Phase I study of green tea extract in patients with advanced lung cancer

Epidemiologic studies suggest that consumption of green tea may have a protective effect against the development of several cancers. Preclinical studies of green tea and its polyphenolic components have demonstrated antimutagenic and anticarcinogenic activity, and inhibition of growth of tumor cell lines and animal tumor models, including lung cancer. Green tea may also have chemopreventive properties, and enhancement of cytotoxicity of chemotherapeutic agents has been demonstrated. This trial was designed to determine the maximum tolerated dose (MTD) of green tea extract (GTE) in patients with advanced lung cancer.

A total of 17 patients with advanced lung cancer were registered to receive once-daily oral dosing of GTE at a starting dose of 0.5 g/m2 per day, with an accelerated dose-escalation scheme.

On this schedule, the MTD of GTE was 3 g/m2 per day, and at this dose, GTE was well tolerated with no grade 3 or 4 toxicity seen. Dose-limiting toxicities were diarrhea, nausea and hypertension. No objective responses were seen in this trial. Seven patients had stable disease ranging from 4 to 16 weeks; no patient remained on therapy longer than 16 weeks due to the development of progressive disease.

This study suggests that while relatively nontoxic at a dose of 3 g/m2 per day, GTE likely has limited activity as a cytotoxic agent, and further study of GTE as a single-agent in established malignancies may not be warranted. Further studies should focus on the potential chemopreventive and chemotherapy-enhancing properties of GTE.