Combined MTOR and autophagy inhibition: phase I trial of hydroxychloroquine and temsirolimus in patients with advanced solid tumors and melanoma

The combination of temsirolimus (TEM), an MTOR inhibitor, and hydroxychloroquine (HCQ), an autophagy inhibitor, augments cell death in preclinical models. This phase 1 dose-escalation study evaluated the maximum tolerated dose (MTD), safety, preliminary activity, pharmacokinetics, and pharmacodynamics of HCQ in combination with TEM in cancer patients. In the dose escalation portion, 27 patients with advanced solid malignancies were enrolled, followed by a cohort expansion at the top dose level in 12 patients with metastatic melanoma. The combination of HCQ and TEM was well tolerated, and grade 3 or 4 toxicity was limited to anorexia (7%), fatigue (7%), and nausea (7%). An MTD was not reached for HCQ, and the recommended phase II dose was HCQ 600 mg twice daily in combination with TEM 25 mg weekly. Other common grade 1 or 2 toxicities included fatigue, anorexia, nausea, stomatitis, rash, and weight loss. No responses were observed; however, 14/21 (67%) patients in the dose escalation and 14/19 (74%) patients with melanoma achieved stable disease. The median progression-free survival in 13 melanoma patients treated with HCQ 1200mg/d in combination with TEM was 3.5 mo. Novel 18-fluorodeoxyglucose positron emission tomography (FDG-PET) measurements predicted clinical outcome and provided further evidence that the addition of HCQ to TEM produced metabolic stress on tumors in patients that experienced clinical benefit. Pharmacodynamic evidence of autophagy inhibition was evident in serial PBMC and tumor biopsies only in patients treated with 1200 mg daily HCQ. This study indicates that TEM and HCQ is safe and tolerable, modulates autophagy in patients, and has significant antitumor activity. Further studies combining MTOR and autophagy inhibitors in cancer patients are warranted.

Results of a feasibility study of I-124 girentuximab in metastatic clear cell renal cell carcinoma (m ccRCC)

406

Background: Carbonic anhydrase IX (CAIX), a transmembrane glycoprotein with an intracellular enzymatic domain, is overexpressed in ccRCC as a result of VHL loss. Chimeric antibody girentuximab is a monoclonal antibody that binds an extracellular epitope of CAIX. Iodine radiolabeled (I-124) girentuximab can be used as a PET radiotracer and has been shown to identify ccRCC primary tumors with high sensitivity and specificity. This study was designed to test the feasibility of using I-124 girentuximab PET/CT in the m ccRCC setting and to produce preliminary data regarding the operating characteristics of these scans in m ccRCC. Methods: Patients (pts) with ccRCC refractory to standard antiangiogenic therapy were treated with brivanib (Bristol-Myers Squibb, Co.), a tyrosine kinase inhibitor of VEGFR2 and FGFR. Baseline I-124 girentuximab scans were obtained. For 1 pt, a second scan was performed after 8 weeks. Clinical outcome was measured radiographically by RECIST 1.0 and standard cross-sectional imaging. Results: 5 pts had 6 I-124 girentuximab PET/CT scans. No adverse events occurred. 17 RECIST target lesions were identified at baseline. PET showed heterogeneous expression of CAIX in all scans: overall, 9 of 17 (53%) metastatic target lesions expressed CAIX. Progressive disease occurred in 5/6 pts within 4 months on treatment, and progression occurred in all 8 of the CAIX non-avid lesions (100%) in these pts. One pt achieved a RECIST partial response (PR) with treatment – the pt for whom paired studies were obtained. For this pt, a PET PR was observed 2 cycles earlier than with conventional imaging. Conclusions: I-124 girentuximab PET/CT was safe and feasible in m ccRCC. We found that metastases were detected. More importantly, for pts with ccRCC refractory to conventional antiangiogenic therapies, CAIX expression was heterogeneous, and progression occurred in CAIX non-avid lesions. Taken together, these data suggest that CAIX expression identified with this functional imaging modality represents a biological prerequisite for continued antiangiogenic therapeutic activity, and the heterogeneous CAIX expression observed helps to explain why brivanib was not useful in this setting. Clinical trial information: NCT01253668.

A phase II study of vismodegib, a hedgehog (Hh) pathway inhibitor, combined with gemcitabine and nab-paclitaxel (nab-P) in patients (pts) with untreated metastatic pancreatic ductal adenocarcinoma (PDA)

257

Background: The Hh pathway is overexpressed in PDA tumors. Pre-clinically, Hh inhibitors have demonstrated a reduction in pancreatic cancer stem cells (pCSC) and stroma. Vismodegib, an oral small-molecule antagonist of the Hh pathway, has previously been safely combined with Gemcitabine chemotherapy. Methods: Pts with untreated, metastatic PDA were treated with Gemcitabine (1000 mg/m2) + nab-P (125 mg/m2) on days 1, 8 and 15 of 28 days cycle. Vismodegib (150mg PO daily) was started on the second cycle. All drugs were continued until disease progression or unacceptable toxicities. Primary endpoint was progression-free survival (PFS). Secondary endpoints were overall survival (OS), response rate (RR), and toxicity. Pre and post treatment tumor biopsies were obtained from primary or metastatic lesions. Results: 59 patients have been enrolled at 3 sites. Median age 60 (range 42-86); ECOG PS 0/1: 23 (40%)/ 34 (60%); male/female 32 (54%)/ 27 (46%). Estimated median PFS and OS in ITT population was 5.5 and 10 mo respectively (95% CI: 5.2-5.9 / 7.3-11). Of the 49 pts evaluable for response to date, 1 (2%) had CR, 20 (41%) had PR, 21 (43%) had SD and 7 (14%) had PD. Common Gr ≥3 toxicities: neutropenia 37.5% (n=21), anemia 21.4% (n=12), neuropathy 16.1% (n=9) and fatigue 9.4% (n=5). All patients with partial response had response within the primary pancreatic tumor. CA19-9 declines of >70% occurred in 57% of patients with measurable levels. Conclusions: Addition of Vismodegib to Gemcitabine/nab-P is well tolerated in patients with untreated PDA. This trial is ongoing to complete 80 patients. Blood and tumor tissue biomarker analyses for stem cells, Hh signaling and stromal activity are ongoing and will be reported in ASCO GI 2014. Clinical trial information: NCT01088815.

Adjuvant chemotherapy after trimodality therapy in locally advanced esophageal cancer

144

Background: The benefit of adjuvant chemotherapy after preoperative chemoradiation and surgery is unclear in patients with locally advanced esophageal cancer. We studied the toxicities and clinical outcomes in patients treated with or without adjuvant chemotherapy (CTX) after trimodality therapy. Methods: Records of patients with T3+ or N+ esophageal cancer who received preoperative chemoradiation followed by surgical resection from 2003-2013 were reviewed. Patients with postoperative deaths or poor performance status within 3 months after surgery were excluded (n = 13). Tolerability and hematologic toxicities of adjuvant CTX were recorded. Clinical outcomes of patients treated with adjuvant CTX were compared with a cohort of patients who received no further therapy (NFT). Results: Of the 81 trimodality patients included in the study, 53 received CTX and 28 received NFT after surgery. Median follow-up time was 23 months. FOLFOX (34%), cisplatin/5-FU (15%), 5-FU/LV (15%), ECF (13%), and carboplatin/paclitaxel (9%) were the most commonly used adjuvant regimens. Multiple rationales for adjuvant CTX were cited, including pathologic nodal status (32%), favorable pathologic response (61%), and provider preference (51%). Grade III/IV hematologic toxicity occurred in 11% of the CTX group: leukopenia (8%/2%), neutropenia (4%/4%), and thrombocytopenia (2%/0%). Two patients in the CTX group did not complete their prescribed CTX, which was discontinued after 1 cycle. Patient and clinical characteristics between CTX and NFT patients were well-balanced, except for pathologic complete response (pCR) rates (CTX 25% vs. NFT 50%, p=0.03). Three-year OS and DFS were similar between CTX and NFT patients (74% vs 70%, 60% vs. 64%, respectively). In patients who achieved pCR (33% overall), adjuvant CTX was associated with an improved 3-yr OS (86% vs. 62%), but the difference did not reach statistical significance (p=0.22). Distant failures occurred in 11% of the CTX group and 18% of the NFT group. Conclusions: Adjuvant CTX after trimodality therapy in esophageal cancer is feasible and well-tolerated with encouraging clinical outcomes. Further studies are needed to define the role of adjuvant CTX in these patients.

A phase II trial of gemcitabine, irinotecan and panitumumab in advanced cholangiocarcinoma

BACKGROUND

Current data suggest that chemotherapy combinations may be superior to single agents in biliary tract cancer. The epidermal growth factor receptor (EGFR) pathway appears to be associated with tumor stage, prognosis and response to therapy. This trial was designed to evaluate the tolerability and efficacy of the combination of panitumumab, a monoclonal anti-EGFR antibody, with gemcitabine and irinotecan.

PATIENTS AND METHODS

Patients with advanced (unresectable or metastatic) cholangiocarcinoma, ECOG PS 0-2, and adequate organ function were treated with panitumumab (9 mg/kg) on day 1, and gemcitabine (1000 mg/m(2)) and irinotecan (100 mg/m(2)) on days 1 and 8 of a 21-day cycle. The primary objective was to evaluate the 5-month progression-free survival (PFS). Secondary objectives included overall response rate (ORR) and overall survival (OS). Mutational analyses of EGFR, KRAS and BRAF were carried out when feasible.

RESULTS

Thirty-five patients received a median of 7 (0-30) cycles. The most common grade 3/4 toxic effects were neutropenia (10 patients, 29%), thrombocytopenia (10 patients, 29%), skin rash (13 patients, 37%) and dehydration (9 patients, 26%). Two patients had CR, 9 had partial response (PR), and 15 had SD for a disease-control rate of 74% (by RECIST) in 28 assessable patients. Two patients went on to have surgical resection. The 5-month PFS was 69%. The median PFS was 9.7 months and the median OS was 12.9 months. In 17 testable samples, no EGFR or BRAF mutations were identified; there were 7 KRAS mutations, with no difference in OS by KRAS status.

CONCLUSIONS

This study showed encouraging efficacy of this regimen with good tolerability. Further study in this area is warranted. Clinical Trials Number: The trial was registered with the National Cancer Institute (www.clinicaltrials.gov identifier NCT00948935).

Phase 1 and pharmacodynamic trial of everolimus in combination with cetuximab in patients with advanced cancer

BACKGROUND

Preclinical and clinical studies suggest mTOR (mammalian target of rapamycin) inhibitors may have metabolic and antiangiogenic effects, and synergize with epidermal growth factor pathway inhibitors. Therefore, a phase 1/pharmacodynamic trial of everolimus with cetuximab was performed.

METHODS

A total of 29 patients were randomized to a run-in of oral everolimus (30, 50, or 70 mg) or cetuximab (400 mg/m(2) loading, 250 mg/m(2) maintenance) weekly, followed by the combination in this dose-escalation study. Primary endpoints were phase 2 dose and toxicity characterization. [(18)F]Fluorodeoxyglucose positron emission tomography (FDG-PET) was performed as a pharmacodynamic marker of mTOR inhibition, and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was performed as an indicator of tumor perfusion changes, at 3 time points.

RESULTS

Everolimus and cetuximab were tolerable at full doses, with an expected toxicity profile. Dose-limiting toxicities in the everolimus 70 mg group included grade 3 skin toxicity in 2 patients, and mucositis in 1 patient. Of 16 patients evaluable for response, 5 had stable disease lasting 4 to 19 months. Mean change in maximum standardized uptake value (SUV(max)) for those treated initially with everolimus was -24% (2% to -54%), and with cetuximab was -5% (-23 to 36%). The K(trans) measured by DCE-MRI did not decrease, regardless of run-in drug.

CONCLUSIONS

Everolimus and cetuximab can be safely administered at standard doses, and are associated with prolonged disease control. The recommended phase 2 dose of oral weekly everolimus is 70 mg in combination with standard cetuximab. Imaging studies reveal that metabolic inhibition by everolimus alone and in combination with cetuximab predominates over changes in tumor perfusion in this patient population.

A phase I study of an agonist CD40 monoclonal antibody (CP-870,893) in combination with gemcitabine in patients with advanced pancreatic ductal adenocarcinoma

PURPOSE

This phase I study investigated the maximum-tolerated dose (MTD), safety, pharmacodynamics, immunologic correlatives, and antitumor activity of CP-870,893, an agonist CD40 antibody, when administered in combination with gemcitabine in patients with advanced pancreatic ductal adenocarcinoma (PDA).

EXPERIMENTAL DESIGN

Twenty-two patients with chemotherapy-naïve advanced PDA were treated with 1,000 mg/m(2) gemcitabine once weekly for three weeks with infusion of CP-870,893 at 0.1 or 0.2 mg/kg on day three of each 28-day cycle.

RESULTS

CP-870,893 was well-tolerated; one dose-limiting toxicity (grade 4, cerebrovascular accident) occurred at the 0.2 mg/kg dose level, which was estimated as the MTD. The most common adverse event was cytokine release syndrome (grade 1 to 2). CP-870,893 infusion triggered immune activation marked by an increase in inflammatory cytokines, an increase in B-cell expression of costimulatory molecules, and a transient depletion of B cells. Four patients achieved a partial response (PR). 2-[(18)F]fluoro-2-deoxy-d-glucose-positron emission tomography/computed tomography (FDG-PET/CT) showed more than 25% decrease in FDG uptake within primary pancreatic lesions in six of eight patients; however, responses observed in metastatic lesions were heterogeneous, with some lesions responding with complete loss of FDG uptake, whereas other lesions in the same patient failed to respond. Improved overall survival correlated with a decrease in FDG uptake in hepatic lesions (R = -0.929; P = 0.007).

CONCLUSIONS

CP-870,893 in combination with gemcitabine was well-tolerated and associated with antitumor activity in patients with PDA. Changes in FDG uptake detected on PET/CT imaging provide insight into therapeutic benefit. Phase II studies are warranted.

Increase in blood pressure with sorafenib exposure: Renal cell carcinoma (RCC) versus other solid tumors

e15564

Background: Tyrosine kinase inhibitors (TKIs) such as sorafenib are widely used in the treatment of solid tumor malignancies. Incident hypertension with angiogenesis inhibitors has been well-documented in the RCC where incident hypertension on treatment is associated with improved clinical outcome. Little has been reported about increases in (BP) with TKIs in other solid tumor malignancies. Methods: We performed a retrospective cohort study examining changes in BP with sorafenib among the 101 patients treated at the University of Pennsylvania on a randomized discontinuation trial examining sorafenib in patients with advanced solid tumor malignancies. Solid tumor diagnoses were established on the basis of tumor histology. Treatment of patients on study with sorafenib was initiated at 400 mg BID. Patients were treated for at least 12 weeks and were evaluated at least every three weeks in the clinic. BP was recorded at each visit. Sorafenib exposure was recorded by patients in a pill diary. The primary endpoint for this study was a maximal change in BP defined as the difference between baseline BP and highest subsequent recorded systolic and diastolic BPs on treatment. Results: 72% of RCC patients developed an increase in systolic BP (SBP) of at least 20 mmHg as compared to 32% of non-RCC patients. The mean increase in SBP on study for RCC patients was 30 mmHg versus 19 mmHg in non-mRCC patients. RCC patients in the top quartile of increased SBP showed a mean increase of 54 mmHg as compared to 35 mmHg for non-mRCC patients. A chi-squared test of proportions and t-tests were used to compare rates and means, respectively. Each of the aforementioned differences were found to be statistically significant with p-values <0.003. These relationships also held true for diastolic BP. There was no difference in SBP between groups in terms of age or sorafenib exposure. Differences in BP were not related to differences in glomerular filtration rate. Conclusions: In these sorafenib-treated patients, the proportion of patients with increased BP and the mean amplitude of change in BP both were significantly greater in the RCC population than in the non-RCC group.

Phase I study of the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of the oral inhibitor of indoleamine 2,3-dioxygenase (IDO1) INCB024360 in patients (pts) with advanced malignancies

3025

Background: INCB024360 is a potent, selective inhibitor of IDO1. As the catabolism of tryptophan (Trp) to kynurenine (Kyn) by IDO1 inhibits immune responses and IDO1 expression is elevated in many human cancers, IDO1 inhibition may potentiate effective antitumor immune responses. Methods: This dose-escalation study in adult pts with advanced malignancies used a 3+3 design to determine MTD, toxicity, PK, PD, and tumor response rate. Daily doses of INCB024360 were evaluated in 28-day cycles in 8 cohorts (50 mg once daily; 50 mg, 100 mg, 300 mg, 400 mg, 500 mg, 600 mg, or 700 mg BID). Treatment continued until disease progression or unacceptable toxicity. PK and PD samples were drawn on days 1 and 15. Results: 52 pts have been treated. Tumor types included colorectal (56%), melanoma (12%), and other (33%). The most common adverse events (≥20%) were fatigue, nausea, decreased appetite, vomiting, constipation, abdominal pain, diarrhea, dyspnea, back pain, and cough. The most common grade 3 or 4 adverse events were abdominal pain, hypokalemia, and fatigue (9.6% each). One DLT each was observed at 300 mg BID (grade 3 radiation pneumonitis) and 400 mg BID (grade 3 fatigue); no DLTs were observed in the 18 pts treated with 600 mg or 700 mg BID. There were no objective responses. At 56 days, stable disease was seen in 15 patients and lasted ≥112 days in 7 patients. Significant dose-dependent reductions in plasma Kyn/Trp ratios and Kyn levels were detected at all doses and in all pts. Maximal effects were observed at doses ≥300 mg BID. With repeat dosing, 700 mg BID provided an average plasma concentration ~5-fold the projected IC90. Overall, doses ≥300 mg BID achieved greater than 90% inhibition of IDO1 throughout the dosing period. Conclusions: INCB024360 was generally well tolerated at doses of up to 700 mg BID and there appears to be no correlation of dose with toxicity. Doses ≥300 mg BID were capable of >90% inhibition of IDO1 activity and found to effectively normalize plasma Kyn levels. The recommended dose as monotherapy is 600 mg BID. Clinical trial information: NCT01195311.

A phase II trial of an oral CDK 4/6 inhibitor, PD0332991, in advanced breast cancer

519

Background: The G1/S checkpoint of the cell cycle is frequently dysregulated in breast cancer (BC). Initial efficacy of PD0332991, a potent oral inhibitor of cyclin-dependent kinases (CDKs) 4/6 was shown in a variety of solid tumors and in combination with letrozole in a randomized phase II trial. Methods: We performed a phase II, single arm trial of PD0332991 in women with advanced BC. The primary objectives were safety and efficacy. Eligible patients had histologically-confirmed, stage IV BC with primary or metastatic tumor positive for retinoblastoma (Rb) protein expression, measureable disease by RECIST and adequate organ function/performance status. PD0332991 was given at 125 mg orally, days 1 – 21 of a 28-day cycle. Tumor was assessed every 2 cycles. A two-stage statistical design was employed. Secondary objectives included predictive biomarker assessment. Results: 36 patients were enrolled; 28 who completed cycle 1 are reported: 18 (64%) HR+/Her2-, 2 (7%) HR+/Her2+ and 8 (29%) HR-/Her2-. 90% had prior chemotherapy for metastatic disease (median 3 lines); 78% had prior hormonal therapy (median 2 lines). Grade 3/4 toxicities were limited to transient neutropenia (50%) and thrombocytopenia (21%). One episode of neutropenic sepsis occurred in cycle 1 in patient with 6 prior chemo regimens. All other toxicities were grade 1/2. Treatment was interrupted in 7 (25%) and dose reduced in 13 (46%) pts for cytopenias. For response data see table. Responses occurred at dose levels as low as 50 mg. Median PFS (months, 95% CI) was 4.1 (2.3,7.7) for ER+/Her2-, 18.8 (5.1,∞) for ER+/Her+ and 1.8 (0.9,∞) for ER-/Her2-. 27/28 patients discontinued study for progressive disease (PD); 1 due to patient preference. Conclusions: Therapy with PD0332991 alone is well-tolerated and demonstrates response or prolonged stable disease (SD) in patients with BC despite prior hormonal and chemotherapy. Expansion within subtypes and molecular predictors of response are being investigated. Clinical trial information: NCT01037790. [Table: see text]

Microarray gene expression study of the RESPECT trial for the identification of prognostic and predictive markers

e14561

Background: The RESPECT trial (n = 198) tested the addition of Sorafenib to standard mFOLFOX6 treatment in first line metastatic colorectal cancer (mCRC) patients but resulted in no statistical significant improvement in progression free survival, and no evidence for overall benefit. Sorafenib inhibits several Raf kinases (including B-Raf). Samples with high BRAF-mutant-like score were previously shown to identify a subset of colon tumors with a similar biology and outcome to BRAF mutant patients (Popovici et al. J. Clin. Oncol., 30(12):1288–95, 2012). Methods: A subset of 125 patients from the trial was available for gene expression analysis from their primary tumor FFPE samples, using the Colon DSA gene expression arrays from Almac. Mutation status for KRAS and BRAF was previously assessed. The potential prognostic and/or predictive effect of a high BRAF-mutant-like score was assessed. The analyses were performed using Cox proportional hazards regression models and Kaplan-Meier curves. The logrank test was used to compare the survival distributions (significance level: 5%). Results: Molecular profiling was performed on FFPE tissue samples from primary tumors of 125 mCRC patients, 95 samples (47 in the combined arm; 3 BRAF mutants) were successfully processed. Limitations in amount of material available in this retrospective analysis led to failure to reach the required RNA amount for amplification in 30 samples (dropout rate = 24%). The collected gene expression data was of good quality: all 95 array profiles could be used (10 were flagged for slightly inferior quality). The BRAF-mutant-like score was recognized as marker of poor OS in a Cox regression model (HR = 1.55 [95% CI: 1.12 - 2.13], 1 unit = 1 IQR, P = 0.007). The HR difference between the two arms (combined arm: HR = 1.36; reference arm: HR = 1.41) is not significant. Conclusions: The poor survival of metastatic colorectal cancer patients with a BRAF-mutated-like tumor is confirmed, but no predictive effect was found. FFPE tissues are well-suited for this kind of study and allow to accurately test the hypotheses of interest. Further analyses are planned to generate hypotheses about markers of sensitivity to mFOLFOX6 or Sorafenib.

Intergroup randomized phase III study of postoperative irinotecan, 5-fluorouracil, and leucovorin versus oxaliplatin, 5-fluorouracil, and leucovorin versus 5-fluorouracil and leucovorin for patients with stage II or III rectal cancer receiving either preoperative radiation and 5-fluorouracil or postoperative radiation and 5-fluorouracil: ECOG E3201—An updated survival analysis

e14711

Background: Postoperative adjuvant chemotherapy has been historically limited to single agent 5FU in stage II/III rectal cancer pts. This phase III trial evaluated differences between pts treated with adjuvant FOLFOX versus FOLFIRI versus FU alone in stage II/III rectal cancer. Methods: Eligibility: resectable (T3-4 N0,Tany N1-3) adenocarcinoma rectum ≤12cm from anal verge. Pts had the option to receive FU with pre or postoperative XRT (50.4Gy). Preoperative FU/XRT pts were randomized to adjuvant FOLFIRI (arm A), FOLFOX (arm B), FU/LV(arm C). Postoperative FU/XRT pts were randomized to adjuvant FOLFIRI (arm D), FOLFOX (arm E), FU/LV (arm F). Pts received 8 cycles. Overall survival (OS) was the primary endpoint. Secondary endpoints included toxicity, sphincter preservation and patterns of failure. Results: 225pts out of planned 3150 were enrolled (10/03 to 10/05). Data Monitoring Committee closed E3201 when the GI Intergroup developed an alternative trial with bevacizumab (E5204). 179 pts were randomized; (A:28, B:25, C:30, D:31, E:33, F:32). There was increased grade 3/4 toxicity, mainly diarrhea,in postoperative FU/XRT arms (D:39%), (E:28%), (F:48%). Twenty-two (12%) pts did not receive adjuvant therapy. At a median follow up of 7.4yrs, the five-year recurrence free rate was 69%. Median OS was 8.3 yrs. There was no statistical difference in OS between all randomized groups. Five-year OS in arms (A:B:C:D:E:F) were (73%, 83%, 83%, 73%, 78%, 73%) respectively. Conclusions: FOLFOX can be safely administered to rectal cancer pts following chemo radiation. Given limitations of early trial closure and small sample size, there was no difference in OS between pts who received FU alone, oxaliplatin based or irinotecan based adjuvant therapy. Clinical trial information: NCT00068692.

Sorafenib in combination with oxaliplatin, leucovorin, and fluorouracil (modified FOLFOX6) as first-line treatment of metastatic colorectal cancer: the RESPECT trial

PURPOSE

This randomized, double-blind, placebo-controlled, phase IIb study evaluated adding sorafenib to first-line modified FOLFOX6 (mFOLFOX6) for metastatic colorectal cancer (mCRC).

EXPERIMENTAL DESIGN

Patients were randomized to sorafenib (400 mg b.i.d.) or placebo, combined with mFOLFOX6 (oxaliplatin 85 mg/m(2); levo-leucovorin 200 mg/m(2); fluorouracil 400 mg/m(2) bolus and 2400 mg/m(2) continuous infusion) every 14 days. Primary endpoint was progression-free survival (PFS). Target sample was 120 events in 180 patients for >85% power (two-sided α = 0.20) to detect an HR = 0.65.

RESULTS

Of 198 patients randomized, median PFS for sorafenib plus mFOLFOX6 was 9.1 months versus 8.7 months for placebo plus mFOLFOX6 (HR = 0.88; 95% CI, 0.64-1.23; P = 0.46). There was no difference between treatment arms for overall survival. Subgroup analyses of PFS and overall survival showed no difference between treatment arms by KRAS or BRAF status (mutant and wild type). The most common grade 3/4 adverse events in the sorafenib and placebo arms were neutropenia (48% vs. 22%), peripheral neuropathy (16% vs. 21%), and grade 3 hand-foot skin reaction (20% vs. 0%). Treatment discontinuation because of adverse events was 9% and 6%, respectively. Generally, dose intensity (duration and cumulative doses) was lower in the sorafenib arm than in the placebo arm.

CONCLUSION

This study did not detect a PFS benefit with the addition of sorafenib to first-line mFOLFOX6 for mCRC. KRAS and BRAF status did not seem to impact treatment outcomes but the subgroups were small. These results do not support further development of sorafenib in combination with mFOLFOX6 in molecularly unselected patients with mCRC.

Autophagy inhibition sensitizes colon cancer cells to antiangiogenic and cytotoxic therapy

PURPOSE

Autophagy is a critical survival pathway for cancer cells under conditions of nutrient or oxygen limitation, or cell stress. As a consequence of antiangiogenic therapy, solid tumors encounter hypoxia induction and imbalances in nutrient supply. We wished to determine the role of autophagy in protection of tumor cells from the effects of antiangiogenic therapy and chemotherapy. We examined the effect of inhibiting autophagy on hypoxic colon cancer cells in vitro and on bevacizumab- and oxaliplatin-treated mouse xenografts in vivo.

EXPERIMENTAL DESIGN

The autophagic response to hypoxia and DNA-damaging agents was assessed by fluorescent microscopic imaging, autophagy-related gene expression, and by electron microscopic ultrastructural analysis. Pharmacologic and molecular approaches to autophagy inhibition were taken in a panel of colon cancer cell lines. Mouse xenograft models were treated with combinations of oxaliplatin, bevacizumab, and chloroquine to assess effects on tumor growth reduction and on pharmacodynamic markers of autophagy inhibition.

RESULTS

Autophagy was induced in colon cancer models by exposure to both hypoxia and oxaliplatin. Inhibition of autophagy, either with chloroquine or by downregulation of beclin1 or of ATG5, enhanced sensitivity to oxaliplatin under normal and hypoxic conditions in a synergistic manner. Both bevacizumab and oxaliplatin treatments activate autophagy in HT29 murine xenografts. The addition of chloroquine to bevacizumab-based treatment provided greater tumor control in concert with evidence of autophagy inhibition.

CONCLUSIONS

These findings implicate autophagy as a mechanism of resistance to antiangiogenic therapies and support investigation of inhibitory approaches in the management of this disease.

Increase in blood pressure with sorafenib exposure in renal cell carcinoma versus other solid tumors

384

Background: Tyrosine kinase inhibitors (TKIs) such as sorafenib are widely used in the treatment of solid tumor malignancies. Incident hypertension with angiogenesis inhibitors has been well-documented in the population of patients with renal cell carcinoma (RCC) where incident hypertension on treatment is associated with improved clinical outcome. Little has been reported about increases in blood pressure with TKIs in other solid tumor malignancies. Methods: We performed a retrospective cohort study examining changes in blood pressure with sorafenib among the 101 patients treated at the University of Pennsylvania on a randomized discontinuation trial examining sorafenib in patients with advanced solid tumor malignancies. Solid tumor diagnoses were established on the basis of tumor histology. Treatment of patients on study with sorafenib was initiated at 400 mg BID. Patients were treated for at least 12 weeks and were evaluated at least every three weeks in the clinic. Blood pressure was recorded at each visit. Sorafenib exposure was recorded by patients in a pill diary. The primary endpoint for this study was a maximal change in blood pressure defined as the difference between baseline blood pressure and highest subsequent recorded systolic and diastolic blood pressures on treatment. Results: 72% of RCC patients developed an increase in systolic blood pressure (SBP) of at least 20 mmHg as compared to 32% of non-RCC patients. The mean increase in SBP on study for RCC patients was 30 mmHg versus 19 mmHg in non-mRCC patients. RCC patients in the top quartile of increased SBP showed a mean increase of 54 mmHg as compared to 35 mmHg for non-mRCC patients. A chi-squared test of proportions and t-tests were used to compare rates and means, respectively. Each of the aforementioned differences were found to be statistically significant with p-values <0.003. These relationships also held true for diastolic blood pressure. There was no difference in SBP between groups in terms of age or sorafenib exposure. Conclusions: In these patients treated with sorafenib the proportion of patients with increased blood pressure and the mean amplitude of change in blood pressure both were significantly greater in the RCC population than in the non-RCC group.

FG-3019, a human monoclonal antibody to CTGF, with gemcitabine/erlotinib in patients with locally advanced or metastatic pancreatic ductal adenocarcinoma

213

Background: Connective tissue growth factor (CTGF) is overexpressed in PDAC and facilitates local desmoplasia, tumor survival and metastasis. FG-3019 is a CTGF-specific monoclonal antibody that decreases tumor growth and metastases and prolongs survival in orthotopic and KPC mouse models. This study evaluates safety and efficacy of FG-3019 with gemcitabine/erlotinib in patients with PDAC. Methods: In a nongoing open-label, dose-escalation study, FG-3019 was used in combination with gemcitabine and erlotinib in patients with previously untreated, measurable, locally advanced or metastatic PDAC. Cohorts 1−6 received FG-3019 Q2W at 3, 10, 15, 25, 35 or 45 mg/kg. Cohort 7 received 35 mg/kg on Day 1 and then 17.5 mg/kg QW. Cohort 8 received 45 mg/kg on Day 1 and then 22.5 mg/kg QW. Results: 75 patients were enrolled at 7 centers. Baseline data: Stage III= 15, Stage IV=60; ECOG=0 (n=32), ECOG=1 (N=43). No SAEs or DLTs related to FG-3019 occurred at any dose. In per protocol population (n=68) median PFS and OS were 4.3 and 9.4 months respectively. Baseline plasma CTGF levels correlated inversely with PFS and OS (p=0.0029) (ITT population). Median FG-3019 Cmax and Cmin increased linearly with dose. Because of considerable overlap between subjects across cohorts, outcomes are correlated with drug exposure. OS, but not PFS, correlated with exposure after the first FG-3019 dose (Day 1 Cmax, p=0.009; Day 15 Cmin, p=0.005; ITT population). 47% of evaluable subjects had >50% decrease in CA19.9.The magnitude of reduction correlated with Day 1 Cmax (p=0.04) and inversely with baseline plasma CTGF (p=0.01). As FG-3019 accumulated over time, minimum FG-3019 exposure (Cmin) of 150 ug/mL on Day 43 appeared to be a threshold. Median OS was 7.7 and >8.6 months for subjects < (n=15) or ≥ (n=43) 150 ug/mL respectively on Day 43 (p=0.0034). Day 43 Cmin < 150, none alive at 12 months: Day 43 Cmin >150, 8 alive at 12 months, 17 alive 6.7-12 months. Conclusions: FG-3019 combined with gemcitabine/erlotonib is well tolerated. Interim results in this open-label study suggest OS improves with increasing exposure to FG-3019. Clinical trial information: NCT01181245.

Association between VEGF splice isoforms and progression-free survival in metastatic colorectal cancer patients treated with bevacizumab

PURPOSE

Bevacizumab improves survival for patients with metastatic colorectal cancer with chemotherapy, but no proven predictive markers exist. The VEGF-A splice form, VEGF(165)b, anti-angiogenic in animal models, binds bevacizumab. We tested the hypothesis that prolonged progression-free survival (PFS) would occur only in patients with low relative VEGF(165)b levels treated with bevacizumab.

EXPERIMENTAL DESIGN

Blinded tumor samples from the phase III trial of FOLFOX4 ± bevacizumab were assessed for VEGF(165)b and VEGF(total) by immunohistochemistry and scored relative to normal tissue. A predictive index (PI) was derived from the ratio of VEGF(165)b:VEGF(total) for 44 samples from patients treated with FOLFOX + bevacizumab (arm A) and 53 samples from patients treated with FOLFOX4 (arm B), and PFS, and overall survival (OS) analyzed on the basis of PI relative to median ratio.

RESULTS

Unadjusted analysis of PFS showed significantly better outcome for individuals with VEGF(165)b:VEGF(total) ratio scores below median treated with FOLFOX4 + bevacizumab compared with FOLFOX4 alone (median, 8.0 vs. 5.2 months; P < 0.02), but no effect of bevacizumab on PFS in patients with VEGF(165)b:VEGF(total) ratio >median (5.9 vs. 6.3 months). These findings held after adjustment for other clinical and demographic features. OS was increased in arm A (median, 13.6 months) compared with arm B (10.6 months) in the low VEGF(165)b group, but this did not reach statistical significance. There was no difference in the high VEGF(165)b:VEGF(total) group between FOLFOX + bevacizumab (10.8 months) and FOLFOX alone (11.3 months).

CONCLUSION

Low VEGF(165)b:VEGF(total) ratio may be a predictive marker for bevacizumab in metastatic colorectal cancer, and individuals with high relative levels may not benefit.

Activity of the oral MEK inhibitor trametinib in patients with advanced melanoma: a phase 1 dose-escalation trial

BACKGROUND

MEK is a member of the MAPK signalling cascade that is commonly activated in melanoma. Direct inhibition of MEK blocks cell proliferation and induces apoptosis. We aimed to analyse safety, efficacy, and genotyping data for the oral, small-molecule MEK inhibitor trametinib in patients with melanoma.

METHODS

We undertook a multicentre, phase 1 three-part study (dose escalation, cohort expansion, and pharmacodynamic assessment). The main results of this study are reported elsewhere; here we present data relating to patients with melanoma. We obtained tumour samples to assess BRAF mutational status, and available tissues underwent exploratory genotyping analysis. Disease response was measured by Response Evaluation Criteria in Solid Tumors, and adverse events were defined by common toxicity criteria. This study is registered with ClinicalTrials.gov, number NCT00687622.

FINDINGS

97 patients with melanoma were enrolled, including 81 with cutaneous or unknown primary melanoma (36 BRAF mutant, 39 BRAF wild-type, six BRAF status unknown), and 16 with uveal melanoma. The most common treatment-related adverse events were rash or dermatitis acneiform (n=80; 82%) and diarrhoea (44; 45%), most of which were grade 2 or lower. No cutaneous squamous-cell carcinomas were recorded. Of 36 patients with BRAF mutations, 30 had not received a BRAF inhibitor before; two complete responses (both confirmed) and ten partial responses (eight confirmed) were noted in this subgroup (confirmed response rate, 33%). Median progression-free survival of this subgroup was 5·7 months (95% CI 4·0-7·4). Of the six patients who had received previous BRAF inhibition, one unconfirmed partial response was recorded. Of 39 patients with BRAF wild-type melanoma, four partial responses were confirmed (confirmed response rate, 10%).

INTERPRETATION

Our data show substantial clinical activity of trametinib in melanoma and suggest that MEK is a valid therapeutic target. Differences in response rates according to mutations indicate the importance of mutational analyses in the future.

FUNDING

GlaxoSmithKline.

MGCD265, a multitargeted oral tyrosine kinase receptor inhibitor of Met and VEGFR, in combination with erlotinib in patients with advanced solid tumors

e13602

Background: MGCD265 is a multi-target oral tyrosine kinase receptor inhibitor that targets Met (wild type and clinically-relevant Met mutants), VEGFRs 1, 2, 3, Tie and Ron. Combining Met and EGFR inhibitors has been shown to be synergistic and can overcome resistance to EGFR inhibitors. MGCD265 in combination with erlotinib is being evaluated clinically for safety and efficacy. Methods: This is a phase I dose escalation trial of patients (pts) with advanced solid tumors, using the classic 3+3 design. MGCD265 and erlotinib were administered every day over a 21-day cycle. Safety evaluation included determination of dose limiting toxicities (DLTs) and the maximum tolerated dose of the combination. The pharmacokinetic (PK), pharmacodynamic (PD) profiles as well as anti-tumor activity, using RECIST 1.1, were also evaluated. Results: As ofJanuary 11, 2012, 45 pts were enrolled (median age: 58 years old; M/F: 27/18; ECOG 0/1: 20/25). MGCD265 was dose escalated from 96 mg/m2 QD to 162 mg/m2 BID, in combination with erlotinib (initially at 100 mg then at 150 mg QD). Diarrhea (n=6) was the only treatment-related ≥ grade 3 adverse event observed in ≥ 2 pts. The observed DLTs (all grade 3) were (n=1): diarrhea (96 mg/m2 QD MGCD265+100 mg erlotinib), rash and fatigue (144 mg/m2 QD MGCD265+150 mg erlotinib) and rhabdomyolysis (162 mg/m2 BID MGCD265+150 mg erlotinib). One out of 3 pts with NSCLC, who was positive for activating EGFR mutation, experienced a partial response (duration of response of 8 cycles). Seven pts with a variety of tumors experienced stable disease for 6 cycles or more. Three out of 8 pts with gastroesophageal cancer remained on study for ~12-26 cycles. The PD profile indicated a decrease in the plasma level of HGF at Cycle 1 Day 8 compared to baseline in some patients. Conclusions: MGCD265, at the doses tested, was well tolerated in combination with full-dose erlotinib. The activity of MGCD265 combined with erlotinib supports phase II development of the combination.

A phase II trial of gemcitabine, irinotecan, and panitumumab in advanced cholangiocarcinoma, with correlative analysis of EGFR, KRAS, and BRAF: An interim report

4111

Background: Cholangiocarcinoma is an aggressive neoplasm. Current chemotherapy approaches achieve modest results. The epidermal growth factor receptor (EGFR) pathway appears to be associated with tumor stage, prognosis and response to therapy. This trial was designed to evaluate the tolerability and efficacy of the combination of panitumumab, a monoclonal anti-EGFR antibody, with gemcitabine and irinotecan, in patients with advanced cholangiocarcinoma. Molecular analysis of EGFR pathway genes was planned as well. Methods: Patients with advanced (unresectable or metastatic) cholangiocarcinoma, ECOG PS 0-2, and adequate liver, kidney and bone marrow function were treated with panitumumab (9 mg/kg) on day 1, and gemcitabine (1000 mg/m2) and irinotecan (100 mg/m2) on days 1 and 8 of a 21-day cycle. Tissue specimens were collected at diagnosis for correlative molecular analyses. Primary objective is to evaluate the 5-month progression-free survival (PFS) rate. Secondary objectives include overall response rate (ORR), overall survival (OS) and toxicity of the combination. Mutational analysis of EGFR (del 19; 858), KRAS (codons 12, 13) and BRAF (V600E) was done on samples with adequate material for testing. Results: There have been 26 (of planned 42) patients recruited to the study. A median of 6 (0-30) cycles were administered. There were no treatment related deaths. The most common gr 3 or higher toxicities were neutropenia (10 pts, 38%), thrombocytopenia (10 pts, 38%), skin rash (10 pts, 38%) and diarrhea (3 pts, 12%). During the study, there were 3 CR, 6 PR, 10 SD (disease control rate of 90%), and 2 PD (by RECIST) in 21 evaluable pts. Two pts went on to have surgical resection. Median OS is 12.7 months. Of 13 testable samples, no EGFR or BRAF mutations were identified; however, there were 7 KRAS mutations. Retrospective analysis showed no difference in OS by KRAS mutation status. Conclusions: Interim evaluation of this ongoing study showed encouraging tolerability and efficacy of this regimen. Several patients have KRAS mutations; there appears to be no association with response, however. The pre-specified efficacy criteria to continue enrollment were met.

MGCD265, a multitargeted oral tyrosine kinase receptor inhibitor of Met and VEGFR, in combination with docetaxel

e13604

Background: MGCD265 is a multi-target oral tyrosine kinase receptor inhibitor that targets Met, VEGFRs 1, 2, 3, Tie and Ron. The maximum tolerated dose (MTD) of MGCD265 in combination with docetaxel was initially determined using micronized tablets. MGCD265 formulation was improved and the MTD of MGCD265 in combination with docetaxel using the updated formulation was re-evaluated. Methods: Patients (pts) with metastatic or advanced solid tumors were enrolled in this Phase I, open-label, dose-escalating study to assess safety, pharmacodynamics (PD) and pharmacokinetics (PK) as well as anti-tumor activity of the combination. MGCD265 was administered every day over a 3-week cycle and docetaxel (50 then 75 mg/m2) was given intravenously once every 3 weeks (q3w). Results: As of January 11, 2012, 34 pts were enrolled (M/F: 19/15; ECOG 0/1: 19/15; median age: 64 years old). The MTD of the combination was initially defined as MGCD265 (72 mg/m2 BID)+docetaxel (75 mg/m2 q3w) based on the occurrence of dose limiting toxicities (DLTs) in 2 pts who were treated with MGCD265 at 96 mg/m2 BID (fatigue in 1 pt and diarrhea & lipase elevation in the other pt). The updated formulation of MGCD265 was introduced at 48 mg/m2 BID (n=3) with dose escalation to 72 mg/m2 BID (n=3) and 96 mg/m2 (n=4) with no observed DLTs, though the exposure of the two formulations were generally comparable. Overall, objective partial responses (per RECIST 1.1) were observed in 2/9 pts with NSCLC, 1/3 pts with prostate cancer and 1/1 pt with endometrial cancer. Stable disease for 6 cycles or more was observed in 6 pts. Treatment-related ≥ grade 3 toxicity reported in ≥ 2 pts were neutropenia, leukopenia, diarrhea and elevated lipase. The PD profile indicated an increase in the plasma level of VEGF and a decrease in plasma level of HGF at Cycle 1 Day 8 compared to baseline in some patients. Conclusions: MGCD265 was found to be well tolerated using the updated formulation in combination with full-dose docetaxel. Anti-cancer activity, supporting Phase II development of the combination, was observed.

Interim results of phase II trial of the cyclin-dependent kinase 4/6 inhibitor PD-0332991 in refractory retinoblastoma protein positive germ cell tumors

4596

Background: Deregulation of the retinoblastoma pathway in germ cell tumors (GCT) has been well documented. We previously reported that PD-0332991, a selective oral inhibitor of cyclin-dependent kinase 4/6, led to prolonged disease control in 3 patients (pts) with unresectable growing teratoma syndrome (NEJM, 2009). For these reasons, we initiated a phase II trial of PD-0332991 in pts with refractory retinoblastoma protein (Rb) positive (+) GCT. Methods: Pts with incurable refractory GCT that expressed Rb by immunohistochemistry were treated with PD-0332991 125 mg orally daily for 21 days followed by a 7 day break (cycle = 28 days). Tumor assessments were performed every 2 cycles. The primary endpoint was 6-month progression-free survival (PFS) rate. Results: As of 1/12/2012, archived tumors from 36 pts with refractory GCT were stained for Rb and 35 had ≥ 1+ staining. 18 of planned 24 pts have been enrolled and treated. Pt characteristics: 17 male, 1 female; median age, 31 years (range, 17-56); median ECOG performance status, 1 (range, 0-1); median number of prior chemotherapy regimens, 2 (range, 1-6); median number prior surgeries, 3 (range, 1-6). Pt pathology: mature teratoma (MT), 7; teratoma with malignant transformation (TMT), 7; mixed GCT, 2; late relapse (LR), 2. 16 pts are evaluable; 2 pts are too early to evaluate. 5 of 16 evaluable pts achieved 6-month PFS (3 MT, 1 TMT, 1 LR). Median PFS was 2 months (range, 0-17). No objective radiological responses were observed; 7 patients had best response of stable disease by RECIST criteria (3 MT, 3 TMT, 1 LR). Grade 3 toxicity included neutropenia (4 pts), thrombocytopenia (3 pts), anemia (1 pt), mucositis (1 pt). No grade 4 toxicity was seen. Analysis of archival tumor for predictive biomarkers including Rb and p16 expression is being performed. Conclusions: PD-0332991 has resulted in 6-month PFS in pts with refractory Rb + GCT, including pts with incurable teratomas.

Dasatinib combined with gemcitabine (Gem) in patients (pts) with locally advanced pancreatic adenocarcinoma (PaCa): Design of CA180-375, a placebo-controlled, randomized, double-blind phase II trial

TPS4134

Background: Dasatinib, a potent oral BCR-ABL and SRC family kinase (SFK) inhibitor, is approved for first- and second-line therapy of Philadelphia chromosome-positive chronic phase chronic myeloid leukemia (CML) in pts with newly diagnosed CML or CML resistant/intolerant to prior therapy. SRC expression and activity is upregulated in PaCa and correlates with reduced survival in resected high-grade PaCa (Morton, Gastroenterology 2010) and resistance to Gem, a PaCa standard of care (Duxbury, J Am Coll Surg 2004). In preclinical PaCa studies, inhibition of SFKs with dasatinib reduces tumor cell proliferation, migration, and invasion; increases apoptosis; sensitizes cells to Gem; and inhibits development of metastases in vivo either alone or in combination with Gem (Duxbury, Clin Cancer Res 2004; Duxbury, J Am Coll Surg 2004; Nagaraj, Mol Cancer Ther 2010; Morton, op cit). Phase I clinical studies of dasatinib and Gem therapy in PaCa have demonstrated feasibility and suggested efficacy of the combination (Uronis, ASCO 2009, abstract e15506). Methods: This double-blind phase II study tests whether addition of dasatinib to Gem is tolerable and improves efficacy in pts with histologically/cytologically confirmed unresectable locally advanced nonmetastatic PaCa. Eligible pts, aged ≥18 years with Eastern Cooperative Oncology Group performance status ≤1 and adequate organ function, are randomized 1:1 to Gem 1000 mg/m2 IV once weekly (Weeks 1–3 of a 4-week cycle) plus either dasatinib 100 mg once daily or matched placebo. Pts are treated until progression, unacceptable toxicity, withdrawal of consent, or study termination. The primary endpoint is OS, and secondary endpoints are progression-free survival and safety. Exploratory endpoints include freedom from distant metastases, measures of pain and fatigue, overall response rate, and carbohydrate antigen 19-9. Final study analysis will be conducted after 135 deaths; all pts will be followed for survival. To date, 23/200 pts have enrolled; estimated primary completion date is March 2013. ClinicalTrials.gov identifier: NCT01395017.

Pharmacodynamic assessment of INCB024360, an inhibitor of indoleamine 2,3-dioxygenase 1 (IDO1), in advanced cancer patients

2500^

Background: The ineffectiveness of the immune system to control tumor growth is, in part, a result of immunosuppression imposed by negative regulatory mechanisms. Indoleamine 2,3-dioxygenase 1 (IDO1), an enzyme that catabolizes the first and rate-limiting step in the degradation of the essential amino acid tryptophan (Trp) to kynurenine (Kyn), has been shown preclinically to play an important role in tumor-mediated immunosuppression. In cancer patients (pts), elevated IDO1 levels are associated with poor prognosis and shortened survival in a number of tumor types. Here we describe the pharmacodynamic (PD) assessment of INCB024360, a novel inhibitor of IDO1. Methods: Plasma samples were obtained from consented pts in study INCB 24360-101, a phase I dose-escalation study in patients with advanced malignancies. Trp and Kyn levels in plasma were determined by LC/MS/MS. IDO1 activity in activated peripheral blood cells was also monitored. Results: Using anti-IDO1 specific antisera and archived tumor samples, we found IDO1 expression in various human tumors, including ovarian, colorectal, breast and prostate. Consistent with this result, higher Kyn/Trp ratios (1.5-3.4 fold above healthy volunteers) were detected in archived plasma samples from pts, indicative of higher IDO1 activity in cancer pts. To date, 23 pts have been treated with the selective IDO1 inhibitor INCB024360. When plasma samples from patients were collected pre- and post-INCB024360 treatment, significant dose-dependent reductions in plasma Kyn/Trp ratios and Kyn levels were detected. As an additional biomarker measurement, whole blood samples collected from pts at various times after dosing were stimulated ex vivo with interferon-γ and lipopolysaccharide to increase IDO1 activity and also showed dose-dependent decreases in IDO activity. With the current dose regimens and assays we have successfully achieved sustained inhibition of >90% at a well tolerated dose of INCB024360. Conclusions: This is the first demonstration of PD activity of an IDO1-specific inhibitor in cancer pts. Our study also confirms that IDO1 is frequently activated in cancer pts. The methods described will be used to establish a phase II dose.

Abstract 2267: Inhibition of autophagy in hypoxic HT29 cells reverses hypoxia-induced resistance to oxaliplatin

BACKGROUND: We have shown previously that inhibition of JNK1 renders HT29 colon adenocarcinoma cells more sensitive to hypoxia and/or oxaliplatin due, in part, to impaired autophagy induction. We also showed that the autophagy inhibitor chloroquine sensitizes HT29 to oxaliplatin in vitro and in mouse xenograft model. PURPOSE: Here we investigate further by molecular approaches, including modulation of signaling through JNK, how inhibition of autophagy affects sensitivity of hypoxic colon cancer cells to oxaliplatin. We employed a panel of HT29-derived cell lines: lines stably expressing dominant negative constructs for either JNK1 (HTJ1.3) or JNK2 (HTJ2.2) singly, derivatives of these lines in which the other JNK gene is silenced by viral delivery of shRNA construct (HTJ1s2 and HTJ2s1), as well as HT29-derived lines with down-regulated BclX (HTBX) or Beclin-1 (HTB). RESULTS: We found that down-regulation of JNK1 leads to inhibition of autophagy accompanied by increase in apoptotic (versus necrosis) cell death. Clonogenic assays revealed higher resistance of HTJ1s2 cells to oxaliplatin under hypoxia, whereas HTJ2s1 cells demonstrated slight increase in sensitivity to the drug in this setting. Down-regulation of either Beclin-1 or BclX resulted in significant sensitization to oxaliplatin in oxic and, even more so, in hypoxic conditions (three-folds on average), while exerting differing effects on autophagy induction. CONCLUSIONS: Our data demonstrate that JNK1 plays an important role in autophagy induction under hypoxic conditions in the HT29 colon adenocarcinoma cell line and that its inhibition increases apoptotic cell death in this setting. Inhibition of autophagy induction by down-regulation of JNK1 and knock-down of Beclin-1 or BclX resulted in reversal of oxaliplatin resistance in hypoxic HT29 cells. These findings suggest that targeting these proteins may be of value in colon cancer treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2267. doi:1538-7445.AM2012-2267

Phase I, dose-escalation trial of the oral cyclin-dependent kinase 4/6 inhibitor PD 0332991, administered using a 21-day schedule in patients with advanced cancer

PURPOSE

To identify the dose-limiting toxicity (DLT) and maximum tolerated dose (MTD) of the first-in-class, oral CDK4/6 inhibitor PD 0332991 administered once daily for 21 of 28 days (3/1 schedule) in patients with retinoblastoma protein (Rb)-positive advanced solid tumors and to describe pharmacokinetic-pharmacodynamic relationships relative to drug effects.

EXPERIMENTAL DESIGN

This open-label phase I study (NCT00141297) enrolled patients who received PD 0332991 orally in six dose-escalation cohorts in a standard 3 + 3 design.

RESULTS

Forty-one patients were enrolled. DLTs were observed in five patients (12%) overall; at the 75, 125, and 150 mg once daily dose levels. The MTD and recommended phase II dose of PD 0332991 was 125 mg once daily. Neutropenia was the only dose-limiting effect. After cycle 1, grade 3 neutropenia, anemia, and leukopenia occurred in five (12%), three (7%), and one (2%) patient(s), respectively. The most common non-hematologic adverse events included fatigue, nausea, and diarrhea. Thirty-seven patients were evaluable for tumor response; 10 (27%) had stable disease for ≥4 cycles of whom six derived prolonged benefit (≥10 cycles). PD 0332991 was slowly absorbed (median T(max), 5.5 hours), and slowly eliminated (mean half-life was 25.9 hours) with a large volume of distribution (mean, 2,793 L). The area under the concentration-time curve increased linearly with dose. Using an E(max) model, neutropenia was shown to be proportional to exposure.

CONCLUSIONS

PD 0332991 warrants phase II testing at 125 mg once daily, at which dose neutropenia was the sole significant toxicity.

C-reactive protein as a predictor of postoperative infective complications following elective colorectal resection

AIM

C-reactive protein (CRP) may be useful in predicting postoperative complications [1]. We investigated the sensitivity and specificity of postoperative CRP for infective complications after elective colorectal surgery.

METHOD

One hundred and sixty consecutive patients (72 years old; interquartile range, 63-79) undergoing elective resection for colorectal cancer treated between September 2003 and October 2006 were studied. Details of the postoperative course were prospectively entered into a database. Of the 160 patients, 10 had incomplete CRP data and were excluded from further analysis.

RESULTS

Infective complications occurred in 21%, with an overall complication rate of 29%. Infective complications occurred as follows: respiratory (10), wound (9), urinary tract (2) and central line infection (1), anastomotic leakage (5), intra-abdominal abscess (3) and septicaemia of unknown origin (2). There were three postoperative deaths. The positive predictive value for infection of CRP > 145 mg/l on postoperative day 4 was 61%. The negative predictive value of CRP < 145 mg/l on postoperative day 4 for an infective complication was 96%.

CONCLUSION

A CRP > 145 mg/l on day 4 has high specificity and sensitivity for infective complications following elective colorectal resection.

Abstract 2521: Combining chemotherapy with autophagy inhibition: Phase I trial of dose-intense temozolomide and hydroxchloroquine in patients with advanced solid tumors

Background: Therapy-induced autophagy is a key resistance mechanism to alkylating chemotherapy. Hydroxychloroquine (HCQ) is an autophagy inhibitor that augments the antitumor efficacy of chemotherapy in preclinical models. To determine the safety and pharmacodynamic (PD) effects of combining an alkylating chemotherapy with an autophagy inhibitor, we conducted a phase I clinical trial of temozolomide (TMZ) and HCQ in patients with advanced solid tumors. Methods: This was a traditional 3+3 dose escalation study in which patients were treated with 2 weeks daily HCQ followed by combined treatment with TMZ 150 mg/m2 po qd for 7/ 14 days and continuous HCQ. Patients with solid tumors with any number of prior therapies were eligible. Because both drugs cross the blood brain barrier, patients with brain metastases were included. The primary objective was to determine the maximal tolerated dose (MTD) of HCQ in this combination. Secondary objectives included toxicity rate, response rate, and measurement of therapy-induced accumulation of autophagic vesicles (AV) in serial peripheral blood mononuclear cells (PBMC) and tumor tissue. Results: 27 patients including 10 with brain metastases were enrolled with 19 evaluable for toxicity and response. HCQ was successfully dose escalated from 200 mg daily to 600 mg bid in 5 cohorts. There was one dose limiting toxicity at 400 mg bid HCQ of grade 4 neutropenia &gt;7 days which lead to dose expansion. The 400 mg bid cohort was further expanded due to complete heart block in one patient that was thought to be unrelated to study drug. A grade 3 rash lead to dose expansion at 1000 mg daily. Anorexia, nausea, and fatigue were common grade 2 toxicities. In 12 patients with melanoma, partial response and stable disease was achieved in 2, and 3 patients respectively, including complete regression of multiple large extra-cranial tumors in a patient with brain metastases. One patient with 7 prior treatments for metastatic breast cancer with brain metastases had stable disease for 8 months. PD evidence of autophagy inhibition was observed by electron microscopy (EM) in PBMCs in individual patients but not across cohorts. In one patient with advanced melanoma, a post-progression FDG-PET scan demonstrated metabolic compromise and necrosis in the center of tumors, recapitulating preclinical models of autophagy inhibition. Conclusions: Dose- intense TMZ and HCQ demonstrated clinical activity, and a manageable safety profile in a population of patients enriched for brain metastases. Inconsistent evidence of autophagy inhibition in PBMC may reflect limited induction of autophagy by single agent temozolomide in surrogate tissues. Central metabolic compromise of tumor suggests FDG-PET can capture on-target effects of HCQ. The recommended phase II dose, final response rate and EM analysis of serial tumor biopsies will be presented.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2521. doi:10.1158/1538-7445.AM2011-2521

Abstract 4500: Combined mTOR inhibition and autophagy inhibition: Phase I trial of temsirolimus and hydroxchloroquine in patients with advanced solid tumors

Background: Therapy-induced autophagy may be a key resistance mechanism that explains the low rates of clinical benefit observed in trials of mTOR inhibitors in multiple cancers. For example, the mTOR inhibitor temsirolimus produced a 0% stable disease rate in a prior phase II trial in patients with metastatic melanoma. Hydroxychloroquine (HCQ) is an autophagy inhibitor that augments the antitumor efficacy of a number of anticancer therapies including mTOR inhibitors in preclinical models. To determine the safety and pharmacodynamic (PD) effects of combining an mTOR inhibitor with an autophagy inhibitor, we report the results of a phase I clinical trial of temsirolimus and HCQ in patients with advanced solid tumors. Methods: We conducted a traditional 3+3 phase I dose escalation clinical trial in which patients were treated with 1 week single agent temsirolimus 25 mg IV weekly followed by combined weekly temsirolimus with increasing doses of daily continuous HCQ. Patients with advanced solid tumors with any number of prior therapies were eligible. The primary objective was to determine the maximal tolerated dose (MTD) of HCQ in this combination. Secondary objectives included toxicity rate, response rate, measurement of therapy-induced accumulation of autophagic vesicles (AV) in serial peripheral blood mononuclear cells (PBMC) and tumor tissue, and pharmacokinetic (PK) analysis of temsirolimus, sirolimus and HCQ to explore drug interactions and establish a PK-PD relationship. A 12 patient expansion at the MTD or HCQ 600 mg bid (final planned dose level) in patients with metastatic melanoma with serial FDG-PET scans is planned. Results: 23 patients were enrolled with 14 evaluable for response and toxicity. The median number of prior treatments was 4. HCQ was successfully dose escalated from 200 mg daily to 600 mg bid in 4 cohorts. There was one dose limiting toxicity (DLT) at 200 mg HCQ, grade 4 thrombocytopenia with bleeding, that lead to dose expansion. The 800 mg dose cohort was also expanded due to a death from streptococcal pneumonia in month 3 of treatment. No additional bleeding, infections, or other DLTs were observed. Anorexia, nausea, and fatigue were common grade 2 toxicities. Stable disease was achieved in 10/14 evaluable patients, including 4/5 patients with metastatic melanoma. After 6 weeks of treatment, a significant accumulation of AV was observed in PBMC of patients treated with this combination compared to pretreatment samples providing PD evidence of consistent autophagy inhibition. Conclusions: The combination of temsirolimus and HCQ demonstrated significant clinical activity, and a manageable safety profile in a highly treatment-refractory patient population. PD evidence of autophagy inhibition was observed. The recommended phase II dose, PK-PD analysis, response rate, and FDG-PET results in the melanoma expansion will be presented.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4500. doi:10.1158/1538-7445.AM2011-4500

Abstract 2872: Induction of autophagy in hypoxic HT29 cells requires functional JNK1

BACKGROUND: Hypoxic HT29 colon cancer cell lines exhibit higher sensitivity to oxaliplatin when SEK1 function is impaired and higher resistance when MKK7 is down regulated (which in turn, cause more profound inhibition of JNK activation). We observed differential effects of JNK1/JNK2 modulation on oxaliplatin sensitivity of hypoxic HT29 cells to oxaliplatin treatment that implied a pro-survival function for JNK1. Further, we have shown that both oxaliplatin- and hypoxia-induced autophagy in these cells is diminished in the presence of JNK inhibitor SP600125, and that the cells are sensitized thereby.

PURPOSE: Here we investigate further how modulation of signaling through JNK influences autophagy in hypoxic HT29 cells treated with oxaliplatin, and expand the cellular model to additional colon cancer cell lines. We created a panel of HT29-derived cell lines stably expressing dominant negative constructs for SEK1 (HTS13), MKK7 (HTM9), JNK1 (HTJ1.3) and JNK2 (HTJ2.2). We also utilized 6 colon cancer cell lines (HCT116, LoVo, RKO1, SW480, DLD1 and HCT15) in which a dominant negative construct for JNK1 was introduced by viral delivery.

RESULTS: Our data demonstrate that in HTJ1.3 cells, hypoxic induction of autophagy is impaired. Silencing of JNK2 in these cells by viral delivery of shRNA does not affect either autophagy induction, or sensitivity to oxaliplatin. Downregulation of up-stream activators of JNK, as in the dnSEK1 or dnMKK7 derivatives, similarly does not affect autophagy induction, while still demonstrating differential effects on activation of JNK isoforms and its major target, c-Jun. Finally, we show that colon cancer cell lines differ in their ability initiate autophagy under hypoxia. Correspondingly, the introduction of dominant negative JNK1 causes some enhancement of oxaliplatin cytotoxicity in LoVo, RKO1 and HCT15 cell lines, which all demonstrate a greater propensity to autophagy under these circumstances.

CONCLUSIONS: Our data demonstrate that JNK1 plays a central role in autophagy induction under hypoxic conditions. Knockdown of JNK1 renders HT29 cells more sensitive to hypoxia due to impaired autophagy induction, and JNK2 is unable to substitute for JNK1 under these conditions. Our results also imply involvement of alternative JNK1 activators in autophagy induction by hypoxia. Finally, induction of autophagy and enhancement of oxaliplatin cytotoxicity, by this mechanism, appear to be model-specific in colon cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2872. doi:10.1158/1538-7445.AM2011-2872

CD40 agonists alter tumor stroma and show efficacy against pancreatic carcinoma in mice and humans

Immunosuppressive tumor microenvironments can restrain antitumor immunity, particularly in pancreatic ductal adenocarcinoma (PDA). Because CD40 activation can reverse immune suppression and drive antitumor T cell responses, we tested the combination of an agonist CD40 antibody with gemcitabine chemotherapy in a small cohort of patients with surgically incurable PDA and observed tumor regressions in some patients. We reproduced this treatment effect in a genetically engineered mouse model of PDA and found unexpectedly that tumor regression required macrophages but not T cells or gemcitabine. CD40-activated macrophages rapidly infiltrated tumors, became tumoricidal, and facilitated the depletion of tumor stroma. Thus, cancer immune surveillance does not necessarily depend on therapy-induced T cells; rather, our findings demonstrate a CD40-dependent mechanism for targeting tumor stroma in the treatment of cancer.

Interaction of sorafenib and cytochrome P450 isoenzymes in patients with advanced melanoma: a phase I/II pharmacokinetic interaction study

BACKGROUND

In vitro data indicate that the sorafenib is a moderate inhibitor of cytochrome P450 (CYP) enzymes, including CYP3A4, CYP2C19, and CYP2D6. This phase I/II study in patients with advanced melanoma evaluated the potential effect of sorafenib on the pharmacokinetics of midazolam, omeprazole, and dextromethorphan, specific substrates of CYP3A4, CYP2C19, and CYP2D6, respectively.

METHODS

Twenty-one patients received sorafenib 400 mg twice daily for 28 consecutive days. On days 1 and 28, a cocktail containing midazolam 2 mg, omeprazole 20 mg, and dextromethorphan 30 mg was administered. Pharmacokinetic analyses were performed on day 1 without sorafenib and day 28 after steady-state sorafenib exposure; sorafenib pharmacokinetics were evaluated on day 28. We defined an interaction to be excluded if the 90% confidence interval of the ratio of all day 28:day 1 analyses fell within a range from 0.80 to 1.25.

RESULTS

In all, 18 patients were evaluable. On day 28, area under the plasma concentration-time curve from time 0 to 12 h (AUC(0-12)) and maximum plasma concentration (C(max)) for sorafenib were 38.1 mg h/l and 4.9 mg/l, respectively. Day 28:day 1 ratios for AUC from time 0 extrapolated to infinity (AUC(0-inf)) and C(max) for midazolam were 0.85 and 0.98, respectively. Day 28:day 1 ratio for 5-OH-omeprazole:omeprazole plasma concentration at 3 h postdose was 1.26, slightly outside of the 0.80-1.25 range. Thus, an interaction could not be excluded, but is considered unlikely to be clinically significant. Day 28:day 1 ratio for dextromethorphan:dextrorphan concentration in urine was 0.94. Sorafenib had an acceptable safety profile. The most frequently observed grade 3-4 toxicities in cycle 1 included elevated lipase (19%) and hypertension (10%).

CONCLUSIONS

In this patient population, our results demonstrate that exposures of probes of CYP3A4, CYP2D6, or CYP2C19 activity are potentially altered by administration of sorafenib at 400 mg twice daily. However, these differences are sufficiently small that a clinically significant inhibition or induction of these important drug metabolizing P450 isoenzymes is unlikely. Clinical and, where possible, drug level monitoring may still be appropriate for drugs of narrow therapeutic range co-administered with sorafenib.

Phase 2 trial of bevacizumab, capecitabine, and oxaliplatin in treatment of advanced hepatocellular carcinoma

BACKGROUND

Anti-angiogenesis agents have shown effectiveness in treatment of hepatocellular carcinoma (HCC). It is important to investigate more effective and safe systemic treatment options for patients with advanced HCC. This phase 2 study was designed to determine the efficacy and toxicity of the combination of bevacizumab, capecitabine, and oxaliplatin in patients with advanced unresectable and untransplantable HCC.

METHODS

Chemotherapy-naive patients with advanced unresectable and untransplantable HCC were treated with bevacizumab 5 mg/kg and oxaliplatin 130 mg/m(2) on day 1 of each cycle, and capecitabine 825 mg/m² orally twice a day from days 1 to 14 of a 21-day cycle.

RESULTS

Forty patients were enrolled to the study, in which 40% had Child-Pugh B disease. Forty percent had an Eastern Cooperative Oncology Group performance status (PS) of 0, 55% had PS of 1, and 5% had PS of 2. Forty percent of patients had hepatitis B virus infection. The median progression-free survival was 6.8 months (95% CI, 3.4-9.1 months), and the median overall survival was 9.8 months (95% CI, 5.2-12.1 months). Eight patients (20%) achieved partial response; 23 patients had stable disease with overall 77.5% disease control rate. The combination was tolerable with limited grade 3/4 toxicity, mainly peripheral neurotoxicity and fatigue.

CONCLUSIONS

The combination appeared effective and safe, and the results were encouraging. Further investigation should be considered.

Abdominal Paragangliomas: Analysis of Surgeon's Experience

Abdominal paraganglioma is a rare endocrine tumor associated with genetic mutations, however, the ability to predict long-term risk of metastasis has not been clarified. The aim of this study was to examine the clinicopathological features and outcomes in patients undergoing surgery for an abdominal paraganglioma. A retrospective analysis was performed for all patients undergoing surgery for abdominal paragangliomas from one surgical department between 1998 and 2010. Clinical presentation, hormone secretion and clinical outcomes were examined. A total of 23 patients underwent surgery for abdominal paraganglioma with the most common presentation being hypertension. Median time to metastasis was 32 months with all patients developing disease progression having a rise in urine catecholamines. Patients with capsular invasion or predisposing genetic conditions are at a higher risk of having more aggressive disease. All patients with a diagnosis of paraganglioma should be screened for predisposing genetic abnormalities and postoperative follow-up must include routine urinary catecholamine assessment.

Long-term follow-up of patients with a painless inguinal hernia from a randomized clinical trial

BACKGROUND

Up to one-third of patients with an inguinal hernia have no symptoms from the hernia. The aim of this study was to determine the long-term outcome of patients with a painless inguinal hernia randomized to observation or operation.

METHODS

Some 160 men aged 55 years or more with a painless inguinal hernia were randomized to observation or operation between 2001 and 2003. All were invited to attend a research clinic at 6 and 12 months, and 5 years after randomization. Those unable to attend for clinical review were sent a questionnaire based on the clinical review pro forma.

RESULTS

After a median follow-up of 7.5 (range 6.2-8.2) years, 42 men had died (19 in the observation and 23 in the operation group); 46 of the 80 men randomized to observation had conversion to operation. The estimated conversion rate (using the Kaplan-Meier method) for the observation group was 16 (95 per cent confidence interval 9 to 26) per cent at 1 year, 54 (42 to 66) per cent 5 years and 72 (59 to 84) per cent at 7.5 years. The main reason for conversion was pain in 33 men, and two presented with an acute hernia. Sixteen men developed a new primary contralateral inguinal hernia and three had recurrent hernias. There have been 90 inguinal hernia repairs in the 80 patients randomized to surgery compared with 56 in those randomized to observation.

CONCLUSION

Most patients with a painless inguinal hernia develop symptoms over time. Surgical repair is recommended for medically fit patients with a painless inguinal hernia.

Inhibition of mutated, activated BRAF in metastatic melanoma

BACKGROUND

The identification of somatic mutations in the gene encoding the serine-threonine protein kinase B-RAF (BRAF) in the majority of melanomas offers an opportunity to test oncogene-targeted therapy for this disease.

METHODS

We conducted a multicenter, phase 1, dose-escalation trial of PLX4032 (also known as RG7204), an orally available inhibitor of mutated BRAF, followed by an extension phase involving the maximum dose that could be administered without adverse effects (the recommended phase 2 dose). Patients received PLX4032 twice daily until they had disease progression. Pharmacokinetic analysis and tumor-response assessments were conducted in all patients. In selected patients, tumor biopsy was performed before and during treatment to validate BRAF inhibition.

RESULTS

A total of 55 patients (49 of whom had melanoma) were enrolled in the dose-escalation phase, and 32 additional patients with metastatic melanoma who had BRAF with the V600E mutation were enrolled in the extension phase. The recommended phase 2 dose was 960 mg twice daily, with increases in the dose limited by grade 2 or 3 rash, fatigue, and arthralgia. In the dose-escalation cohort, among the 16 patients with melanoma whose tumors carried the V600E BRAF mutation and who were receiving 240 mg or more of PLX4032 twice daily, 10 had a partial response and 1 had a complete response. Among the 32 patients in the extension cohort, 24 had a partial response and 2 had a complete response. The estimated median progression-free survival among all patients was more than 7 months.

CONCLUSIONS

Treatment of metastatic melanoma with PLX4032 in patients with tumors that carry the V600E BRAF mutation resulted in complete or partial tumor regression in the majority of patients. (Funded by Plexxikon and Roche Pharmaceuticals.)

Phase II study of sorafenib in combination with docetaxel and cisplatin in the treatment of metastatic or advanced gastric and gastroesophageal junction adenocarcinoma: ECOG 5203

PURPOSE

The combination of sorafenib with chemotherapy is well-tolerated and is associated with encouraging response rates in several malignances. Both docetaxel and cisplatin are active in gastric cancer. A phase II study was conducted to determine the efficacy and toxicity of combined sorafenib, docetaxel, and cisplatin in patients with metastatic or advanced adenocarcinoma of stomach or gastroesophageal junction (GEJ).

PATIENTS AND METHODS

Forty-four chemotherapy-naïve patients with Eastern Cooperative Oncology Group performance status 0 or 1, of whom 80% had metastatic disease and two thirds had poorly differentiated gastric or GEJ adenocarcinoma, were enrolled. The treatment regimen was sorafenib 400 mg orally twice a day for 21 days, docetaxel 75 mg/m(2) intravenously on day 1, and cisplatin 75 mg/m(2) intravenously on day 1, repeated every 21 days. The primary end point was response rate to the combination. Toxicity, overall survival, and progression-free survival were assessed as secondary end points.

RESULTS

Eighteen of the 44 eligible and treated patients showed partial responses (41%; 90% CI, 28% to 54%). The median progression-free survival was 5.8 months (90% CI, 5.4 to 7.4 months). The median overall survival was 13.6 months (90% CI, 8.6 to 16.1 month). The major toxicity of this regimen was neutropenia, which reached grade 3 to 4 in 64% of patients. One patient experienced hemorrhage at the tumor site.

CONCLUSION

The combination of sorafenib, docetaxel, and cisplatin has an encouraging efficacy profile with tolerable toxicity. Additional studies of sorafenib with chemotherapy are warranted in gastric cancer.

Phase I dose-escalation study of recombinant human Apo2L/TRAIL, a dual proapoptotic receptor agonist, in patients with advanced cancer

PURPOSE

Apoptosis ligand 2/tumor necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL)-a member of the tumor necrosis factor cytokine family-induces apoptosis by activating the extrinsic pathway through the proapoptotic death receptors DR4 and DR5. Recombinant human Apo2L/TRAIL (rhApo2L/TRAIL) has broad potential as a cancer therapy. To the best of our knowledge, this is the first in-human clinical trial to assess the safety, tolerability, pharmacokinetics, and antitumor activity of multiple intravenous doses of rhApo2L/TRAIL in patients with advanced cancer.

PATIENTS AND METHODS

This phase I, open-label, dose-escalation study treated patients with advanced cancer with rhApo2L/TRAIL doses ranging from 0.5 to 30 mg/kg/d, with parallel dose escalation for patients without liver metastases and with normal liver function (cohort 1) and for patients with liver metastases and normal or mildly abnormal liver function (cohort 2). Doses were given daily for 5 days, with cycles repeating every 3 weeks. Assessments included adverse events (AEs), laboratory tests, pharmacokinetics, and imaging to evaluate antitumor activity.

RESULTS

Seventy-one patients received a mean of 18.3 doses; seven patients completed all eight treatment cycles. The AE profile of rhApo2L/TRAIL was similar in cohorts 1 and 2. The most common AEs were fatigue (38%), nausea (28%), vomiting (23%), fever (23%), anemia (18%), and constipation (18%). Liver enzyme elevations were concurrent with progressive metastatic liver disease. Two patients with sarcoma (synovial and undifferentiated) experienced serious AEs associated with rapid tumor necrosis. Two patients with chondrosarcoma experienced durable partial responses to rhApo2L/TRAIL.

CONCLUSION

At the tested schedule and dose range, rhApo2L/TRAIL was safe and well tolerated. Dose escalation achieved peak rhApo2L/TRAIL serum concentrations equivalent to those associated with preclinical antitumor efficacy.

Abstract 87: Differential effects of JNK1 and JNK2 on cell death in hypoxic colon cancer cell lines

BACKGROUND: We previously showed that hypoxic colon cancer cell lines exhibit higher sensitivity to oxaliplatin when SEK1 function is impaired, and greater resistance when MKK7 is down regulated. The MKK7 mutant lines exhibit more profound inhibition of JNK activation than those lacking SEK1, and their effects on the activation of JNK1 and JNK2 differ. The HT29 cells do not die readily by apoptosis under these conditions, and both oxaliplatin and hypoxia induce autophagy in these cells.

PURPOSE: The purpose of this study is to investigate further how modulation of signaling through JNK1 and JNK2 influences cell death pathways in hypoxic HT29 cells treated with oxaliplatin. For that, we employed HT29-derived cell lines stably expressing empty vector (HT.LX) and dominant negative constructs for JNK1 (HTJ1.3) and JNK2 (HTJ2.2).

RESULTS: We observed higher induction and activation of c-Jun in cells with dnJNK1, while introduction of dnJNK2 caused the opposite effect. Resistance to oxaliplatin under hypoxic conditions was also higher in the cell line with lowest c-Jun activation level (IC50 of 2.1 μM for HT.LX, 3 μM for HTJ2.2 and 0.8 μM for HTJ1.3), suggesting a pro-survival role for JNK1 under these conditions. Both oxaliplatin- and hypoxia-induced formation of autophagosomes was reduced significantly in HT29 cells treated with the JNK inhibitor SP600125. We also found differential sensitivity of these cell lines to an inhibitor of autophagy, chloroquine (CQ): HTJ1.3 and HTJ2.2 cell lines were slightly more resistant to CQ under normal conditions, as compared to parental line, but under hypoxia all of the lines demonstrated higher sensitivity to the drug. Notably, in light of the role of JNK1 in activating autophagy, cells with diminished JNK1 activity were the most sensitive to CQ under hypoxia. Moreover, when we treated the cell lines with 5 μM of CQ under hypoxia/reoxygenation, inhibition of autophagy and induction of apoptosis were most significant in dnJNK1-expressing cells. This effect of JNK1 down-regulation is specific to hypoxia, since the constructs do not differ in sensitivity to CQ and oxaliplatin in combination.

CONCLUSIONS: Our data demonstrate the differential effects of JNK1/JNK2 modulation on cell death of hypoxic HT29 cells treated with oxaliplatin or chloroquine, and imply pro-survival function for JNK1 versus JNK2 under these conditions.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 87.

Efficacy and safety of sorafenib in a subset of patients with advanced soft tissue sarcoma from a Phase II randomized discontinuation trial

AIM

Phase II multi-disease randomized discontinuation trial to assess the safety and efficacy of sorafenib including patients with advanced soft tissue sarcoma (STS).

METHODS

Sorafenib (400 mg twice daily) was initially administered for 12 weeks. Patients with: ≥25% tumour shrinkage continued sorafenib; ≥25% tumour growth discontinued; other patients were randomized and received sorafenib or placebo.

RESULTS

Twenty-six patients (median age 55 years) were enrolled. Common drug-related adverse events, including fatigue, hand-foot skin reaction, rash or gastrointestinal disturbances, were manageable, reversible and generally low grade. Fatigue, skin toxicity, nausea, diarrhoea and hypertension occurred at grade ≥3 in 19% of patients. After 12 weeks eight (31%) patients had not progressed. Three patients who experienced tumour shrinkage and continued on sorafenib, and five (19%) were randomized either to continue sorafenib or to receive placebo. Of the three patients randomized to sorafenib, one achieved a partial response and two had SD. Overall one patient achieved a partial response and three further patients achieved minor responses.

CONCLUSIONS

There was evidence of disease activity in STS as defined by tumor regressions including one objective partial response. Further investigation in STS is warranted.

A risk variant in an miR-125b binding site in BMPR1B is associated with breast cancer pathogenesis

MicroRNAs regulate diverse cellular processes and play an integral role in cancer pathogenesis. Genomic variation within miRNA target sites may therefore be important sources for genetic differences in cancer risk. To investigate this possibility, we mapped HapMap single nucleotide polymorphisms (SNP) to putative miRNA recognition sites within genes dysregulated in estrogen receptor-stratified breast tumors and used local linkage disequilibrium patterns to identify high-ranking SNPs in the Cancer Genetic Markers of Susceptibility (CGEMS) breast cancer genome-wide association study for further testing. Two SNPs, rs1970801 and rs11097457, scoring in the top 100 from the CGEMS study, were in strong linkage disequilibrium with rs1434536, an SNP that resides within a miR-125b target site in the 3' untranslated region of the bone morphogenic receptor type 1B (BMPR1B) gene encoding a transmembrane serine/threonine kinase. We validated the CGEMS association findings for rs1970801 in an independent cohort of admixture-corrected cases identified from families with multiple case histories. Subsequent association testing of rs1434536 for these cases and CGEMS controls with imputed genotypes supported the association. Furthermore, luciferase reporter assays and overexpression of miR-125b-mimics combined with quantitative reverse transcription-PCR showed that BMPR1B transcript is a direct target of miR-125b and that miR-125b differentially regulates the C and T alleles of rs1434536. These results suggest that allele-specific regulation of BMPR1B by miR-125b explains the observed disease risk. Our approach is general and can help identify and explain the mechanisms behind disease association for alleles that affect miRNA regulation.

The terrible choice: re-evaluating hospice eligibility criteria for cancer

PURPOSE

To be eligible for the Medicare Hospice Benefit, cancer patients with a life expectancy of 6 months or less must give up curative treatment. Our goal was to determine whether willingness to make this choice identifies patients with greater need for hospice services.

PATIENTS AND METHODS

Three hundred patients with cancer and 171 family members were recruited from six oncology practices. Respondents completed conjoint interviews in which their perceived need for five hospice services was calculated from the choices they made among combinations of services. Patients' preferences for treatment were measured, and patients were followed for 6 months or until death.

RESULTS

Thirty-eight patients (13%) said they would not want cancer treatment even if it offered an almost 100% chance of 6-month survival. These patients, who would have been eligible for hospice, did not have greater perceived need for hospice services compared with other patients (n = 262; mean, 1.75 v 1.98; Wilcoxon rank sum test, P = .46), nor did their family members (mean, 1.95 v 2.04; Wilcoxon rank sum test, P = .80). Instead, independent predictors of patients' perceived need for hospice services included African American ethnicity, less social support, worse functional status, and a greater burden of psychological symptoms. For families, predictors included caregiver burden, worse self-reported health, working outside the home, and caring for a patient with worse functional status.

CONCLUSION

The requirement that patients forgo life-sustaining treatment does not identify patients with greater perceived need for hospice services. Other characteristics offer a better way to identify the patients who are most likely to benefit from hospice.

Strong signature of natural selection within an FHIT intron implicated in prostate cancer risk

Previously, a candidate gene linkage approach on brother pairs affected with prostate cancer identified a locus of prostate cancer susceptibility at D3S1234 within the fragile histidine triad gene (FHIT), a tumor suppressor that induces apoptosis. Subsequent association tests on 16 SNPs spanning approximately 381 kb surrounding D3S1234 in Americans of European descent revealed significant evidence of association for a single SNP within intron 5 of FHIT. In the current study, re-sequencing and genotyping within a 28.5 kb region surrounding this SNP further delineated the association with prostate cancer risk to a 15 kb region. Multiple SNPs in sequences under evolutionary constraint within intron 5 of FHIT defined several related haplotypes with an increased risk of prostate cancer in European-Americans. Strong associations were detected for a risk haplotype defined by SNPs 138543, 142413, and 152494 in all cases (Pearson's chi(2) = 12.34, df 1, P = 0.00045) and for the homozygous risk haplotype defined by SNPs 144716, 142413, and 148444 in cases that shared 2 alleles identical by descent with their affected brothers (Pearson's chi(2) = 11.50, df 1, P = 0.00070). In addition to highly conserved sequences encompassing SNPs 148444 and 152413, population studies revealed strong signatures of natural selection for a 1 kb window covering the SNP 144716 in two human populations, the European American (pi = 0.0072, Tajima's D = 3.31, 14 SNPs) and the Japanese (pi = 0.0049, Fay & Wu's H = 8.05, 14 SNPs), as well as in chimpanzees (Fay & Wu's H = 8.62, 12 SNPs). These results strongly support the involvement of the FHIT intronic region in an increased risk of prostate cancer.