sjg-136 and Neoplasms

DNA-targeted chemotherapies remain fundamental in clinical management of both common solid tumours and hematologic malignancies. Recent studies indicate that novel combinations of cytotoxic chemotherapy may have significant activity even in tumours regarded as being resistant to conventional chemotherapy. In addition, the search for more selective and efficacious drugs that can deliver critical DNA damage with minimal side effects continues. Trabectedin, bendamustine and the pyrrolobenzodiazepine dimer SG2000 exemplify three different classes of DNA targeted agent undergoing clinical evaluation. Increasingly, DNA damaging drugs are being used in combination with novel agents such as small molecule inhibitors or antibodies targeting receptor tyrosine kinases. Understanding the mechanistic basis for interactions of these novel targeted agents with DNA-interactive drugs will inform design of optimal combinations for future studies and is critical to maximize benefit in the clinic.

Topics: Animals; Antineoplastic Agents, Alkylating; Antineoplastic Combined Chemotherapy Protocols; Bendamustine Hydrochloride; Benzodiazepinones; Dioxoles; DNA; DNA Damage; Humans; Neoplasms; Nitrogen Mustard Compounds; Pyrroles; Tetrahydroisoquinolines; Trabectedin

DNA interacting agents play a major role in cancer chemotherapy, either as single agents, in combination drug regimens, or as components of novel targeted therapies. The search for more selective and efficacious drugs that can deliver critical DNA damage with minimal side effects continues.. The development of the pyrrolobenzodiazepines (PBDs) from their discovery as natural products in the 1960s, through synthetic PBD monomers, PBD hybrids and conjugates, and PBD dimers is described. The latter molecules are capable of forming sequence selective, non-distorting and potently cytotoxic DNA interstrand cross-links in the minor groove of DNA. In particular, the development of PBD dimer SJG-136 (SG2000), currently in Phase II clinical trials, is presented. Potential future cancer therapeutic applications of PBDs, including their use as components of targeting strategies, are also discussed.. The culmination of over four decades of study on structure-activity relationships of PBDs has led to a detailed understanding of how to introduce structural modification to enhance biological activity and potency. The challenge for the next phase in the development of the PBDs is to harness this activity and potency in a new generation of cancer therapeutics.

Topics: Animals; Antineoplastic Agents; Benzodiazepines; Benzodiazepinones; DNA Damage; Drug Delivery Systems; Drug Design; Humans; Neoplasms; Pyrroles; Structure-Activity Relationship

This phase I study assessed the maximum tolerated dose (MTD), safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of SJG-136, a sequence-specific DNA cross-linking agent, in patients with advanced cancer.. In schedule A, seven patients received escalating doses of SJG-136 (6, 12, 24, and 48 μg/m(2)) daily for 5 of 21 days. Blood samples were collected for PK analysis on days 1 and 5 of cycle 1. In schedule B, SJG-136 was given daily for 3 of 21 days (N = 17; doses 20, 25, 30, and 35 μg/m(2)). Blood samples were collected on days 1 and 3 of cycles 1 and 2 for PK and PD analysis. Patients in schedule B received dexamethasone and early diuretic care.. Schedule A-dose-limiting toxicities included grade 3 edema, dyspnea, fatigue, and delayed liver toxicity (grade 3-4). PK analysis revealed dose-dependent increases in AUC and C(max). Substantial changes in volume of distribution at steady-state occurred after repeated dosing in some patients prior to the onset of edema. Schedule B-the same toxicities were manageable with steroid premedication and diuretic support. No significant myelosuppression occurred on either schedule. DNA interstrand cross-links correlated with systemic exposure of SJG-136 following the second dose in cycle 1 and were still detectable immediately before cycle 2.. The MTD of SJG-136 in this study was 30 μg/m(2) administered on a daily 3× basis with no myelosuppression effects. Coupled with supportive management, SJG-136 is now advancing to a phase II trial in ovarian cancer.

Topics: Adult; Aged; Aged, 80 and over; Benzodiazepinones; Dexamethasone; Dyspnea; Edema; Fatigue; Female; Humans; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Pyrroles

This phase I dose-escalation study was undertaken to establish the maximum tolerated dose of the sequence-selective minor groove DNA binding agent SJG-136 in patients with advanced solid tumors. The study also investigated antitumor activity and provided pharmacokinetic and pharmacodynamic data.. Sixteen patients were assigned sequentially to escalating doses of SJG-136 (15-240 microg/m(2)) given as a 10-minute i.v. infusion every 21 days. The dose was subsequently reduced in incremental steps to 45 microg/m(2) due to unexpected toxicity.. The maximum tolerated dose of SJG-136 was 45 microg/m(2). The main drug-related adverse event was vascular leak syndrome (VLS) characterized by hypoalbuminemia, pleural effusions, ascites, and peripheral edema. Other unexpected adverse events included elevated liver function tests and fatigue. The VLS and liver toxicity had delayed onset and increased in severity with subsequent cycles. Disease stabilization was achieved for >6 weeks in 10 patients; in 2 patients this was maintained for >12 weeks. There was no evidence of DNA interstrand cross-linking in human blood lymphocytes with the use of the comet assay. Evidence of DNA interaction in lymphocytes and tumor cells was shown through a sensitive gamma-H2AX assay. SJG-136 had linear pharmacokinetics across the dose range tested.. SJG-136 was associated with dose-limiting VLS and hepatotoxicity when administered by short injection every 21 days. DNA damage was noted, at all dose levels studied, in circulating lymphocytes. The etiology of the observed toxicities is unclear and is the subject of further preclinical research. Alternative clinical dosing strategies are being evaluated.

Topics: Adult; Aged; Antineoplastic Agents; Benzodiazepinones; DNA; Histones; Humans; Maximum Tolerated Dose; Middle Aged; Neoplasms; Pyrroles

Topics: Angiopoietin-2; Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Benzodiazepinones; Clinical Trials, Phase I as Topic; ErbB Receptors; Humans; Neoplasms; Ornithine; Pterins; Pyrroles; Receptor, EphA2; Societies, Scientific