Cancer Therapy : Clinical Phase I Studies of CBP 501 , a G 2 Checkpoint Abrogator , as Monotherapy and in Combination with Cisplatin in Patients with Advanced Solid Tumors

Purpose: Two phase I dose-escalation studies were conducted to determine themaximum tolerated dose (MTD) and safety profile of the G2 checkpoint abrogator CBP501, as a single agent and in combination with cisplatin. Experimental Design: Patients with advanced solid tumors were treated with CBP501 alone (D1/D8/ D15, q4w, from 0.9 mg/m), or with cisplatin (both on D1, q3w, from 3.6 mg/m CBP501, 50 mg/m cisplatin). Dose escalation proceeded if dose-limiting toxicity (DLT) was observed in 1 or less of 3 to 6 patients; CBP501 dose increments were implemented according to the incidence of toxicity. MTD was determined from DLTs occurring during the first two cycles. Results: In the combination study, the DLT was a histamine-release syndrome (HRS) occurring 10 to 60 minutes after initiating infusion that was attenuated by prophylaxis comprising dexamethasone, diphenhydramine, ranitidine, and loratadine. The MTDwas 25mg/m CBP501 and 75mg/m cisplatin, with two patients at the highest dose (36.4mg/m CBP501, 75mg/m cisplatin) experiencing grade 3 HRS. The only DLT with monotherapy was transient G3 rise of troponin in one patient. Grade 3 to 4 treatment–related events were rare. Promising activity was observed with CBP501/cisplatin, mainly in ovarian and mesothelioma patients who had previously progressed on platinum-containing regimens. Among ovarian cancer patients, low expression of DNA repair proteins was associated with partial response or stable disease. Conclusions: CBP501 is well tolerated in patients as monotherapy and with cisplatin. At the recommended phase II dose (RP2D), the combination is feasible and HRS manageable with prophylaxis. Evidence of antitumor activity was observed in platinum-resistant patients. Clin Cancer Res; 17(10); 3431–42. 2011 AACR.

[1]  M. Ellis,et al.  A Phase 1 study of UCN-01 in combination with irinotecan in patients with resistant solid tumor malignancies , 2010, Cancer Chemotherapy and Pharmacology.

[2]  O. Schärer,et al.  Translesion DNA synthesis polymerases in DNA interstrand crosslink repair , 2010, Environmental and molecular mutagenesis.

[3]  J. Rahn,et al.  Multiple roles of ERCC1‐XPF in mammalian interstrand crosslink repair , 2010, Environmental and molecular mutagenesis.

[4]  S. Ahmad Platinum—DNA Interactions and Subsequent Cellular Processes Controlling Sensitivity to Anticancer Platinum Complexes , 2010 .

[5]  Yun Dai,et al.  New Insights into Checkpoint Kinase 1 in the DNA Damage Response Signaling Network , 2010, Clinical Cancer Research.

[6]  G. Shapiro,et al.  Abstract B47: CBP501, a novel cell cycle dysregulator, in combination with cisplatin (CDDP) and pemetrexed (PM) ‐ results of two phase I/II studies , 2009 .

[7]  G. Shapiro,et al.  Abstract C131: CBP501 (CBP), a novel cell cycle dysregulator, in combination with cisplatin (CDDP) and pemetrexed (PM) ‐ pharmacokinetics (PK) in two phase I/II studies , 2009 .

[8]  T. Chou,et al.  90-kDa Heat Shock Protein Inhibition Abrogates the Topoisomerase I Poison-Induced G2/M Checkpoint in p53-Null Tumor Cells by Depleting Chk1 and Wee1 , 2009, Molecular Pharmacology.

[9]  M. Gonen,et al.  A Phase 1 Dose-Escalation Study of Irinotecan in Combination with 17-Allylamino-17-Demethoxygeldanamycin in Patients with Solid Tumors , 2008, Clinical Cancer Research.

[10]  B. Karlan,et al.  Secondary BRCA1 mutations in BRCA1-mutated ovarian carcinomas with platinum resistance. , 2008, Cancer research.

[11]  T. Hamilton,et al.  Platinum Resistance: The Role of DNA Repair Pathways , 2008, Clinical Cancer Research.

[12]  A. Jimeno,et al.  Phase I and pharmacokinetic study of UCN-01 in combination with irinotecan in patients with solid tumors , 2008, Cancer Chemotherapy and Pharmacology.

[13]  C. Britten,et al.  G2 checkpoint abrogation and checkpoint kinase-1 targeting in the treatment of cancer , 2008, British Journal of Cancer.

[14]  Hidetaka Kobayashi,et al.  Cell cycle phenotype-based optimization of G2-abrogating peptides yields CBP501 with a unique mechanism of action at the G2 checkpoint , 2007, Molecular Cancer Therapeutics.

[15]  M. Ernstoff,et al.  Modulation of Cell Cycle Progression in Human Tumors: A Pharmacokinetic and Tumor Molecular Pharmacodynamic Study of Cisplatin Plus the Chk1 Inhibitor UCN-01 (NSC 638850) , 2006, Clinical Cancer Research.

[16]  G. Shapiro,et al.  346 POSTER CBP501, a novel cell cycle G2 checkpoint abrogator. Preliminary results of the initial phase I and pharmacokinetic (PK)/pharmacodynamic (PD) study in patients (pts) with advanced solid tumors , 2006 .

[17]  A. D’Andrea,et al.  DNA repair pathways in clinical practice: lessons from pediatric cancer susceptibility syndromes. , 2006, Journal of clinical oncology : official journal of the American Society of Clinical Oncology.

[18]  J. Doroshow,et al.  The Cyclin-Dependent Kinase Inhibitor UCN-01 Plus Cisplatin in Advanced Solid Tumors: A California Cancer Consortium Phase I Pharmacokinetic and Molecular Correlative Trial , 2005, Clinical Cancer Research.

[19]  S. Davidson,et al.  A phase I and pharmacokinetic study of short infusions of UCN-01 in patients with refractory solid tumors. , 2005, Clinical cancer research : an official journal of the American Association for Cancer Research.

[20]  Michael B Yaffe,et al.  MAPKAP kinase-2 is a cell cycle checkpoint kinase that regulates the G2/M transition and S phase progression in response to UV irradiation. , 2005, Molecular cell.

[21]  Sonnet J. H. Arlander,et al.  Hsp90 Inhibition Depletes Chk1 and Sensitizes Tumor Cells to Replication Stress* , 2003, Journal of Biological Chemistry.

[22]  Jiri Bartek,et al.  Chk1 and Chk2 kinases in checkpoint control and cancer. , 2003, Cancer cell.

[23]  R. Kanaar,et al.  Repair of DNA interstrand cross-links. , 2001, Mutation research.

[24]  R. Abraham Cell cycle checkpoint signaling through the ATM and ATR kinases. , 2001, Genes & development.

[25]  E. Sausville,et al.  Phase I trial of 72-hour continuous infusion UCN-01 in patients with refractory neoplasms. , 2001, Journal of clinical oncology : official journal of the American Society of Clinical Oncology.

[26]  J. Sarkaria,et al.  The radiosensitizing agent 7-hydroxystaurosporine (UCN-01) inhibits the DNA damage checkpoint kinase hChk1. , 2000, Cancer research.

[27]  Edward A. Sausville,et al.  The Chk1 Protein Kinase and the Cdc25C Regulatory Pathways Are Targets of the Anticancer Agent UCN-01* , 2000, The Journal of Biological Chemistry.

[28]  J. Harper,et al.  Anticancer drug targets: cell cycle and checkpoint control. , 1999, The Journal of clinical investigation.

[29]  J. Sarkaria,et al.  Inhibition of ATM and ATR kinase activities by the radiosensitizing agent, caffeine. , 1999, Cancer research.

[30]  C. Peng,et al.  C-TAK1 protein kinase phosphorylates human Cdc25C on serine 216 and promotes 14-3-3 protein binding. , 1998, Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research.

[31]  K. Kohn,et al.  Abrogation of an S-phase checkpoint and potentiation of camptothecin cytotoxicity by 7-hydroxystaurosporine (UCN-01) in human cancer cell lines, possibly influenced by p53 function. , 1997, Cancer research.

[32]  N. Rhind,et al.  Cdc25 mitotic inducer targeted by chk1 DNA damage checkpoint kinase. , 1997, Science.

[33]  C. Peng,et al.  Mitotic and G2 checkpoint control: regulation of 14-3-3 protein binding by phosphorylation of Cdc25C on serine-216. , 1997, Science.

[34]  C. Sherr Cancer Cell Cycles , 1996, Science.

[35]  E. Sausville,et al.  UCN-01: a potent abrogator of G2 checkpoint function in cancer cells with disrupted p53. , 1996, Journal of the National Cancer Institute.

[36]  L. Hartwell,et al.  Cell cycle control and cancer. , 1994, Science.

[37]  A. Pardee,et al.  Mechanism by which caffeine potentiates lethality of nitrogen mustard. , 1982, Proceedings of the National Academy of Sciences of the United States of America.

[38]  P. Roy,et al.  Further studies on histamine release from rat mast cells in vitro induced by peptides. Characteristics of a synthetic intermediate with potent releasing activity. , 1980, The Biochemical journal.

[39]  B. Mackler,et al.  Further studies on the structural requirements for polypeptide-mediated histamine release from rat mast cells. , 1979, The Biochemical journal.