A phase 3 open-label, randomized, multicenter study of Imprime PGG in combination with cetuximab in patients with KRAS wild type metastatic colorectal cancer

TPS787

Background: Imprime PGG (Imprime) is a novel immune modulator (complex carbohydrate biologic), which harnesses innate immune cells to enhance killing of antibody-targeted tumor cells. In a phase 2 single-arm clinical trial in mCRC, the combination of Imprime with cetuximab resulted in 24% ORR, 62% disease control rate (DCR), and median time to progression (TTP) of 12 wks (Tamayo ME, Ann Onc 2010), representing approximate 100% increases vs historical control (Cunningham, NEJM 2004). ORR was 45%, DCR, 82% and TTP, 24 wks in pts with KRAS WT tumors (post hoc analysis). Single-agent cetuximab has been shown to improve objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) in patients (pts) with epidermal growth factor receptor (EGFR) expressing, KRAS wild-type (WT) metastatic colorectal cancer (mCRC) who failed oxaliplatin- and irinotecan-based therapy or are intolerant to irinotecan. The mechanism of action of cetuximab is thought to rely on competitive blockade of endogenous ligand binding and downstream signaling, internalization and down regulation of EGFR, as well as antibody-dependent cellular cytotoxicity (ADCC) (Erbitux SmPC). The current trial, sponsored by Biothera (registered with ClinicalTrials.gov NCT01309126) is to confirm these findings in phase 3. Methods: Eligible pts will have had prior oxaliplatin- and irinotecan-based therapy or be intolerant to irinotecan, and will meet key inclusion criteria including measurable disease and ECOG performance status of 0 or 1. In a 2:1 randomization, stratified by geographic region, prior chemotherapy and site, approximately 795 pts will receive weekly open-label Imprime plus cetuximab or cetuximab alone. The primary endpoint of the study is OS and primary analysis will occur when ~709 deaths have occurred. Secondary endpoints include PFS, ORR (based on RECIST 1.1), quality of life, safety and pharmacokinetics. Exploratory endpoints include biomarker analyses. Pt screening and enrollment is underway in the United States and Europe. Clinical trial information: NCT01309126.

Phase Ib study of PGG beta glucan in combination with anti-MUC1 antibody (BTH1704) and gemcitabine for the treatment of advanced pancreatic cancer

TPS493

Background: Mucin 1 (MUC1) is a tumor associated membrane-bound glycoprotein that promotes oncogenesis through promotion of epithelial cell polarity loss, anti-apoptosis, and hypoxia driven angiogenesis. MUC1 overexpression is associated with aggressive behavior and poor outcomes in pancreatic ductal adenocarcinoma (PDAC), and increased resistance to gemcitabine (G) in vitro. BTH1704 (BTH) is a humanized monoclonal antibody (MAb) targeting aberrantly glycosylated MUC1. Imprime PGG (PGG) is a soluble yeast-derived b 1,3/1,6 glucan that binds complement receptor 3 (CR3) on innate immune cells priming them to exert anti-tumor activity against complement (iC3b) opsonized tumor cells. Following incubation of PGG with whole blood from healthy subjects, variability in PGG binding to neutrophils and monocytes has been observed, with higher binding and functional changes correlating with higher levels of endogenous anti-b glucan antibodies. BTH binds to antigens (MUC1), leading to iC3b opsonization of tumor cells thus, allowing PGG-primed leukocytes to kill the iC3b-opsonized tumor cells. This forms the rationale for testing BTH1704 combined with G + PGG. Methods: This is a single institution Phase 1b dose escalation study with a standard 3x3 design to determine the maximal administered dose (MAD) of BTH combined with G + PGG in patients with previously treated advanced PDAC.Each dose cohort includes at least one subject with high and one low PGG binding capability. Primary objectives: establish MAD of BTH combined with G + PGG. Secondary objectives: characterize adverse effects, clinical response, time to progression, progression free and overall survival. Correlative objectives: quantify PGG binding, MDSC phenotyping of PBMC, anti b glucan antibody levels, MUC1 IHC. Inclusion criteria: confirmed advanced PDAC, ECOG PS 0-2, rest period 2-6 weeks from prior first- or second-line treatment. Exclusion criteria: uncontrolled chronic illness. Administration and design: BTH and PGG are administered on days 1, 8, 15, and 22 of a 28-day cycle; G is administered on days 1, 8, and 15. The study is currently enrolling patients. Clinical trial information: NCT02132403. Clinical trial information: NCT02132403.

Incidence of osteonecrosis of the jaw in patients receiving denosumab or zoledronic acid for bone metastases from solid tumors or multiple myeloma: Results from three phase III trials

9640

Background: In patients with metastatic bone disease (MBD), the use of antiresorptive therapies such as denosumab or zoledronic acid (ZA) reduces the risk of skeletal-related events but is associated with a small risk of osteonecrosis of the jaw (ONJ). Two phase 3 clinical trials of denosumab vs ZA in patients with MBD showed overall cumulative ONJ incidences to be 3.8% to 4.7% at approximately 5 years of treatment with denosumab across blinded and open-label extension phases. ONJ associated with ZA was only assessed in the blinded treatment phases, as patients switched to denosumab once superior efficacy was demonstrated. Here we report incidence rates of ONJ by first vs subsequent years of exposure for the blinded treatment phase of all three phase III clinical trials. Methods: Patients (n = 5,677) with bone metastases from solid tumors or multiple myeloma received either SC denosumab 120 mg and IV placebo or IV ZA 4 mg (adjusted for renal function) and SC placebo Q4W in the double-blinded treatment phase of each trial. Patients who received ≥ 1 active dose during the blinded treatment phase were included in this analysis for up to 44.5 months of denosumab exposure and 41.3 months of ZA exposure. Oral assessments were conducted at baseline and every 6 months thereafter by the investigator or other qualified examiner. Potential ONJ events were independently adjudicated by a blinded committee of experts. Results: The median (Q1, Q3) time to onset of ONJ was similar in both treatment groups (15.6 [9.5, 20.0] months for denosumab, 15.8 [11.0, 23.6] months for ZA). Cumulative incidence rates of ONJ during the blinded treatment phases for all three trials by patient-years of follow-up are shown below (Table). Conclusions: The incidence of ONJ increased with longer duration of antiresorptive exposure. There were no significant differences between treatment groups in ONJ incidence at year 1 or beyond. Clinical trial information: NCT00321464; NCT00330759; NCT00321620. [Table: see text]

Denosumab versus placebo as adjuvant treatment for women with early-stage breast cancer who are at high risk of disease recurrence (D-CARE): An international, randomized, double-blind, placebo-controlled phase III clinical trial

TPS670

Background: Bone is a common site of distant recurrence in women with early-stage breast cancer, and represents approximately 40% of all first recurrences. Tumor cells in bone release growth factors and cytokines that stimulate osteoclast-mediated bone resorption through the RANK ligand (RANKL) pathway. In preclinical studies, RANKL inhibition significantly delays skeletal tumor formation, reduces skeletal tumor burden, and prolongs survival of tumor-bearing mice. Denosumab is a fully human monoclonal antibody that binds to RANKL with high affinity and specificity. It is approved for the prevention of skeletal-related events in patients with established bone metastases from a variety of solid tumors. The purpose of the D-CARE trial is to evaluate the ability of denosumab to prolong bone metastasis-free survival (BMFS) and disease-free survival (DFS) in the adjuvant breast cancer setting. Methods: Approximately 4,500 women with stage II or III breast cancer, at high risk for recurrence and with known hormone and HER-2 receptor status, are eligible. Standard-of-care adjuvant or neoadjuvant chemo-, endocrine, or HER-2 targeted therapy, alone or in combination must be planned. Exclusion criteria include: a prior history of breast cancer (except DCIS or LCIS) or distant metastasis, oral bisphosphonate (BP) use within 1 year of randomization or any intravenous BP use. Patients are randomized 1:1 to receive denosumab 120 mg or placebo subcutaneously monthly for 6 months, then every 3 months for a total of 5 years of treatment. All patients receive vitamin D (≥ 400 IU) and calcium (≥ 500 mg) supplements. Primary endpoint of this event-driven trial is BMFS. Secondary endpoints include DFS and overall survival. Safety, quality of life assessments, breast density, and biomarkers are additional endpoints. The trial, sponsored by Amgen Inc. and registered with the ClinicalTrials.gov identifier NCT01077154, began enrolling patients in June 2010 and is expected to complete in October 2016. Paul Goss and Dianne Finkelstein supported in part by the Avon Foundation New York.

Health state preferences associated with subcutaneous injections and intravenous infusions for treatment of bone metastases

e16528

Background: Although cost utility models are often used to estimate the value of treatments for metastatic cancer, limited information is available on the utility of common treatment modalities. Bisphosphonate treatment for bone metastases (BM) is frequently administered via intravenous (IV) infusion, while a recently approved treatment to prevent skeletal-related events (SREs) of BM is administered as a subcutaneous (SC) injection. This study estimated the impact of these treatment modalities on health state (HS) preference. Methods: Participants from the UK general population completed time trade-off interviews to assess the utility of HS vignettes. Respondents first rated a HS representing cancer with BM. Subsequent HSs added descriptions of treatment modalities (ie, injection or infusion) to this basic HS. To represent a range of possible treatment experiences, the two treatment modalities were presented with and without chemotherapy (chemotx), and infusion characteristics were varied by duration (30 minutes or 2 hours) and renal monitoring. Results: A total of 121 participants completed the interviews (47.9% male, 76.9% white). Cancer with BM had a mean utility of 0.40 on a standard utility scale (1 = full health; 0 = death). Adding an injection resulted in a mean utility decrease (ie, disutility) of -0.004. The 30 minute and 2 hour infusions had mean disutilities of -0.02 and -0.04, respectively. Mean disutility of the 30 minute infusion was greater with renal monitoring (-0.05 with same-day blood draw; -0.07 with blood draw 2 days prior). Chemotx was associated with substantial disutility (-0.17). For the HS of BM with chemotx, the mean disutilities of injection, 30 minute infusion, and 2 hour infusion, were -0.02, -0.03, and -0.04, respectively. Disutility associated with injection was significantly smaller than the disutility of both the 30 minute and 2 hour infusions (p < 0.05), regardless of chemotx status. Conclusions: Respondents perceived an inconvenience with each type of BM treatment, but injections were preferred over infusions. The resulting utilities may be used in cost utility models examining the value of treatments for the prevention of SREs in patients with BM.

Transmembrane and soluble isoforms of heparin-binding epidermal growth factor-like growth factor regulate distinct processes in the pancreas

BACKGROUND & AIMS

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is produced as a type-I, single-pass transmembrane protein that can be cleaved to release a diffusible peptide. HB-EGF, often overexpressed in damaged or diseased epithelium, is normally expressed in pancreatic islets, but its function is not understood.

METHODS

To understand the function of each isoform of HB-EGF, we made transgenes expressing either a constitutively transmembrane or a constitutively secreted protein.

RESULTS

The transmembrane isoform was not an inert precursor protein, but a functional molecule, downregulating the glucose-sensing apparatus of pancreatic islets. Conversely, the secreted form of HB-EGF improved islet function, but had severe fibrotic and neoplastic effects on surrounding tissues. Each isoform had a more severe phenotype than that of full-length HB-EGF, even though the full-length protein was efficiently cleaved, thus producing both isoforms, suggesting that a level of regulation was lost by separating the isoforms.

CONCLUSIONS

This work demonstrates that islet function depends on the ratio of cleaved to uncleaved HB-EGF and that the transmembrane intermediate, while deleterious to islet function, is necessary to restrict action of soluble HB-EGF away from surrounding tissue.

New systemic frontline treatment for metastatic colorectal carcinoma

Options for first-line chemotherapy in patients with metastatic colorectal carcinoma have broadened considerably with the introduction of irinotecan and oxaliplatin. Furthermore, the oral fluoropyrimidine capecitabine has demonstrated efficacy in Phase III trials and recently was approved for first-line treatment in Europe and the United States. Capecitabine yielded similar median times to disease progression and median survival rates compared with bolus 5-fluorouracil (5-FU)/leucovorin (LV) (Mayo Clinic/North Central Cancer Treatment Group regimen), with superior and similar response rates, respectively. However, its role as a first-line, single-agent substitute for intermittent infusional 5-FU/LV remains to be defined. The addition of irinotecan or oxaliplatin to 5-FU/LV resulted in improved response rates and progression-free survival in large, randomized trials; moreover, irinotecan-containing regimens resulted in improved overall survival. Prevalent regimens of irinotecan/5-FU/LV and oxaliplatin/5-FU/LV have been compared in two randomized Phase III trials. One study demonstrated the statistical superiority of oxaliplatin/infusional 5-FU/LV over irinotecan/bolus 5-FU/LV in terms of response, time to disease progression, and median survival; however, those advantages may have been attributable to infusional administration or to major differences in second-line therapy. A randomized Phase III study comparing irinotecan and oxaliplatin in combination with the same infusional 5-FU/LV regimens and crossover in case of disease progression showed equivalent efficacy for both schedules in the first-line setting, but the irinotecan combination proved beneficial in terms of safety. New molecular targeted agents, such as angiogenesis-modulating compounds (e.g., bevacizumab) and epidermal growth factor receptor inhibitors (e.g., cetuximab), are under clinical investigation. This review updates current systemic frontline treatments and future perspectives for patients with advanced colorectal carcinoma.

Phase I study of the humanized antiepidermal growth factor receptor monoclonal antibody EMD72000 in patients with advanced solid tumors that express the epidermal growth factor receptor

PURPOSE

To investigate the safety and tolerability and to explore the pharmacokinetic and pharmacodynamic profile of the humanized antiepidermal growth factor receptor monoclonal antibody EMD72000 in patients with solid tumors that express epidermal growth factor receptor (EGFR).

PATIENTS AND METHODS

This was a phase I dose-escalation trial of EMD72000 in patients with advanced, EGFR-positive, solid malignancies that were not amenable to any established chemotherapy or radiotherapy treatment. EMD72000 was administered weekly without routine premedication until disease progression or unacceptable toxicity.

RESULTS

Twenty-two patients were treated with EMD72000 at five different dose levels (400 to 2,000 mg/wk). National Cancer Institute common toxicity criteria grade 3 headache and fever occurring after the first infusion were dose limiting at 2,000 mg/wk; thus, the maximum-tolerated dose was 1,600 mg/wk. No other severe side effects, especially no allergic reactions or diarrhea, were observed. Acneiform skin reaction was the most common toxicity, but it was mild, with grade 1 in 11 patients (50%) and grade 2 in three patients (14%). Pharmacokinetic analyses demonstrated a predictable pharmacokinetic profile for EMD72000. Pharmacodynamic studies on serial skin biopsies revealed that EMD72000 effectively abrogated EGFR-mediated cell signaling (eg, reduced phosphorylation of EGFR and mitogen-activated protein kinase), with no alteration in total EGFR protein. Objective responses (23%; 95% CI, 8% to 45%) and disease stabilization (27%; 95% CI, 11% to 50%) were achieved at all dose levels, and responding patients received treatment for up to 18 months without cumulative toxicity.

CONCLUSION

Treatment with EMD72000 was well tolerated and showed evidence of activity in heavily pretreated patients with EGFR-expressing tumors. EMD72000 at the investigated doses significantly inhibited downstream EGFR-dependent processes.