Integrative population pharmacokinetic and pharmacodynamic dose finding approach of the new camptothecin compound namitecan (ST1968).

AIMS: Namitecan is a new camptothecan compound undergoing early clinical development. This study was initiated to build an integrated pharmacokinetic (PK) and pharmacodynamic (PD) population model of namitecan to guide future clinical development. METHODS: Plasma concentration-time data, neutrophils and thrombocytes were pooled from two phase 1 studies in 90 patients with advanced solid tumours, receiving namitecan as a 2 h infusion on days 1 and 8 every 3 weeks (D1,8) (n = 34), once every 3 weeks (D1) (n = 29) and on 3 consecutive days (D1-3) (n = 27). A linear three compartment PK model was coupled to a semiphysiological PD-model for neutrophils and thrombocytes. Data simulations were used to interrogate various dosing regimens and give dosing recommendations. RESULTS: Clearance was estimated to be 0.15 l h(-1), with a long terminal half-life of 48 h. Body surface area was not associated with clearance, supporting flat-dosing of namitecan. A significant and clinically relevant association was found between namitecan area under the concentration-time curve (AUC) and the percentage drop of neutrophils (r(2) = 0.51, P < 10(-4)) or thrombocytes (r(2) = 0.49, P < 10(-4)). With a target for haematological dose-limiting toxicity of <20%, the recommended dose was defined as 12.5 mg for the D1,8 regimen, 23 mg for the once every 3 week regimen and 7 mg for the D1-3 regimen. CONCLUSION: This is the first integrated population PK-PD analysis of the new hydrophilic topoisomerase I inhibitor namitecan, that is currently undergoing early clinical development. A distinct relationship was found between drug exposure and haematological toxicity, supporting flat-dosing once every 3 weeks as the most adequate dosing regimen.

Phase Ib study of weekly mammalian target of rapamycin inhibitor ridaforolimus (AP23573; MK-8669) with weekly paclitaxel.

BACKGROUND: The additive cytotoxicity in vitro prompted a clinical study evaluating the non-prodrug rapamycin analogue ridaforolimus (AP23573; MK-8669; formerly deforolimus) administered i.v. combined with paclitaxel (PTX; Taxol). MATERIALS AND METHODS: Patients with taxane-sensitive solid tumors were eligible. The main dose escalation foresaw 50% ridaforolimus increments from 25 mg with a fixed PTX dose of 80 mg/m(2), both given weekly 3 weeks in a 4-week cycle. Collateral levels with a lower dose of either drug were planned upon achievement of the maximum tolerated dose in the main escalation. Pharmacodynamic studies in plasma, peripheral blood mononuclear cells (PBMCs) and skin biopsies and pharmacokinetic (PK) interaction studies at cycles 1 and 2 were carried out. RESULTS: Two recommended doses were determined: 37.5 mg ridaforolimus/60 mg/m(2) PTX and 12.5 mg/80 mg/m(2). Most frequent toxic effects were mouth sores (79%), anemia (79%), fatigue (59%), neutropenia (55%) and dermatitis (48%). Two partial responses were observed in pharyngeal squamous cell and pancreatic carcinoma. Eight patients achieved stable disease > or =4 months. No drug interaction emerged from PK studies. Decrease of eukaryotic initiation factor 4E-binding protein1 (4E-BP1) phosphorylation was shown in PBMCs. Similar inhibition of phosphorylation of 4E-BP1 and mitogen-activated protein kinase was present in reparative epidermis and vascular tissues, respectively. CONCLUSION: Potential antiangiogenic effects and encouraging antitumor activity justify further development of the combination.

Clinical and pharmacological phase I evaluation of Exherin (ADH-1), a selective anti-N-cadherin peptide in patients with N-cadherin-expressing solid tumours.

BACKGROUND: Upregulation of N-cadherin promotes dysregulated cell growth, motility, invasiveness, plus maintenance of vascular stability and is associated with cancer progression in several human tumour types. N-cadherin is expressed also on tumour cells and the anti-N-cadherin cyclic pentapeptide ADH-1, tested in the present study, can exert a direct antitumour effect. PATIENTS AND METHODS: Adult patients with advanced solid malignancies expressing N-cadherin on tumour biopsies carried out in the previous 12 months received escalating i.v. doses of ADH-1 given weekly (initially for 3 of 4 weeks, then every week). Plasma pharmacokinetics (PK) was studied at cycle 1. Blood flow changes were assessed after first dosing in all patients treated in the initial regimen. RESULTS: In all, 129 patients were screened, 65 (50%) were N-cadherin positive, and 30 were enrolled. The doses ranged from 150 to 2400 mg/m(2); no maximum tolerated dose was reached. Treatment was well tolerated with asthenia as the most frequent adverse event. Two patients with ovarian cancer showed prolonged disease stabilisation while one patient with fallopian tube carcinoma achieved a mixed response. PK was linear in the range of doses tested. CONCLUSION: ADH-1 is the first anti-N-cadherin compound tested in humans. In N-cadherin-positive patients, ADH-1 showed an acceptable toxicity profile, linear PK and hints of antitumour activity in gynaecological cancers.

A phase I study of PankoMab-GEX, a humanised glyco-optimised monoclonal antibody to a novel tumour-specific MUC1 glycopeptide epitope in patients with advanced carcinomas.

BACKGROUND: A phase I open-label dose-escalation study was conducted to define the safety, tolerability, and pharmacokinetics (PK) of PankoMab-GEX, a glyco-optimised humanised IgG1, with high affinity to a novel tumour-specific glycopeptide epitope of MUC1 (TA-MUC1) with excellent preclinical anti-tumour activity. PATIENTS AND METHODS: Seventy-four patients with advanced TA-MUC1-positive carcinomas received PankoMab-GEX intravenously every 3 (Q3W), 2 (Q2W), or 1 (QW) week in doses of 1-2200 mg in a three-plus-three dose-escalation design until disease progression (NCT01222624). RESULTS: No maximum tolerated dose was reached. Adverse events were mainly mild-to-moderate infusion-related reactions (IRRs) by the first infusion in 45% of patients. Only one dose-limiting toxicity, a grade III IRR, was observed. PankoMab-GEX exhibited linear PK over all doses. Mean terminal half-life was 189 ± 66 h (Q3W), without dose dependency. A target trough level ≥50 µg/mL was reached after one infusion with doses ≥1700 mg Q3W in 80% of patients. Clinical benefit in 60 evaluable patients included one complete response in a patient with ovarian cancer treated 483 d and confirmed disease stabilisation in 19 patients lasting a median (range) of 23 (10-109) weeks. All but two of the patients with clinical benefit had received a compounded total dose ≥700 mg over a 3-week period, including 8 of 12 (67%) patients with ovarian cancer. CONCLUSION: PankoMab-GEX is safe, well tolerated, and showed promising anti-tumour activity in advanced disease. A phase IIb study is ongoing evaluating the efficacy of PankoMab-GEX as a maintenance therapy in advanced ovarian cancer.

Clinical and pharmacologic study of the epirubicin and paclitaxel combination in women with metastatic breast cancer.

PURPOSE: A pharmacokinetic interaction may cause increased cardiotoxicity of paclitaxel (PTX) and high cumulative dose of doxorubicin. We tested antitumor activity, tolerability, and pharmacokinetics of the lesser cardiotoxic epirubicin (EPI) and PTX (ET combination). PATIENTS AND METHODS: Twenty-seven women with untreated metastatic breast cancer, median age of 56 years, and prominent visceral involvement (74%) were studied. Three-weekly EPI (90 mg/m(2)) and PTX (200 mg/m(2) over 3 hours) were given for a maximum nine cycles. EPI was administered 24 hours before PTX (E --> T) in cycle 1, and 15 minutes before PTX (ET) thereafter. EPI, epirubicinol (EOL), EPI-glucuronide (EPI-glu), EOL-glucuronide (EOL-glu), PTX, and 6alpha-OH-PTX were measured in plasma and urine in 14 women. RESULTS: Patients received 205 cycles of ET and a median EPI dose of 720 mg/m(2). Grade 4 neutropenia (49% of cycles) was the most frequent toxicity. Cardiac contractility was decreased in five patients. Mild congestive heart failure occurred in two (7.4%). Response rate was 76% (28% complete). Median overall survival was 29 months. On the basis of intrapatient comparison in the first 24 hours of E --> T and ET cycles, PTX did not affect EPI disposition, but significantly increased plasma exposure to EOL (by 137%), EPI-glu (threefold) and EOL-glu (twofold). Urinary excretion of EPI dose went from 8.2% in E --> T to 11.8% in ET cycles. Clearance of PTX was 30% slower in ET than E --> T. ET cycles caused lower neutrophil nadir than E --> T (644 +/- 327 v 195 +/- 91, P <.05) CONCLUSION: ET is feasible, devoid of excessive cardiac toxicity, and active. A reciprocal pharmacokinetic interference between the two drugs has pharmacodynamic consequences, and suggests a direct effect of PTX on EPI metabolism requiring ad hoc investigation.

Chromogranin A measurement in neuroendocrine tumors.

Neuroendocrine tumors (NETs) are rare neoplasms characterized by a low proliferative index and, in some cases, a favorable prognosis. These tumors often overproduce and release biologically active substances that are responsible for severe syndromes. Tumor marker measurement provides the clinician with useful information for the management of NET patients. The substances released by overproducing tumors are currently used as biomarkers, but there is a need for sensitive markers also for the "biochemically silent" NETs. The most effective and reliable blood marker available today is chromogranin A (CgA). Because of its high sensitivity and specificity, this glycoprotein can be used for the diagnosis, prognosis and followup of NETs. Furthermore, CgA measurement can be used for monitoring those tumors not over-producing or releasing any hormones or biological amines. This paper is a synthetic review on the value of CgA in NET management and reports our experiences with CgA measurement in NET patients.

The genome of chemorefractory chronic lymphocytic leukemia reveals frequent mutations of NOTCH1 and SF3B1.

Next-generation whole-exome sequencing has revealed two novel genes, namely NOTCH1 and SF3B1, whose mutations predict poor outcome and preferentially associate with chemorefractory chronic lymphocytic leukemia (CLL). Analysis of 539 CLL cases documents that NOTCH1 mutations i) represent one of the most frequent cancer gene mutations involved at presentation; ii) cluster with cases harboring trisomy 12 and tend to be mutually exclusive with TP53 disruption among genetic subgroups; iii) identify high-risk patients showing poor survival similar to that associated with TP53 abnormalities; and iv) exert a prognostic role independent of widely accepted clinical and genetic risk factors. Mutations of SF3B1, a splicing factor that is a critical component of the spliceosome, recurrently associate with fludarabine-refractory CLL, occur at a low rate at CLL presentation and have a minor role in Richter transformation, corroborating the notion that CLL histological shift is molecularly distinct from chemorefractory progression without the Richter transformation.

Phase I clinical and pharmacokinetic study of trabectedin and cisplatin in solid tumours.

AIM OF THE STUDY: To define the maximum tolerated dose (MTD) and toxicity of trabectedin (T) and cisplatin (C) given on days 1 and 8 every 3 weeks to adult patients with advanced solid tumours. Plasma pharmacokinetics at cycle 1 and a preliminary anti-tumour activity assessment in ovarian and non-small cell lung cancer (OC, NSCLC) were secondary objectives. METHODS: In the dose finding part (DFP) of the study the dose of T given at each administration was escalated by 100 microg/m(2) increments from 300 microg/m(2) up to the MTD, with a fixed dose of C of 40 mg/m(2). The recommended dose (RD) was assessed in the previously treated and untreated OC and NSCLC patients in the expansion of the RD (ERD) part of the study. T was administered with corticosteroids pre-medication as 3-h infusion and C as 30-min infusion. RESULTS: Thirty-nine patients were treated in the DFP and 10 in the ERD. The MTD of T was 700 microg/m(2) due to dose-limiting neutropaenia and the RDs in the previously treated/untreated patients were 500 and 600 microg/m(2), respectively. Most common toxicities were nausea/vomiting (67%), asthenia/fatigue (55%) and reversible ASAT/ALAT elevation (51%). Time to recovery from myelosuppression was dose-dependent and treatment could be repeated after > or = 4 weeks in the majority of patients at 600 microg/m(2). Confirmed partial responses were observed in 4 of 13 evaluable OC patients and in 1 with uterine leiomyosarcoma. No pharmacokinetic interaction was observed. CONCLUSION: The administration of T and C on days 1 and 8 resulted in prolonged neutropaenia requiring treatment delay. The evaluation of a single every 3 week schedule is worthwhile because of the hints of anti-tumour activity observed in OC.

Phase I clinical and pharmacokinetic study of trabectedin and doxorubicin in advanced soft tissue sarcoma and breast cancer.

The combination of trabectedin (T) and doxorubicin (D) was brought into clinical development in soft tissue sarcoma (STS) and advanced breast cancer (ABC) because of its in vitro and in vivo additive anti-tumour effect, the fact that there are no overlapping toxicities and the anti-tumour activity of T in those tumours. Feasibility and anti-tumour activity of T+D administered every 3 weeks were evaluated in 38 patients (STS=29, ABC=9) untreated for advanced disease. D was given at 60 mg/m(2) and T at escalating doses from 600 to 800 microg/m(2), which was the maximum tolerated dose due to dose-limiting febrile neutropenia and asthenia. The recommended dose--given to 18 patients in total--was 700 microg/m(2) T with 60 mg/m(2) D. The pharmacokinetic profile of T and D at cycle 1 was analysed in 20 patients. The most common toxicities included a severe but reversible ASAT/ALAT increase (94%), nausea/vomiting, neutropenia, asthenia/fatigue, stomatitis. Partial response and stable disease were assessed in 18% and 56% of STS patients and in 55% and 33% of ABC patients. No pharmacokinetic interaction between T and D was observed. The lack of cumulative toxicity and related complications and the promising activity in STS support further development of T+D.

Phase I study of bortezomib with weekly paclitaxel in patients with advanced solid tumours.

BACKGROUND: The combination of a proteasome inhibitor with a taxane has potential clinical synergism that prompted a clinical test. PATIENTS AND METHODS: The maximum tolerated dose (MTD) and recommended dose (RD) of intravenous (i.v.) Bortezomib (B) (days 1, 4, 8, 11) and i.v. Paclitaxel (PTX) (days 1, 8) every 3 weeks was evaluated in patients with advanced solid tumours. The RD was tested in patients with breast, ovarian and prostate cancer. At the RD, microarray analysis of transcriptional profiles was carried out before and after the first dosing in peripheral blood mononuclear cells (PBMC). RESULTS: Thirty-one patients were enrolled and 22 were treated at the RD that corresponded to B 1.3mg/m(2) and PTX 100mg/m(2). The main toxicity was cumulative peripheral neuropathy (76% of patients; grade 3-4 in 9%) that required treatment discontinuation in six patients, followed by diarrhoea (55%) and fatigue (41%). Nine partial responses (30%) were observed (three breast cancer, four ovary, two prostate patients). Significant (p<0.05) and consistent changes (>70% of patients) in transcriptome were observed. CONCLUSIONS: The incidence of peripheral neuropathy and the anti-tumour activity comparable to that of single-agent PTX do not support further development of this regimen.

Phase I clinical study of the novel epothilone B analogue BMS-310705 given on a weekly schedule.

BACKGROUND: BMS-310705, a water-soluble semi-synthetic analogue of epothilone B, was selected for clinical development because of its in vivo anti-tumour activity and toxicity profile similar to that of ixabepilone, currently the most extensively evaluated and promising epothilone B analogue. The improved solubility of BMS-310705 allowed a cremophore-free formulation that avoided the need for pre-medication. PATIENTS AND METHODS: Two schedules were tested, one with drug administrations on days (D) 1, 8 and 15 followed by 1-week's rest, the other with administrations on D1 and 8 (D1&8 schedule) followed by 1-week's rest. Treatment was given as a 15-min infusion without pre-medication against hypersensitivity. The plasma pharmacokinetics of BMS-310705 was studied in 30 patients. An accelerated titration design 2B was applied for dose escalations. Twenty-seven patients were accrued in the D1, 8, 15 and 32 in the D1&8 schedule. RESULTS: The dose was escalated from 5-30 mg/m(2)/week with diarrhoea as dose-limiting toxicity; 15 and 20 mg/m(2) were the recommended doses in the D1, 8, 15 and D1&8 schedule, respectively. Other frequent non-haematological toxicities were neurotoxicity, mainly paraesthesia, asthenia and myalgia. Preliminary results showed linear pharmacokinetics along the range of doses tested with a short half-life. Five objective responses were reported. CONCLUSIONS: Further clinical development of BMS-310705 might be worthwhile in solid tumours where ixabepilone or other epothilones are not indicated.

Concerted escalation of dose and dosing duration in a phase I study of the oral camptothecin gimatecan (ST1481) in patients with advanced solid tumors.

BACKGROUND: Gimatecan is an orally bioavailable camptothecin analogue with preclinical findings of promising antitumor activity. A phase I design of concerted dose escalation and dosing duration was implemented to assess the potential schedule dependency of tolerability that emerged from animal studies. PATIENTS AND METHODS: Gimatecan was given daily for five consecutive days per week for 1, 2 or 3 weeks every 28 days. Plasma levels of total gimatecan were measured on the first and the last day of treatment in each schedule. RESULTS: Overall, 108 patients were treated with 0.8-7.2 mg/m(2) of gimatecan per cycle. The main toxicity was myelosuppression with dose-limiting thrombocytopenia. In the 1-, 2- and 3-week schedule, the maximum tolerated doses were 4.5, 5.6 and 6.4 mg/m(2). Diarrhea and asthenia were of low grade and of minor clinical relevance, while the higher incidence of nausea and vomiting in the 1-week schedule required the use of antiemetic prophylaxis. Due to the prolonged half-life (approximately 77 h), the plasma concentration of gimatecan increased from the first to the last day of dosing. Six partial responses were observed. CONCLUSIONS: Tolerability of gimatecan was schedule dependent. Further testing with schedules taking into account its long persistence in human plasma is worthwhile.

Simple identification of dominant p53 mutants by a yeast functional assay.

Analysis of families with germline p53 mutations shows that the mutant p53 allele behaves as a dominant oncogene at the genetic level, although it behaves as a recessive oncogene at the cellular level, since tumours invariably show mutation or loss of both wild-type alleles. At the biochemical level it is possible that some clinically important mutant p53 proteins may be carcinogenic through a dominant mechanism. We show that p53 mutants can be readily classified according to their dominant potential using a simple yeast functional assay. Wild-type p53 is constitutively expressed from a TRP1 vector, p53 mutants are expressed from an otherwise identical LEU2 vector and net transcriptional activity is scored using an ADE2-based reporter. Twenty seven p53 mutants were tested: 19 were recessive, i.e. gave white colonies, and eight showed dominant activity, i.e. gave pink/red colonies. This simple assay should facilitate studies on p53 dominance.

A randomized phase II study of combination, alternating and sequential regimens of doxorubicin and docetaxel as first-line chemotherapy for women with metastatic breast cancer.

BACKGROUND: This randomized phase II study was conducted to evaluate the efficacy of doxorubicin and docetaxel (DOC) administered either as a combination, an alternating or a sequential regimen in women with metastatic breast cancer. Secondary objectives included overall response, time to progression, survival and safety. PATIENTS AND METHODS: Patients with breast cancer (n=123) were randomized to receive doxorubicin and DOC either in combination (60 mg/m2 of each drug), or by alternated or sequential schedule (100 mg/m2 DOC and 75 mg/m2 doxorubicin) every 3 weeks for a maximum of eight cycles as first chemotherapy for stage IV disease. A second randomization allocated patients from each arm to receive prophylactic oral ciprofloxacin or no therapy to prevent febrile neutropenia. RESULTS: Patients received a median of eight cycles. In an intention-to-treat analysis, the overall response was 63%, 52% and 61% in the combination, alternating and sequential schedules, respectively. Corresponding rates of complete response were 15%, 14% and 11%. Grade 4 neutropenia was common in all arms (81%) and, together with febrile neutropenia, was significantly more frequent with the combination. Prophylaxis with ciprofloxacin did not reduce the incidence of febrile neutropenia or infection. Other frequent non-hematological adverse events included alopecia, nausea, vomiting, stomatitis and asthenia. Congestive heart failure only occurred in the combination arm (10%). CONCLUSION: All three schedules are feasible and endowed of good therapeutic activity. In view of the more pronounced toxicity and the risk of cardiac events because of the higher exposure to doxorubicin, the combination should be least favored when treating women with metastatic breast cancer. Prophylaxis with ciprofloxacin was ineffective and is not recommended.