OTX015 (MK-8628), a novel BET inhibitor, displays in vitro and in vivo antitumor effects alone and in combination with conventional therapies in glioblastoma models.

Bromodomain and extraterminal (BET) bromodomain (BRD) proteins are epigenetic readers that bind to acetylated lysine residues on chromatin, acting as co-activators or co-repressors of gene expression. BRD2 and BRD4, members of the BET family, are significantly increased in glioblastoma multiforme (GBM), the most common primary adult brain cancer. OTX015 (MK-8628), a novel BRD2/3/4 inhibitor, is under evaluation in dose-finding studies in solid tumors, including GBM. We investigated the pharmacologic characteristics of OTX015 as a single agent and combined with targeted therapy or conventional chemotherapies in glioblastoma cell lines. OTX015 displayed higher antiproliferative effects compared to its analog JQ1, with GI50 values of approximately 0.2 µM. In addition, C-MYC and CDKN1A mRNA levels increased transiently after 4 h-exposure to OTX015, while BRD2, SESN3, HEXIM-1, HIST2H2BE, and HIST1H2BK were rapidly upregulated and sustained after 24 h. Studies in three additional GBM cell lines supported the antiproliferative effects of OTX015. In U87MG cells, OTX015 showed synergistic to additive activity when administered concomitant to or before SN38, temozolomide or everolimus. Single agent oral OTX015 significantly increased survival in mice bearing orthotopic or heterotopic U87MG xenografts. OTX015 combined simultaneously with temozolomide improved mice survival over either single agent. The passage of OTX015 across the blood-brain barrier was demonstrated with OTX015 tumor levels 7 to 15-fold higher than in normal tissues, along with preferential binding of OTX015 to tumor tissue. The significant antitumor effects seen with OTX015 in GBM xenograft models highlight its therapeutic potential in GBM patients, alone or combined with conventional chemotherapies.

Influence of tumour burden on trastuzumab pharmacokinetics in HER2 positive non-metastatic breast cancer.

AIMS: Trastuzumab, an antibody binding to epidermal growth factor receptor-2 (HER2), has been approved to treat HER2-positive breast cancer in different settings. This study aimed at evaluating the influence of tumour size on trastuzumab pharmacokinetics (PK) in non-metastatic breast cancer patients treated with short term pre-operative trastuzumab. METHODS: Trastuzumab PK data were obtained from a multicentre, randomized and comparative study. This antibody was administered pre-operatively to patients with localized HER2-positive breast cancer as a single 4 mg kg(-1) loading dose followed by 5 weekly 2 mg kg(-1) doses. Trastuzumab concentrations were measured repeatedly using an ELISA technique. Tumour size was evaluated at baseline using breast echography. Trastuzumab pharmacokinetics were studied using a population approach and a two compartment model. The influence of tumour burden on trastuzumab pharmacokinetics was quantified as a covariate. RESULTS: A total of 784 trastuzumab concentrations were available from the 79 eligible patients. Estimated parameters (interindiviual standard deviation) were central volume of distribution =2.1 l (23%), peripheral volume of distribution =1.3 l (38%), intercompartment clearance =0.36 l day(-1) , with an elimination half-life of 11.8 days. Typical clearance was 0.22 l day(-1) (19%) and its value was increased with tumour size. In patients with the highest tumour size, trastuzumab clearance was 50% [18%-92%] higher than in patients with the lowest tumour size. CONCLUSIONS: In non-metastatic breast cancer patients, trastuzumab clearance increases with tumour size. The elimination half-life of trastuzumab was shorter in the present population of patients than in metastatic breast cancer patients previously studied.

A Phase I Trial of High-Dose Chemotherapy Combining Topotecan plus Cyclophosphamide with Hematopoietic Stem Cell Transplantation for Ovarian Cancer: The ITOV 01bis Study.

BACKGROUND: Dose-intensive chemotherapy with hematopoietic stem cell transplantation has been evaluated as a salvage treatment for recurrent ovarian cancer, but its benefit has not yet been demonstrated. In a previous phase I trial, we reported the feasibility of administering topotecan as a salvage regimen. METHODS: Twenty-one patients were treated with escalating doses of topotecan associated with a fixed dose of cyclophosphamide. RESULTS: The maximum tolerated dose was established at 9.0 mg/m2 on a 5-day regimen, analogously to what was reported for topotecan monotherapy. One toxic death from septic shock and multiorgan failure occurred. Although hematopoietic toxicities were overcome by peripheral blood stem cell transplantation, superior nonhematological toxicities were observed as compared to the initial trial. CONCLUSION: Response rates were generally short and survival rates were poor. Results of the ITOV 01bis study demonstrate that, in the setting of recurrent ovarian cancer, intensive chemotherapy based on topotecan-cyclophosphamide association is not currently clinically indicated.

Extracellular adenosine triphosphate affects the response of human macrophages infected with Mycobacterium tuberculosis.

Granulomas are the hallmark of Mycobacterium tuberculosis infection. As the host fails to control the bacteria, the center of the granuloma exhibits necrosis resulting from the dying of infected macrophages. The release of the intracellular pool of nucleotides into the surrounding medium may modulate the response of newly infected macrophages, although this has never been investigated. Here, we show that extracellular adenosine triphosphate (ATP) indirectly modulates the expression of 272 genes in human macrophages infected with M. tuberculosis and that it induces their alternative activation. ATP is rapidly hydrolyzed by the ecto-ATPase CD39 into adenosine monophosphate (AMP), and it is AMP that regulates the macrophage response through the adenosine A2A receptor. Our findings reveal a previously unrecognized role for the purinergic pathway in the host response to M. tuberculosis. Dampening inflammation through signaling via the adenosine A2A receptor may limit tissue damage but may also favor bacterial immune escape.

Influence of ABCB1 polymorphisms and docetaxel pharmacokinetics on pathological response to neoadjuvant chemotherapy in breast cancer patients.

We have previously reported an association between ABCB1 C3435T polymorphism and docetaxel pharmacokinetics in breast cancer patients. We therefore investigated whether these parameters could account for variations in pathological response. Five ABCB1 polymorphisms including C3435T polymorphism were analyzed in breast cancer patients receiving neoadjuvant chemotherapy with doxorubicin and docetaxel (n = 101). Pathological response was assessed using the Sataloff classification. Pharmacokinetic analysis was performed for the first course of docetaxel (n = 84). No significant association was found between ABCB1 polymorphisms or docetaxel pharmacokinetics and pathological complete response. C3435T genotype was an independent predictive factor of good response in breast (response >50 %, i.e., Sataloff T-A and T-B): OR: 4.6 (95 % CI: 1.3-16.1), p = 0.015, for TT patients versus CT and CC patients. Area under the plasma concentration-time curve (AUC) of docetaxel was the only independent predictive factor of the total absence of response in breast (Sataloff T-D): OR: 14.3, (95 % CI: 1.7-118), p = 0.015, for AUC of docetaxel <3,500 µg h/L versus ≥3,500 µg h/L. These results suggest that C3435T polymorphism and docetaxel exposure are involved in the response to neoadjuvant chemotherapy in breast cancer patients and may be useful to optimize individualized therapy.

Safety, pharmacokinetics, and activity of EZN-2208, a novel conjugate of polyethylene glycol and SN38, in patients with advanced malignancies.

BACKGROUND: EZN-2208 is a water-soluble, polyethylene glycol drug conjugate of SN38, which is the active moiety of irinotecan. In this study, the authors evaluated the tolerability, pharmacokinetics (PK), and activity of EZN-2208 in adult patients with advanced solid tumors. METHODS: Patients in sequential cohorts (3 + 3 design) received intravenous EZN-2208 at doses between 1.25 mg/m(2) and 25 mg/m(2) once every 21 days. RESULTS: Thirty-nine patients received EZN-2208. The median number of prior therapies was 2 (range, 0-10 prior therapies). Seventeen patients received prior irinotecan. Two maximum tolerated doses (MTDs) were defined: EZN-2208 with (16.5 mg/m(2)) and without (10 mg/m(2)) granulocyte-colony-stimulating factor (G-CSF). The dose-limiting toxicity (DLT) was febrile neutropenia. Two of 19 patients who were heterozygous for a polymorphism in the uridine diphosphate glucuronosyltransferase 1 family, polypeptide A1 (UGT1A1) gene (UGT1A1*28) developed DLTs (dose, 25 mg/m(2) with G-CSF), and 2 patients who were homozygous for UGT1A1*28 were treated without DLTs (dose, 5 mg/m(2)). PK analysis indicated a mean terminal half-life of 19.4 ± 3.4 hours. Sixteen patients (41%) achieved stable disease, including 6 of 39 patients (15%) who had stable disease that lasted ≥ 4 months. One patient with cholangiocarcinoma (no prior irinotecan) achieved a short-lived 32% tumor regression. Among 6 patients who had stable disease that lasted for ≥ 4 months, 3 had received prior irinotecan, and 1 had KRAS-positive colorectal cancer. CONCLUSIONS: EZN-2208 was well tolerated and produced stable disease that lasted for ≥ 4 months/unconfirmed partial responses in 7 of 39 heavily pretreated patients (18%) with advanced solid tumors, including those who had failed prior irinotecan therapy.

[Adaptation of methotrexate determination in serum with Unicel DxC600(®)]. / Adaptation du dosage sérique du méthotrexate sur Unicel DxC600(®).

High-dose methotrexate treatment requires pharmacological monitoring in order to tailor administration of folinic acid to reduce side effects. The aim of the study was to validate the adaptation of the EMIT reagent on the l'Unicel DxC 600® Beckman Coulter. The establishment of two assays was necessary to obtain a quantification limit as low as possible (0.05 µmol/L). The linearity of the adapted methods extends from 0.05 to 0.25 µmol/L on the one hand, and from 0.25 to 1 µmol/L on the other hand. For each method, fidelity and accuracy were studied and the limits of detection and quantification were quantified. The correlation with the FPIA method was performed on the Abbott TDX(®). The results of all tests are satisfactory with coefficients of variation (CV) of repeatability and reproducibility of less than 6%. However the daily assays are heavy as 66% of blood samples require at least two dosages and 30% a manual dilution.

Effects of protein kinase C modulation by PEP005, a novel ingenol angelate, on mitogen-activated protein kinase and phosphatidylinositol 3-kinase signaling in cancer cells.

PEP005 (ingenol-3-angelate) is a novel anticancer agent extracted from Euphorbia peplus that was previously shown to modulate protein kinase C (PKC), resulting in antiproliferative and proapoptotic effects in several human cancer cell lines. In Colo205 colon cancer cells, exposure to PEP005 induced a time- and concentration-dependent decrease of cells in S phase of cell cycle and apoptosis. In Colo205 cells exposed to PEP005, a variety of signaling pathways were activated as shown by increased phosphorylation of PKCdelta, Raf1, extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase (MAPK), c-Jun NH(2)-terminal kinase, p38 MAPK, and PTEN. PEP005-induced activation of PKCdelta was associated with its translocation from the cytosol to the nucleus and other cellular membranes. Interestingly, PEP005 treatment also resulted in reduced expression of PKCalpha and reduced levels of phosphorylated active form of AKT/protein kinase B. These data suggest that PEP005-induced activation of PKCdelta and reduced expression of PKCalpha resulted in apoptosis by mechanisms mediated by activation of Ras/Raf/MAPK and inhibition of the phosphatidylinositol 3-kinase/AKT signaling pathways. This study supports ongoing efforts targeting PKC isoforms in cancer therapy with PEP005 alone and in combination with other cytotoxic agents.

Antiproliferative effects of rapamycin as a single agent and in combination with carboplatin and paclitaxel in head and neck cancer cell lines.

PURPOSE: Recent data suggested that combining targeted therapies with chemotherapy may counteract drug resistance. Activation of the PI3K/AKT/mTOR pathway downstream to kinase receptors, such as EGFR, was found in 57-81% of head and neck squamous cell carcinoma (HNSCC), and was eventually associated with a loss of PTEN function. mTOR was shown to modulate cell proliferation, apoptosis, invasion, and angiogenesis. This study aimed to evaluate molecular and cellular effects of rapamycin in a panel of cell lines either as single agent or in combination with cytotoxics commonly used in HNSCC. METHODS: Antiproliferative effects of rapamycin, carboplatin, and paclitaxel were evaluated in a panel of three HNSCC cell lines (SCC61, SQ20B and HEP2). Cells were exposed to rapamycin for 48 h, to carboplatin for 48 h, or to paclitaxel for 24 h. Antiproliferative effects of simultaneous and sequential rapamycin-based combinations were studied using MTT assay and median effect plot analysis. Cell cycle effects were analysed using flow cytometry. RESULTS: Rapamycin induced concentration dependent antiproliferative effects in HNSCC cell lines with IC(50) of 5 +/- 1, 12 +/- 2 and 20 +/- 2 microM in SCC61, SQ20B, and HEP2 cells, respectively. Higher antiproliferative effects were observed in SCC61 cells overexpressing NOXA and cyclin D1 than in HEP2 that overexpressed MDR1 and BCL2. In our panel, antiproliferative effects of rapamycin were associated with G0/G1 cell cycle accumulation and apoptosis induction, at concentrations ranging 3-30 microM. Combinations of rapamycin with paclitaxel and carboplatin displayed synergistic and additive effects. Synergistic effects were observed with paclitaxel in SQ20B and HEP2 cells and with carboplatin in SQ20B cells, when cells were exposed to cytotoxics prior to rapamycin. CONCLUSION: Our results show that rapamycin displays antiproliferative effects and induces apoptosis in HNSCC cell lines, cellular effects being more potent in cells that do not express BCL2 and MDR1. Additive and synergistic effects were observed when rapamycin was combined with carboplatin and paclitaxel.

Population pharmacokinetics and exploratory pharmacodynamics of ifosfamide according to continuous or short infusion schedules: an n = 1 randomized study.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: * The optimal infusion duration for ifosfamide remains to be determined. * No differences according to time of infusion have been identified in traditional pharmacokinetic endpoints, such as area under the curve. * The impact on pharmacodynamics has never been modelled or correlated with pharmacokinetics. WHAT THIS STUDY ADDS: * The pharmacokinetics and pharmacodynamics of ifosfamide and its main metabolites can both be modelled with no influence of infusion duration. * Pharmacodynamic modelling (renal and haematological toxicity) allows further simulations of new schedules with favourable toxicity profiles. AIMS: To model the pharmacokinetics and pharmacodynamics of ifosfamide and its key metabolites. The pharmacodynamic parameters included were renal toxicity and myelosuppression measured using urinary beta(2)-microglobulin (BMG) and absolute neutrophil count (ANC), respectively. METHODS: Seventeen patients were enrolled into an n = 1 randomized trial during two consecutive cycles of ifosfamide 9 g m(-2) during each cycle given by a 3 h or 72 h infusion. Data were analyzed using NONMEM. RESULTS: Ifosfamide and metabolite concentration-time profiles were described by a one-compartment open-model with auto-induction of clearance. BMG and ANC time-courses were related to ifosfamide concentration via indirect response models. CONCLUSIONS: This modelling allowed the simulation of weekly schedules of flat doses with favourable myelotoxic profiles.

Phase I study of onapristone, a type I antiprogestin, in female patients with previously treated recurrent or metastatic progesterone receptor-expressing cancers.

INTRODUCTION: Onapristone is a type I progesterone receptor (PR) antagonist, which prevents PR- mediated DNA transcription. Onapristone is active in multiple preclinical models and two prior studies demonstrated promising activity in patients with breast cancer. We conducted a study of extended release (ER) Onapristone to determine a recommended dose and explore the role of transcriptionally-activated PR (APR), detected as an aggregated subnuclear distribution pattern, as a predictive biomarker. METHODS: An open-label, multicenter, randomized, parallel-group, phase 1 study (target n = 60; NCT02052128) included female patients ≥18 years with PRpos tumors. APR analysis was performed on archival tumor tissue. Patients were randomized to five cohorts of extended release (ER) onapristone tablets 10, 20, 30, 40 or 50 mg BID, or immediate release 100 mg QD until progressive disease or intolerability. Primary endpoint was to identify the recommended phase 2 dose. Secondary endpoints included safety, clinical benefit and pharmacokinetics. RESULTS: The phase 1 dose escalation component of the study is complete (n = 52). Tumor diagnosis included: endometrial carcinoma 12; breast cancer 20; ovarian cancer 13; other 7. Median age was 64 (36-84). No dose limiting toxicity was observed with reported liver function test elevation related only to liver metastases. The RP2D was 50 mg ER BID. Median therapy duration was 8 weeks (range 2-44), and 9 patients had clinical benefit ≥24 weeks, including 2 patients with APRpos endometrial carcinoma. CONCLUSION: Clinical benefit with excellent tolerance was seen in heavily pretreated patients with endometrial, ovarian and breast cancer. The data support the development of Onapristone in endometrial endometrioid cancer. Onapristone should also be evaluated in ovarian and breast cancers along with APR immunohistochemistry validation.

Impact of imatinib on the pharmacokinetics and in vivo efficacy of etoposide and/or ifosfamide.

BACKGROUND: Using a human small cell lung cancer (SCLC) xenografted in nude mice, we have previously reported enhanced tumor growth inhibition following chemotherapy in combination with imatinib (STI571). We therefore investigated the in vivo impact of imatinib on the pharmacokinetics and efficacy of chemotherapy. METHODS: Two different human tumors were used: SCLC6 small cell lung cancer xenografted in nude mice, and LY-3 EBV-associated human B-cell lymphoma xenografted in SCID mice. Plasma, urine, and fecal concentrations of etoposide (VP16) were determined by a validated high performance liquid chromatography method. Plasma concentrations of ifosfamidewere determined by a validated gas chromatography assay with nitrogen-phosphorus detection. RESULTS: Slight tumor growth inhibition was induced by imatinib administered alone in one in vivo EBV-associated B-cell lymphomatous xenograft. In contrast, an increase of the chemotherapy-induced antitumor effect was observed in the lymphoma model but not in a small cell lung cancer model when mice bearing human xenografted tumors were treated concomitantly by imatinib and chemotherapy. This antitumor effect was not influenced by concomitant administration of fluconazole. The AUC0-3 h (Area Under the concentration-time Curve) of etoposide was increased when mice were treated with etoposide + imatinib due to decreased fecal excretion. In contrast, imatinib did not appear to influence the urinary excretion of etoposide, and concomitant administration of the CYP3A4 inhibitor, fluconazole, with imatinib did not modify the pharmacokinetics of etoposide plus imatinib alone. CONCLUSION: Altogether, these results therefore justify further prospective phase I and II clinical trials with combinations of etoposide-based chemotherapy and imatinib in patients with certain cancers, such as malignant lymphoma, with careful toxicologic monitoring.

Validation of an ergonomic method to withdraw [99mTc] radiopharmaceuticals.

The main objective of the present work was to ensure quality of radiopharmaceuticals syringes withdrawn with a "Spinal needle/obturator In-Stopper" system. Methods: Visual examinations and physicochemical tests are performed at T0 and T+4h for [99mTc]albumin nanocolloid and T+7h for [99mTc]eluate, [99mTc] HydroxyMethylene DiPhosphonate and [99mTc]Human Serum Albumin. Microbiological validation was performed according to European pharmacopoeia. Fingertip radiation exposure was evaluated to confirm the safety of the system. Results: Results show stable visual and physicochemical properties. The integrity of the connector was not affected after 30 punctures (no cores). No microbiological contamination was found on tested syringes. Conclusion: The system could be used 30 times. The stability of syringes drawing with this method is guaranteed up to 4 hours for [99mTc]albumin nanocolloid and 7 hours for [99mTc]eluate, [99mTc]HydroxyMethylene DisPhosphonate and [99mTc]Human serum albumin.

PIKHER2: A phase IB study evaluating buparlisib in combination with lapatinib in trastuzumab-resistant HER2-positive advanced breast cancer.

BACKGROUND: Phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin pathway is frequently activated in HER2-positive breast cancer and may play a major role in resistance to trastuzumab. Buparlisib is a pan-class-I PI3K inhibitor with potent and selective activity against wild-type and mutant PI3K p110 isoforms. PATIENTS AND METHODS: PIKHER2 phase IB study aimed primarily to determine a maximum tolerated dose (MTD) and propose a recommended phase II dose (RP2D) for buparlisib in combination with lapatinib in HER2-positive, trastuzumab-resistant, advanced breast cancer. Oral buparlisib (40, 60 or 80 mg) and lapatinib (750, 1000 or 1250 mg) were administered daily. A modified continuous reassessment method using an adaptive Bayesian model guided the dose escalation of both agents. Secondary end-points included antitumour activity and pharmacokinetic (PK) assessments. RESULTS: A total of 24 patients were treated across five dose levels. Dose-limiting toxicities included transaminases elevation, vomiting, stomatitis, hyperglycemia and diarrhoea. MTD was declared at buparlisib 80 mg/d + lapatinib 1250 mg/d, but toxicities and early treatment discontinuation rate beyond cycle 1 led to select buparlisib 80 mg + lapatinib 1000 mg/d as the RP2D. Main drug-related adverse events included diarrhoea, nausea, skin rash, asthenia, depression, anxiety and transaminases increase. There was no significant evidence for drug-drug PK interaction. Disease control rate was 79% [95% confidence interval [CI] 57-92%], one patient obtained a complete remission, and six additional patients experienced stable disease for ≥ 24 weeks (clinical benefit rate of 29% [95% CI 12-51%]). CONCLUSION: Combining buparlisib and lapatinib in HER2-positive trastuzumab-resistant advanced breast cancer was feasible. Preliminary evidence of antitumour activity was observed in this heavily pre-treated population. TRIAL REGISTRATION ID: NCT01589861.

Preclinical and clinical development of novel agents that target the protein kinase C family.

Protein kinase C (PKC) family comprises more than 12 serine-/threonine-specific isoenzymes. PKC isoenzymes play a complex role in the transduction of signal from tyrosine kinase receptor modulating proliferation, cell cycle, apoptosis, invasion, differentiation, and senescence in both cancer cells and endothelial cells. Thereby, inhibition and/or activation of specific PKCs is thought to control tumor growth by interacting directly with cancer cells and indirectly by blocking tumor angiogenesis. Furthermore, PKCs are known to modulate multi-drug resistance, providing a rational for the combination of PKCs modulators with classical cytotoxic drugs. During the past few years, preclinical and clinical data with first-generation PKC inhibitors/activators provided insight that PKCs may indeed represent attractive targets for the discovery of small molecules with new anticancer properties. In this review, we will provide an overview on the current understanding of PKC participation in chemotherapeutic resistance, the possible implications in cancer treatment, and the potential of most recent PKC inhibitors in molecular cancer therapeutics.

Characterizations of irofulven cytotoxicity in combination with cisplatin and oxaliplatin in human colon, breast, and ovarian cancer cells.

PURPOSE: This study assessed the cytotoxic effects of irofulven in combination with oxaliplatin and cisplatin in a panel of human cancer cell lines. METHODS: Growth inhibition studies were performed using the human HT29 colon cancer cell line, irofulven-resistant derivative HT29/IF2, breast cancer cell line MCF7, and ovarian cancer line CAOV3. Irofulven-oxaliplatin combinations were compared with irofulven-cisplatin combinations in the same cell lines using similar experimental settings. Cells were exposed for 1 h to irofulven and then for 24 h to oxaliplatin or cisplatin and vice versa. RESULTS: Single agent irofulven displayed cytotoxic effects against human colon HT29 cells, human breast cancer cell lines including MCF7, SKBR3, and ZR-75-1, and human ovarian cancer cell lines CAOV3, OVCAR3, and IGROV1, with OVCAR3 being the most sensitive cancer cell line (IC50: 2.4 microM). In all tested cell lines the oxaliplatin-irofulven combination led to clear evidence of synergistic activity. In HT29 and HT29/IF2, the sequence oxaliplatin followed by irofulven appears to be the most effective whereas in MCF7 cells, irofulven given prior to or simultaneously with oxaliplatin is more effective than the other schedule. The combination displays additive activity toward CAOV3 ovarian cells when irofulven was administered prior to or simultaneously with oxaliplatin and partially synergistic when oxaliplatin was followed by irofulven. In most of the cell lines, the sequence oxaliplatin followed by irofulven appears to be the most effective as compared to other schedules. A combination of irofulven with cisplatin has the same efficacy as with oxaliplatin for the same cell lines. Cell cycle studies show that irofulven increases the proportion of cells in the S phase. Cisplatin-irofulven and oxaliplatin-irofulven combinations block cells in G1/S and potently induce apoptosis. CONCLUSION: Irofulven displays synergistic antiproliferative and pro-apoptotic effects when combined with oxaliplatin over a broad range of concentrations in human colon and breast cancer cells. Acquired resistance to irofulven has limited impact on the effects of cisplatin-irofulven and oxaliplatin-irofulven combinations. Based on these data, irofulven-oxaliplatin and cisplatin-irofulven combinations will be further explored in clinical trials, favoring the use schedules of oxaliplatin given prior to irofulven in patients with cancer.

Variations of soluble fas and cytokeratin 18-Asp 396 neo-epitope in different cancers during chemotherapy.

Soluble Fas (sFas) and cytokeratin 18-Asp396 neoepitope (CK18-NE) were measured by ELISA in serial samples from 42 patients with different cancers under chemotherapy and were compared with pharmacokinetic results. Baseline sFas (median 6146 pg/ml, range 3123-16294 pg/ml) was higher in cancer patients than in normal subjects (median 4954 pglml, range 2595-10565 pg/ml, n =95) (p <0.01) and increased with the number of previous chemotherapy lines (p =0.008). During pharmacokinetics, the median sFas response differed significantly with tumour histology (p<0.001) and was correlated to 5-Fluorouracil (rho=0.366, p=0.015, n=45) or cisplatin (rho=0.509, p=0.025, n=21) concentrations but not to anthracyclines or oxazaphosphorine. By Kaplan-Meier analysis, patients with baseline sFas <6146 pg/ml had a longer survival probability (p=0.002). The median baseline CK18-NE did not differ from normal subjects, but its maximum increase differed according to histology (p=0.007) and to drug type (p=0.028). Patients with a maximum increase >67.5% (median) during chemotherapy had a better univariate overall survival (p=0.021). As measured by sFas concentration, chemotherapy induces an anti-apoptotic response of differing intensity according to tumour types and drugs, which has a prognostic value for survival. A CK18-NE elevation, indicative of chemotherapy-induced apoptosis, is linked to good prognosis.

Bromodomain inhibitor OTX015 in patients with acute leukaemia: a dose-escalation, phase 1 study.

BACKGROUND: Bromodomain and extraterminal (BET) proteins are chromatin readers that preferentially affect the transcription of genes with super-enhancers, including oncogenes. BET proteins bind acetylated histone tails via their bromodomain, bringing the elongation complex to the promoter region. OTX015 (MK-8628) specifically binds to BRD2, BRD3, and BRD4, preventing BET proteins from binding to the chromatin, thus inhibiting gene transcription. OTX015 inhibits proliferation in many haematological malignancy cell lines and patient cells, in vitro and in vivo. We aimed to establish the recommended dose of OTX015 in patients with haematological malignancies. We report the results of patients with acute leukaemia (leukaemia cohort). METHODS: In this dose-escalation, phase 1 study we recruited patients from seven university hospital centres (in France [five], UK [one], and Canada [one]). Adults with acute leukaemia who had failed or had a contraindication to standard therapies were eligible to participate. OTX015 was given orally at increasing doses from 10 mg/day to 160 mg/day (14 of 21 days), using a conventional 3 + 3 design. In this open-label trial, OTX015 was initially administered once a day, with allowance for exploration of other schedules. The primary endpoint was dose-limiting toxicity (DLT), assessed during the first treatment cycle (21 days). The study is ongoing and is registered with ClinicalTrials.gov, NCT01713582. FINDINGS: Between Jan 18, 2013, and Sept 9, 2014, 41 patients, 36 with acute myeloid leukaemia, a median age of 70 years (IQR 60-75) and two lines of previous therapy, were recruited and treated across six dose levels of OTX015. No DLT was recorded until 160 mg/day, when one patient had grade 3 diarrhoea and another had grade 3 fatigue. However, concomitant grade 1-2 non-DLT toxic effects (ie, gastrointestinal, fatigue, or cutaneous) from 120 mg doses hampered patient compliance and 80 mg once a day was judged the recommended dose with a 14 days on, 7 days off schedule. Common toxic effects for all OTX015 doses were fatigue (including grade 3 in three patients) and bilirubin concentration increases (including grade 3-4 in two patients). OTX015 plasma exposure increased proportionally up to 120 mg/day with trough concentrations in the in-vitro active range from 80 mg/day (274 nmol/L). Three patients (receiving 40 mg/day, 80 mg/day, and 160 mg/day) achieved complete remission or complete remission with incomplete recovery of platelets lasting 2-5 months, and two additional patients had partial blast clearance. No predictive biomarkers for response have been identified so far. INTERPRETATION: The once-daily recommended dose for oral, single agent oral OTX015 use in patients with acute leukaemia for further phase 2 studies is 80 mg on a 14 days on, 7 days off schedule. FUNDING: Oncoethix GmbH, a wholly owned subsidiary of Merck Sharp & Dohme Corp.

Phase I Population Pharmacokinetic Assessment of the Oral Bromodomain Inhibitor OTX015 in Patients with Haematologic Malignancies.

BACKGROUND AND OBJECTIVES: OTX015 (MK-8628) is a novel inhibitor of the bromodomain and extraterminal (BET)-bromodomain (BRD) protein family, binding specifically to bromodomains BRD2/3/4 and impacting the epigenetic regulation of several oncogenes. We characterized the pharmacokinetics of this first-in-class BET-BRD inhibitor administered as a single agent, including population pharmacokinetic modelling. METHODS: A dose-escalation, phase Ib study was performed with oral OTX015 in patients with haematologic malignancies, at doses starting from 10 mg once daily (QD) with continuous or discontinuous schedules. Five or eight blood samples were collected per patient for pharmacokinetic analysis. OTX015 plasma concentrations were determined using validated ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and analysed using a nonlinear mixed-effects modelling software program. A population pharmacokinetic model was fitted to the data, and patient demographics and clinical chemistry parameters were tested as predictive covariates on the model parameters. RESULTS: Blood samples were analysed from 81 patients treated with OTX015 at doses ranging from 10 to 160 mg QD or 40 mg twice daily (BID), and 633 time-plasma concentrations were available for analysis. A one-compartment open model with linear elimination adequately described OTX015 pharmacokinetics. The most significant covariate was lean body mass (LBM), which decreased the between-subject variability in apparent total body clearance (CL) and the volume of distribution (V). The estimated pharmacokinetic parameters were the absorption rate constant (k a) = 0.731 h(-1), V = 71.4 L and CL = 8.47 L·h(-1). CONCLUSION: The pharmacokinetics of oral OTX015 in patients with haematologic malignancies can be described with a one-compartment model. Population pharmacokinetic modelling of OTX015 plasma concentrations showed that LBM influences V and CL. These findings do not suggest the need for dose adjustment.

Bromodomain inhibitor OTX015 in patients with lymphoma or multiple myeloma: a dose-escalation, open-label, pharmacokinetic, phase 1 study.

BACKGROUND: The first-in-class small molecule inhibitor OTX015 (MK-8628) specifically binds to bromodomain motifs BRD2, BRD3, and BRD4 of bromodomain and extraterminal (BET) proteins, inhibiting them from binding to acetylated histones, which occurs preferentially at super-enhancer regions that control oncogene expression. OTX015 is active in haematological preclinical entities including leukaemia, lymphoma, and myeloma. We aimed to establish the recommended dose of OTX015 in patients with haematological malignancies. We report the results from a cohort of patients with lymphoma or multiple myeloma (non-leukaemia cohort). METHODS: In this dose-escalation, open-label, phase 1 study, we recruited patients from seven university hospital centres (in France [four], Switzerland [one], UK [one], and Italy [one]). Adult patients with non-leukaemia haematological malignancies who had disease progression on standard therapies were eligible to participate. Patients were treated with oral OTX015 once a day continuously over five doses (10 mg, 20 mg, 40 mg, 80 mg, and 120 mg), using a conventional 3 + 3 design, with allowance for evaluation of alternative administration schedules. The primary endpoint was dose-limiting toxicity (DLT) in the first treatment cycle (21 days). Secondary objectives were to evaluate safety, pharmacokinetics, and preliminary clinical activity of OTX015. The study is ongoing and is registered with ClinicalTrials.gov, number NCT01713582. FINDINGS: Between Feb 4, 2013, and Sept 5, 2014, 45 patients (33 with lymphoma and 12 with myeloma), with a median age of 66 years (IQR 55-72) and a median of four lines of prior therapy (IQR 3-5), were enrolled and treated. No DLTs were observed in the doses up to and including 80 mg once a day (first three patients). We then explored a schedule of 40 mg twice a day (21 of 21 days). DLTs were reported in five of six patients receiving OTX015 at this dose and schedule (all five patients had grade 4 thrombocytopenia). We explored various schedules at 120 mg once a day but none was tolerable, with DLTs of thrombocytopenia, gastrointestinal events (diarrhoea, vomiting, dysgeusia, mucositis), fatigue, and hyponatraemia in 11 of 18 evaluable patients. At this point, the Safety Monitoring Committee decided to establish the feasibility of 80 mg once a day on a continuous basis, and four additional patients were enrolled at this dose. DLTs (grade 4 thrombocytopenia) was noted in two of the patients. In light of these DLTs and other toxicities noted at 120 mg, the dose of 80 mg once a day was selected, although on a schedule of 14 days on, 7 days off. Common toxic effects reported in the study were thrombocytopenia (43 [96%] patients), anaemia (41 [91%]), neutropenia (23 [51%]), diarrhoea (21 [47%]), fatigue (12 [27%]), and nausea (11 [24%]). Grade 3-4 adverse events were infrequent other than thrombocytopenia (26 [58%]). OTX015 plasma peak concentrations and areas under the concentration versus time curve increased proportionally with dose. Trough concentrations increased less than proportionally at lower doses, but reached or exceeded the in-vitro active range at 40 mg twice a day and 120 mg once a day. Three patients with diffuse large B-cell lymphoma achieved durable objective responses (two complete responses at 120 mg once a day, and one partial response at 80 mg once a day), and six additional patients (two with diffuse large B-cell lymphoma, four with indolent lymphomas) had evidence of clinical activity, albeit not meeting objective response criteria. INTERPRETATION: The once-daily recommended dose for oral, single agent oral OTX015 in patients with lymphoma is 80 mg on a 14 days on, 7 days off schedule, for phase 2 studies. OTX015 is under evaluation in expansion cohorts using this intermittent administration (14 days every 3 weeks) to allow for recovery from toxic effects. FUNDING: Oncoethix GmbH (a wholly owned subsidiary of Merck Sharp & Dohme Corp).