[LY188011 phase I study. Research Group of Gemcitabine (LY188011)]

LY188011 (Gemcitabine hydrochloride) is a new derivative of deoxycytidine. Phase I study was carried out by a cooperative study group. LY188011 was administered weekly for 3 consecutive weeks starting with an initial dose of 60 mg/m2 (1n) and then increasing the dosage to 1,000 mg/m2 (16.7n). Dose limiting factor was found to be myelosuppression (decreases of WBC, neutrophils and platelet), and MTD was considered to be 1,000 mg/m2. The nadir of WBC and platelet were observed after about 1-3 weeks. It took 1-2 weeks for their recovery. Other adverse reactions included fever, fatigue, anorexia, nausea/vomiting, anemia and transient elevations of GOT and GPT. However, those adverse reactions were mild. T1/2 rho of plasma concentration was about 19 min and the C5min was dependent on the dose. Anti-cancer effects were observed in one gastric cancer and two colon cancer patients. It is recommended that the dosing schedule for an early phase II study is 800 mg/m2 weekly for 3 weeks with 1 week of rest as one cycle, in multiple cycles.