A phase 2 study of MK-2206 in patients with incurable adenoid cystic carcinoma (Alliance A091104)

BACKGROUND

Recurrent/metastatic adenoid cystic carcinoma (ACC) is a rare, incurable disease. MYB is a putative oncogenic driver in ACC that is often overexpressed through an MYB-NFIB rearrangement. The authors hypothesized that AKT inhibition with the allosteric inhibitor MK-2206 could decrease MYB expression and induce tumor regression in patients with incurable ACC (ClinicalTrials.gov identifier NCT01604772).

METHODS

Patients with progressive, incurable ACC were enrolled and received MK-2206 150 mg weekly; escalation to 200 mg was allowed. The primary end point was confirmed response. Secondary end points were progression-free survival, overall survival, and safety. An exploratory analysis evaluating the effect of MK-2206 on MYB expression was conducted in a subset of patients.

RESULTS

Sixteen patients were enrolled, and 14 were evaluable for efficacy. No confirmed responses were observed. Thirteen patients had stable disease, and one had disease progression as their best response. The median progression-free survival was 9.7 months (95% CI, 3.8-11.8 months), and the median overall survival was 18.0 months (95% CI, 11.8-29.9 months). Nine of 16 patients (56%) had at least one grade 3 treatment-related adverse event, and the most common were rash (38%), fatigue (19%), decreased lymphocyte count (13%), and hyperglycemia (13%). Twelve of 14 tumors (86%) had detectable MYB expression by immunohistochemistry, and seven of 14 tumors (50%) had an MYB-NFIB gene rearrangement. Serial biopsies revealed decreased MYB levels with MK-2206 in four of five patients.

CONCLUSIONS

MK-2206 failed to induce clinical responses in patients with incurable ACC. AKT inhibition may diminish MYB protein levels, although the effect was highly variable among patients. Novel approaches to target MYB in ACC are needed.

A phase II study of bevacizumab and temsirolimus in advanced extra-pancreatic neuroendocrine tumors

We assessed the efficacy and safety of combining bevacizumab with temsirolimus in patients with advanced extra-pancreatic neuroendocrine tumors. This NCI-sponsored multicenter, open-label, phase II study (NCT01010126) enrolled patients with advanced, recurrent, or metastatic extra-pancreatic neuroendocrine tumors. All patients were treated with temsirolimus and bevacizumab until disease progression or unacceptable toxicity. Temsirolimus 25 mg was administered i.v. on days 1, 8, 15, and 22 and bevacizumab 10 mg/kg i.v. on days 1 and 15 of a 4-week cycle. Discontinuation of temsirolimus or bevacizumab did not require discontinuation of the other agent. The primary endpoints were objective response rate and 6-month progression-free survival rate. Fifty-nine patients were enrolled in this study, and 54 were evaluated for efficacy and adverse events. While median progression-free survival was 7.1 months, the median duration of treatment with temsirolimus was 3.9 months and that with bevacizumab was 3.5 months. The objective response rate of combination therapy was 2%, and 6-month progression-free survival was 48%. The most frequently reported grade 3-4 adverse events included fatigue (13%), hypertension (13%), and bleeding (13%). Close to 54% of the patients discontinued treatment due to adverse events, refusal of further treatment, or treatment delays. Three deaths occurred in the study, of which two were due to treatment-related bowel perforations. Given the minimal efficacy and increased toxicity seen with the combination of bevacizumab and temsirolimus, we do not recommend the use of this regimen in patients with advanced extra-pancreatic neuroendocrine tumors.

Phase I study of cediranib, an oral VEGFR inhibitor, in combination with selumetinib, an oral MEK inhibitor, in patients with advanced solid malignancies

PURPOSE

Targeting the vascular endothelial growth factor (VEGF) pathway improves progression free survival in multiple advanced malignancies but durable responses are uncommon. Inhibition of the VEGF pathway at multiple levels of signal transduction may improve clinical outcomes. Preclinical data with cediranib, an inhibitor of all 3 VEGF receptors, in combination with selumetinib, an inhibitor of MEK 1/2, demonstrated improved tumor control experimentally. This phase I trial was designed to test the two agents in combination to evaluate the tolerability, safety and assess disease response.

METHODS

Patients with advanced solid malignancies were enrolled into this phase I trial. Cediranib and selumetinib were dosed using a toxicity-adaptive isotonic design for the dose escalation/de-escalation of each agent. Both cediranib and selumetinib were administered daily and continuously. Cycles were 28 days in length.

RESULTS

Eighteen patients were enrolled. At all dose levels, dose limiting toxicities (DLT) were observed, which limited dose escalation and further evaluation. The maximum tolerated dose of cediranib and selumetinib in combination could not be determined. The best response of stable disease was observed in eight patients.

CONCLUSIONS

Cediranib and selumetinib in combination on a continuous schedule was not tolerable, with patients experiencing cardiovascular and other DLTs. Intermittent schedules may be needed to establish a safe and tolerable combination of cediranib and selumetinib.

Clinicopathological and Molecular Characteristics of Early-Onset Stage III Colon Adenocarcinoma: An Analysis of the ACCENT Database

BACKGROUND

Colon cancer (CC) incidence in young adults (age 20-49 years), termed early-onset CC (EO-CC), is increasing.

METHODS

Individual patient data on 35 713 subjects with stage III colon cancer from 25 randomized studies in the Adjuvant Colon Cancer ENdpoint database were pooled. The distributions of demographics, clinicopathological features, biomarker status, and outcome data were summarized by age group. Overall survival, disease-free survival, time to recurrence, and survival after recurrence were assessed by Kaplan-Meier curves and Cox models stratified by treatment arms within studies, adjusting for sex, race, body mass index, performance status, disease stage, grade, risk group, number of lymph nodes examined, disease sidedness, and molecular markers. All statistical tests were 2-sided.

RESULTS

Using a 5% difference between age groups as the clinically meaningful cutoff, patients with stage III EO-CC had similar sex, race, performance status, risk group, tumor sidedness, and T stage compared with patients with late-onset CC (age 50 years and older). EO-CC patients were less likely to be overweight (30.2% vs 36.2%) and more commonly had 12 or more lymph nodes resected (69.5% vs 58.7%). EO-CC tumors were more frequently mismatch repair deficient (16.4% vs 11.5%) and less likely to have BRAFV600E (5.6% vs 14.0%), suggesting a higher rate of Lynch syndrome in EO-CC. Patients with EO-CC had statistically significantly better overall survival (hazard ratio [HR] = 0.81, 95% confidence interval [CI] = 0.74 to 0.89; P < .001), disease-free survival (HR = 0.91, 95% CI = 0.84 to 0.98; P = .01), and survival after recurrence (HR = 0.88, 95% CI = 0.80 to 0.97; P = .008) in the analysis without molecular markers; however, age at onset of CC lost its prognostic value when outcome was adjusted for molecular markers.

CONCLUSION

Tumor biology was found to be a more important prognostic factor than age of onset among stage III colon cancer patients in the Adjuvant Colon Cancer ENdpoint database.

Microsatellite Instability in Patients With Stage III Colon Cancer Receiving Fluoropyrimidine With or Without Oxaliplatin: An ACCENT Pooled Analysis of 12 Adjuvant Trials

PURPOSE

In patients with stage III colon cancer (CC) whose tumors demonstrate microsatellite instability (MSI), the efficacy of adjuvant fluoropyrimidine (FP) with or without oxaliplatin has not been clearly demonstrated and the prognostic value of MSI remains uncertain.

MATERIALS AND METHODS

Individual patient data from the ACCENT database were used to evaluate the effect of FP with or without oxaliplatin on disease-free survival (DFS) and overall survival (OS) among patients with MSI stage III CC and the prognostic value of MSI in patients treated with FP plus oxaliplatin, by stratified Cox models adjusted for demographic and clinicopathological factors.

RESULTS

MSI status was available for 5,457 patients (609 MSI, 11.2%; 4848 microsatellite stable [MSS], 88.8%) from 12 randomized clinical trials (RCTs). Oxaliplatin significantly improved OS of MSI patients from the two RCTs testing FP with or without oxaliplatin (n = 185; adjusted hazard ratio [aHR] = 0.52, 95% CI, 0.28 to 0.93). Among the 4,250 patients treated with FP plus oxaliplatin (461 MSI and 3789 MSS), MSI was associated with better OS in the N1 group compared with MSS (aHR = 0.66; 95% CI, 0.46 to 0.95) but similar survival in the N2 population (aHR = 1.13; 95% CI, 0.86 to 1.48; P interaction = .029). The main independent prognosticators of MSI patients treated with FP plus oxaliplatin were T stage (aHR = 2.09; 95% CI, 1.29 to 3.38) and N stage (aHR = 3.57; 95% CI, 2.32 to 5.48). Similar results were observed for DFS in all analyses.

CONCLUSION

Adding oxaliplatin to FP improves OS and DFS in patients with MSI stage III CC. Compared with MSS, MSI patients experienced better outcomes in the N1 group but similar survival in the N2 group.

Targeting of the Hedgehog/GLI and mTOR pathways in advanced pancreatic cancer, a phase 1 trial of Vismodegib and Sirolimus combination

BACKGROUND/OBJECTIVES

Preclinical data indicated a functional and molecular interaction between Hedgehog (HH)/GLI and PI3K-AKT-mTOR pathways promoting pancreatic ductal adenocarcinoma (PDAC). A phase I study was conducted of Vismodegib and Sirolimus combination to evaluate maximum tolerated dose (MTD) and preliminary anti-tumor efficacy.

METHODS

Cohort I included advanced solid tumors patients following a traditional 3 + 3 design. Vismodegib was orally administered at 150 mg daily with Sirolimus starting at 3 mg daily, increasing to 6 mg daily at dose level 2. Cohort II included only metastatic PDAC patients. Anti-tumor efficacy was evaluated every two cycles and target assessment at pre-treatment and after a single cycle.

RESULTS

Nine patient were enrolled in cohort I and 22 patients in cohort II. Twenty-eight patients were evaluated for dose-limiting toxicities (DLTs). One DLT was observed in each cohort, consisting of grade 2 mucositis and grade 3 thrombocytopenia. The MTD for Vismodegib and Sirolimus were 150 mg daily and 6 mg daily, respectively. The most common grade 3-4 toxicities were fatigue, thrombocytopenia, dehydration, and infections. A total of 6 patients had stable disease. No partial or complete responses were observed. Paired biopsy analysis before and after the first cycle in cohort II consistently demonstrated reduced GLI1 expression. Conversely, GLI and mTOR downstream targets were not significantly affected.

CONCLUSIONS

The combination of Vismodegib and Sirolimus was well tolerated. Clinical benefit was limited to stable disease in a subgroup of patients. Targeting efficacy demonstrated consistent partial decreases in HH/GLI signaling with limited impact on mTOR signaling. These findings conflict with pre-clinical models and warrant further investigations.

An International Phase 2 Study of Pazopanib in Progressive and Metastatic Thyroglobulin Antibody Negative Radioactive Iodine Refractory Differentiated Thyroid Cancer

Introduction: Multikinase inhibitors have clinical activity in radioactive iodine refractory (RAIR) differentiated thyroid cancers (DTCs) but are not curative; optimal management and salvage therapies remain unclear. This study assessed clinical effects of pazopanib therapy in RAIR-DTC patients with progressive disease, examining in parallel biomarker that might forecast/precede therapeutic response. Methods: Assessment of responses and toxicities and of any association between thyroglobulin (Tg) changes cycle 1 and RECIST (response evaluation criteria in solid tumors) response to pazopanib therapy were prospectively undertaken in Tg antibody negative RAIR-DTC patients. RECIST progressive metastatic disease <6 months preceding enrollment was required. With a sample size of 68 (assuming 23 attaining partial response [PR]), there would be 90% chance of detecting a difference of >30% when the proportion of patients attaining PR whose Tg values decrease by >50% is >50% cycle 1 (one-sided α = 0.10, two sample test of proportions). Mean corpuscular volume (MCV) change or mutational status or pretreatment were also explored as early correlates of eventual RECIST response. Results: From 2009 to 2011, 60 individuals were treated and evaluated; (one additional patient withdrew; another was found ineligible before therapy initiation); 91.7% had previous systemic therapy beyond RAI. Adverse events included one death (thromboembolic) deemed possibly pazopanib associated. Twenty-two confirmed RECIST PRs resulted (36.7%, confidence interval; CI [24.6-50.1]); mean administered 4-week cycles was 10. Among 44 fully accessible patients, the Tg nadir was greater among the 20 attaining PR (median: -86.8%; interquartile range [IQR]: -90.7% to -70.9%) compared with the 28 who did not (median: -69.0%; IQR: -78.1% to -27.7%, Wilcoxon rank-sum test: p = 0.002). However, the difference in the proportion of PRs among those whose Tg fell ≥50% after cycle 1 versus those that did not were not significantly correlated (-23.5% [CI: -55.3 to 8.3]; Fisher's exact test p-value = 0.27). RECIST response was also not correlated with/predicted by early MCV change, receipt of prior therapy, or tumor mutational status. Conclusions: This trial prospectively confirmed pazopanib to have clinical activity and manageable toxicities in patients with progressive RAIR-DTC. Response to pazopanib, however, was not robustly forecast by early associated changes in Tg or MCV, by prior therapy, or by tumor mutational status. ClinicalTrials.gov NCT00625846.

Antitumor Activity of Nivolumab in Recurrent and Metastatic Nasopharyngeal Carcinoma: An International, Multicenter Study of the Mayo Clinic Phase 2 Consortium (NCI-9742)

Purpose This multinational study evaluated the antitumor activity of nivolumab in nasopharyngeal carcinoma (NPC). Tumor and plasma-based biomarkers were investigated in an exploratory analysis. Patients and Methods Patients with multiply pretreated recurrent or metastatic NPC were treated with nivolumab until disease progression. The primary end point was objective response rate (ORR) and secondary end points included survival and toxicity. The expression of programmed death-ligand 1 (PD-L1) and human leukocyte antigens A and B in archived tumors and plasma clearance of Epstein-Barr virus DNA were correlated with ORR and survival. Results A total of 44 patients were evaluated and the overall ORR was 20.5% (complete response, n = 1; partial response, n = 8). Nine patients received nivolumab for > 12 months (20%). The 1-year overall survival rate was 59% (95% CI, 44.3% to 78.5%) and 1-year progression-free survival (PFS) rate was 19.3% (95% CI, 10.1% to 37.2%). There was no statistical correlation between ORR and the biomarkers; however, a descriptive analysis showed that the proportion of patients who responded was higher among those with PD-L1 positive tumors (> 1% expression) than those with PD-L1-negative tumors. The loss of expression of one or both human leukocyte antigen class 1 proteins was associated with better PFS than when both proteins were expressed (1-year PFS, 30.9% v 5.6%; log-rank P = .01). There was no association between survival and PD-L1 expression or plasma Epstein-Barr virus DNA clearance. There was no unexpected toxicity to nivolumab. Conclusion Nivolumab has promising activity in NPC and the 1-year overall survival rate compares favorably with historic data in similar populations. Additional evaluation in a randomized setting is warranted. The biomarker results were hypothesis generating and validation in larger cohorts is needed.

Combination epigenetic therapy in metastatic colorectal cancer (mCRC) with subcutaneous 5-azacitidine and entinostat: a phase 2 consortium/stand up 2 cancer study

Purpose

Therapy with demethylating agent 5-azacitidine and histone deacetylase inhibitor entinostat shows synergistic re-expression of tumor-suppressor genes and growth inhibition in colorectal (CRC) cell lines and in vivo studies.

Experimental Design

We conducted a phase II, multi-institutional study of the combination in metastatic CRC patients. Subcutaneous azacitidine was administered at 40 mg/m2 days 1-5 and 8-10 and entinostat was given 7 mg orally on days 3 and 10. An interim analysis indicated toxicity crossed the pre-specified safety boundary but was secondary to disease. A 2^nd cohort with added eligibility restrictions was accrued: prior therapies were limited to no more than 2 or 3 (KRAS-mutated and KRAS-wildtype cancers, respectively) and <30% of liver involvement. The primary endpoint was RECIST response. Serial biopsies were performed at baseline and after 2 cycles of therapy.

Results

Forty-seven patients were enrolled (24:Cohort 1, 23:Cohort 2). Patients were heavily pre-treated (median prior therapies 4: Cohort 1 and 2.5: cohort 2). No responses were observed. Median progression-free survival was 1.9 months; overall survival was 5.6 and 8.3 months in Cohorts 1 and 2, respectively. Toxicity was tolerable and as expected. Unsupervised cluster analysis of serial tumor biopsies suggested greater DNA demethylation in patients with PFS above the median.

Conclusion

In this first trial of CRC patients with combination epigenetic therapy, we show tolerable therapy without significant clinical activity as determined by RECIST responses. Reversal of hypermethylation was seen in a subset of patients and correlated with improved PFS.

A Phase I Clinical Trial of the Poly(ADP-ribose) Polymerase Inhibitor Veliparib and Weekly Topotecan in Patients with Solid Tumors

Purpose: To determine the dose limiting toxicities (DLT), maximum tolerated dose (MTD), and recommended phase II dose (RP2D) of veliparib in combination with weekly topotecan in patients with solid tumors. Correlative studies were included to assess the impact of topotecan and veliparib on poly(ADP-ribose) levels in peripheral blood mononuclear cells, serum pharmacokinetics of both agents, and potential association of germline repair gene mutations with outcome.Experimental Design: Eligible patients had metastatic nonhematologic malignancies with measurable disease. Using a 3 + 3 design, patients were treated with veliparib orally twice daily on days 1-3, 8-10, and 15-17 and topotecan intravenously on days 2, 9, and 16 every 28 days. Tumor responses were assessed by RECIST.Results: Of 58 patients enrolled, 51 were evaluable for the primary endpoint. The MTD and RP2D was veliparib 300 mg twice daily on days 1-3, 8-10, and 15-17 along with topotecan 3 mg/m2 on days 2, 9, and 16 of a 28-day cycle. DLTs were grade 4 neutropenia lasting >5 days. The median number of cycles was 2 (1-26). The objective response rate was 10%, with 1 complete and 4 partial responses. Twenty-two patients (42%) had stable disease ranging from 4 to 26 cycles. Patients with germline BRCA1, BRCA2, or RAD51D mutations remained on study longer than those without homologous recombination repair (HRR) gene mutations (median 4 vs. 2 cycles).Conclusions: Weekly topotecan in combination with veliparib has a manageable safety profile and appears to warrant further investigation. Clin Cancer Res; 24(4); 744-52. ©2017 AACR.

A Phase II Trial of Neoadjuvant MK-2206, an AKT Inhibitor, with Anastrozole in Clinical Stage II or III PIK3CA-Mutant ER-Positive and HER2-Negative Breast Cancer

Purpose: Hyperactivation of AKT is common and associated with endocrine resistance in estrogen receptor-positive (ER⁺) breast cancer. The allosteric pan-AKT inhibitor MK-2206 induced apoptosis in PIK3CA-mutant ER⁺ breast cancer under estrogen-deprived condition in preclinical studies. This neoadjuvant phase II trial was therefore conducted to test the hypothesis that adding MK-2206 to anastrozole induces pathologic complete response (pCR) in PIK3CA mutant ER⁺ breast cancer.Experimental Design: Potential eligible patients with clinical stage II/III ER⁺/HER2^- breast cancer were preregistered and received anastrozole (goserelin if premenopausal) for 28 days in cycle 0 pending tumor PIK3CA sequencing. Patients positive for PIK3CA mutation in the tumor were eligible to start MK-2206 (150 mg orally weekly, with prophylactic prednisone) on cycle 1 day 2 (C1D2) and to receive a maximum of four 28-day cycles of combination therapy before surgery. Serial biopsies were collected at preregistration, C1D1 and C1D17.Results: Fifty-one patients preregistered and 16 of 22 with PIK3CA-mutant tumors received study drug. Three patients went off study due to C1D17 Ki67 >10% (n = 2) and toxicity (n = 1). Thirteen patients completed neoadjuvant therapy followed by surgery. No pCRs were observed. Rash was common. MK-2206 did not further suppress cell proliferation and did not induce apoptosis on C1D17 biopsies. Although AKT phosphorylation was reduced, PRAS40 phosphorylation at C1D17 after MK-2206 persisted. One patient acquired an ESR1 mutation at surgery.Conclusions: MK-2206 is unlikely to add to the efficacy of anastrozole alone in PIK3CA-mutant ER⁺ breast cancer and should not be studied further in the target patient population. Clin Cancer Res; 23(22); 6823-32. ©2017 AACR.

First-in-Human Phase I Study of the Tamoxifen Metabolite Z-Endoxifen in Women With Endocrine-Refractory Metastatic Breast Cancer

Purpose Endoxifen is a tamoxifen metabolite with potent antiestrogenic activity. Patients and Methods We performed a phase I study of oral Z-endoxifen to determine its toxicities, maximum tolerated dose (MTD), pharmacokinetics, and clinical activity. Eligibility included endocrine-refractory, estrogen receptor-positive metastatic breast cancer. An accelerated titration schedule was applied until moderate or dose-limiting toxicity occurred, followed by a 3+3 design and expansion at 40, 80, and 100 mg per day. Tumor DNA from serum (circulating cell free [cf); all patients] and biopsies [160 mg/day and expansion]) was sequenced. Results Of 41 enrolled patients, 38 were evaluable for MTD determination. Prior endocrine regimens during which progression occurred included aromatase inhibitor (n = 36), fulvestrant (n = 21), and tamoxifen (n = 15). Patients received endoxifen once daily at seven dose levels (20 to 160 mg). Dose escalation ceased at 160 mg per day given lack of MTD and endoxifen concentrations > 1,900 ng/mL. Endoxifen clearance was unaffected by CYP2D6 genotype. One patient (60 mg) had cycle 1 dose-limiting toxicity (pulmonary embolus). Overall clinical benefit rate (stable > 6 months [n = 7] or partial response by RECIST criteria [n = 3]) was 26.3% (95% CI, 13.4% to 43.1%) including prior tamoxifen progression (n = 3). cfDNA mutations were observed in 13 patients ( PIK3CA [n = 8], ESR1 [n = 5], TP53 [n = 4], and AKT [n = 1]) with shorter progression-free survival ( v those without cfDNA mutations; median, 61 v 132 days; log-rank P = .046). Clinical benefit was observed in those with ESR1 amplification (tumor; 80 mg/day) and ESR1 mutation (cfDNA; 160 mg/day). Comparing tumor biopsies and cfDNA, some mutations ( PIK3CA, TP53, and AKT) were undetected by cfDNA, whereas cfDNA mutations ( ESR1, TP53, and AKT) were undetected by biopsy. Conclusion In endocrine-refractory metastatic breast cancer, Z-endoxifen provides substantial drug exposure unaffected by CYP2D6 metabolism, acceptable toxicity, and promising antitumor activity.

Akt inhibitor MK-2206 in combination with bendamustine and rituximab in relapsed or refractory chronic lymphocytic leukemia: Results from the N1087 alliance study

Akt is a downstream target of B cell receptor signaling and is a central regulator of CLL cell survival. We aim to investigate the safety and efficacy of the Akt inhibitor MK-2206 in combination with bendamustine and rituximab (BR) in relapsed and/or refractory CLL in a phase I/II study. A standard phase I design was used with cohorts of three plus three patients to determine the maximum tolerated dose (MTD) of MK-2206 in combination with BR in relapsed CLL. Single-agent MK-2206 (weekly dosed) was administered one-week in advance before BR on cycle 1 and subsequently was given with BR at the same time for cycle 2-6. Phase II employed the MTD of MK-2206 with BR to evaluate safety and efficacy of this study combination. Thirteen relapsed/refractory CLL were treated for maximal 6-cycle of therapy. The maximum tolerated dose of MK-2206 was 90 mg by mouth once weekly. The most common grade 3/4 adverse events were neutropenia (46%), febrile neutropenia (23%), rash (15%), diarrhea (15%), and thrombocytopenia (15%). Overall response rate was 92% with a median progression free survival and treatment free survival of 16 and 24 months, respectively. Five patients (38%) achieved complete remission or complete remission with incomplete count recovery, two of whom were MRD negative. The efficacy and tolerability of this combination indicates that Akt inhibition combined with chemoimmunotherapy is a promising novel treatment combination in CLL and deserves further prospective clinical trial.

A hierarchical Bayesian design for randomized Phase II clinical trials with multiple groups

Enhanced knowledge of the biological and genetic basis of cancer is re-defining the target population for new treatments. In oncology, potential targets for a new therapeutic agent often include various solid and hematologic malignancies that share common signaling pathways. New agents are often tested in multiple tumor types across which information can be borrowed. We propose a hierarchical Bayesian design (HBD) to simultaneously test a novel agent in multiple groups for randomized Phase II clinical trials with binary endpoints. Compared to parallel design for individual tumor groups, the HBD has greatly reduced sample size. Therefore, this improves efficiency and decreases the financial cost of conducting randomized Phase II clinical trials. An R package hbdct has been developed to implement the HBD and streamline the sample size calibration.

Evaluation of tumor and circulating cell free (cf) DNA mutations in women with hormone refractory metastatic breast cancer (MBC) enrolled in a phase I study of Z-endoxifen (MC093C)

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Background: In estrogen receptor (ER) positive MBC, mutations (e.g. ESR1), identified from tumor biopsies or cfDNA, confer resistance. The concordance between mutations observed in tumor and cfDNA and the implications for response to Z-endoxifen, a potent anti-estrogen, are unknown. Methods: We previously conducted a phase I trial of Z-endoxifen in endocrine refractory, ER positive MBC. Seven dose levels were considered ranging from 20 to 160 mg/day followed by expansion cohorts (EC) of 40, 80, and 100 mg/day. Pretreatment blood samples (all pts) and fresh tumor biopsies (EC) were collected prospectively. Tumor and cfDNA were evaluated by targeted NGS. Results: 41 pts (38 evaluable) were enrolled. Prior endocrine therapy included aromatase inhibitors (37/38, 97%), fulvestrant (22/38, 58%) and tamoxifen (26/38, 68%). Substantial endoxifen exposure without DLTs at doses above 80 mg/day led to a halt in dose escalation and opening of the EC. Overall clinical benefit (stable > 6 months [7 pts.] or partial response by RECIST criteria [3 pts.]) rate was 26.3% (95%CI: 13.4-43.1%). cfDNA was obtained from 36 pts and mutations were identified in 13 (36%) including ESR1 [ Y537N or D538G] (5), PIK3CA [ H1047R or E542K] (8), TP53 [ K132R, R248Q, R267Q, or H179Y] (4), AKT ( Q79K) (1), and KRAS ( G12D) (1). In 5 pts with cf ESR1 mutations, 4 had additional cfDNA mutations including PIK3CA (3), and TP53 (1). PFS was shorter in pts with cfDNA mutations relative to those without (median: 61 vs.132 days; log-rank p = 0.021). Discordance was observed between tumor and cfDNA mutations where 3/7 PIK3CA tumor mutations were detected by cfDNA, 1/2 TP53 tumor mutations were detected by cfDNA, and 0/1 AKT tumor mutations were detected by cfDNA. Conversely, 2 pts had cfDNA mutations (either ESR1, TP53 or AKT) undetected in tumor. Conclusions: The absence of cfDNA mutations in patients with endocrine resistant, MBC treated with Z-Endoxifen was associated with significantly longer PFS. Given the discordance between tumor and cfDNA sequence data, future studies must determine which approach maximizes prognosis and prediction of benefit for estrogen-targeted therapy. Clinical trial information: NCT01327781.

A phase I study of cilengitide and paclitaxel in patients with advanced solid tumors

PURPOSE

Cilengitide is a potent and selective inhibitor of the integrins αvβ3 and αvβ5. The primary objective of this phase I clinical trial was to establish the maximum tolerated dose and determine safety/tolerability of cilengitide in combination with paclitaxel in patients with advanced solid tumors. Secondary objectives included the evaluation of the preliminary clinical outcomes.

PATIENTS AND METHODS

Patients with advanced solid tumors experiencing disease progression on standard treatment were assigned to two different dose levels of cilengitide (2000 mg intravenously once or twice weekly) in combination with fixed-dose, weekly paclitaxel (90 mg/m² intravenously).

RESULTS

Twelve evaluable patients were treated per protocol. A single dose limiting toxicity (DLT) of grade 4 neutropenia was observed at the starting dose level of once weekly cilengitide. There were no grade ≥3 adverse events that occurred with >10% frequency. One patient achieved a partial response to therapy. Five patients experienced stable disease as best response, 3 of which discontinued study participation due to progressive, peripheral neuropathy.

CONCLUSIONS

Cilengitide in combination with paclitaxel was well tolerated. Antitumor activity was observed. The recommended phase II dose is twice weekly cilengitide (2000 mg) with weekly paclitaxel (90 mg/m²). Further studies evaluating drugs that target this pathway are warranted.

Abstract PD2-03: Final results of a first-in-human phase I study of the tamoxifen (TAM) metabolite, Z-Endoxifen hydrochloride (Z-Endx) in women with aromatase inhibitor (AI) refractory metastatic breast cancer (MBC) (NCT01327781)

Background: AI's are more effective than TAM in ER+ breast cancer. In AI refractory MBC, the response rate to TAM is 0% (Osborne 2011). Z-Endx is an active metabolite of TAM and among TAM treated women in the adjuvant and metastatic settings, reduced CYP2D6 metabolism and low Endx concentrations (Css &lt;20 nM) have been associated with increased likelihood of disease recurrence. Preclinical studies have demonstrated greater Z-Endx exposure and anti-tumor activity with oral Z-Endx compared to equivalent doses of oral TAM (Reid 2014)

Methods: We conducted a phase I trial to determine the maximum-tolerated dose (MTD) and evaluate the toxicities, clinical activity, and pharmacokinetics (PK) of Z-Endx in patients (pts) with ER+, AI refractory MBC. Unlimited prior endocrine regimens were allowed. An accelerated titration schedule was applied (2 pts/dose level) until moderate toxicity or DLT, followed by a 3+3 design and then to expansion cohorts (40, 80, and 100 mg/day). Z-Endx was administered orally once daily (28 day cycle). Eye exams were performed at baseline, and end of cycles 2 and 6. PK was performed during cycle 1 and prior to subsequent cycles. For pts in the expansion cohorts, tumor biopsies were obtained at baseline for DNA sequencing (Foundation Medicine). Plasma cholesterol levels were obtained at baseline and after 1 cycle.

Results: From March 2011 to Dec 2014, 41 pts (38 evaluable), median age 60, received Z-Endx once daily encompassing 7 dose levels (20-160 mg/daily). The median number of prior hormonal regimens was 2 and 3 for the dose escalation and expansion cohorts, respectively. Dose escalation was stopped at 160 mg/day given MTD not reached and attainment of mean Endx Css of 3.6 uM. Cycle 1 DLT (PE) was observed in one patient (60 mg). No eye toxicity was observed. PK demonstrated mean Endx Css of &gt; 1 uM at all dose levels ≥ 40 mg/day. Antitumor activity was observed at multiple dose levels including 3 confirmed partial responses and an additional 7 with stable disease for ≥6 cycles. Of these 10 pts, 9 had prior progression on both AI and fulvestrant and 3 additionally on TAM. After 1 cycle, total and LDL cholesterol decreased &gt; 20 points in 54% and 40% of pts, respectively. Tumor sequencing in the expansion cohorts (n=14) did not identify ESR1 mutations; however, ESR1 amplification was identified in 1 pt with prolonged stable disease (&gt;200 days). Of 6 pts with rapid progression (≤2 cycles), 4/6 had either CCND1 amplification (n=1) or at least one of the following activating mutations: ERBB2 L755S (n=1), AKT1 E17K (n=1), MTOR E1799K (n=1).

Conclusions: The direct administration of Z-END provides substantial drug exposure, acceptable toxicity, and "proof of principle" antitumor activity in endocrine resistant MBC. While the MTD was not determined, the goal of achieving Endx Css concentrations of &gt; 1 uM was achieved. Tumor sequencing identified pts with predicted and confirmed endocrine resistance. A randomized phase II comparing endoxifen (80 mg/day) with TAM in AI refractory MBC was recently activated (NCT02311933). Supported in part by CA 133049, CA186686, CA15083, CA116201, and CA15083.

Citation Format: Goetz MP, Suman VJ, Reid JM, Northfelt DW, Mahr MA, Dockter T, Kuffel M, Buhrow SA, Safgren SL, McGovern RM, Collins JM, Streicher H, Hawse JR, Haddad TC, Erlichman C, Ames MM, Ingle JN. Final results of a first-in-human phase I study of the tamoxifen (TAM) metabolite, Z-Endoxifen hydrochloride (Z-Endx) in women with aromatase inhibitor (AI) refractory metastatic breast cancer (MBC) (NCT01327781). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr PD2-03.

Abstract P5-13-04: A phase II neoadjuvant trial of MK-2206, an AKT inhibitor, in combination with anastrozole for clinical stage 2 or 3 PIK3CA mutant estrogen receptor positive HER2 negative (ER+HER2-) breast cancer (BC)

Background

Activating mutations in PIK3CA occur in approximately 40% ER+BC. MK-2206 (M), a pan-AKT inhibitor, induced apoptosis of ER+ BC under estrogen deprivation in preclinical studies. We conducted this neoadjuvant trial to determine the pathologic complete response (pCR) rate of M plus anastrozole (A) for PIK3CA mutant (Mut) ER+ BC.

Methods

This single arm open label study of M+A used a 2-stage Simon phase II design (stage 1, n=16; stage 2, n=13, alpha=0.10, power=0.90) to test whether pCR rate &lt;1% (based on historical data with A alone), against the alternative that pCR rate ≥15% in PIK3CA Mut ER+ BC. At least 1 pCR in stage 1 was required to proceed to stage 2.

Eligible patients (pts) with clinical stage II or III ER+HER2- BC were pre-registered and proceeded to a research tumor biopsy for PIK3CA sequencing, followed by treatment with daily A monotherapy for 28 days (cycle 0). Pts with PIK3CA Mut BC were subsequently registered, underwent a second biopsy, and started M (150mg PO weekly) with daily A on cycle 1 day 1 (C1D1) for a maximum of four 28-day cycles followed by surgery. Goserelin was added for premenopausal pts. A tumor biopsy on C1D17, 17 days post the start of M, was performed. Those with C1D17 Ki67 &gt;10% discontinued study treatment. pCR was defined as no invasive cancer in the breast and the lymph nodes. Tumor specimens collected at all timepoints are being analyzed for markers of proliferation, apoptosis, and PI3K pathway activity, gene expression microarray, intrinsic subtypes, and next generation sequencing of 83 genes.

Results

Of the 51 pts pre-registered, 35 pts did not register due to no PIK3CA mutation (n=22), inadequate specimen for testing (n=6), physician/pt decision (n=7). The remaining 16 pts (median age: 58, range: 40-77 years) received combination therapy. Three pts did not complete 4 cycles due to C1D17 Ki67 &gt;10% (n=2) and intolerability (grade (Gr) 4 transaminase elevation in C1, n=1). Other severe toxicities possibly related to M included Gr 3 rash (25%) and pruritus (12.5%). Of the 13 pts completed study therapy and underwent surgery, all had residual disease in the breast and 7 also had positive nodes. Table 1 summarized changes in Ki67 during treatment.

ComparisonsnAbsolute changes in Ki67 median (range)Wilcoxon signed rank p-valueC1D1 relative to pre-registration11-17.0% (-49.8 to 4.1%)0.0020C1D17 relative to pre-registration14-16.4% (-51.4 to 4.1%)0.0004C1D17 relative to C1D112-1.5% (-18.6 to 15.8%)0.9697C1D1, biopsy post 28 days of A alone; C1D17 biopsy post 17 days on combination therapy

Although Ki67 levels post A monotherapy (C1D1) or M+A (C1D17) were significantly lower than that of pre-registration samples, Ki67 did not differ between C1D17 and C1D1 samples. Other correlative studies are ongoing and results will be presented.

Conclusion

Despite the small sample size, biomarker analysis on serial biopsy specimens demonstrated that M+A is unlikely to be more effective than A alone in PIK3CA Mut ER+ BC. This trial demonstrated the feasibility of genomic sequencing for pt selection and the value of a small, well-designed proof-of-principle neoadjuvant trial for the evaluation of targeted agents.

Citation Format: Ma CX, Suman VJ, Goetz M, Northfelt D, Burkard M, Ademuyiwa F, Naughton M, Margenthaler J, Aft R, Gray R, Tavaarwerk A, Wilke L, Haddad T, Moynihan T, Loprinzi C, Hieken T, Hoog J, Guo Z, Han J, Vij K, Mardis E, Sanati S, Al-Kateb H, Doyle L, Erlichman C, Ellis MJ. A phase II neoadjuvant trial of MK-2206, an AKT inhibitor, in combination with anastrozole for clinical stage 2 or 3 PIK3CA mutant estrogen receptor positive HER2 negative (ER+HER2-) breast cancer (BC). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-13-04.

Does the dose of leucovorin (LV) matter with 5-fluorouracil (5FU) in colorectal cancer (CRC)?

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Background: In June 2015 Cancer Care Ontario convened an expert panel to determine if there is an optimum LV dose in 5FU-LV combinations for the treatment of CRC. This request arose out of observed variation in LV dosages between some cancer centers. The research question was effect of LV dose on overall survival (OS), progression free survival (PFS), disease free survival (DFS), response rate (RR) and adverse events/toxicity, given a constant dose of 5FU. Methods: A systematic search was conducted for guidelines (GL) and comparative trials; eligibility included English language, with > 30 patients, that examined different doses of LV where dose of 5FU was not varied. Assessment of studies for inclusion was completed by 4 reviewers. Results: We identified 5 GL, 0 systematic reviews and 12 trials that defined a LV dose in combination with 5FU. None of the GL informed an optimal dose of LV. RR was assessed in 10 trials; 4 showed trends to higher RR with higher LV dose, but differences were not statistically significant (SS) between arms. PFS or DFS was reported in 6 trials and was similar between arms. Time to recurrence reported in one trial that included bevacizumab (BV) was longer in the high dose LV group that was SS. OS was addressed in 10 studies: no difference found in 7 studies; in one RCT OS was longer with the higher dose LV 55 vs. 45 months (p not reported); in one retrospective study OS was 23 vs. 20 months in favor of high dose LV (p not reported); one study of LV and BV had longer OS vs. lower dose LV at 26 vs. 21 months (SS). Toxicity: higher dose LV was associated with greater toxicity in 3 of 4 studies that reported stomatis, and increased rates of diarrhea in 9 of 11 trials. Meta-analysis was not appropriate as studies were too heterogeneous. Conclusions: There is no convincing evidence to identify an optimum dose of LV to be used in 5-FU/LV combinations. Amongst studies that did show a difference the trend was improved survival in favor of the higher dose. Similarly, differences in toxicities when identified were consistently greater with the higher dose LV. The expert panel concludes that the existing literature provides insufficient data to suggest that chemotherapy protocols should deviate from standard protocol doses.

A Phase I Study of the AKT Inhibitor MK-2206 in Combination with Hormonal Therapy in Postmenopausal Women with Estrogen Receptor-Positive Metastatic Breast Cancer

PURPOSE

PI3K/AKT pathway activation is an important endocrine resistance mechanism in estrogen receptor-positive (ER(+)) breast cancer. After promising preclinical modeling of MK-2206, an allosteric pan-AKT inhibitor, with either estrogen deprivation or fulvestrant, we conducted a phase I trial in patients with metastatic ER(+)HER2(-) breast cancer to determine the recommended phase II treatment dose (RPTD) of MK-2206 when combined with either anastrozole, fulvestrant, or anastrozole/fulvestrant.

EXPERIMENTAL DESIGN

ER(+) breast cancer cell lines were exposed in vitro to MK-2206 plus estrogen deprivation with or without fulvestrant and monitored for apoptosis. A standard 3+3 design was employed to first determine the maximum tolerated dose (MTD) of MK-2206 plus anastrozole based on cycle 1 toxicity. Each cycle was 28 days. The RPTD was determined on the basis of toxicities observed at MTD level during the first 3 cycles. Subsequent patients received MK-2206, at the RPTD determined above, plus fulvestrant or anastrozole/fulvestrant to define RPTD for these additional regimens.

RESULTS

MK-2206 induced apoptosis in parental ER(+) but not in long-term estrogen-deprived cell lines, for which fulvestrant was required for apoptosis induction. Thirty-one patients enrolled. The RPTD was defined as MK-2206 150 mg orally weekly with prednisone prophylaxis for each combination. Grade 3 rash was dose limiting. 42% (95% CI, 23%-63%) patients derived clinical benefit without progression within 6 months. Response was not associated with tumor PIK3CA mutation.

CONCLUSIONS

MK-2206 plus endocrine treatments were tolerable. MK-2206 in combination with anastrozole is being further evaluated in a phase II neoadjuvant trial for newly diagnosed ER(+)HER2(-) breast cancer. Clin Cancer Res; 22(11); 2650-8. ©2016 AACRSee related commentary by Jansen et al., p. 2599.

Abstract B113: Phase I and pharmacokinetic study of ixabepilone and temsirolimus in adult patients with advanced solid tumors

Background: The combination of a microtubule stabilizing agent and an mTOR inhibitor has been identified as a synergistic combination in preclinical models. Additional studies have further evaluated the impact of treatment sequence with paclitaxel and rapamycin where administration of rapamycin after paclitaxel was associated with synergy. In our preclinical studies, apoptosis was greater with the combination of ixabepilone and temsirolimus than with either single agent. Thus, a Phase I study of the combination of Ixabepilone (IXB) and Temsirolimus (TEM) was performed to determine the maximum tolerated dose (MTD), describe the toxicity profile and characterize the pharmacokinetics of each agent in patients with advanced cancer.

Methods: Eligible patients included adults with a histologically confirmed solid tumor malignancy that was metastatic or unresectable who have received ≤ 2 chemotherapy regimens and had ECOG PS ≤ 2 with adequate bone marrow, renal and hepatic function. Using a standard 3+3 design, patients were treated with IXB IV over 3 hours on day 1 and TEM IV over 0.5 hours on days 2 and 9 (schedule A) or days 1 and 8 (schedule B) every 21 days. Pharmacokinetics (PK) was performed in patients on schedule B.

Results: 22 evaluable patients were enrolled between August 24, 2011 and November 7, 2014. The final 7 patients were treated on schedule B. Patients were treated at 3 dose levels of IXB (mg/m2)/TEM (mg): DL1- 24/15 (A- 6 pts, B- 2 pts); DL2- 32/15 (A- 3 pts, B- 5 pts); DL3- 32/20 (A- 6 pts). One patient had DLT (grade 3 hypophosphatemia) and 1 patient expired due to disease progression in DL1A. No DLTs were seen in DL2A. The dose was escalated to DL3 and 1 patient had DLT (grade 3 hypokalemia). Following a change to schedule B, 5 patients were enrolled to DL2B and 1 experienced DLT (grade 4 neutropenia, grade 4 thrombocytopenia, grade 4 sepsis). The dose was reduced to DL1B and 2 more patients were enrolled, both of whom experienced DLTs (grade 5 bronchopulmonary hemorrhage and grade 4 neutropenia). Grade 4 events considered at least possibly related to treatment occurred in 6 of 22 patients (27%) and included cardiac arrest, dyspnea, hypokalemia, hypoxia, multi-organ failure, decreased platelets, acute renal failure, neutropenia, neutropenic fever, sepsis, and decreased WBCs. Patients received a median of 4 cycles (range, 1-10+). Partial response was noted in 1 patient and stable disease was noted in 11 patients. One patient remains on treatment after 11 cycles. IXB (plasma), TEM (whole blood) and sirolimus (whole blood) concentrations were measured by a sensitive, specific lc/ms/ms assay. A 24 and 32 mg/m2 IXB dose yields Cmax of 159 and 312 ng/ml, respectively. The IXB CLp and t1/2 values were 31 L/h and 76 h, respectively. The Cmax, Cl and t1/2 values after a 15 mg TEM dose were 518 ng/ml, 6.4 L/h and 11 h, respectively. The Cmax and t1/2 values of sirolimus after a 15 mg TEM dose were 37.6 ng/ml and 49 h, respectively. The PK of IXB and TEM in combination were similar to those reported for each drug alone.

Conclusions: The reasons for the unpredictable, severe toxicity of the IXB/TEM combination are unclear. The MTD could not be determined, and enrollment was discontinued. This trial exemplifies challenges associated with development of drug combinations with mTOR inhibitors.

Supported in part by UM1 CA186686 and P30 CA15083. Clinical trial information: NCT01375829

Citation Format: Joel M. Reid, Michael E. Menefee, Felix Boakye-Agyeman, Chad A. Walden, Charles Erlichman, Keith C. Bible. Phase I and pharmacokinetic study of ixabepilone and temsirolimus in adult patients with advanced solid tumors. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B113.

Phase I trial of FOLFIRI in combination with sorafenib and bevacizumab in patients with advanced gastrointestinal malignancies

BACKGROUND

A previous phase II trial in patients with chemorefractory metastatic colorectal cancer demonstrated a 63 % disease control rate with a combination of bevacizumab and sorafenib. This phase I trial sought to determine the maximum tolerable dose (MTD) of bevacizumab and sorafenib combined with standard cytotoxic therapy for advanced gastrointestinal (GI) cancers.

METHODS

A standard 3 + 3 trial design utilized 3 escalating sorafenib dose levels: (1) 200 mg daily, days 3-7, 10-14; (2) 200 mg twice daily, days 3-6, 10-13; and (3) 200 mg twice daily, days 3-7, 10-14 combined with standard dose FOLFIRI (5-fluouracil, leucovorin, and irinotecan) and bevacizumab (5 mg/kg), repeated every 14 days.

RESULTS

Fifteen patients were evaluable for safety and response assessment. There were no dose limiting toxicities (DLTs) at dose level 1 or 2. At dose level 3, two patients experienced DLTs (asymptomatic grade 3 hypophosphatemia, grade 3 dehydration and diarrhea). The MTD was determined to be dose level 2: sorafenib 200 mg twice daily, days 3-6, 10-13 combined with FOLFIRI and bevacizumab at standard doses. Four patients had a partial response and 8 had stable disease as best response (disease control rate of 80 %). Three patients with CRC had disease control >12 months.

CONCLUSIONS

The MTD of this regimen is sorafenib 200 mg twice daily, days 3-6, 10-13 combined with standard doses of FOLFIRI and bevacizumab. Dual antiangiogenic treatment combined with cytotoxic therapy may provide prolonged disease stabilization for select patients with advanced GI malignancies.

A First-in-Human Phase I Study of the Oral p38 MAPK Inhibitor, Ralimetinib (LY2228820 Dimesylate), in Patients with Advanced Cancer

PURPOSE

p38 MAPK regulates the production of cytokines in the tumor microenvironment and enables cancer cells to survive despite oncogenic stress, radiotherapy, chemotherapy, and targeted therapies. Ralimetinib (LY2228820 dimesylate) is a selective small-molecule inhibitor of p38 MAPK. This phase I study aimed to evaluate the safety and tolerability of ralimetinib, as a single agent and in combination with tamoxifen, when administered orally to patients with advanced cancer.

EXPERIMENTAL DESIGN

The study design consisted of a dose-escalation phase performed in a 3+3 design (Part A; n = 54), two dose-confirmation phases [Part B at 420 mg (n = 18) and Part C at 300 mg (n = 8)], and a tumor-specific expansion phase in combination with tamoxifen for women with hormone receptor-positive metastatic breast cancer refractory to aromatase inhibitors (Part D; n = 9). Ralimetinib was administered orally every 12 hours on days 1 to 14 of a 28-day cycle.

RESULTS

Eighty-nine patients received ralimetinib at 11 dose levels (10, 20, 40, 65, 90, 120, 160, 200, 300, 420, and 560 mg). Plasma exposure of ralimetinib (Cmax and AUC) increased in a dose-dependent manner. After a single dose, ralimetinib inhibited p38 MAPK-induced phosphorylation of MAPKAP-K2 in peripheral blood mononuclear cells. The most common adverse events, possibly drug-related, included rash, fatigue, nausea, constipation, pruritus, and vomiting. The recommended phase II dose was 300 mg every 12 hours as monotherapy or in combination with tamoxifen. Although no patients achieved a complete response or partial response,19 patients (21.3%) achieved stable disease with a median duration of 3.7 months, with 9 of these patients on study for ≥ 6 cycles.

CONCLUSIONS

Ralimetinib demonstrated acceptable safety, tolerability, and pharmacokinetics for patients with advanced cancer.

Gene expression profiling identifies responsive patients with cancer of unknown primary treated with carboplatin, paclitaxel, and everolimus: NCCTG N0871 (alliance)

BACKGROUND

Carboplatin (C) and paclitaxel (P) are standard treatments for carcinoma of unknown primary (CUP). Everolimus, an mTOR inhibitor, exhibits activity in diverse cancer types. We did a phase II trial combining everolimus with CP for CUP. We also evaluated whether a gene expression profiling (GEP) test that predicts tissue of origin (TOO) could identify responsive patients.

PATIENTS AND METHODS

A tumor biopsy was required for central confirmation of CUP and GEP. Patients with metastatic, untreated CUP received everolimus (30 mg weekly) with P (200 mg/m(2)) and C (area under the curve 6) every 3 weeks. The primary end point was response rate (RR), with 22% needed for success. The GEP test categorized patients into two groups: those having a TOO where CP is versus is not considered standard therapy.

RESULTS

Of 45 assessable patients, the RR was 36% (95% confidence interval 22% to 51%), which met criteria for success. Grade ≥3 toxicities were predominantly hematologic (80%). Adequate tissue for GEP was available in 38 patients and predicted 10 different TOOs. Patients with a TOO where platinum/taxane is a standard (n = 19) tended to have higher RR (53% versus 26%) and significantly longer PFS (6.4 versus 3.5 months) and OS (17.8 versus 8.3 months, P = 0.005), compared with patients (n = 19) with a TOO where platinum/taxane is not standard.

CONCLUSIONS

Everolimus combined with CP demonstrated promising antitumor activity and an acceptable side-effect profile. A tumor biomarker identifying TOO may be useful to select CUP patients for specific antitumor regimens.

CLINICALTRIALSGOV

NCT00936702.

Abstract B02: The Akt inhibitor MK-2206 in combination with rituximab and bendamustine demonstrates efficacy in relapsed/refractory chronic lymphocytic leukemia: Updated results from the NCCTG N1087 Alliance study

Background: PI3K/Akt activation is downstream of the B cell receptor (BCR) signaling cascade and is critical to mediate the interactions between CLL B-cell and bone marrow stroma which support leukemic survival. MK-2206 is a potent oral allosteric Akt inhibitor and we have demonstrated in vitro synergism with bendamustine (B) to induce CLL apoptosis. MK-2206 selectively abolishes BCR-stimulated cytokines CCL3, CCL4, CCL2, and IL-2Ra and significantly inhibits the BCR signaling pathway (Ding, BJH, 2013). We sought to assess the safety, maximal tolerated dose (MTD) and efficacy of MK-2206 in combination with B-rituximab (BR) in relapsed and refractory CLL/SLL patients in a phase I/II trial (NCCTG N1087 Alliance).

Methods: Previously treated symptomatic CLL/SLL patients with up to 3 prior lines of therapy and ECOG performance status of 0-2 were eligible. Patients with 17p deletion or prior treatment with B were excluded. A standard phase I design was used to determine the MTD of MK-2206 in combination with BR (B 70mg/m2 for 2 days per cycle; R cycle 1: 375 mg/m2, cycle 2-6: 500 mg/m2). Phase II employed the MTD to evaluate safety and efficacy of the combination. Response was evaluated 2 months after the last cycle of therapy per IWCLL 2008 criteria.

Results: 13 patients with a median age of 68 years (range 44-75) and 1.2 prior lines of therapy were treated. CLL FISH showed: del(11q) in 4 (31%), trisomy 12 in 2 (15%), del(13q) in 3 (23%), del(6q) (8%), del(17cen) (8%) and normal results in 2 (15%). IGHV was unmutated in 10 (91%) and mutated in 1 patient (9%) and was missing in 2 cases. ZAP-70 was positive in 8 (73%) and negative in 3 patients (27%). CD38 was positive in 8 (62%) and negative in 5 patients (38%). 70% of patients had received prior chemoimmunotherapy. At 90 mg of MK-2206, 1/6 patients experienced a DLT of grade 3 febrile neutropenia and hemolysis. 2/6 patients on the 135 mg dose experienced a DLT. One patient had grade 3 febrile neutropenia and one patient had a grade 3 acneiform rash. MTD was determined to be MK-2206 90 mg. The most common grade 3/4 adverse events were neutropenia (46%) including febrile neutropenia (23%), diarrhea (15%) and thrombocytopenia (15%). The most common all-grade toxicities were neutropenia (69%), thrombocytopenia (62%), anemia (54%), nausea (54%), diarrhea (39%), rash (38%), and hyperglycemia (31%).

10 patients were treated at 90 mg and 3 patients were treated at the 135 mg dose. The ORR was 92% (n=12). Responses were: 3 CR (23%), 2 CR with incomplete marrow recovery (CRi) (15%), 1 clinical CR (CCR) (8%) without marrow confirmation, 1 nodular partial remission (nPR) (8%), 5 PR (38%), and 1 progressive disease (8%). Median follow-up was 20 months (6-31 months). Median PFS in the CR/CRi group was not reached (NR) with 100% of patients progression free versus 12 months (95% CI 2 months-NR) if CR/CRi was not achieved (p=0.027). Median overall survival was NR in either the CR/CRi or non-CR/CRi groups but 2 deaths occurred in the latter group (p=0.44). One patient developed Richter transformation and died at 15 months and a second patient who had achieved PR died from autoimmune hemolytic anemia and fungal infection at 27 months. Two out of five patients who achieved CR or CRi had bone marrow MRD negative status at the final response evaluation.

Conclusions: The Akt inhibitor MK-2206 administered at 90 mg once weekly in combination with BR is tolerated in patients with relapsed or refractory CLL and compares favorably to BR alone (59% ORR and 9% CR, Fischer, JCO, 2011). An ORR of 92% was observed with a 38% of patients achieving CR or CRi. The trial was terminated prematurely due to withdrawal of sponsor support, however further testing of Akt inhibition is needed given the promising results.

Citation Format: Jeremy T. Larsen, Tait D. Shanafelt, Jose F. Leis, Betsy R. LaPlant, Timothy G. Call, Clive S. Zent, Curtis A. Hanson, Charles Erlichman, Thomas M. Habermann, Craig B. Reeder, Deborah A. Bowen, Michael Conte, Justin C. Boysen, Charla R. Secreto, Connie E. Lesnick, Renee C. Tschumper, Diane F. Jelinek, Neil E. Kay, Wei Ding. The Akt inhibitor MK-2206 in combination with rituximab and bendamustine demonstrates efficacy in relapsed/refractory chronic lymphocytic leukemia: Updated results from the NCCTG N1087 Alliance study. [abstract]. In: Proceedings of the AACR Special Conference: Targeting the PI3K-mTOR Network in Cancer; Sep 14-17, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(7 Suppl):Abstract nr B02.

Phase II trial of gemcitabine and tanespimycin (17AAG) in metastatic pancreatic cancer: a Mayo Clinic Phase II Consortium study

OBJECTIVES

Heat Shock Protein 90 (HSP90) is a molecular chaperone that stabilizes many oncogenic proteins. HSP90 inhibitors may sensitize tumors to cytotoxic agents by causing client protein degradation. Gemcitabine, which has modest activity in pancreas cancer, activates Chk1, a client protein of HSP90. This phase II trial was designed to determine whether 17AAG could enhance the clinical activity of gemcitabine through degradation of Chk1 in patients with stage IV pancreatic cancer.

METHODS

A multicenter, prospective study combining gemcitabine and 17AAG enrolled patients with stage IV pancreatic adenocarcinoma, adequate liver and kidney function, ECOG performance status 0-2, and no prior chemotherapy for metastatic disease. The primary goal was to achieve a 60 % overall survival at 6 months. Sixty-six patients were planned for accrual, with an interim analysis after 25 patients enrolled.

RESULTS

After a futility analysis to achieve the endpoint, accrual was halted with 21 patients enrolled. No complete or partial responses were seen. Forty percent of patients were alive at 6 months. Median overall survival was 5.4 months. Tolerability was moderate, with 65 % of patients having ≥ grade 3 adverse events (AE), and 15 % having grade 4 events.

CONCLUSIONS

The lack of clinical activity suggests that targeting Chk1 by inhibiting HSP90 is not important in pancreatic cancer sensitivity to gemcitabine alone. Further studies of HSP90 targeted agents with gemcitabine alone are not warranted.

Safety and activity of temsirolimus and bevacizumab in patients with advanced renal cell carcinoma previously treated with tyrosine kinase inhibitors: a phase 2 consortium study

PURPOSE

Bevacizumab or temsirolimus regimens have clinical activity in the first-line treatment of advanced renal cell carcinoma (RCC). This phase I/II trial was conducted to determine the safety of combining both agents and its efficacy in RCC patients who progressed on at least one prior anti-VEGF receptor tyrosine kinase inhibitor (RTKI) agent.

METHODS

In the phase I portion, eligible patients were treated with temsirolimus (25 mg IV weekly) and escalating doses of IV bevacizumab (level 1 = 5 mg/kg; level 2 = 10 mg/kg) every other week. The primary endpoint for the phase II portion (RTKI resistant patients) was the 6-month progression-free rate. Secondary endpoints were response rate, toxicity evaluation, and PFS and OS.

RESULTS

Maximum tolerated dose was not reached at the maximum dose administered in 12 phase I patients. Forty evaluable patients were treated with the phase II recommended dose (temsirolimus 25 mg IV weekly and bevacizumab 10 mg/kg IV every 2 weeks). The 6-month progression-free rate was 40 % (16/40 pts). Median PFS was 5.9 (4-7.8) months, and median OS was 20.6 (11.5-23.7) months. Partial response, stable disease, and progressive disease were seen in 23, 63, and 14 % of patients, respectively. Most common grade 3-4 AEs included fatigue (17.8 %), hypertriglyceridemia (11.1 %), stomatitis (8.9 %), proteinuria (8.9 %), abdominal pain (6.7 %), and anemia (6.7 %). Baseline levels of serum sFLT-1 and VEGF-A were inversely correlated with PFS and OS, respectively.

CONCLUSIONS

Temsirolimus and bevacizumab is a feasible combination in patients with advanced RCC previously exposed to oral anti-VEGF agents. The safety and efficacy results warrant further confirmatory studies in this patient population.

Multicenter Phase II Trial of Temsirolimus and Bevacizumab in Pancreatic Neuroendocrine Tumors

PURPOSE

There are few effective therapies for pancreatic neuroendocrine tumors (PNETs). Recent placebo-controlled phase III trials of the mammalian target of rapamycin (mTOR) inhibitor everolimus and the vascular endothelial growth factor (VEGF)/platelet-derived growth factor receptor inhibitor sunitinib have noted improved progression-free survival (PFS). Preclinical studies have suggested enhanced antitumor effects with combined mTOR and VEGF pathway-targeted therapy. We conducted a clinical trial to evaluate combination therapy against these targets in PNETs.

PATIENTS AND METHODS

We conducted a two-stage single-arm phase II trial of the mTOR inhibitor temsirolimus 25 mg intravenously (IV) once per week and the VEGF-A monoclonal antibody bevacizumab 10 mg/kg IV once every 2 weeks in patients with well or moderately differentiated PNETs and progressive disease by RECIST within 7 months of study entry. Coprimary end points were tumor response rate and 6-month PFS.

RESULTS

A total of 58 patients were enrolled, and 56 patients were eligible for response assessment. Confirmed response rate (RR) was 41% (23 of 56 patients). PFS at 6 months was 79% (44 of 56). Median PFS was 13.2 months (95% CI, 11.2 to 16.6). Median overall survival was 34 months (95% CI, 27.1 to not reached). For evaluable patients, the most common grade 3 to 4 adverse events attributed to therapy were hypertension (21%), fatigue (16%), lymphopenia (14%), and hyperglycemia (14%).

CONCLUSION

The combination of temsirolimus and bevacizumab had substantial activity and reasonable tolerability in a multicenter phase II trial, with RR of 41%, well in excess of single targeted agents in patients with progressive PNETs. Six-month PFS was a notable 79% in a population of patients with disease progression by RECIST criteria within 7 months of study entry. On the basis of this trial, continued evaluation of combination mTOR and VEGF pathway inhibitors is warranted.

A phase II study of AZD2171 (cediranib) in the treatment of patients with acute myeloid leukemia or high-risk myelodysplastic syndrome

Patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) not fit for intensive treatment need novel therapy options. Vascular endothelial growth factor (VEGF) receptor inhibition is one potential mechanism by which AML and MDS could be treated. The receptor tyrosine kinase inhibitor AZD2171 (cediranib) has activity against VEGF receptors KDR and FLT-1. This multicenter phase II study was designed to test cediranib's activity in patients with AML or high-risk MDS. The primary endpoint was confirmed disease response defined as a composite of complete remission, partial remission or hematologic improvement. The study enrolled 23 subjects in the AML cohort and 16 subjects in the MDS cohort. There were no confirmed responses in either group. Since the study met the stopping rule after the first stage of enrollment, the trial was closed to further accrual. Common adverse events in both cohorts included thrombocytopenia, neutropenia, anemia, fatigue, dyspnea, diarrhea, nausea and dehydration.

A multicenter phase 2 trial of pazopanib in metastatic and progressive medullary thyroid carcinoma: MC057H

CONTEXT

Pazopanib is a small molecule inhibitor of kinases principally including vascular endothelial growth factor receptors-1, -2, and -3; platelet-derived growth factor receptors-α and -β; and c-Kit. We previously reported a tumor response rate of 49% in patients with advanced differentiated thyroid cancer and 0% in patients with advanced anaplastic thyroid cancer. The present report details results of pazopanib therapy in advanced medullary thyroid cancer (MTC). OBJECTIVE, DESIGN, SETTING, PATIENTS, INTERVENTION, AND OUTCOME MEASURES: Having noted preclinical activity of pazopanib in MTC, patients with advanced MTC who had disease progression within the preceding 6 months were accrued to this multiinstitutional phase II clinical trial to assess tumor response rate (by Response Evaluation Criteria In Solid Tumors criteria) and safety of pazopanib given orally once daily at 800 mg until disease progression or intolerability.

RESULTS

From September 22, 2008, to December 11, 2011, 35 individuals (80% males, median age 60 y) were enrolled. All patients have been followed up until treatment discontinuation or for a minimum of four cycles. Eight patients (23%) are still on the study treatment. The median number of therapy cycles was eight. Five patients attained partial Response Evaluation Criteria In Solid Tumors responses (14.3%; 90% confidence interval 5.8%-27.7%), with a median progression-free survival and overall survival of 9.4 and 19.9 months, respectively. Side effects included treatment-requiring (new) hypertension (33%), fatigue (14%), diarrhea (9%), and abnormal liver tests (6%); 3 of 35 patients (8.6%) discontinued therapy due to adverse events. There was one death of a study patient after withdrawal from the trial deemed potentially treatment related.

CONCLUSIONS

Pazopanib has promising clinical activity in metastatic MTC with overall manageable toxicities.

Context-dependent antagonism between Akt inhibitors and topoisomerase poisons

Signaling through the phosphatidylinositol-3 kinase (PI3K)/Akt pathway, which is aberrantly activated in >50% of carcinomas, inhibits apoptosis and contributes to drug resistance. Accordingly, several Akt inhibitors are currently undergoing preclinical or early clinical testing. To examine the effect of Akt inhibition on the activity of multiple widely used classes of antineoplastic agents, human cancer cell lines were treated with the Akt inhibitor A-443654 [(2S)-1-(1H-indol-3-yl)-3-[5-(3-methyl-2H-indazol-5-yl)pyridin-3-yl]oxypropan-2-amine; ATP-competitive] or MK-2206 (8-[4-(1-aminocyclobutyl)phenyl]-9-phenyl-2H-[1,2,4]triazolo[3,4-f][1,6]naphthyridin-3-one;dihydrochloride; allosteric inhibitor) or with small interfering RNA (siRNA) targeting phosphoinositide-dependent kinase 1 (PDK1) along with cisplatin, melphalan, camptothecin, or etoposide and assayed for colony formation. Surprisingly different results were observed when Akt inhibitors were combined with different drugs. Synergistic effects were observed in multiple cell lines independent of PI3K pathway status when A-443654 or MK-2206 was combined with the DNA cross-linking agents cisplatin or melphalan. In contrast, effects of the Akt inhibitors in combination with camptothecin or etoposide were more complicated. In HCT116 and DLD1 cells, which harbor activating PI3KCA mutations, A-443654 over a broad concentration range enhanced the effects of camptothecin or etoposide. In contrast, in cell lines lacking activating PI3KCA mutations, partial inhibition of Akt signaling synergized with camptothecin or etoposide, but higher A-443654 or MK-2206 concentrations (>80% inhibition of Akt signaling) or PDK1 siRNA antagonized the topoisomerase poisons by diminishing DNA synthesis, a process that contributes to effective DNA damage and killing by these agents. These results indicate that the effects of combining inhibitors of the PI3K/Akt pathway with certain classes of chemotherapeutic agents might be more complicated than previously recognized.

Phase I trial of FOLFIRI in combination with sorafenib and bevacizumab in patients with advanced gastrointestinal malignancies

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Background: Sorafenib inhibits various pro-angiogenesis pathways including PDGFR-B, a factor associated with resistance to anti-VEGF therapy. A previous phase II trial in patients with chemorefractory metastatic CRC demonstrated a 63% disease control rate with a combination of bevacizumab (BEV) and sorafenib. This phase I trial sought to determine the MTD of BEV and sorafenib combined with standard cytotoxic therapy for advanced gastrointestinal (GI) cancers. Methods: Patients with advanced GI malignancies appropriate for irinotecan-based therapy were enrolled (14 with CRC, 3 gastroesophageal). A standard 3 + 3 design was used with 3 escalating sorafenib dose levels (DL): (1) 200 mg po daily, days 3-7, 10-14; (2) 200 mg po twice daily, days 3-6, 10-13; and (3) 200 mg po twice daily, days 3-7, 10-14. FOLFIRI: irinotecan 180 mg/m2 d1, leucovorin 400 mg/m2 d1, 5-fluorouracil (FU) bolus 400 mg/m2 d1, 5-FU infusion 2400 mg/m2d1-2 and BEV 5 mg/kg d1. 1 cycle = 14 days. Results: Seventeen pts were enrolled, median age of 56 (range 32 and 81). Two pts were replaced, as they did not complete DLT evaluation, leaving 15 evaluable pts. Four evaluable pts at DL1 and 6 pts at DL2 had no DLTs. At DL 3, the first cohort of 3 pts did not experience any DLTs. In the second cohort of 3 pts, 2 pts experienced DLTs (asymptomatic G3 hypophosphatemia, G3 dehydration and diarrhea). MTD was determined to be DL2: sorafenib 200 mg PO twice daily, days 3-6, 10-13 combined with FOLFIRI and BEV at standard doses. Of the 15 evaluable pts, 4 pts had PR, 8 pts had SD as best response, 1 pt had PD, and 2 pts discontinued treatment prior to first tumor assessment. The median number of cycles was 10 (range 1-37). Three pts with CRC had disease control > 12 months. Conclusions: The MTD of this regimen is sorafenib 200 mg PO twice daily, days 3-6,10-13 combined with standard doses of FOLFIRI and BEV. Dual VEGF inhibition combined with cytotoxic therapy may provide prolonged disease stabilization for select patients with advanced GI malignancies. Supported by CA69912 and CA15083. Clinical trial information: NCT01383343.

Abstract B273: Multicenter Phase II study of MK-2206 in previously treated patients (pts) with recurrent and metastatic nasopharyngeal carcinoma (NPC): Mayo Clinic Phase II Consortium (Protocol: MC1079)

Background: NPC is endemic to Asia and over 40% of cases harbor PIK3CA amplification. MK2206 is an allosteric AKT inhibitor with activity in NPC in vitro.

Methods: Pts who had progressed after palliative chemotherapy (chemo) for metastatic or recurrent NPC, received oral MK-2206 at 200 mg on Days 1, 8, 15 & 22 of each 28-day cycle until disease progression. Plasma samples were collected at serial time points during cycle 1 for EBV DNA analysis, archived tumor samples were collected where feasible. The primary dual endpoints (2-stage design) consisted of RECIST-defined tumor response rate (RR) and 6-month (m) progression-free survival (PFS) rate. Secondary endpoints were overall survival (OS), PFS and adverse events (AEs).

Results: Of the 21 pts enrolled, the median age was 47 years (range: 32-67), 91% were male, 81% had prior radiotherapy and 81% had &gt; 1 prior line of palliative chemo. At the time of analysis, 20 out of 21 pts have ended treatment. The best responses were: 1 partial response (PR, 5%) lasting 4 ms; 10 stable disease (SD, 50%), 9 progressive disease (PD, 45%). The 6-m PFS rate was 38.9% (95% CI: 18.1-59.3%) and median PFS was 2.7 ms (95% CI: 0.9-7.2 ms). The 6-m OS rate was 67.9% (95% CI: 41.8-84.1%) and median survival has not been reached. In 7 pts who had SD more than or equal to 6 ms, the duration of treatment ranged from 6.4-13.9 ms. Of the 21 pts evaluable for AEs, 12 pts (57%) had at least one grade 3 AE [[Unable to Display Character: &#8211;]] macular rash (6 pts - 29%), dysphagia (2 pts - 10%), hyperglycemia (2 pts - 10%) (see Table 1). The tumor samples of 7 pts were analyzed by FISH; 3 showed PIK3CA amplification, including 1 pt with chromosome 3 polysomy. Amongst these pts, 1 had SD more than 6ms, 1 had SD more than 12 ms, and 1 is still on treatment. Pts who had SD less than 6 m or PD did not have PIK3CA amplification.

Conclusions: MK2206 is well tolerated and has signs of activity in unselected pts with NPC. Preliminary results suggest that PIK3CA amplification may be related to prolonged disease stabilization from MK2206, and analysis for other PIK3CA gene alterations in more samples will be undertaken. Result of the plasma EBV DNA result will be presented.

Phase 1 study of sorafenib in combination with bortezomib in patients with advanced malignancies

BACKGROUND

Sorafenib (a VEGFR and multi-targeted kinase inhibitor) and Bortezomib (a proteasome inhibitor) have clinical antineoplastic activities as single agents, and combine synergistically in preclinical models.

METHODS

This Phase I study was undertaken to define the toxicity and the maximum tolerated doses (MTD) of the combination in patients with advanced solid tumors. Patients with cytologic or histologic proof of unresectable solid tumors were treated with escalating doses of sorafenib (twice daily) and bortezomib (days 1, 4, 8 and 11 intravenously) with 21-day cycles.

RESULTS

Fourteen patients (7 males, median age 65, range 24-74), with renal (3), lung (3), pancreas (2), and breast, adrenal gland, melanoma, spindle cell tumor, chronic lymphocytic leukemia and multiple myeloma (1 each) were enrolled. All patients are off treatment, 10 due to disease progression. DLT was seen in two patients (one grade 3 abdominal pain and grade 4 lipase elevation; one with grade 3 vomiting) at sorafenib 200 mg twice daily and bortezomib 1.3 mg/m(2), establishing the MTD. No grade 4 hematologic or grade 5 toxicities were seen. One patient with renal cell cancer had a partial response and 5 patients attained stable disease.

CONCLUSIONS

The combination of sorafenib and bortezomib was tolerated well. The recommended phase 2 doses are sorafenib 200 mg twice daily continuously with bortezomib 1 mg/m(2) on days 1, 4, 8, 11 (21 day cycles). The combination shows preliminary signs of efficacy, supporting phase 2 studies.

A multicenter phase II study of bevacizumab (B) and temsirolimus (T) in women with recurrent epithelial ovarian cancer (OC): A study of the Mayo, Chicago, California, New York, Southeast, and Princess Margaret Phase II Consortia

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Background: Anti-angiogenic therapy is active in OC; the combination of VEGF and mTOR inhibitors is hypothesized to further improve activity. This report is the OC cohort of a multi-histology phase II study assessing the activity and toxicity of B/T. Methods: Patients (Pts) with recurrent epithelial OC who had received ≤ 2 chemotherapy regimens and no prior treatment with a VEGF or mTOR inhibitor were eligible. A two-stage design was used with second stage accrual if >6 pts had objective responses (OR) or >10 pts of the first 25 remained progression-free (PF) at six months (mo). Pre-defined end-points for a recommendation for further clinical trial evaluation included at least 15/50 with OR or 26/50 PF at six mo. Treatment included T 25 mg IV wkly and B 10 mg/kg IV q14 days on 28 day cycles. Results: 58 pts were enrolled (the first 50 pts are used to determine a final recommendation). Median age=62 (range 35-82). A median of 4 (range 1-23) cycles were administered. 24 were platinum-sensitive, 34 resistant. Off-study reasons included 13 adverse events and disease progression in 38. 3 refused further therapy due to toxicity. 14 of the first 50 pts had partial response (PR) (9 platinum-resistant); 25/50 remained PF (8 PR, 15 SD, 2 non-progressing) at 6 mo. Grade (gr) 3/4 toxicities occurring >2 events include: fatigue (4), stomatitis (7), hypertension (5), neutropenia (4), thrombocytopenia (4), hypokalemia (3). One rectal and one vaginal fistula, and two colonic perforations (one gr 2 and one gr 3 during cycles 3 and 1 respectively) were observed. Episodes of gr 1/2 oral, nasal, pulmonary, vaginal and gastrointestinal hemorrhage were also observed. Conclusions: Although the OR and PFS did not reach pre-defined standards, the numbers of OR and 6 mo PFS suggest potential enhanced activity with a combination of mTOR inhibitor with anti-angiogenic therapy. Other combinations of these targeted agents may result in more satisfactory activity with less toxicity. N01-CM-62203 (PMH) N01-CM-62208 (Southeast Phase 2) N01 CM-62209 (CCCP) N01-CM-62204 (NYCC) N01-CM-2011-0071C (Chicago) N01-CM62205 (Mayo) Clinical trial information: NCT01010126.

Multicenter phase II trial of temsirolimus (TEM) and bevacizumab (BEV) in pancreatic neuroendocrine tumor (PNET)

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Background: PNET has long had few effective therapies other than chemotherapy. Placebo-controlled phase III trials of the mTOR inhibitor everolimus and the VEGF/PDGF receptor inhibitor sunitinib noted improved progression-free survival (PFS). However, objective response rates (RR) with these agents are still <10%. Preclinical studies suggest enhanced anti-tumor effects with combined mTOR and VEGF targeted therapy. Methods: We conducted a phase II trial of the mTOR inhibitor TEM (25 mg IV q week) and the VEGF-A monoclonal antibody BEV (10 mg/kg IV q 2 weeks) in patients (pts) with well or moderately differentiated PNET and progressive disease by RECIST within 7 months of study entry. Co primary endpoints were RR and 6-month PFS. Planned enrollment was 50 patients, with interim analysis for futility after the first 25 evaluable pts. Pts had no prior mTOR or VEGF targeted agents, ECOG PS 0-1, and adequate hematologic and organ function. Continued octreotide was allowed, but not required. Prior interferon, embolization, and ≤ 2 chemotherapy regimens were allowed. Results: 55 pts were eligible for response assessment. Confirmed PR was documented in 20 of 55 patients (37%). 44 of 55 (80%) patients were progression-free at 6 months. Of 49 pts evaluable for this endpoint, 12 month PFS is 49%. 15 patients remain on therapy. For evaluable patients, the most common grade 3-4 adverse events attributed to therapy were hypertension (18%), hyperglycemia (13%), fatigue (11%). leukopenia (9%), headache (9%), proteinuria (7%), and hypokalemia (7%). Conclusions: The combination of TEM/BEV has substantial activity in a multi-center phase II trial with RR of 37%, well in excess of single targeted agents in PNET. 6-month PFS was a notable 80% in a population of patients with RECIST criteria progression within 7 months of study entry. Phase III trials of combined VEGF/mTOR inhibition in PNET should be pursued. Clinical trial information: NCT01010126.

A phase II study of combination epigenetic therapy in metastatic colorectal cancer (mCRC): A phase II consortium (P2C)/Stand Up 2 Cancer (SU2C) study

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Background: Therapy with decitabine and entinostat (ENT: HDAC inhibitor) shows synergistic effect in re-expression of tumor-suppressor genes and growth inhibition in CRC cell lines and in vivo studies. Methods: We conducted a phase II, multi-institutional study of SQ 5-azacitidine (AZA) and oral ENT in mCRC pts. A 28 day cycle included: AZA at 40 mg/m2 d1-5 and 8-10 with ENT 7 mg d3 and 10. Initial eligibility criteria included: ECOG PS 0-1, good end organ function, and biopsiable disease for cohort A (CoA). An interim analysis indicated that toxicity which crossed pre-specified safety boundary was secondary to disease. A 2nd cohort B (CoB) with eligibility restrictions: <2 prior regimens in KRAS-mutated CRC pts, <3 prior regimens if KRAS wild-type, and liver disease limited to <30% of volume was accrued. Serial tumor biopsies and research blood were collected to assess for methylation/expression changes in circulating tumor DNA and biopsies, respectively. The primary endpoint was response as measured by RECIST criteria using a 2-stage Simon design. Results: 47 pts were initially enrolled (24 CoA, 23 CoB). Pts received a median of 2 cycles on both cohorts (1-16 CoA, 2-6 CoB). Pts had a median of 4 prior therapies for CoA (range 2-9) and 3 for CoB (range 2-6). Gr 4 AEs attributable to treatment for CoA included hyperglycemia (1) and hypokalemia (1); other common Gr 3 AEs included anemia (3), decreased lymphocytes (7), fatigue (3), and nausea (3). CoB pts experienced grade 3 chest pain (1), neutropenia (2), leucopenia (2), urinary tract obstruction (1), and hypophosphatemia (1). No responses have been observed. Results of translational objectives will be presented at the meeting. Conclusions: SQ AZA and ENT therapy does not have clinical activity as defined by confirmed response in aCRC. Follow-up for survival, response to subsequent therapy, and correlative analysis are ongoing. Supported in part by N01-CM-2011-00099. Clinical trial information: NCT01105377. [Table: see text]

A pilot study of the patient-reported outcomes version of the common terminology criteria for adverse events (PRO-CTCAE) in a phase I clinical trial

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Background: Recently the Patient-Reported Outcomes version of the CTCAE was developed to augment clinically graded adverse events with information reported directly by patients on clinical trials (Basch, 2009). The validation and potential application of PRO-CTCAE in phase I clinical trials are of great interest as toxicity is the primary endpoint. Methods: Selected PRO-CTCAE items (21 items measuring 12 symptomatic adverse events) corresponding to the major adverse events required to be graded clinically were collected in an ongoing phase I clinical trial of weekly cilengitide and paclitaxel in patients with advanced solid malignancies (NCT01276496). PRO-CTCAE was administered in a paper booklet by a clinical research associate prior to treatment on days 1, 8 and 15 of their regular visits. These PRO-CTCAE items were summarized descriptively in comparison to clinician-assessed CTCAE ver 4.0 (NCI, 2009) during the first cycle. As a pilot study to assess feasibility of PRO-CTCAE in phase I trials, PRO-CTCAE was not intended for determination of dose-limiting toxicity. Results: Twelve patients were accrued to two separate doses of cilengitide and paclitaxel. The median age was 56 (range 36—67) and half of patients were female. All patients had an ECOG performance score <= 1. Over 90% of patients had received prior surgery and chemotherapy. All but one patient completed weekly PRO-CTCAE during the first cycle, the only patient refused to complete weeks 2 and 3 did not give a reason. PRO-CTCAE captured most of the symptomatic adverse events reflected in clinician-assessed CTCAE. Some symptomatic adverse events were not reported clinically by CTCAE but were reported by patients by PRO-CTCAE. Overall, PRO-CTCAE items indicated slightly more severe degree of symptoms experienced by patients than those reported in CTCAE. Conclusions: This is the first study that PRO-CTCAE items were integrated within regular study visits in a phase I trial. The administration of PRO-CTCAE has been proved feasible and fruitful, providing consistent and enhanced symptomatic toxicity from the patient point of view. The addition of PRO-CTCAE did not significantly increase patient burden. Clinical trial information: NCT01276496.

Phase I dose escalation study of the protein kinase C iota inhibitor aurothiomalate for advanced non-small cell lung cancer, ovarian cancer, and pancreatic cancer

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Background: Protein kinase C iota (PKCi) is overexpressed in non-small cell lung (NSCLC), ovarian and pancreatic cancers and promotes tumorigenesis. The gold compound aurothiomalate (ATM) inhibits downstream activation of Rac1 by PKCi. We sought to determine the maximum tolerated dose (MTD) of ATM. Methods: We conducted a phase I dose escalation trial of ATM in patients with NSCLC, ovarian or pancreatic cancer. In the dose escalation cohort patients received ATM IM weekly for three cycles (cycle duration 4 weeks) at 25 mg, 50 mg or 75 mg in a 3+3 design. The dose was not escalated for individual patients. Up to 9 subjects were allowed to enroll in the expansion cohort at the MTD. Blood samples were analyzed for elemental gold levels. Patients were evaluated for response every eight weeks with computed tomography using modified response evaluation criteria in solid tumors. Results: Fifteen patients, all pretreated, enrolled in this study. There were ten patients with NSCLC, four with ovarian cancer and one with pancreatic cancer. Six patients were treated at the 25 mg dose, 6 patients at 50 mg, and 2 at 75 mg. There was 1 dose limiting toxicity (DLT) at 25 mg (hypokalemia), 1 DLT at 50 mg (urinary tract infection), and none at 75 mg. There were 3 grade 3 hematologic toxicities in the dose escalation cohort. The recommended MTD of ATM is 50 mg, and 1 subject was treated in the expansion cohort at 50 mg. Patients received treatment for a median of 2 cycles (range 1-3). The best response observed was stable disease in 2 subjects. There appeared to be a dose-related accumulation of steady-state plasma concentrations of gold with concentrations exceeding 20 µM after one month of therapy with 75 mg of ATM and after 2 months of therapy with 50 mg of ATM, consistent with linear pharmacokinetics. Conclusions: In summary, this phase I study was successful in identifying ATM 50 mg IM weekly as the MTD. In this heavily pre-treated group of patients in who we observed at best stable disease, it remains unclear whether future investigations that target PKCi should focus on single agent ATM, combination therapy with ATM, or other PKCi inhibitors that are currently in development. Clinical trial information: NCT00575393.