Global, multicenter, randomized, phase II trial of gemcitabine and gemcitabine plus AGS-1C4D4 in patients with previously untreated, metastatic pancreatic cancer

BACKGROUND

We evaluated AGS-1C4D4, a fully human monoclonal antibody to prostate stem cell antigen (PSCA), with gemcitabine in a randomized, phase II study of metastatic pancreatic cancer.

PATIENTS AND METHODS

Patients with Eastern Cooperative Oncology Group (ECOG) performance status 0/1 and previously untreated, metastatic pancreatic adenocarcinoma were randomly assigned 1:2 to gemcitabine (1000 mg/m(2) weekly seven times, 1 week rest, weekly three times q4weeks) or gemcitabine plus AGS-1C4D4 (48 mg/kg loading dose, then 24 mg/kg q3weeks IV). The primary end point was 6-month survival rate (SR). Archived tumor samples were collected for pre-planned analyses by PSCA expression.

RESULTS

Between April 2009 and May 2010, 196 patients were randomly assigned to gemcitabine (n = 63) or gemcitabine plus AGS-1C4D4 (n = 133). The 6-month SR was 44.4% (95% CI, 31.9-57.5) in the gemcitabine arm and 60.9% (95% CI, 52.1-69.2) in the gemcitabine plus AGS-1C4D4 arm (P = 0.03), while the median survival was 5.5 versus 7.6 months and the response rate was 13.1% versus 21.6% in the two arms, respectively. The 6-month SR was 57.1% in the gemcitabine arm versus 79.5% in the gemcitabine plus AGS-1C4D4 arm among the PSCA-positive subgroup and 31.6% versus 46.2% among the PSCA-negative subgroup.

CONCLUSIONS

This randomized, phase II study achieved its primary end point, demonstrating an improved 6-month SR with addition of AGS-1C4D4 to gemcitabine among patients with previously untreated, metastatic pancreatic adenocarcinoma. ClinicalTrials.gov identifier: NCT00902291.

Injection Moulding of Rubber Compounds1

The aim of this study is to show the relevant physical parameters related to rubber injection moulding, and especially compressibility, vulcanisation and wall slippage. Three materials are studied: an SBR compound, without and with a lubricant, and an EPDM compound. The viscosity is determined by capillary rheometry. The modified SBR exhibits wall slippage. Rheological vulcanisation kinetics are determined with a Moving Die Rheometer. Precise moulding experiments are carried out with an injection moulding machine and a mould equipped with pressure and temperature transducers. At low flow rate, the influence of the curing reaction on the pressure appears clearly especially for the fast curing EPDM. The conditions in which surface scorch defects appear are determined. The SBR with lubricant needs a lower pressure to fill the cavity than without lubircant. A model of mould filling is developed. The material is purely viscous, with a state of cure dependence of the viscosity. A Norton friction law is introduced to take into account a possible slippage at the cavity walls. A compressible calculation in the injection chamber allows a realistic evaluation of the flow rate at the entry of the cavity. The comparison with the experimental data confirms the importance of the compressibility, and the influence of the vulcanisation on the viscosity at low flow rate. In moulding conditions for which vulcanisation is not activated during the filling stage, despite uncertainties on the friction law parameters appropriate to the cavity wall roughness, the agreement with experiments is better when wall slippage is taken into account.

Elastic Calculation of Residual Stresses in Injection Molding

A calculation of residual stresses in injection molding using a 2-D description of the geometry is presented. The polymer follows an elastic behavior law. The thermal shrinkage and the frozen-in pressure when a layer solidifies are taken into account. A calculation of the pressure in the liquid areas after the gate is frozen is presented. A simplified mold deformation model is introduced and its influence on residual stresses is shown. Results are presented for a polystyrene injected in a square plaque.

Injection Molding of Reinforced Thermosets

The orientation of glass fibers (initial length 20 mm) and the mold filling of reinforced unsaturated polyester compounds have been studied. Observations of the fiber orientation have been made in three molds where shear and elongational flows occur in variable ways. A part of the fibers are split and broken into filaments. Reinforcement can be more or less buckled. A thin skin layer without fibers is observed. The great thickness of a core region with an orientation perpendicular to the flow direction shows the importance of negative elongational flows. Efficiency of positive elongational flows to suppress buckling and to give a well flow aligned orientation is also observed. On the contrary the efficiency of shear flows is limited compared to elongational flows. The incidence of injection conditions on the pressure inside a rectangular plaque has been studied both experimentally and theoretically. Experimental difficulties due to the material heterogeneity leads to measure viscosity data of the uncured material on a special capillary rheometer and rheological kinetic data on a simplified compound. Numerical results are in good agreement with experimental measurements. For instance the effect of crosslinking which leads to a pressure rise at low flow rate or high mold temperature is well predicted.

Flow and Fiber Orientation Calculations in Reinforced Thermoplastic Extruded Tubes

A calculation of fiber orientation of reinforced thermoplastics in two tube die geometries is presented. The flow field and fiber motion are calculated using coupled anisotropic constitutive equation and equation of change for fiber orientation. A finite element method is used for the flow field computation, and a simplified characteristic method for the fiber orientation. Results show that fibers orient parallel to the tube axis in a classical die of constant radius in the final land whereas fibers have a more isotropic orientation in a die with a final divergent land. Experimental observations and quantification of fiber orientation in reinforced thermoplastic tubes extruded with the two dies are presented. Results of the calculation agree well with the experimental data for the classical die. For the diverging die, the agreement is good at the tube surface, but the calculation underestimates the degree of orientation perpendicular to the tube axis in the core of the tube.

External Calibration in PA12 Tube Extrusion

Elongation at break is one of the major end-use properties of polyamide 12 extruded tubes. It is strongly affected by the tube microstructure and the molecular orientation resulting from extrusion conditions. Molecular orientation was characterized by X-ray diffraction and birefringence evaluation in light microscopy. Measurements were carried out on (r, z) sections obtained by polishing and microtoming. On the other hand, polymer drawing was measured on line by tracer techniques. Calibration stage was determined as the key step of the process that generates orientation in tubes: as the tube is drawn through a cylindrical calibrator under vacuum and cooled from its outside surface, calibration leads to a highly oriented zone in the twenty external microns. Calibration conditions and elongation at break have been connected through orientation level in this region. Molecular orientation was found to strongly depend on the draw ratio in the calibration tank. Finally, birefringence of the tube external layers and elongation at break were successfully correlated. Elongation at break can be enhanced by reducing orientation resulting from calibration conditions.

External Calibration in PA12 Tube Extrusion

In PA12 tube extrusion, calibration or sizing is the key step of the process that affects subsequent mechanical properties. The extruded tube is pulled through a cylindrical calibrator under vacuum. A water flow rate is applied at the inner side of the calibrator, creating a lubricant water layer at the polymer outer surface. The scope of this article is to show how this lubrication influences the elongation at break of tubes through drawing kinematics of the polymer. Lubricant water layer thickness measurements and on-line video recording have been employed to monitor the lubrication dependence of the velocity profiles from the extruder die to the end of calibrator. Velocities were measured through three independent innovative methods and thirty-two calibration conditions have been carried out to validate our work. Three main calibration parameters were found to determine the water layer thickness: the level of vacuum applied in the calibration tank, the water flow rate at the calibrator entrance, and the line speed. The influence of each parameter on lubrication level was found out. Simultaneously, the draw ratio in the calibration tank was deduced from velocity profiles. This parameter was found to affect tensile properties and to depend strongly on the level of lubrication during calibration. We showed quantitatively that rising the water layer thickness leads to a diminution of the draw ratio in the calibration tank and an increase of the elongation at break. This implies that we are now able to optimize tensile properties by fitting the main calibration parameters to improve lubrication and restrict draw ratio in the calibration tank.

Treatment of diabetic ketoacidosis with subcutaneous insulin lispro: a review of the current evidence from clinical studies

AIM

Low-dose intravenous infusions of regular insulin, usually initiated in the emergency department and continued in the intensive care unit (ICU), are the standard care for patients with diabetic ketoacidosis (DKA) to ensure rapid resolution of hyperglycaemia and ketoacidosis. Several studies have evaluated whether subcutaneous injections of the rapid-acting analogue insulin lispro may be an alternative to intravenous insulin infusion for avoiding ICU admissions of uncomplicated DKA cases.

METHODS

This review summarizes the current clinical evidence for the effectiveness and safety of subcutaneous insulin lispro injections in non-severe DKA patients. Relevant studies were identified by a systematic literature search through the PubMed database.

RESULTS

To date, four small randomized studies (156 patients overall; three studies in adults and one in paediatric patients with diabetes) have directly compared subcutaneous insulin lispro injections every 1-2h vs continuous intravenous infusions of regular insulin. Patients with severe complications were excluded. In all studies, the mean time to resolution of DKA was similar in both treatment groups [range (three studies): lispro 10-14.8h; regular insulin 11-13.2h]. The mean time to resolution of hyperglycaemia, total insulin doses required, number of hospitalization days and number of hypoglycaemic episodes were similar in both treatment groups; no severe complications or DKA recurrences were reported, and one study showed a 39% cost reduction for the insulin lispro group.

CONCLUSION

In patients with mild-to-moderate DKA, subcutaneous injections of insulin lispro every 1-2h offer a feasible alternative to continuous intravenous infusions of regular insulin, and should now be evaluated in larger, more appropriately powered studies.

A phase I/IIA study of AGS-PSCA for castration-resistant prostate cancer

BACKGROUND

This first-in-human phase I/IIA study was designed to evaluate the safety and pharmacokinetics (PKs) of AGS-PSCA a fully human monoclonal antibody directed to prostate stem cell antigen (PSCA) in progressive castration-resistant prostate cancer.

PATIENTS AND METHODS

Twenty-nine patients were administered infusions of AGS-PSCA (1-40 mg/kg) every 3 weeks for 12 weeks; 18 final patients received a 40-mg/kg loading dose followed by 20-mg/kg repeat doses. Primary end points were safety and PK. Immunogenicity, antitumor activity and circulating tumor cells were also evaluated.

RESULTS

No drug-related serious adverse events were noted. Dose escalation stopped before reaching the maximum tolerated dose as target concentrations were achieved. Drug levels accumulated linearly with dose and the mean terminal half-life was 2-3 weeks across dose levels. The 40-mg/kg loading dose followed by repeated 20-mg/kg doses yielded serum drug concentrations above the projected minimum therapeutic threshold after two to three doses without excessive drug accumulation or toxicity. Significant antitumor effects were not seen.

CONCLUSIONS

A 40-mg/kg loading dose followed by 20-mg/kg infusions every 3 weeks is the recommended phase II dose of AGS-PSCA. PSCA is a promising drug target and studies in prostate and other relevant solid tumors are planned.

Long-acting somatostatin analogues decrease blood transfusion requirements in patients with refractory gastrointestinal bleeding associated with angiodysplasia

BACKGROUND

Gastrointestinal angiodysplasias (GIADs) may be the cause of recurrent bleeding, despite endoscopic treatment.

AIM

To evaluate the effect of long-acting somatostatin analogues on blood transfusion requirements, in patients with refractory bleeding due to GIADs.

METHODS

Consecutive patients with recurrent bleeding from GIADs were enrolled. They received somatostatin analogue treatment for at least 6 months. The efficacy was evaluated in terms of blood transfusions, frequency of bleeding episodes and haemoglobin level during 6 months of treatment (Period During) compared to a 6-months' period before treatment (Period Before).

RESULTS

Fifteen patients were enrolled from 2007 to 2010. The median duration of somatostatin analogue treatment was 12 months (range: 6-36). The number of transfusions significantly decreased in Period During compared with Period Before [median number: 2 (0-14) vs. 10 (6-24); P < 0.001]. The percentage of patients who experienced a bleeding event was lower during somatostatin analogues treatment (20% vs. 73%; P = 0.01). The mean haemoglobin level was significantly higher when somatostatin analogues were offered [median: 10 g/dL (9-13) vs. 7 (5-8.5); P < 0.001]. None of the patients discontinued treatment due to side effects.

CONCLUSIONS

Long-acting somatostatin analogues treatment decreased transfusion needs in patients with refractory bleeding from gastrointestinal angiodysplasias. Bleeding episodes were limited and haemoglobin improved during treatment. Long-acting somatostatin analogues may represent an option for the management of patients with chronic bleeding due to gastrointestinal angiodysplasias.

Neoadjuvant erlotinib and surgical resection of a stage iiia papillary adenocarcinoma of the lung with an L861Q activating EGFR mutation

The use of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) is evolving, as is an understanding of predictive biomarkers for tumour response in non-small-cell lung cancer (NSCLC). In this report, we describe a case of rapidly progressing, borderline-resectable, clinical stage IIIA (micro) papillary adenocarcinoma in a 78-year-old woman who experienced a profound response to neoadjuvant erlotinib without short-term toxicity. On EGFR mutation testing, this patient had an uncommon activating point mutation at L861Q in exon 21. Her response permitted successful surgical resection with negative margins and avoidance of chemoradiation, which she was deemed too frail to tolerate. Our case addresses unique management issues such as preoperative testing for EGFR mutation, utility of histology in predicting EGFR mutations, and use of EGFR-TKIs pre- and postoperatively for potentially resectable NSCLC.

[Analysis of asbestos bodies and nude fibres in the lung parenchyma of operated lung cancers. A retrospective monocentric study of 73 cases]

We report on a study concerning a retrospective monocentric series of 73 lung cancers operated on between July 2004 and December 2009. All patients had a mineralogical analysis of a sample of lung tissue combined with an occupational questionnaire. This combination enables us to suggest a declaration of occupational exposure in almost one third of cases. We suggest that a healthy parenchymal fragment is to be obtained by biopsy routinely in cases of lung cancer surgery. The analysis should be carried out if the occupational survey does not demonstrate any evident exposure and if the patient is not known to be presenting a pleuropulmonary disease following asbestos exposure (pleural plaques and asbestosis).

What are the factors that predict outcome at relapse after previous esophagectomy and adjuvant therapy in high-risk esophageal cancer?

OBJECTIVES

The present study investigated factors affecting outcome at relapse after previous surgery and adjuvant chemoradiation (crt) in high-risk esophageal cancer patients.

PATIENTS AND METHODS

From 1989 to 1999, we followed high-risk resected esophageal cancer patients who had completed postoperative crt therapy. Patients who relapsed with a disease-free interval of less than 3 months were treated with palliative crt when appropriate. Patients with a disease-free interval of 3 months or more were treated with best supportive care. Post-recurrence survival was estimated using the Kaplan-Meier technique, and statistical comparisons were made using log-rank chi-square tests and Cox regression.

RESULTS

Of the 69 patients treated with adjuvant crt after esophagectomy, 46 experienced recurrence. Median time to relapse was 28 months (range: 0.1-40 months). Among the 46 relapsed patients, median age was 61 years (range: 37-82 years), and 42 were men. At the initial staging, 44 of 46 were node-positive; 31 of 46 had adenocarcinoma. In 33 of 46, post-esophagectomy resection margins were clear. Median follow-up after recurrence was 30.5 months (range: 1.3-100 months). Median overall survival after recurrence was 5.8 months, and the 12-month, 24-month, and 36-month survival rates were 20%, 10%, and 5% respectively. Of the prognostic factors analyzed, only resection margin status and interval to recurrence were statistically significant for patient outcome in univariate and multivariate analysis. Patients who had positive resection margins and who relapsed 12 or fewer months after surgery and adjuvant crt had a median post-recurrence overall survival of 0.85 months as compared with 6.0 months in other patients (more than 12 months to relapse, or negative resection margins, or both; log-rank p = 0.003).

CONCLUSIONS

Resection margin status and interval to disease relapse are significant independent prognostic factors for patient outcome after adjuvant crt therapy.