Purpose: S-CKD602 is a STEALTH liposomal formulation of CKD-602, a camptothecin analogue. The cytotoxicity of camptothecin analogues is related to the duration of exposure in the tumor. STEALTH liposomal formulations contain lipid conjugated to methoxypolyethylene glycol and have been designed to prolong drug circulation time, increase tumor delivery, and improve the therapeutic index. For STEALTH liposomal formulations of anticancer agents to achieve antitumor effects, the active drug must be released into the tumor extracellular fluid (ECF). Experimental Design: S-CKD602 at 1 mg/kg or nonliposomal CKD-602 at 30 mg/kg was administered once via tail vein to mice bearing A375 human melanoma xenografts. Mice (n = 3 per time point) were euthanized at 0.083 to 24 h, 48 h, and 72 h after S-CKD02 and from 0.083 to 24 h after nonliposomal CKD-602. Plasma samples were processed to measure encapsulated, released, and sum total (encapsulated plus released) CKD-602, and tumor and tissue samples were processed to measure sum total CKD-602. Microdialysis samples of tumor ECF were obtained from 0 to 2 h, 4 to 7 h, and 20 to 24 h after nonliposomal CKD-602 and from 0 to 2 h, 24 to 27 h, 48 to 51 h, and 72 to 75 h after S-CKD602. A liquid chromatographymass spectrometry assay was used to measure the total (sum of lactone and hydroxyl acid) CKD-602. The area under the concentration-versus-time curves (AUC) from 0 to infinity and time >1ng/mL in tumor were estimated.Results: For S-CKD602, the CKD-602 sum total AUC in plasma and tumor and the CKD-602 AUC in tumor ECF were 201,929, 13,194, and 187 ng/mL h, respectively. For S-CKD602, 82% of CKD-602 remains encapsulated in plasma. For nonliposomal CKD-602, the CKD-602 AUC in plasma and tumor and the CKD-602 AUC in tumor ECF were 9,117, 11,661, and 639 ng/mL Á h, respectively. The duration of time the CKD-602 concentration was >1ng/mL in tumor ECF after S-CKD602 and nonliposomal CKD-602 was >72 and f20 h, respectively. For S-CKD602, the CKD-602 sum total exposure was 1.3-fold higher in fat as compared with muscle. The ratio of CKD-602 sum total exposure in fat to muscle was 3.8-fold higher after administration of S-CKD602 compared with nonliposomal CKD-602. Conclusion: S-CKD602 provides pharmacokinetic advantages in plasma, tumor, and tumor ECF compared with nonliposomal CKD-602 at 1/30th of the dose, which is consistent with the improved antitumor efficacy of S-CKD602 in preclinical studies. The distribution of S-CKD602 is greater in fat compared with muscle whereas the distribution of nonliposomal CKD-602 is greater in muscle compared with fat.These results suggest that the body composition of a patient may affect the disposition of S-CKD602 and released CKD-602.

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S-CKD602 is a pegylated liposomal formulation of CKD-602. This study is the first to evaluate the factors affecting the high interpatient variability in the pharmacokinetic disposition of S-CKD602. S-CKD602 was administered intravenously (i.v.) every 3 weeks as part of a phase I study. Pharmacokinetics studies of the liposomal encapsulated and released CKD-602 in plasma were performed. The pharmacokinetic variability of S-CKD602 is associated with both linear and nonlinear clearances. Patients > or =60 years of age have a 2.7-fold higher exposure of S-CKD602 as compared with patients <60 years of age (P = 0.02). Patients with a lean body composition have a higher plasma exposure of S-CKD602 (P = 0.02). Patients who have received prior therapy with pegylated liposomal doxorubicin (PLD) have a 2.2-fold higher exposure of S-CKD602 as compared with patients who have not received PLD (P = 0.045). Prolonged exposure of the encapsulated drug in plasma over 1-2 weeks provides significant pharmacologic advantages. The high interpatient variability in the pharmacokinetic disposition of S-CKD602 was associated with age, body composition, saturable clearance, and prior PLD therapy.

Cloves (Syzygium aromaticum) have been used as a traditional Chinese medicinal herb for thousands of years. Cloves possess antiseptic, antibacterial, antifungal, and antiviral properties, but their potential anticancer activity remains unknown. In this study, we investigated the in vitro and in vivo antitumor effects and biological mechanisms of ethyl acetate extract of cloves (EAEC) and the potential bioactive components responsible for its antitumor activity. The effects of EAEC on cell growth, cell cycle distribution, and apoptosis were investigated using human cancer cell lines. The molecular changes associated with the effects of EAEC were analyzed by Western blot and (qRT)-PCR analysis. The in vivo effect of EAEC and its bioactive component was investigated using the HT-29 tumor xenograft model. We identified oleanolic acid (OA) as one of the components of EAEC responsible for its antitumor activity. Both EAEC and OA display cytotoxicity against several human cancer cell lines. Interestingly, EAEC was superior to OA and the chemotherapeutic agent 5-fluorouracil at suppressing growth of colon tumor xenografts. EAEC promoted G0/G1 cell cycle arrest and induced apoptosis in a dose-dependent manner. Treatment with EAEC and OA selectively increased protein expression of p21WAF1/Cip1 and γ-H2AX and downregulated expression of cell cycle-regulated proteins. Moreover, many of these changes were at the mRNA level, suggesting transcriptional regulation by EAEC treatment. Our results demonstrate that clove extract may represent a novel therapeutic herb for the treatment of colorectal cancer, and OA appears to be one of the bioactive components.

Monocytes are more sensitive to S-CKD602, compared with neutrophils, and the increased sensitivity is related to the liposomal formulation, not CKD-602. These results suggest that monocytes engulf S-CKD602, which causes the release of CKD-602 from the liposome and toxicity to the monocytes, and that the effects are more prominent in patients <60.

PURPOSE Cisplatin is synergistic with vinorelbine and the poly(ADP-ribose) polymerase (PARP) inhibitor veliparib, and has anti-neoplastic activity in TNBC and BRCA mutation-associated breast cancer. This phase I study assessed veliparib with cisplatin and vinorelbine. PATIENTS AND METHODS A 3+3 dose escalation design evaluated veliparib administered BID for 14 days with cisplatin (75 mg/m2 day 1) and vinorelbine (25 mg/m2 days 1,8) every 21 days, for six to ten cycles, followed by veliparib monotherapy. Pharmacokinetics, measurement of poly(ADP-ribose) in peripheral blood mononuclear cells, and preliminary efficacy were assessed. Immunohistochemistry and gene expression profiling were evaluated as potential predictors of response. RESULTS Forty-five patients enrolled in nine dose cohorts plus five in an expansion cohort at the highest dose level and recommended phase II dose, 300 mg BID. Maximum tolerated dose of veliparib was not reached. Neutropenia (36%), anemia (30%), and thrombocytopenia (12%) were the most common grade 3/4 adverse events. Best overall response for 48 patients was radiologic response with 9-week confirmation for 17 (35%; 2 complete, 15 partial), and stable disease for 21 (44%). Germline BRCA mutation presence versus absence was associated with 6-month progression-free survival (10 of 14 (71%) vs 8 of 27 (30%), mid-p=0.01). Median progression-free survival for all 50 patients was 5.5 months (95% confidence interval 4.1–6.7). CONCLUSION Veliparib at 300 mg BID combined with cisplatin and vinorelbine is well tolerated with encouraging response rates. A phase II randomized trial is planned to assess veliparib’s contribution to cisplatin chemotherapy in metastatic TNBC and BRCA mutation-associated breast cancer. Translational Relevance We hypothesize that TNBC tumors have defects in homologous recombination DNA repair similar to BRCA mutation associated tumors, which will render them sensitive to platinum therapy and PARP inhibition. This report describes a phase I study that explored the safety and efficacy of cisplatin, vinorelbine and veliparib. This combination was tolerable and reached the highest dose of veliparib in combination with chemotherapy used in breast cancer to date. Antineoplastic activity was observed both in BRCA mutation associated breast cancer and in BRCA wild-type TNBC. We measured changes in PARP activity and performed gene expression profiling and immunohistochemistry studies. Based on promising results from this study, a randomized phase II study has been developed to evaluate the addition of veliparib to cisplatin chemotherapy for patients with advanced TNBC. This study will incorporate a multi-pronged biomarker approach to identify a homologous recombination repair deficiency (HRD) phenotype that derives benefit from PARP inhibition.

Purpose: S-CKD602 is a pegylated liposomal formulation of CKD602, a semisynthetic camptothecin analogue. Pegylated (STEALTH) liposomes can achieve extended drug exposure in plasma and tumor. Based on promising preclinical data, the first phase I study of S-CKD602 was done in patients with refractory solid tumors. Experimental Design: S-CKD602 was administered i.v. every 3 weeks. Modified Fibonacci escalation was used (three to six patients/cohort), and dose levels ranged from 0.1to 2.5 mg/m 2 . Serial plasma samples were obtained over 2 weeks and total (lactone + hydroxyl acid) concentrations of encapsulated, released, and sum total (encapsulated + released) CKD602 measured by liquid chromatography-tandem mass spectrometry. Results: Forty-five patients (21males) were treated. Median age, 62 years (range, 33-79 years) and Eastern Cooperative Oncology Group status, 0 to 1 (43 patients) and 2 (2 patients). Dose-limiting toxicities of grade 3 mucositis occurred in one of six patients at 0.3 mg/m 2 , grade 3 and 4 bone marrow suppression in two of three patients at 2.5 mg/m 2 , and grade 3 febrile neutropenia and anemia in one of six patients at 2.1 mg/m 2 . The maximum tolerated dose was 2.1 mg/m 2 . Partial responses occurredin two patients with refractory ovarian cancer (1.7 and 2.1mg/m 2 ). Highinterpatient variability occurred in the pharmacokinetic disposition of encapsulated and released CKD602. Conclusions: S-CKD602 represents a promising new liposomal camptothecin analogue with manageable toxicity and promising antitumor activity. Phase II studies of S-CKD602 at 2.1mg/m 2 i.v. once every 3 weeks are planned. Prolonged plasma exposure over 1to 2 weeks is consistent with STEALTH liposomes and provides extended exposure compared with single doses of nonliposomal camptothecins.

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