kw-2170 and Neoplasms

The primary purposes of this study were to determine the dose-limiting toxicity (DLT) and maximum tolerated dose (MTD), to recommend a dose for phase II studies, and to analyze the pharmacokinetics of KW-2170. A secondary purpose was to assess tumor response to KW-2170.. KW-2170 was given as a 30-min i.v. infusion every 4 weeks. Doses were escalated from 1.0 mg/m2 according to a modified Fibonacci method.. A total of 45 cycles of KW-2170 were delivered to 41 patients at doses ranging from 1.0 to 53.0 mg/m2. The primary DLT was neutropenia which was observed in two of six patients treated at 32.0 mg/m2 and in two of two patients treated at 53.0 mg/m2; therefore, the MTD was 53.0 mg/m2. Although no patients showed a complete response (CR)or partial response (PR), 15 patients were evaluated a shaving freedom from progression at the 1-month time-point, with two demonstrating slight tumor shrinkage in their metastatic lesions. None of the patients experienced significant cardiotoxicity. The plasma concentration of KW-2170 declined in a triphasic manner. The half-life, total clearance (CLtot) and volume of distribution (Vdss) were nearly constant and independent of dose, and showed a relatively small interpatient variability. A linear relationship was observed between dose and maximum plasma concentration (Cmax) and area under the concentration-time curve (AUC 0-infinity). In addition, there was a good correlation between neutropenia and AUC 0- infinity. This suggests that toxicity may be dependent on systemic exposure to the drug. Two oxi-dative metabolites were observed in the patients' plasma and urine.. The primary DLT of KW-2170 in this study was neutropenia, with a MTD of 53 mg/m2.A significant linear relationship was observed between neutropenia and AUC 0- infinity. We estimate the recommended dose for phase II studies to be 41.0 mg/m2.

Topics: Acridines; Adult; Aged; Antineoplastic Agents; Area Under Curve; Dose-Response Relationship, Drug; Female; Humans; Male; Middle Aged; Neoplasms; Pyrazoles

5-(3-Aminopropyl)amino-7,10-dihydroxy-2-(2-hydroxethyl)-aminoethyl -6H-pyrazolo[4,5,1-de]acridin-6-one dihydroxy-chloride (KW-2170), a novel derivative of pyrazoloacridone, was selected and evaluated for its antitumor activity and toxicity in mice. KW-2170 exhibited antitumor activity superior to adriamycin (ADM) against Sarcoma 180, breast carcinoma MM102 and fibrosarcoma Meth A inoculated s.c. in mice. Its therapeutic index (LD10/ED50) was higher than that of ADM on two murine carcinoma models, MM102 and Meth A. KW-2170 showed significant antitumor activity against 17 human tumor xenografts of a total of 24 tumors tested and the total tumor response rate by treatment with KW-2170 was significantly higher than that by ADM (70.8 versus 58.3%). In particular, human lung carcinoma was highly sensitive to KW-2170, and a marked tumor regression was observed on Lu-65 and Lu-99 human lung carcinoma xenograft models. Ovary and pancreas carcinomas were also sensitive to the drug. Additionally, its therapeutic index was also high on these human carcinoma models in comparison with that of ADM. The best antitumor efficacy of KW-2170 was observed by a weekly treatment schedule followed by a single treatment schedule and a successive administration schedule also tended to be toxic to the hosts. KW-2170 exhibited very low cross-resistance against four lines of multidrug resistant tumors expressing high levels of P-glycoprotein, and the drug showed significant antitumor activity against ADM-resistant human ovary carcinoma A2780/ADM and against nasopharynx carcinoma KB-A1 xenografts which were not sensitive to ADM. These results indicate that KW-2170 has a very potent antitumor activity and is feasible as a new antitumor drug against ADM-refractory solid tumors in clinics.

Topics: Acridines; Animals; Antineoplastic Agents; ATP Binding Cassette Transporter, Subfamily B, Member 1; Breast Neoplasms; Doxorubicin; Drug Resistance, Multiple; Female; Fibrosarcoma; Gastrointestinal Neoplasms; Humans; Liver Neoplasms; Lung Neoplasms; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Nude; Molecular Structure; Neoplasms; Prostatic Neoplasms; Pyrazoles; Sarcoma 180; Transplantation, Heterologous; Tumor Cells, Cultured