Phase II study of the histone deacetylase inhibitor MGCD0103 in patients with previously treated chronic lymphocytic leukaemia.

MGCD0103, an orally available class I histone deacetylase (HDAC) inhibitor, was examined for pre-clinical activity in chronic lymphocytic leukaemia (CLL). A phase II clinical trial was performed, starting at a dose of 85 mg/d, three times per week. Dose escalation to 110 mg or the addition of rituximab was permitted in patients without a response after two or more cycles.

Pharmacological inhibition of histone deacetylases for the treatment of cancer, neurodegenerative disorders and inflammatory diseases.

Background: Histone deacetylases (HDACs) constitute a family of enzymes that deacetylate histones and other cellular proteins. They are major regulators of transcription and are also important in other cellular processes.

Objective: The review provides an updated summary of HDAC pharmacological inhibition in clinical oncology, as well as in preclinical studies on inflammation and neurodegenerative diseases.

Evaluation of the pharmacodynamic effects of MGCD0103 from preclinical models to human using a novel HDAC enzyme assay.

Purpose: The pharmacodynamic properties of MGCD0103, an isotype-selective inhibitor of histone deacetylase (HDAC), were evaluated in preclinical models and patients with a novel whole-cell HDAC enzyme assay.

Experimental Design: Boc-Lys(epsilon-Ac)-AMC, a HDAC substrate with fluorescent readout, was found to be cell permeable and was used to monitor MGCD0103-mediated HDAC inhibition in cultured cancer cells in vitro, in peripheral WBC ex vivo, in mice in vivo, and in human patients.

Results: MGCD0103 inhibited HDAC activity in several human cancer cell lines in vitro and in human peripheral WBC ex vivo in a dose-dependent manner.

Phase 1 study of the oral isotype specific histone deacetylase inhibitor MGCD0103 in leukemia.

MGCD0103 is an isotype-selective inhibitor of histone deacetylases (HDACs) targeted to isoforms 1, 2, 3, and 11. In a phase 1 study in patients with leukemia or myelodysplastic syndromes (MDS), MGCD0103 was administered orally 3 times weekly without interruption. Twenty-nine patients with a median age of 62 years (range, 32-84 years) were enrolled at planned dose levels (20, 40, and 80 mg/m(2)).

MGCD0103, a novel isotype-selective histone deacetylase inhibitor, has broad spectrum antitumor activity in vitro and in vivo.

Nonselective inhibitors of human histone deacetylases (HDAC) are known to have antitumor activity in mice in vivo, and several of them are under clinical investigation. The first of these, Vorinostat (SAHA), has been approved for treatment of cutaneous T-cell lymphoma. Questions remain concerning which HDAC isotype(s) are the best to target for anticancer activity and whether increased efficacy and safety will result with an isotype-selective HDAC inhibitor.

Novel aminophenyl benzamide-type histone deacetylase inhibitors with enhanced potency and selectivity.

Significant effort is being made to understand the role of HDAC isotypes in human cancer and to develop antitumor agents with better therapeutic windows. A part of this endeavor was the exploration of the 14 A internal cavity adjacent to the enzyme catalytic site, which led to the design and synthesis of compound 4 with the unusual bis(aryl)-type pharmacophore. SAR studies around this lead resulted in optimization to potent, selective, nonhydroxamic acid HDAC inhibitors.

Sulfonamide anilides, a novel class of histone deacetylase inhibitors, are antiproliferative against human tumors.

Inhibition of histone deacetylases (HDACs) is emerging as a new strategy in human cancer therapy. We have designed and synthesized novel nonhydroxamate sulfonamide anilides that can inhibit human HDAC enzymes and can induce hyperacetylation of histones in human cancer cells. These compounds selectively inhibit proliferation and cause cell cycle blocks in various human cancer cells but not in normal cells.