Persistent prevention of oxaliplatin-induced peripheral neuropathy using calmangafodipir (PledOx®): a placebo-controlled randomised phase II study (PLIANT).

PURPOSE: Oxaliplatin causes disabling acute and chronic peripheral neuropathy. We explored the preventive effects of calmangafodipir, mimicking the mitochondrial enzyme manganese superoxide dismutase, thereby protecting cells from oxidative stress, in a placebo-controlled, double-blinded randomised phase II study (ClinicalTrials.gov.NCT01619423) in patients with metastatic colorectal cancer (mCRC). PATIENT AND METHODS: mCRC patients treated with modified FOLFOX-6 (folinic acid 200 mg/m2, 5-fluorouracil bolus 400 mg/m2, oxaliplatin 85 mg/m2 and 5-fluorouracil 2400 mg/m2 continuous infusion for 46 h) every fortnight for 8 cycles in first or second line were eligible. Calmangafodipir was given in a phase I dose-finding and in a phase II placebo-controlled study, as a 5-min infusion 10 min prior to oxaliplatin. Neurotoxicity was evaluated by the physician using the Oxaliplatin Sanofi Specific Scale and by the patient using the cold allodynia test and the Leonard scale. RESULTS: Eleven patients were included in phase I without any detectable toxicity to calmangafodipir. In the phase II study, 173 patients were randomised to placebo (n = 60), calmangafodipir 2 µmol/kg (n = 57) and calmangafodipir 5 µmol/kg (n = 45, initially 10 µmol/kg, n = 11). Calmangafodipir-treated patients (all three doses pooled) had less physician graded neurotoxicity (odds ratio (90% confidence interval one-sided upper level) 0.62(1.15), p = .16), significantly less problems with cold allodynia (mean 1.6 versus 2.3, p < .05) and significantly fewer sensory symptoms in the Leonard scale (cycle 1-8 mean 1.9 versus 3.0, p < .05 and during follow-up after 3 and 6 months, mean 3.5 versus 7.3, p < .01). Response rate, progression-free and overall survival did not differ among groups. CONCLUSIONS: Calmangafodipir at a dose of 5 µmol/kg appears to prevent the development of oxaliplatin-induced acute and delayed CIPN without apparent influence on tumour outcomes.

A phase I clinical trial of the histone deacetylase inhibitor belinostat in patients with advanced hematological neoplasia.

PURPOSE: To determine the safety, dose-limiting toxicity and maximum tolerated dose (MTD) of the novel hydroxamate histone deacetylase inhibitor belinostat (PXD101) in patients with advanced hematological neoplasms. PATIENTS AND METHODS: Sequential dose-escalating cohorts of three to six patients with hematological malignancies received belinostat administered as a 30-min i.v. infusion on days 1-5 of a 21-d cycle. Experience from a parallel dose-finding study in patients with solid tumors influenced the selection of the final dose. RESULTS: Sixteen patients received belinostat at one of three dose levels: 600 mg/m(2)/d (three patients), 900 mg/m(2)/d (three patients) and 1000 mg/m(2)/d (10 patients), the dose determined to be the MTD in a phase I solid tumor study [Steele et al. (2008) Clin Cancer Res, 14, 804-10]. The most common treatment-related adverse events (all grades) were nausea (50%), vomiting (31%), fatigue (31%) and flushing (31%). No grade 3 or 4 hematological toxicity compared with baseline occurred except one case of grade 3 lymphopenia. There were two related grade 4 adverse events of renal failure observed. Both events occurred in patients with multiple myeloma and had similar characteristics, i.e. an acute episode of decrease in renal function (pre-existing nephropathy in one patient), with a metabolic profile and decrease in tumor burden consistent with tumor lysis syndrome. No other related grade 4 events were noted. The only related grade 3 events noticed in more than one patient were fatigue and neurological symptoms (one patient had status epilepticus in association with uremia and one patient had paresthesia), all other related grade 3 events occurred in single patients. No cardiac events were noted. No complete or partial remissions were noted in these heavily pre-treated (median of four prior regimens) patients. However, five patients, including two patients with diffuse large-cell lymphoma [including one patient with transformed chronic myelocytic leukaemia (CLL)], two patients with CLL and one patient with multiple myeloma, achieved disease stabilization in of two to nine treatment cycles. CONCLUSIONS: Intravenous belinostat at 600, 900 and 1000 mg/m(2)/d is well tolerated by patients with hematological malignancies. The study was carried out in parallel to a similar dose-finding study in patients with solid tumors, in which the MTD was determined to be 1000 mg/m(2)/d days 1-5 in a 21-d cycle. This dose can also be recommended for phase II studies in patients with hematological neoplasms.

Identification of predictive biomarkers for the histone deacetylase inhibitor belinostat in a panel of human cancer cell lines.

Histone deacetylase inhibitors (HDACi) are promising epigenetic cancer chemotherapeutics rapidly approaching clinical use. HDACi increases acetylation levels of histone and non-histone proteins and causes an alteration in gene-expression levels, ultimately resulting in proliferation arrest or apoptosis of especially cancer cells. However, the precise mechanism of action of this class of therapeutics and the genes implicated in sensitivity remain obscure. Hence, there is a need for identifying predictive biomarkers. In this study, we examined the gene-expression levels of selected possible HDACi biomarkers, as suggested in the literature. This was correlated with the inherent sensitivity towards the HDACi belinostat in a panel of 18 wild-type cancer cell lines with up to a 30-fold difference in chemosensitivity, which matched IC50 data from the NCI60 screen. Of 16 genes examined, 4 showed a correlation in their expression levels to belinostat sensitivity: Ornithine decarboxylase (ODC1), v-ski sarcoma viral oncogene homolog (SKI), signal transducer and activator of transcription 1 (STAT1), and thymidylate synthetase (TYMS). Including ODC and SKI simultaneously further strengthened the model. Further, there was no correlation between sensitivity and intracellular belinostat uptake or with histone and tubulin acetylation. Therefore, the genes identified in this study may be potential biomarkers for predicting clinical HDACi sensitivity.

A phase 1 pharmacokinetic and pharmacodynamic study of the histone deacetylase inhibitor belinostat in patients with advanced solid tumors.

PURPOSE: To determine the safety, dose-limiting toxicity, maximum tolerated dose, and pharmacokinetic and pharmacodynamic profiles of the novel hydroxamate histone deacetylase inhibitor belinostat (previously named PXD101) in patients with advanced refractory solid tumors. EXPERIMENTAL DESIGN: Sequential dose-escalating cohorts of three to six patients received belinostat administered as a 30-min i.v. infusion on days 1 to 5 of a 21-day cycle. Pharmacokinetic variables were evaluated at all dose levels. Pharmacodynamic measurements included acetylation of histones extracted from peripheral blood mononuclear cells, caspase-dependent cleavage of cytokeratin-18, and interleukin-6 levels. RESULTS: Forty-six patients received belinostat at one of six dose levels (150-1,200 mg/m(2)/d). Dose-limiting toxicities were grade 3 fatigue (one patient at 600 mg/m(2); one patient at 1,200 mg/m(2)), grade 3 diarrhea combined with fatigue (one patient at 1,200 mg/m(2)), grade 3 atrial fibrillation (one patient at 1,200 mg/m(2); one patient at 1,000 mg/m(2)), and grade 2 nausea/vomiting leading to inability to complete a full 5-day cycle (two patients at 1,000 mg/m(2)). The maximum tolerated dose was 1,000 mg/m(2)/d. I.v. belinostat displayed linear pharmacokinetics with respect to C(max) and AUC. The intermediate elimination half-life was 0.3 to 1.3 h and was independent of dose. Histone H4 hyperacetylation was observed after each infusion and was sustained for 4 to 24 h in a dose-dependent manner. Increases in interleukin-6 levels were detected following belinostat treatment. Stable disease was observed in a total of 18 (39%) patients, including 15 treated for > or =4 cycles, and this was associated with caspase-dependent cleavage of cytokeratin-18. Of the 24 patients treated at the maximum tolerated dose (1,000 mg/m(2)/d), 50% achieved stable disease. CONCLUSIONS: I.v. belinostat is well tolerated, exhibits dose-dependent pharmacodynamic effects, and has promising antitumor activity.

Indication of a role of plasminogen activator inhibitor type I in protecting murine fibrosarcoma cells against apoptosis.

In a number of cancer types high tumor tissue levels of plasminogen activator inhibitor type 1 (PAI-1) protein are strongly associated with shorter cancer patient survival. This association has been intriguing since PAI-1 is known to inhibit urokinase plasminogen activator (uPA) that converts plasminogen to plasmin, which is actively involved in tumor progression and invasion. In order to further explore the biological role of PAI-1 in cancer, we have prepared fibroblasts from PAI-1 gene deficient mice and from their wild type littermates. From these fibroblasts fibrosarcoma cell lines were established and characterized. Both types of fibroblasts underwent spontaneous transformation as indicated by aneuploidy, immortalization, clonogenicity in soft agar and tumor formation in vivo. While both PAI-1 deficient and PAI-1 expressing cell lines showed similar proliferation rates in vitro, cells devoid of PAI-1 were significantly more sensitive to apoptotic stimuli. When inoculated subcutaneously into nude mice PAI-1 expressing cells rapidly established tumors, while PAI-1 deficient cells had a significantly longer lag-phase before they started to grow (p<0.0001). The present study suggests that PAI-1, besides its uPA inhibiting function, has a role in cancer progression by protecting tumor cells from undergoing apoptosis.