphoma; others showed documented improvement.

Conclusions:

• Prolonged continuous intravenous streptozotocin infusions demonstrate potential clinical promise for advanced cancers.
• While renal and gastrointestinal toxicities appear manageable, central nervous system toxicity may be a dose-limiting factor.
• Further investigation into optimizing STZ infusion protocols is warranted.