Use of gene expression profiling to identify responsive patients treated with carboplatin (Carb), paclitaxel (Pac), and everolimus as first-line treatment for cancer of unknown primary (CUP): NCCTG N0871 (Alliance)

2562

Background: Empiric chemotherapy (taxane/platinum) is standard for CUP. Because prognosis is poor, novel approaches are needed. The PI3K/mTOR pathway is frequently dysregulated in cancer. Everolimus (E), an mTOR inhibitor, is approved for multiple malignancies. We performed a phase II study of Pac + Carb + E as first-line therapy in metastatic CUP patients (pts). We additionally determined if a gene expression profiling (GEP) test that identifies tissue of origin (Pathwork Tissue of Origin) could identify responsive pts. (NCT00936702) Methods: Newly diagnosed, untreated CUP pts were eligible. Central pathology review confirmed CUP prior to registration; GEP was performed on formalin fixed tumor tissue. Pac (200 mg/m2), Carb (AUC=6) and E (30 mg once weekly) were delivered every 3 wks until progression or intolerable adverse events (AEs). The primary endpoint was confirmed response, with ≥11 of 50 responses (22%) needed for trial success. Secondary endpoints were OS, progression-free survival (PFS) and AEs. Results: 46 pts (median age 61) received a median 4 cycles (range: 1-33). 39 (85%), 21 (46%) and 1 (2%) experienced ≥1 grade (gr) 3+, 4+, or 5 (sepsis) AE, with gr 3+ hematologic AE most common (74%). Of 44 evaluable pts, 15 had a confirmed response (RR 34%, 95% CI: 21-50%), with a median PFS and OS of 4.1 and 10.1 mos, respectively. Adequate tissue for GEP was available in 36 pts and predicted 10 different sites of origin. In pts with a predicted tissue of origin in which taxane/platinum is standardly used, higher RR and significantly longer PFS and OS were observed compared with pts whose GEP identified a malignancy where taxane/platinum is not standard (Table). Conclusions: In pts with untreated CUP, Carb +Pac +E demonstrated promising antitumor activity. The GEP test identified patients clinically responsive to Carb/Pac/E therapy, and may be useful to select CUP pts for specific antitumor regimens. Clinical trial information: NCT00936702. [Table: see text]

A phase I trial of the IGF-1R antibody Cixutumumab in combination with temsirolimus in patients with metastatic breast cancer

The mammalian target of rapamycin (mTOR) plays a critical role in promoting tumor cell growth and is frequently activated in breast cancer. In preclinical studies, the antitumor activity of mTOR inhibitors is attenuated by feedback up-regulation of AKT mediated in part by Insulin-like growth factor type 1 receptor (IGF-1R). We designed a phase I trial to determine the maximum-tolerated dose (MTD) and pharmacodynamic effects of the IGF-1R antibody Cixutumumab in combination with temsirolimus in patients with metastatic breast cancer refractory to standard therapies. A 3 + 3 Phase I design was chosen. Temsirolimus and Cixutumumab were administered intravenously on days 1, 8, 15, and 22 of a 4-week cycle. Of the 26 patients enrolled, four did not complete cycle 1 because of disease progression (n = 3) or comorbid condition (n = 1) and were replaced. The MTD was determined from the remaining 22 patients, aged 34-72 (median 48) years. Most patients (86 %) had estrogen receptor positive cancer. The median number of prior chemotherapy regimens for metastatic disease was 3. The MTD was determined to be Cixutumumab 4 mg/kg and temsirolimus 15 mg weekly. Dose-limiting toxicities (DLTs) included mucositis, neutropenia, and thrombocytopenia. Other adverse events included grade 1/2 fatigue, anemia, and hyperglycemia. No objective responses were observed, but four patients experienced stable disease that lasted for at least 4 months. Compared with baseline, there was a significant increase in the serum levels of IGF-1 (p < 0.001) and IGFBP-3 (p = 0.019) on day 2. Compared with day 2, there were significant increases in the serum levels of IGF-1 (p < 0.001), IGF-2 (p = 0.001), and IGFBP-3 (p = 0.019) on day 8. A phase II study in women with metastatic breast cancer is ongoing.

Open-label, dose-escalation, safety, pharmacokinetic, and pharmacodynamic study of intravenously administered CNF1010 (17-(allylamino)-17-demethoxygeldanamycin [17-AAG]) in patients with solid tumors

BACKGROUND

17-(Allylamino)-17-demethoxygeldanamycin (17-AAG) is a benzoquinone ansamycin that binds to and inhibits the Hsp90 family of molecular chaperones leading to the proteasomal degradation of client proteins critical in malignant cell proliferation and survival. We have undertaken a Phase 1 trial of CNF1010, an oil-in-water nanoemulsion of 17-AAG.

METHODS

Patients with advanced solid tumors and adequate organ functions received CNF1010 by 1-h intravenous (IV) infusion, twice a week, 3 out of 4 weeks. Doses were escalated sequentially in single-patient (6 and 12 mg/m(2)/day) and three-to-six-patient (≥25 mg/m(2)/day) cohorts according to a modified Fibonacci's schema. Plasma pharmacokinetic (PK) profiles and biomarkers, including Hsp70 in PBMCs, HER-2 extracellular domain, and IGFBP2 in plasma, were performed.

RESULTS

Thirty-five patients were treated at doses ranging from 6 to 225 mg/m(2). A total of 10 DLTs in nine patients (2 events of fatigue, 83 and 175 mg/m(2); shock, abdominal pain, ALT increased, increased transaminases, and pain in extremity at 175 mg/m(2); extremity pain, atrial fibrillation, and metabolic encephalopathy at 225 mg/m(2)) were noted. The PK profile of 17-AAG after the first dose appeared to be linear up to 175 mg/m(2), with a dose-proportional increase in C max and AUC0-inf. Hsp70 induction in PBMCs and inhibition of serum HER-2 neu extracellular domain indicated biological effects of CNF1010 at doses >83 mg/m(2).

CONCLUSION

The maximum tolerated dose was not formally established. Hsp70 induction in PBMCs and inhibition of serum HER-2 neu extracellular domain indicated biological effects. The CNF1010 clinical program is no longer being pursued due to the toxicity profile of the drug and the development of second-generation Hsp90 molecules.

Phase I study of tanespimycin in combination with bortezomib in patients with advanced solid malignancies

PURPOSE

To determine the maximum tolerated dose (MTD) and characterize the dose-limiting toxicities (DLT) of tanespimycin when given in combination with bortezomib.

EXPERIMENTAL DESIGN

Phase I dose-escalating trial using a standard cohort "3+3" design performed in patients with advanced solid tumors. Patients were given tanespimycin and bortezomib twice weekly for 2 weeks in a 3 week cycle (days 1, 4, 8, 11 every 21 days).

RESULTS

Seventeen patients were enrolled in this study, fifteen were evaluable for toxicity, and nine patients were evaluable for tumor response. The MTD was 250 mg/m(2) of tanespimycin and 1.0 mg/m(2) of bortezomib when used in combination. DLTs of abdominal pain (13 %), complete atrioventricular block (7 %), fatigue (7 %), encephalopathy (7 %), anorexia (7 %), hyponatremia (7 %), hypoxia (7 %), and acidosis (7 %) were observed. There were no objective responses. One patient had stable disease.

CONCLUSIONS

The recommended phase II dose for twice weekly 17-AAG and PS341 are 250 mg/m(2) and 1.0 mg/m(2), respectively, on days 1, 4, 8 and 11 of a 21 day cycle.

Phase II consortium (P2C) study of gemcitabine and tanespimycin (17AAG) for metastatic pancreatic cancer

245

Background: Gemcitabine (GEM) monotherapy for PDA has modest activity. 17-N-Allylamino-17-demthoxygeldanamycin (Tanespimycin/17AAG), is an HSP90 inhibitor, which results in degradation of a number of client proteins such as RAF and Akt. Arlander et al (J Biol Chem. 2003 278:52572-7) have demonstrated that 17AAG targeting of HSP90 leads to Chk1 degradation. Chk1 is upregulated with GEM treatment which affects cell survival (Karnitz et al. Mol Pharmacol. 2005 68:1636-44). In vitro, the combination demonstrated in vitro synergy. Thus the potential clinical activity in pancreatic cancer of the combination was explored. Methods: A phase II multicenter prospective study was performed using GEM 750 mg/m2 d1,8 and 17AAG 154 mg/m2 d2,9 on a 21 day cycle, as defined in a previous phase I trial. Patients with stage IV PDA, with adequate liver, kidney function and counts, ECOG 0-2 and no prior therapy for metastatic disease were eligible. The primary endpoint of 60% overall survival at 6 months was considered of clinical interest. Sixty-six patients were planned for accrual, and an interim analysis was planned after 25 evaluable patients. Informed, written consent was obtained from all pts. Results: Due to lack of drug availability and failure to achieve the planned endpoint, accrual was halted at 21 pts, enrolled from 5/08 to 9/10, of which 20 were evaluable (1 cancelled prior to treatment). Median age was 61.5 yrs., 55% were male, PS 0 (50%), 1 (45%), 2 (5%); 95% were non-Hispanic white, 1 was African American. Two had received adjuvant therapy for PDA. Tolerability was moderate, with 13 pts (65%) having > grade 3 adverse event (AE), with 15% gr 4 AEs and 0% gr 5. Nausea (20%), vomiting (20%), constipation (15%), dehydration (15%), and anorexia (10%), were the most common non-heme AEs. Lymphopenia (15%), leukopenia (10%) and neutropenia (10%) were common grade 3 hematologic AEs. No complete or partial responses were seen. 40% of patients were alive at 6 months, with a median OS of 5.4 months. Conclusions: HSP 90 inhibitor 17AAG in combination with GEM does not show activity for treatment of PDA. Further trials should not be pursued with this combination. Supported by N01-CM-62205. Clinical trial information: NCT00577889.

The clinical case for proton beam therapy

Over the past 20 years, several proton beam treatment programs have been implemented throughout the United States. Increasingly, the number of new programs under development is growing. Proton beam therapy has the potential for improving tumor control and survival through dose escalation. It also has potential for reducing harm to normal organs through dose reduction. However, proton beam therapy is more costly than conventional x-ray therapy. This increased cost may be offset by improved function, improved quality of life, and reduced costs related to treating the late effects of therapy. Clinical research opportunities are abundant to determine which patients will gain the most benefit from proton beam therapy. We review the clinical case for proton beam therapy. SUMMARY SENTENCE: Proton beam therapy is a technically advanced and promising form of radiation therapy.

Development of a multidisciplinary, multicampus subspecialty practice in endocrine cancers

PURPOSE

Relative to more abundant neoplasms, endocrine cancers have been historically neglected, yet their incidence is increasing. We therefore sought to build interest in endocrine cancers, improve physician experience, and develop innovative approaches to treating patients with these neoplasms.

METHODS

Between 2005 and 2010, we developed a multidisciplinary Endocrine Malignancies Disease Oriented Group involving all three Mayo Clinic campuses (Rochester, MN; Jacksonville, FL; and Scottsdale, AZ). In response to higher demand at the Rochester campus, we sought to develop a Subspecialty Tumor Group and an Endocrine Malignancies Tumor Clinic within the Division of Medical Oncology.

RESULTS

The intended groups were successfully formed. We experienced difficulty in integration of the Mayo Scottsdale campus resulting from local uncertainty as to whether patient volumes would be sufficient to sustain the effort at that campus and difficulty in developing enthusiasm among clinicians otherwise engaged in a busy clinical practice. But these obstacles were ultimately overcome. In addition, with respect to the newly formed medical oncology subspecialty endocrine malignancies group, appointment volumes quadrupled within the first year and increased seven times within two years. The number of active therapeutic endocrine malignancies clinical trials also increased from one in 2005 to five in 2009, with all three Mayo campuses participating.

CONCLUSION

The development of subspecialty tumor groups for uncommon malignancies represents an effective approach to building experience, increasing patient volumes and referrals, and fostering development of increased therapeutic options and clinical trials for patients afflicted with otherwise historically neglected cancers.

A multiinstitutional phase 2 trial of pazopanib monotherapy in advanced anaplastic thyroid cancer

CONTEXT/OBJECTIVES

Pazopanib, an inhibitor of kinases including vascular endothelial growth factor receptor, demonstrated impressive activity in progressive metastatic differentiated thyroid cancer, prompting its evaluation in anaplastic thyroid cancer (ATC).

DESIGN/SETTING/PATIENTS/INTERVENTIONS/OUTCOME MEASURES

Preclinical studies, followed by a multicenter single arm phase 2 trial of continuously administered 800 mg pazopanib daily by mouth (designed to provide 90% chance of detecting a response rate of >20% at the 0.10 significance level when the true response rate is >5%), were undertaken. The primary trial end point was Response Evaluation Criteria in Solid Tumors (RECIST) response.

RESULTS

Pazopanib displayed activity in the KTC2 ATC xenograft model, prompting clinical evaluation. Sixteen trial patients were enrolled; 15 were treated: 66.7% were female, median age was 66 yr (range 45-77 yr), and 11 of 15 had progressed through prior systemic therapy. Enrollment was halted, triggered by a stopping rule requiring more than one confirmed RECIST response among the first 14 of 33 potential patients. Four patients required one to two dose reductions; severe toxicities (National Cancer Institute Common Toxicity Criteria-Adverse Events version 3.0 grades >3) were hypertension (13%) and pharyngolaryngeal pain (13%). Treatment was discontinued because of the following: disease progression (12 patients), death due to a possibly treatment-related tumor hemorrhage (one patient), and intolerability (radiation recall tracheitis and uncontrolled hypertension, one patient each). Although transient disease regression was observed in several patients, there were no confirmed RECIST responses. Median time to progression was 62 d; median survival time was 111 d. Two patients are alive with disease 9.9 and 35 months after the registration; 13 died of disease.

CONCLUSIONS

Despite preclinical in vivo activity in ATC, pazopanib has minimal single-agent clinical activity in advanced ATC.

Epigenetic therapy using belinostat for patients with unresectable hepatocellular carcinoma: a multicenter phase I/II study with biomarker and pharmacokinetic analysis of tumors from patients in the Mayo Phase II Consortium and the Cancer Therapeutics Research Group

PURPOSE

Epigenetic aberrations have been reported in hepatocellular carcinoma (HCC). In this study of patients with unresectable HCC and chronic liver disease, epigenetic therapy with the histone deacetylase inhibitor belinostat was assessed. The objectives were to determine dose-limiting toxicity and maximum-tolerated dose (MTD), to assess pharmacokinetics in phase I, and to assess activity of and explore potential biomarkers for response in phase II.

PATIENTS AND METHODS

Major eligibility criteria included histologically confirmed unresectable HCC, European Cooperative Oncology Group performance score ≤ 2, and adequate organ function. Phase I consisted of 18 patients; belinostat was given intravenously once per day on days 1 to 5 every 3 weeks; dose levels were 600 mg/m(2) per day (level 1), 900 mg/m(2) per day (level 2), 1,200 mg/m(2) per day (level 3), and 1,400 mg/m(2) per day (level 4). Phase II consisted of 42 patients. The primary end point was progression-free survival (PFS), and the main secondary end points were response according to Response Evaluation Criteria in Solid Tumors (RECIST) and overall survival (OS). Exploratory analysis was conducted on pretreatment tumor tissues to determine whether HR23B expression is a potential biomarker for response.

RESULTS

Belinostat pharmacokinetics were linear from 600 to 1,400 mg/m(2) without significant accumulation. The MTD was not reached at the maximum dose administered. Dose level 4 was used in phase II. The median number of cycles was two (range, one to 12). The partial response (PR) and stable disease (SD) rates were 2.4% and 45.2%, respectively. The median PFS and OS were 2.64 and 6.60 months, respectively. Exploratory analysis revealed that disease stabilization rate (complete response plus PR plus SD) in tumors having high and low HR23B histoscores were 58% and 14%, respectively (P = .036).

CONCLUSION

Epigenetic therapy with belinostat demonstrates tumor stabilization and is generally well-tolerated. HR23B expression was associated with disease stabilization.

Biomarker-driven trial in metastatic pancreas cancer: feasibility in a multicenter study of saracatinib, an oral Src inhibitor, in previously treated pancreatic cancer

Src tyrosine kinases are overexpressed in pancreatic cancers, and the oral Src inhibitor saracatinib has shown antitumor activity in preclinical models of pancreas cancer. We performed a CTEP-sponsored Phase II clinical trial of saracatinib in previously treated pancreas cancer patients, with a primary endpoint of 6-month survival. A Simon MinMax two-stage phase II design was used. Saracatinib (175 mg/day) was administered orally continuously in 28-day cycles. In the unselected portion of the study, 18 patients were evaluable. Only two (11%) patients survived for at least 6 months, and three 6-month survivors were required to move to second stage of study as originally designed. The study was amended as a biomarker-driven trial (leucine rich repeat containing protein 19 [LRRC19] > insulin-like growth factor-binding protein 2 [IGFBP2] "top scoring pairs" polymerase chain reaction [PCR] assay, and PIK3CA mutant) based on preclinical data in a human pancreas tumor explant model. In the biomarker study, archival tumor tissue or fresh tumor biopsies were tested. Biomarker-positive patients were eligible for the study. Only one patient was PIK3CA mutant in a 3' untranslated region (UTR) portion of the gene. This patient was enrolled in the study and failed to meet the 6-month survival endpoint. As the frequency of biomarker-positive patients was very low (<3%), the study was closed. Although we were unable to conclude whether enriching for a subset of second/third line pancreatic cancer patients treated with a Src inhibitor based on a biomarker would improve 6-month survival, we demonstrate that testing pancreatic tumor samples for a biomarker-driven, multicenter study in metastatic pancreas cancer is feasible.

Gemcitabine and irinotecan as first-line therapy for carcinoma of unknown primary: results of a multicenter phase II trial

Metastatic carcinoma of unknown primary (CUP) has a very poor prognosis, and no standard first-line therapy currently exists. Here, we report the results of a phase II study utilizing a combination of gemcitabine and irinotecan as first-line therapy. Treatment was with gemcitabine 1000 mg/m² and irinotecan 75 mg/m² weekly times four on a six week cycle (Cohort I). Due to excessive toxicity, the dose and schedule were modified as follows: gemcitabine 750 mg/m² and irinotecan 75 mg/m² given weekly times three on a four week cycle (Cohort II). The primary endpoint was the confirmed response rate (CR + PR). Secondary endpoints consisted of adverse events based upon the presence or absence of the UDP glucuronosyltransferase 1 family, polypeptide A1*28 (UGT1A1*28) polymorphism, time to progression, and overall survival. Thirty-one patients were enrolled with a median age of 63 (range: 38–94), and 26 patients were evaluable for efficacy. Significant toxicity was observed in Cohort 1, characterized by 50% (7/14) patients experiencing a grade 4+ adverse event, but not in cohort II. The confirmed response rate including patients from both cohorts was 12% (95% CI: 2–30%), which did not meet the criteria for continued enrollment. Overall median survival was 7.2 months (95% CI: 4.0 to 11.6) for the entire cohort but notably longer in cohort II than in cohort I (9.3 months (95% CI: 4.1 to 12.1) versus 4.0 months (95% CI: 2.2 to 15.6)). Gemcitabine and irinotecan is not an active combination when used as first line therapy in patients with metastatic carcinoma of unknown primary. Efforts into developing novel diagnostic and therapeutic approaches remain important for improving the outlook for this heterogeneous group of patients.

Phase 2 trial of daily, oral Polyphenon E in patients with asymptomatic, Rai stage 0 to II chronic lymphocytic leukemia

BACKGROUND

The objective of the current study was to follow up the results of phase 1 testing by evaluating the clinical efficacy of the green tea extract Polyphenon E for patients with early stage chronic lymphocytic leukemia (CLL).

METHODS

Previously untreated patients with asymptomatic, Rai stage 0 to II CLL and an absolute lymphocyte count (ALC) ≥ 10 × 10(9) /L were eligible for this phase 2 trial. Polyphenon E with a standardized dose of epigallocatechin gallate (EGCG) (2000 mg per dose) was administered twice daily.

RESULTS

A total of 42 patients received Polyphenon E at a dose of 2000 mg twice daily for up to 6 months. Of these patients, 29 (69%) had Rai stage I to II disease. Patients received a median of 6 cycles of treatment (range, 1 cycle-6 cycles). The most common grade 3 side effects (according to National Cancer Institute Common Terminology Criteria for Adverse Events) were transaminitis (1 patient), abdominal pain (1 patient), and fatigue (1 patient). Clinical activity was observed, with 13 patients (31%) experiencing a sustained reduction of ≥ 20% in the ALC and 20 of 29 patients (69%) with palpable adenopathy experiencing at least a 50% reduction in the sum of the products of all lymph node areas. EGCG plasma levels after 1 month of therapy were found to be correlated with reductions in lymphadenopathy (correlation co-efficient, 0.44; P = .02). Overall, 29 patients (69%) fulfilled the criteria for a biologic response with either a sustained decline ≥ 20% in the ALC and/or a reduction ≥ 30% in the sum of the products of all lymph node areas at some point during the 6 months of active treatment.

CONCLUSIONS

Daily oral EGCG in the Polyphenon E preparation was well tolerated by patients with CLL in this phase 2 trial. Durable declines in the ALC and/or lymphadenopathy were observed in the majority of patients.

A phase 2 trial of flavopiridol (Alvocidib) and cisplatin in platin-resistant ovarian and primary peritoneal carcinoma: MC0261

PURPOSE

Based upon promising preclinical and phase 1 trial results, combined flavopiridol and cisplatin therapy was evaluated in patients with ovarian and primary peritoneal cancers.

METHODS

A two cohort phase 2 trial of cisplatin (60 mg/m2 IV) immediately followed by flavopiridol (100 mg/m2 IV, 24 h infusion; 21 day cycles) was undertaken in patients with recurrent platin-sensitive or platin-resistant disease (progression>vs. ≤6 months following prior platin-based therapy). Measurable disease (RECIST)--or evaluable disease plus CA125>2X post-treatment nadir--and ECOG performance≤2 were required.

RESULTS

Forty-five patients were enrolled between December 23, 2004 and February 25, 2010: 40 platin-resistant (Group 1), and 5 platin-sensitive (Group 2). In Group 1, the median number of treatment cycles was 3 (range 2-12). Only 10% of patients incurred grade 4 toxicities, but grade 3 toxicities were common (65%): neutropenia (17.5%); nausea (12.5%); vomiting, fatigue, thrombosis, anemia (10% each). Seven patients (17.5%) achieved a confirmed response (1 CR, 6 PR; median duration 118 days); ten additional patients (25%) attained maintained stable disease. Median time to progression was 4.3 months; overall survival was 16.1 months. Pilot translational studies assessed ascites flavopiridol level; surrogate marker studies were uninformative. In Group 2, although 4 of 5 patients responded (2 confirmed PRs with median time to progression, 10.8 months and median overall survival 20.6 months) the cohort was closed due to poor accrual.

CONCLUSIONS

The assessed flavopiridol and cisplatin regimen displayed clinical activity in platin resistant and sensitive ovarian/primary peritoneal cancers, meriting further study.

A multi-institutional phase II trial of pazopanib monotherapy in advanced anaplastic thyroid cancer

5544

Background: Pazopanib, an orally bioavailable multitargeted inhibitor of kinases including VEGF-R, demonstrated impressive activity in metastatic differentiated thyroid cancer (49% durable RECIST PRs) and promising preclinical activity in anaplastic thyroid cancer (ATC) models, prompting its evaluation also as a candidate therapeutic in advanced ATC. Methods: A multicenter single arm phase II trial of 800 mg pazopanib daily was undertaken with the primary endpoint of RECIST response rate. The trial was designed such that there would be a 90% chance of detecting a response rate of >20% at the 0.10 significance level when the true tumor response rate is >5%. A pre-specified stopping rule designated that enrollment would cease unless 1 or more RECIST PRs+CRs were observed in the first 14 of 33 potential patients. Eligibility required informed consent, >18 years of age, performance status ECOG 0-2, systolic blood pressure (BP) <140 mm Hg and diastolic BP <90 mm Hg at entry, QTc interval <480 msecs, and measurable disease by RECIST criteria. Anatomical imaging and toxicity evaluations were required every 4 weeks. Results: Sixteen patients were enrolled. One patient withdrew prior to therapy, leaving 15 evaluable patients – 33.3% were male, with a median age of 66 years (range 45-77); 11 of 15 patients had progressed through prior systemic therapy. Four patients required 1-2 dose reductions, with the most common severe toxicities (CTC-AE version 3.0 grades 3-5) hypertension (13%) and pharyngolaryngeal pain (13%). Reasons for treatment discontinuation included: disease progression (12 pts), death on study due to a vascular event possibly related to treatment (1 pt.), and intolerability (radiation recall tracheitis – 1 pt, and uncontrolled hypertension – 1 pt). Although transient disease regression was observed in several patients, there were no confirmed RECIST tumor responses, triggering study closure at time of interim analysis. Two patients are alive with disease 9.9 months and 2.9 years post-registration; the remaining 13 died of disease. The median time to progression was 62 days and the median survival time was 111 days. Conclusions: Pazopanib has poor single agent activity in advanced anaplastic thyroid cancer.

A phase I trial of the IGF-1R antibody IMC-A12 in combination with temsirolimus in patients with metastatic breast cancer

534

Background: mTOR plays a critical role in promoting tumor cell growth. In preclinical studies, the anti-tumor activity of mTOR inhibitors is attenuated by feedback up-regulation of AKT mediated by IGF-1R. We designed a phase I trial to determine the maximum-tolerated dose (MTD), dose-limiting toxicities (DLT) and pharmacodynamic effects of the IGF-1R antibody IMC-A12 in combination with temsirolimus (tem) in patients (pts) with metastatic breast cancer (MBC) where mTOR is frequently activated. Methods: A 3+3 phase I design was chosen. Tem and IMC-A12 were administered IV days (d) 1, 8, 15, and 22 of a 4-week cycle in pts with MBC refractory to standard therapies. Tumor response was evaluated by RECIST. Adverse events (AE) were reported using CTC v3.0. Serum IGF 1 and C-peptide levels on d2 (24h post infusion) and d8 prior to drug infusion were compared to baseline (BL) using paired t-test. Results: Of 26 pts enrolled, 4 did not complete cycle 1 due to progression (3) or co-morbid condition (1). MTD was determined from remaining 22 pts aged 34-72 (median 48) years with ECOG PS 0 (55%) or 1 (45%). 86% had ER+ cancer. Median number of regimens for MBC was 4. Two DLTs at the starting DL (DL 1) necessitated dose de-escalation of tem to 20mg (DL-1), then to 15 mg (DL-2) which was tolerable (Table). Subsequent dose escalation of IMC-A12 led to DLTs in 0 of 6 in DL-2A and 2 of 3 pts in DL-2B. The MTD was defined as DL-2A. Other AEs included gr 1/2 fatigue, neutropenia, anemia, and hyperglycemia. No CR or PR, but 4 SD lasting ≥ 4 months were observed. At DL-2, -2A and -2B, serum IGF 1 levels were significantly elevated on d2 (p <0.002) and d8 compared to BL (p <0.001), but C-peptide levels were not found to differ from BL. Conclusions: The MTD for the combination of IMC-A12 and tem in pts with MBC is lower than that observed for single agents alone. A phase II study is ongoing in MBC. The study is supported in part by ASCO CDA, Komen Craft to CXM, N01-CM62205 and N01-CM-2011-00071. [Table: see text]

Multicenter phase II trial of temsirolimus (TEM) and bevacizumab (BEV) in pancreatic neuroendocrine tumor (PNET): Results of a planned interim efficacy analysis

4047

Background: PNET has long had few effective therapies other than chemotherapy. Recent 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 is 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: Confirmed PR was documented in 13 of the first 25 (52%) evaluable patients. 21 of 25 (84%) patients were progression-free at 6 months. Both endpoints exceeded the protocol-defined criteria to continue enrollment. For 36 evaluable patients, the most common grade 3-4 adverse events attributed to therapy were hypertension (14%), leukopenia (11%), lymphopenia (11%), hyperglycemia (11%), mucositis (8%), hypokalemia (8%), and fatigue (8%). Conclusions: The combination of TEM/BEV has substantial activity in a multi-center phase II trial with RR of 52%, well in excess of single targeted agents in PNET. 6-month PFS was a notable 84% in a population of patients with RECIST criteria progression within 7 months of study entry. Accrual is ongoing.

Phase I trial of everolimus, gemcitabine and cisplatin for patients with solid tumors refractory to standard therapy

e13052

Background: The combination of GEM and CDDP has shown activity in a variety of cancers, including biliary tract/gallbladder. Preclinical testing shows a potential benefit to the addition of EV. Methods: Using a standard 3+3 design, the MTDs of GEM + EV (Cohort I) and GEM + CDDP + EV (Cohort II) were determined as shown in the table. The MTD was defined as the dose level below the lowest dose that induces a DLT in at least one-third of pts. At the MTD of Cohort II, 10 patients were enrolled with biliary tract/gallbladder cancer (Cohort III). A weekly CBC was obtained. Assessments occurred every 3 weeks and imaging for response at every other cycle. Results: In Cohort I (N=12), no DLT occurred at dose level 0, and in dose level 1, grade 3 thrombocytopenia was found in 2 of 6 pts. The MTD for Cohort I was determined to be dose level 0. Responses were seen in 3 pts: 2 CRs (primary peritoneal, pancreatic) and 1 PR (breast). In Cohort II (N=15) DLTs at dose level 0 were neutropenia and thrombocytopenia in 2 of 3 pts and at dose level -1, thrombocytopenia in 2 of 6 pts. At dose level -2, 1 of 6 pts experienced a DLT (grade 3 thrombocytopenia), establishing this dose level as the MTD. Responses were seen in 2 pts, both PRs (ampullary, pheochromocytoma). All 10 pts have been enrolled in Cohort III with 2 DLTs (neutropenia and thrombocytopenia). Stable disease seen in 5 of 7 evaluable pts. Conclusions: Gem + EV was well tolerated at dose level 0, though dose escalation was limited by thrombocytopenia. GEM + CDDP + EV had DLTs of neutropenia and thrombocytopenia leading to the MTD of dose level of -2. Cohort III is fully accrued and the 2 DLTs are hematologic. [Table: see text]

Randomized trial of oral cyclophosphamide (C) with or without veliparib (V), an oral poly (ADP-ribose) polymerase (PARP) inhibitor, in patients with recurrent BRCA-positive ovarian, or primary peritoneal or high-grade serous ovarian carcinoma

5020

Background: V+C was well tolerated in a phase I trial and responses and prolonged disease stabilization were observed in BRCA + patients (pts).To assess the relative contribution of the PARP inhibitor to the efficacy observed for the combination, we conducted a randomized multicenter trial comparing the response rate (RR) of V and C to the RR of C alone in patients with deleterious BRCA mutations and recurrent ovarian, or primary peritoneal, fallopian tube or high-grade serous ovarian cancer. Methods: Pts were ≥ 18 yrs, KPS ≥ 70%, had adequate organ function, prior therapy with PARP inhibitors was allowed.Both drugs were administered orally qd; C 50 mg, V 60 mg; 21 day cycles. Pts were randomized to receive either C alone or V+C. At disease progression, pts on C alone were allowed to cross over to the combination. Radiologic imaging was performed at baseline and q 3 cycles for assessment of response. Dose reduction of V was allowed to 40 mg for gr 3 non-hematologic or gr 4 hematologic toxicities. The study design had an 88% power to detect the difference between a 15% RR for C alone versus 35% for V+C, early closure if fewer responses were observed on the combination arm in the first 65 pts enrolled (half of the total projected accrual). Results: Total of 74 pts were enrolled (36 pts C, 38 pts V+C), median age 58 (37-79 yrs), # of prior therapies: median 4 (1-9), 2 pts had prior PARP therapy. Treatment was well tolerated, Gr ≥ 2 toxicities per arm for initial regimen (# of pts): C alone: lymphopenia (2), mucositis (1); V+C: lymphopenia (4), anemia (2), leucopenia (2), neutropenia (2). Of the 74 pts evaluable for response at the interim analysis, 3 PRs observed in 36 pts on V+C and 5 PRs of 38 pts on C alone arm; thus accrual was stopped. PAR levels assessed by validated ELISA were inhibited (>80%) in PBMCs in 9/10 pts 4 hours post V, no inhibition with C alone. Conclusions: Addition of V, a PARP inhibitor, to C did not improve RR versus C alone. Exomic sequencing, gene expression studies, and Fanconi Anemia triple stain immunofluorescence (FATSI) assay for FancD2 nuclear foci formation using archival tissue are ongoing.

Phase II study of AZD2171 for the treatment of patients with myelodysplastic syndromes

6570

Background: Inhibition of vascular endothelial growth factor receptors (VEGFR) can block growth and trigger apoptosis in neoplastic cells. AZD2171 (cediranib) is a highly potent, orally bioavailable, VEGFR-1/2 inhibitor. We conducted a phase II study of the efficacy of AZD2171 for the treatment of MDS. Methods: Adults with MDS (IPSS Int-2 or High) were eligible if they exhibited adequate organ function and ECOG 0-2. The primary endpoint was proportion of responses according to the IWG criteria assessed at one and every 3 months. Prior investigation of cediranib at 45 mg daily in patients with acute leukemia demonstrated toxicity concerns and therefore, the starting dose of this study was lowered to 30 mg daily. Results: A total of 16 pts with MDS (median age 73 years) were enrolled at a 30 mg starting dose, and all were evaluable. Median baseline marrow blasts were 12.0 % (range 2-18); 3 pts (18.8 %) had low, 6 (37.5 %) intermediate, and 7 (43.8 %) had high risk cytogenetics. Prior therapy included azacitidine (n=7), decitabine (n=2), cytarabine (n=2), erythropoietin-stimulating agents (ESAs) (n=2), lenalidomide (n=1), or none (n=6). Patients were treated for a median of two 28-day cycles (range 1 to 11). There were no confirmed responses. Patients with baseline blasts > 5% showed no significant reduction in the blast count at 4 and 12 weeks. Median OS was 4.7 mo (95% CI: 2.6 – 11.6). Median TTP was 3.8 mo (95% CI: 1.7 – 10.8). Grade 4 hematological adverse events at least possibly related to cediranib were neutropenia (n=2) and thrombocytopenia (n=4). Grade 3 hematological adverse events at least possibly related to study treatment included: neutropenia (n=3), thrombocytopenia (n=2), and anemia (n=2). Grade 3 non-hematological adverse events included fatigue (n=4), dyspnea (n=3), dehydration (n=2), diarrhea (n=2), nausea (n=2), asthenia (n=1), and hypertension (n=1). Hypertension and proteinuria was uncommon with the 30 mg/day dose. Conclusions: With no confirmed response from 16 patients, cediranib was determined to be ineffective at a dose of 30 mg daily in our patient population. Supported by NCI N01-CM62205, NCI P30-CA014520 and the UW Carbone Comprehensive Cancer Center.

Phase II trial of temsirolimus and bevacizumab for initial recurrence of endometrial cancer

5025

Background: We report the interim results of the endometrial arm of a multi-tumor protocol using temsirolimus and bevacizumab in endometrial cancer (EMCA) patients at the time of their initial recurrence. The primary aim of this trial is to assess treatment efficacy in terms of both confirmed tumor response and 6-month progression free survival (PFS). Methods: Women with a performance status of 0 or 1 who have had their first recurrence for EMCA were eligible. Subjects who had chemotherapy as part of their adjuvant treatment after front line surgical staging were also eligible. The regimen included Temsirolimus 25 mg IV weekly followed by bevacizumab 10mg/kg IV on days 1 and 15 of a 28 day cycle. A modified two-stage Simon design with fixed sample size was adopted with the null hypothesis being that the true tumor response rate is at most 25% and the true 6 month PFS rate is at most 50%. Results: We enrolled 26 evaluable subjects to the first stage of which one did not proceed with treatment. The median age at enrollment was 60 (range 40-80). 22 (85%) were white and 19 (73%) were not Hispanic/Latino. 19 (73%) of subjects had prior raditation therapy, with 4 having a prior para-aortic boost. 5 (20%) subjects had a confirmed PR and 12 (48%) were progression-free at 6 months, which fell short of the futility stopping rule. An additional 5 (20%) subjects had a best response of confirmed SD, so 10 (40%) had overall clinical benefit from this regimen. AEs attributable to treatment were modest and included 16 grade 3 adverse events, of which the most common ones included hypertension, hyperglycemia, and neutropenia. There were 2 grade 4 events that were possibly treatment related including a duodenal perforation and an anorectal infection. Conclusions: While there was clinical benefit of this regimen in women at the time of their first recurrence of EMCA, the combination of temsirolimus and bevacizumab did not achieve our prespecified efficacy assumptions. This differs from what has been reported with this combination as a second line therapy for recurrent EMCA, where prespecified response assumptions differ. Also, the regimen had comparable safety and toxicity to other cytotoxic chemotherapy regimens used in this setting.

Phase I trial of obatoclax mesylate in combination with bortezomib for treatment of relapsed multiple myeloma

8013

Background: Obatoclax mesylate (GX15-070MS) is a BH3 mimetic that inhibits Bcl-2 protein family members including MCL-1, a dominant target in myeloma (MM). Obatoclax (OBX) inhibited viability of 14 MM cell lines (mean IC50 215 nM) and primary MM samples while exhibiting pre clinical synergy with bortezomib (BTZ). Sensitivity correlated with basal levels of Mcl-1 and Bcl-XL, but not Bcl2, Bim, Bax or Bak expression. Methods: We report a phase I trial of OBX in combination with BTZ. Eligibility required measureable disease, > 1 prior MM therapy, ≤10 cycles of prior BTZ and did not progress on prior BTZ therapy, creatinine ≤2 ULN. Starting dose level 1 was OBX 14 mg/m2 24-hour continuous iv. infusion days 1, 8, 15 of a 21-day cycle. BTZ given at 1.3mg/m2 iv. days 1, 4, 8 and 11. After protocol amendment OBX level 1 dosing was 30 mg/m2, level 2 was 40 mg/m2 IV both by continuous 3 hour infusion days 1, 8 and 15 on a 21 day schedule. Pre med. with famotidine was required. Results: Eleven patients were accrued, median age 62 (range: 46-77), median time from diagnosis was 4.7 years. Median of 2.5 cycles (range: 1-10). Median follow-up for patients still alive is 11.6 months (range: 0.9-35.5). At dose level 1, there were 2 DLTs. After amendment 8 patients were accrued (3 hour infusion): 4 at amended dose level 1 and 4 at dose level 2. All patients are now off treatment. 10 patients are evaluable for response: 2 patients at original dose level 1 (2 PR), 3 patients at dose level 1 (2 PR, 1 MR), no patients at dose level 2 responded: overall PR of 40%, clinical benefit response in 50% (95% CI: 19-81%). 6 patients had disease progression and 2 patients died. 4 DLTs were seen: at original dose level 1 grade 4 thrombocytopenia and delay of therapy > 15 days. At dose level 2, 1 patient had grade 3 somnolence, a 2nd patient grade 3 euphoria and grade 4 thrombocytopenia. No DLTs were seen at amended dose level 1. Common adverse events of any grade included GI, hematologic and neurologic e.g. euphoria, decreased level of consciousness, psychosis, speech. Conclusions: In summary MTD is OBX 30mg/m2 by 3 hour iv infusion once weekly, BTZ 1.3 mg/m2 days 1,4,8, and 11. Major toxicities were central neurologic and hematologic. This P2C consortium study was supported by NCI N01-CM62205.

A first-in-human phase I study of the oral p38 MAPK inhibitor LY2228820 dimesylate in patients with advanced cancer

3001

Background: p38 MAPK regulates production of cytokines by the tumor microenvironment and its activation enables cancer cells to survive in the presence of oncogenic stress, radiation, chemotherapy, and targeted therapies. LY2228820 is a selective small-molecule inhibitor of p38 MAPK and preclinical studies demonstrate antitumor activity as a single agent and in combination with standard agents. We performed a phase I study to determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of LY2228820 and to characterize its pharmacokinetics and pharmacodynamics. Methods: Dose escalation was performed in a 3+3 design. LY2228820 was taken orally every 12 hours on days 1-14 of a 28-day cycle. Results: 54 patients received either capsules at 8 dose levels (10, 20, 40, 65, 90, 120, 160, and 200mg) or tablets at 5 dose levels (160, 200, 300, 420, and 560mg). For both formulations, Cmax and AUC increased in a dose-dependent manner. LY2228820 inhibited p38 MAPK induced phosphorylation of MAPKAP-K2 in peripheral blood with dose-dependent maximum inhibition from 10 to 70% across the dose range 10-200mg. The most common drug-related adverse events included fatigue, nausea, rash, constipation, vomiting, and pruritus. 1 patient (200mg) had DLT of erythema multiforme (Gr3) and 2 patients (560mg) had DLT of ataxia (Gr3) and dizziness (Gr2), respectively. Although the MTD was 420mg, the frequency of Gr1/2 adverse events (mainly rash, dizziness, and tremor) and observation of clinical activity at lower dose levels led to a recommended dose of 300mg (mean AUC0-24 = 11.7ug-hr/ml at steady state). Early clinical activity has been observed in ovary, breast, and kidney cancers. One patient with metastatic clear cell carcinoma of the kidney refractory to sorafenib, sunitinib, and temsirolimus had confirmed near partial response (29% decrease) after 8 cycles and remains on therapy. 15 patients (28%) achieved best overall response of stable disease, which in 12 patients (22%) was prolonged (≥4 cycles). Conclusions: LY2228820 demonstrates acceptable pharmacokinetics, safety, and early clinical activity as a single agent in advanced cancer. A phase II study for patients with ovary cancer is planned.

A phase II trial of temsirolimus (TEM) and bevacizumab (BEV) in patients with advanced hepatocellular carcinoma (HCC)

4099

Background: There is strong rationale to combine an m-TOR inhibitor (TEM) with a VEGF inhibitor (BEV) as a potentially active and well tolerated treatment for HCC. Both agents have shown modest single agent activity in HCC and so evaluated here in a phase II trial. Methods: A modified 2-stage Simon design planned 25 or 50 patients (pts) to test the null hypothesis that true tumor response rate is at most 10% andtrue 6-mo progression-free survival rate (PFS) (by RECIST) is at most 65%, or no better than single agent BEV (6 mo PR >2 pts or PFS 6 mo >18 out of 25.) Toxicity, TTP, PFS and survival were 2nd endpoints. Eligible pts had confirmed HCC with disease unresectable or amenable to other localised therapies, Child Pugh A liver status and no prior systemic therapy involving the VEGF or m-TOR class of agents. TEM was administered at starting dose 25 mg IV d1,8,15,22 with BEV at 10mg/kg IV d 1, 15, all q 28 days (1 cycle). Imaging was q 8 wks. Results: From 09/09 to 09/11, 27 eligible pts were enrolled with 25 evaluable for toxicity and efficacy. Med age 59 yrs, 85% male, PS 0/1: 35/65, 58% metastatic, >85% BCLC stage C. With med 6 cycles (range 1-14) delivered, most pts (88%) experienced a grade 3+ adverse event (a/e.) Common grade 3 a/es related to treatment included thrombocytopenia (40%), neutropenia (20%), leucopenia (12%), fatigue (8%), anemia, mucositis, dyspnea, diarrhea, bleeds, fistula, infections (4% each). There was one possible treatment related death. Per protocol dose reductions/discontinuation for TEM-related a/es were most common. There were 2 confirmed PRs and 16 pts progression-free by 6 mos. A third pt developed a late PR at cycle 13. Median TTP on study was 6 mos, median PFS was 7.4 mos and median survival was 8.3 mos, with 13 pts still alive. Accrual closed at end of stage 1 as neither the number of responses nor the PFS at 6 mos passed the futility stopping rule set for this combination. Conclusions: This multicenter study is the first HCC trial evaluating the BEV/TEM doublet. Despite manageable toxicity, the ORR and 6 mo PFS did not surpass assumptions based on single agent BEV in HCC. Further study of BEV/TEM combination in this advanced HCC population is not recommended.

Phase 2 study of bevacizumab plus erlotinib in patients with advanced hepatocellular cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) are rational targets for therapy in hepatocellular cancer (HCC).

METHODS

Patients with histologically proven HCC and not amenable to curative or liver directed therapy were included in this 2-stage phase 2 trial. Eligibility included an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 or 1 and Child's Pugh score of A or B, and 1 prior systemic therapy. Patients received erlotinib 150 mg daily and bevacizumab 10 mg/kg on days 1 and 15 every 28 days. Objective tumor response was the primary end point.

RESULTS

Twenty-seven patients with advanced HCC (median age, 60 years) were enrolled in this multi-institutional study. The proportion of patients with Child's A classification was 74%. One patient had a confirmed partial response and 11 (48%) achieved stable disease. Median time to disease progression was 3.0 months (95% confidence interval [CI], 1.8-7.1). Median survival time was 9.5 months (95% CI, 7.1-17.1). Grade 3 toxicities included rash, hypertension, fatigue, and diarrhea.

CONCLUSIONS

In this trial, erlotinib combined with bevacizumab had minimal activity in patients with advanced HCC based on objective response and progression-free survival. The role of targeting EGFR and VEGF in HCC needs further evaluation in molecularly selected patients.

Development of a multidisciplinary, multicampus subspecialty practice in endocrine cancers

OBJECTIVES

Relative to more abundant neoplasms, endocrine cancers have been historically neglected, yet their incidence is increasing. We therefore sought to build interest in endocrine cancers, improve physician experience, and develop innovative approaches to treating patients with these neoplasms.

METHODS

Between 2005 and 2010, we developed a multidisciplinary Endocrine Malignancies Disease Oriented Group involving all 3 Mayo Clinic campuses (Rochester, Minnesota; Jacksonville, Florida; and Scottsdale, Arizona). In response to higher demand at the Rochester campus, we sought to develop a Subspecialty Tumor Group and an Endocrine Malignancies Tumor Clinic within the Division of Medical Oncology.

RESULTS

The intended groups were successfully formed. We experienced difficulty in integration of the Mayo Scottsdale campus resulting from local uncertainty as to whether patient volumes would be sufficient to sustain the effort at that campus and difficulty in developing enthusiasm among clinicians otherwise engaged in a busy clinical practice. But these obstacles were ultimately overcome. In addition, with respect to the newly formed medical oncology subspecialty endocrine malignancies group, appointment volumes quadrupled within the first year and increased 7 times within 2 years. The number of active therapeutic endocrine malignancies clinical trials also increased from 1 in 2005 to 5 in 2009, with all 3 Mayo campuses participating.

CONCLUSIONS

The development of subspecialty tumor groups for uncommon malignancies represents an effective approach to building experience, increasing patient volumes and referrals, and fostering development of increased therapeutic options and clinical trials for patients afflicted with otherwise historically neglected cancers.

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

260

Background: Recent placebo-controlled phase III trials of the mTOR inhibitor everolimus and the VEGF/ PDGF receptor inhibitor sunitinib in PNET noted improved progression-free survival (PFS). However, objective response rates (RR) with these agents are <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 is 50 patients, with interim analysis 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: Confirmed PR was documented in 11 of the first 25 (44%) evaluable patients. 20 of 25 (80%) patients were progression-free at 6 months. Both endpoints exceeded pre-defined criteria to continue enrollment. For 35 evaluable patients, the most common grade 3-4 adverse events attributed to therapy were leukopenia (12%), hypertension (12%), hyperglycemia (12%), mucositis (9%), and fatigue (9%).

Conclusions: The combination of TEM/BEV has substantial activity in a multi-center phase II trial with RR of 44%, 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. Accrual is ongoing. Supported by NCI N01 Contracts: 662205, 62203, 62208, 62209, 62206, 62204, 62207, 62201.

Efficacy of belinostat in advanced hepatocellular carcinoma (HCC): Phase I and II multicentered study of the Mayo Phase 2 Consortium (P2C) and the Cancer Therapeutics Research Group (CTRG)

259

Background: Belinostat is a novel histone deactylase inhibitor which demonstrates preclinical activity in HCC. We report the results of a phase I/II study on belinostat in patients (pts) with unresectable HCC.

Methods: Major eligibility criteria included histologically confirmed HCC not amenable to curative treatment; PS ≤ 2; adequate organ function; prior systemic therapy was allowed. In the phase I portion, belinostat was given i.v. on D1-5 every 3 weeks with dose levels of 600, 900, 1200 and 1400 mg/m2/day. In the phase II portion, belinostat was tested at the MTD. Primary endpoint was PFS and secondary endpoints were RR according to RECIST and OS. CT assessment was done every 8 weeks.

Results: Phase I portion: a total of 18 pts were accrued; no DLTs were observed at 1400mg/m2/day for 5 days, and this dose was selected for phase II development. Phase II portion: 42 pts were accrued; Median age = 57.5 years; 41 had Child’s A function, and 24 pt had ECOG 0. Sixteen (38%) had previous systemic therapy, and 21 (50%) had previous transarterial therapy. Median follow-up was 20.0 months. The PR and SD rate was 2.4% (1/42) and 45.2% (19/42). Median PFS was 2.64 months (95%C.I. 1.55-3.17) and OS was 6.60 months (95%C.I. 4.53-11.60). Grade 3 or higher toxicities (>5% rate) were abdominal pain (9.5%), (9.5%) hyperbilirubinemia (9.5%), raised ALT (9.5%); anemia (7.1%) and vomiting (7.1%).

Conclusions: Belinostat demonstrates disease stabilization in a predominantly pretreated population of pts with unresectable HCC with an acceptable safety profile. Further randomized studies are warranted.Supported in part by N01-CM-62205.

A phase II study of gemcitabine in combination with tanespimycin in advanced epithelial ovarian and primary peritoneal carcinoma

OBJECTIVE

To evaluate the efficacy and biological effects of the gemcitabine/tanespimycin combination in patients with advanced ovarian and peritoneal cancer. To assess the effect of tanespimycin on tumor cells, levels of the chaperone proteins HSP90 and HSP70 were examined in peripheral blood mononuclear cells (PBMC) and paired tumor biopsy lysates.

METHODS

Two-cohort phase II clinical trial. Patients were grouped according to prior gemcitabine therapy. All participants received tanespimycin 154 mg/m(2) on days 1 and 9 of cycle 1 and days 2 and 9 of subsequent cycles. Patients also received gemcitabine 750 mg/m(2) on day 8 of the first treatment cycle and days 1 and 8 of subsequent cycles.

RESULTS

The tanespimycin/gemcitabine combination induced a partial response in 1 gemcitabine naïve patient and no partial responses in gemcitabine resistant patients. Stable disease was seen in 6 patients (2 gemcitabine naïve and 4 gemcitabine resistant). The most common toxicities were hematologic (anemia and neutropenia) as well as nausea and vomiting. Immunoblotting demonstrated limited upregulation of HSP70 but little or no change in levels of most client proteins in PBMC and paired tumor samples.

CONCLUSIONS

Although well tolerated, the tanespimycin/gemcitabine combination exhibited limited anticancer activity in patients with advanced epithelial ovarian and primary peritoneal carcinoma, perhaps because of failure to significantly downregulate the client proteins at clinically achievable exposures.

Denileukin diftitox in combination with rituximab for previously untreated follicular B-cell non-Hodgkin's lymphoma

Follicular lymphoma exhibits intratumoral infiltration by non-malignant T lymphocytes inluding CD4+CD25+ regulatory T (T_reg) cells. We combined denileukin diftitox with rituximab in previously untreated, advanced-stage follicular lymphoma patients anticipating that denileukin diftitox would deplete CD25+ T_reg cells while rituximab would deplete malignant B-cells. Patients received rituximab 375 mg/m2 weekly for 4 weeks and denileukin diftitox 18 mcg/kg/day for 5 days every 3 weeks for 4 cycles; neither agent was given as maintenance therapy. Between August 2008 and March 2010, 24 patients were enrolled. One patient died before treatment was given and was not included in the analysis. Eleven of 23 patients (48%; 95% CI: 27–69%) responded; 2 (9%) had complete responses and 9 (39%) had partial responses. The progression-free rate at 2 years was 55% (95%CI: 37–82%). Thirteen patients (57%) experienced grade ≥3 adverse events and 1 patient (4%) died. In correlative studies, soluble CD25 and the number of CD25+ T-cells decreased after treatment, however there was a compensatory increase in IL-15 and IP-10. We conclude that while the addition of denileukin diftitox to rituximab decreased the number of CD25+ T-cells, denileukin diftitox contributed to the toxicity of the combination without an improvement in response rate or time to progression.

Phase I study of temsirolimus in combination with EKB-569 in patients with advanced solid tumors

Purpose Activation of EGFR can stimulate proliferative and survival signaling through mTOR. Preclinical data demonstrates synergistic activity of combined EGFR and mTOR inhibition. We undertook a phase I trial of temsirolimus (T, an mTOR inhibitor) and EKB-569 (E, an EGFR inhibitor) to determine the safety and tolerability. Methods The primary aim was to determine the maximally tolerated dose (MTD) of this combination in adults with solid tumors. Following the dose-escalation phase, (Cohort A), two subsequent cohorts were used to assess any pharmacokinetic (PK) interaction between the agents. Results Forty eight patients were enrolled. The MTD of this combination was E, 35 mg daily and T, 30 mg on days 1-3 and 15-17 using a 28-day cycle. The most common toxicities were nausea, diarrhea, fatigue, anorexia, stomatitis, rash, anemia, neutropenia, thrombocytopenia, and hypertriglyceridemia. Sixteen patients (36%) had at least one grade 3 toxicity. The most frequent grade 3/4 toxicities were diarrhea, dehydration, and nausea and vomiting (19% each). No grade 5 events were seen. Four patients had a partial response and 15 had stable disease. Clinical benefit was seen across a range of tumor types and in all cohorts. PK analysis revealed no significant interaction between E and T. Conclusions This combination of agents is associated with tolerable toxicities at doses that induced responses. PK studies revealed no interaction between the drugs. Further investigations of this targeting strategy may be attractive in renal cell carcinoma, non-small cell lung cancer, alveolar sarcoma, and carcinoid tumor.

Drug efflux by breast cancer resistance protein is a mechanism of resistance to the benzimidazole insulin-like growth factor receptor/insulin receptor inhibitor, BMS-536924

Preclinical investigations have identified insulin-like growth factor (IGF) signaling as a key mechanism for cancer growth and resistance to clinically useful therapies in multiple tumor types including breast cancer. Thus, agents targeting and blocking IGF signaling have promise in the treatment of solid tumors. To identify possible mechanisms of resistance to blocking the IGF pathway, we generated a cell line that was resistant to the IGF-1R/InsR benzimidazole inhibitors, BMS-554417 and BMS-536924, and compared expression profiles of the parental and resistant cells lines using Affymetrix GeneChip Human Genome U133 arrays. Compared with MCF-7 cells, breast cancer resistance protein (BCRP) expression was increased 9-fold in MCF-7R4, which was confirmed by immunoblotting and was highly statistically significant (P = 7.13E-09). BCRP was also upregulated in an independently derived resistant cell line, MCF-7 924R. MCF-7R4 cells had significantly lower intracellular accumulation of BMS-536924 compared with MCF-7 cells. Expression of BCRP in MCF-7 cells was sufficient to reduce sensitivity to BMS-536924. Furthermore, knockdown of BCRP in MCF-7R4 cells resensitized cells to BMS-536924. Four cell lines selected for resistance to the pyrrolotriazine IGF-1R/InsR inhibitor, BMS-754807, did not have upregulation of BCRP. These data suggest that benzimidazole IGF-1R/InsR inhibitors may select for upregulation and be effluxed by the ATP-binding cassette transporter, BCRP, contributing to resistance. However, pyrrolotriazine IGF-1R/InsR inhibitors do not appear to be affected by this resistance mechanism.

Phase I and pharmacological study of cytarabine and tanespimycin in relapsed and refractory acute leukemia

BACKGROUND

In preclinical studies the heat shock protein 90 (Hsp90) inhibitor tanespimycin induced down-regulation of checkpoint kinase 1 (Chk1) and other client proteins as well as increased sensitivity of acute leukemia cells to cytarabine. We report here the results of a phase I and pharmacological study of the cytarabine + tanespimycin combination in adults with recurrent or refractory acute leukemia.

DESIGN AND METHODS

Patients received cytarabine 400 mg/m(2)/day continuously for 5 days and tanespimycin infusions at escalating doses on days 3 and 6. Marrow mononuclear cells harvested before therapy, immediately prior to tanespimycin, and 24 hours later were examined by immunoblotting for Hsp70 and multiple Hsp90 clients.

RESULTS

Twenty-six patients were treated at five dose levels. The maximum tolerated dose was cytarabine 400 mg/m(2)/day for 5 days along with tanespimycin 300 mg/m(2) on days 3 and 6. Treatment-related adverse events included disseminated intravascular coagulation (grades 3 and 5), acute respiratory distress syndrome (grade 4), and myocardial infarction associated with prolonged exposure to tanespimycin and its active metabolite 17-aminogeldanamycin. Among 21 evaluable patients, there were two complete and four partial remissions. Elevations of Hsp70, a marker used to assess Hsp90 inhibition in other studies, were observed in more than 80% of samples harvested 24 hours after tanespimycin, but down-regulation of Chk1 and other Hsp90 client proteins was modest.

CONCLUSIONS

Because exposure to potentially effective concentrations occurs only for a brief time in vivo, at clinically tolerable doses tanespimycin has little effect on resistance-mediating client proteins in relapsed leukemia and exhibits limited activity in combination with cytarabine. (Clinicaltrials.gov identifier: NCT00098423).

Poly(ADP-Ribose) polymerase inhibition synergizes with 5-fluorodeoxyuridine but not 5-fluorouracil in ovarian cancer cells

5-Fluorouracil (5-FU) and 5-fluorodeoxyuridine (FdUrd, floxuridine) have activity in multiple tumors, and both agents undergo intracellular processing to active metabolites that disrupt RNA and DNA metabolism. These agents cause imbalances in deoxynucleotide triphosphate levels and the accumulation of uracil and 5-FU in the genome, events that activate the ATR- and ATM-dependent checkpoint signaling pathways and the base excision repair (BER) pathway. Here, we assessed which DNA damage response and repair processes influence 5-FU and FdUrd toxicity in ovarian cancer cells. These studies revealed that disabling the ATM, ATR, or BER pathways using small inhibitory RNAs did not affect 5-FU cytotoxicity. In stark contrast, ATR and a functional BER pathway protected FdUrd-treated cells. Consistent with a role for the BER pathway, the poly(ADP-ribose) polymerase (PARP) inhibitors ABT-888 (veliparib) and AZD2281 (olaparib) markedly synergized with FdUrd but not with 5-FU in ovarian cancer cell lines. Furthermore, ABT-888 synergized with FdUrd far more effectively than other agents commonly used to treat ovarian cancer. These findings underscore differences in the cytotoxic mechanisms of 5-FU and FdUrd and suggest that combining FdUrd and PARP inhibitors may be an innovative therapeutic strategy for ovarian tumors.

Temsirolimus and rituximab in patients with relapsed or refractory mantle cell lymphoma: a phase 2 study

BACKGROUND

Temsirolimus is a mammalian target of rapamycin (mTOR) inhibitor with single-agent antitumour activity in patients with mantle cell lymphoma. We therefore tested its efficacy and toxicity in combination with rituximab (an antiCD20 antibody) in patients with relapsed or refractory mantle cell lymphoma.

METHODS

In a phase 2 study, patients (aged ≥18 years) at 35 centres in the USA were given temsirolimus 25 mg/week, and rituximab 375 mg/m(2) per week for 4 weeks during the first cycle and thereafter a single dose of rituximab every other 28-day cycle. Both drugs were administered intravenously. Responding patients after six cycles could continue treatment for a total of 12 cycles, and were then observed without additional maintenance treatment. The primary endpoint was the proportion of patients with either rituximab-sensitive or rituximab-refractory disease who had at least a partial response. The analyses were done on all patients who were treated. The study was registered with ClinicalTrials.gov, number NCT00109967.

FINDINGS

71 patients with mantle cell lymphoma were enrolled and 69 were assessable and were included in the final analysis. The overall response rate (ORR) was 59% (41 of 69 patients)-13 (19%) patients had complete responses and 28 (41%) had partial responses. The ORR was 63% (30 of 48; 95% CI 47-76) for rituximab-sensitive patients, and 52% (11 of 21; 30-74) for rituximab-refractory patients. The most common treatment-related grade 3 or 4 adverse events in rituximab-sensitive and rituximab-refractory patients were thrombocytopenia (eight [17%] and eight [38%], respectively), neutropenia (ten [21%] and five [24%], respectively), fatigue (eight [17%] and two [10%], respectively), leucopenia (six [13%] and three [14%], respectively), pneumonia (five [10%] and two [10%], respectively), lymphopenia (five [10%] and two [10%], respectively), pneumonitis (four [8%] and none, respectively), oedema (four [8%] and none, respectively), dyspnoea (three [6%] and two [10%], respectively), and hypertriglyceridaemia (three [6%] and two [10%], respectively).

INTERPRETATION

mTOR inhibitors in combination with rituximab could have a role in the treatment of patients with relapsed and refractory mantle cell lymphoma.

FUNDING

National Institutes of Health and the Predolin Foundation.

Abstract 4712: Evidence of clinical efficacy of the combination of flavopiridol (Alvocidib) and cisplatin in platin-resistant ovarian and primary peritoneal carcinoma: Phase 2 trial MC0261

Background: Based upon preclinical synergy and prior phase 1 study results, the clinical efficacy of flavopiridol combined with cisplatin was assessed in patients with recurrent ovarian and primary peritoneal cancers.

Methods: A two cohort phase 2 trial of cisplatin (60 mg/m2 IV) followed by flavopiridol (100 mg/m2 IV, 24 h continuous infusion; 21 day cycles) was undertaken in patients with recurrent platin-sensitive or platin-resistant ovarian/primary peritoneal cancers (defined by disease progression &gt; vs. &lt;6 months following platin-based therapy). Measurable disease (RECIST criteria) – or evaluable disease plus CA125 &gt;2X the post-treatment nadir – was required, as was ECOG performance &lt;2 and exposure to only one prior treatment regimen.

Results: Forty-five patients were enrolled between April 20, 2004 and March 4, 2010 – 40 platin-resistant patients (Group 1), and 5 platin-sensitive patients (Group 2). In Group 1, the median number of treatment cycles was 3 (range 2-12); 39 of the 40 eligible patients have now discontinued treatment. While only 10% of all patients incurred grade 4 toxicities, grade 3 toxicities were seen in the majority (65%). The most frequent grade 3 and 4 toxicities were neutropenia (all grade 3, 17.5%); nausea (12.5%); vomiting, fatigue, thrombosis, anemia (10% each). Sensory neuropathy, grade 1 or 2, was observed in 75% of all patients – with grade 3 and 4 neuropathy not observed primarily due to pre-specified aggressive dose reductions. Six patients (15%) in Group 1 achieved a confirmed response (1 CR, 5 PR), with a median response duration of 119 days (range 84-212). Ten additional Group 1 patients (32.5%) experienced maintained stable disease. Median Group 1 overall time to progression was 3.7 months; overall survival was 17.2 months. Pilot assessment of attained ascites flavopiridol level and sensitivity of patient ascitic tumor cells to flavopiridol confirmed that patient flavopiridol levels were consistent with observed clinical antitumor efficacy. In Group 2, although 2 of 5 patients also responded (40%; 2 PR), the cohort was closed due to poor accrual.

Conclusions: The combination of flavopiridol and cisplatin has promising clinical activity in both platin-sensitive and platin-resistant ovarian and primary peritoneal cancers.

Supported in part by NCI CA097129, CA15083 and CM62205; clinicaltrials.gov identifier NCT00083122

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 4712. doi:10.1158/1538-7445.AM2011-4712

Abstract 1301: Investigation of a potential pharmacokinetic interaction between ABT-888 and topotecan in a phase I trial

Background: ABT-888 is an inhibitor of poly(ADP-ribose) polymerase1 (PARP1) and PARP2, two highly conserved enzymes implicated in DNA repair, maintenance of genomic stability, and regulation of transcription. Topotecan (TPT) is a water soluble camptothecin derivative with antitumor activity against ovarian tumors. The combination of ABT-888 with TPT is under investigation in phase I trials because PARP inhibition sensitizes tumors cells to TPT in vitro and in vivo. In those trials, the pharmacokinetics of TPT and ABT-888 are being studied to determine if ABT-888 levels are sufficient to modulate PARP activity and to investigate the potential interaction between TPT and ABT-888.

Methods: Advanced cancer patients with ECOG performance scores 0-2, adequate hematological, renal and hepatic function were treated with ABT-888 on days 1-3, 8-10, and 15-17 every 28 days. Topotecan was administered on days 2, 9 and 16 every 28 days. DLTs were defined as grade 4 neutropenia, grade 4 thrombocytopenia, grade 4 anemia or ≥ grade 3 non-hematologic toxicities despite maximal supportive care. ABT-888 and Toptoecan pharmacokinetics were characterized in all patients. Analysis of urinary recovery is ongoing.

Results: In this ongoing Phase I trial, 13 female patients with ovarian (n=12) or breast (n=1) cancer have been enrolled to date and pharmacokinetic data is available for 12 of those patients. ABT-888/TPT dose levels are: Level 1- 10 mg/ 2 mg/m2, Level 2- 20 mg/2 mg/m2, Level 3- 10 mg/3 mg/m2, and Level 4- 20 mg/3 mg/m2. The combination of ABT-888 with topotecan has been tolerable, with no dose limiting toxicity, and dose escalation continues at dose level 5. Topotecan t1/2 and clearance values were 3.0 ± 0.5 hrs and 9.50 ± 1.51 L/hr/m2 when administered alone, and were not affected by administration with ABT-888. When administered alone, ABT-888 t1/2, Cmax, AUC0-∞ values after the 10 mg dose were 8.2 ± 2.4 hrs, 432 ± 217 nM, and 2568 ± 1300 nM*hr, respectively. ABT-888 t1/2, Cmax, AUC values after the 20 mg dose were 5.7 ± 3.1 hrs, 600 ± 165 nM, and 3870± 934 respectively. When administered with TPT, ABT-888 t1/2, Cmax, AUC values after the 10 mg dose were 7.2 ± 2.1 hrs, 412 ± 283 nM, and 2705± 1089 nM*hr are: nM*hr respectively. ABT-888 t1/2, Cmax and AUC values after the 20 mg dose combined with TPT were 5.8 ± 2.2 hrs, 664 ± 97.6 nM, and 4283± 936 nM*hr respectively.

Conclusions: Plasma clearance of TPT and ABT-888 does not appear to be altered when they are administered together. The effect of co-administration of these agents on renal clearance is presently under investigation and those results will be presented. This work was supported by NIH grants R25 GM75148-04, U01CA069912-16S and MM01-RR00585.

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 1301. doi:10.1158/1538-7445.AM2011-1301

MC0553: A phase II safety and efficacy study with the VEGF receptor tyrosine kinase inhibitor pazopanib in patients with metastatic urothelial cancer

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Background: Vascular endothelial growth factor (VEGF) and platelet derived growth factor (PDGF) are produced by bladder cancer cell lines in vitro and expressed in human tumor tissues. Preclinical studies have also shown that bladder cancer cell lines express VEGF receptor 1 and 2 on their surface membrane. Pazopanib is a vascular endothelial receptor tyrosine kinase inhibitor with anti-angiogenesis and antitumor activity in several preclinical models. A two-stage phase II study was conducted to assess the activity and toxicity profile of pazopanib administered to patients with metastatic, urothelial carcinoma.

Methods: Patients with one prior systemic therapy for recurrent, metastatic urothelial carcinoma were eligible. Patients received pazopanib at a dose of 800 mg orally daily for 4 week cycle.

Results: Nineteen patients were enrolled. Median age was 66 years, with > 89% of patients presenting poorly differentiated bladder cancer. Adverse event data is available on 18 patients. No grade 4 or 5 events have been experienced. Nine patients have experienced 11 grade 3 adverse events of which 7 were deemed at least possibly related to treatment. Most common toxicities were anemia, thrombocytopenia, leucopenia and fatigue. For stage 1, none of the first 16 evaluable patients were deemed success (CR or PR) by the RECIST criteria during the first four 4-week cycles of treatment. Median progression- free survival was 1.9 months. This met the futility stopping rule of interim analysis, and therefore, the trial was recommended to be permanently closed. Correlative studies including measurement of VEGF levels in archived tissues and blood are pending.

Conclusions: Pazopanib did not show activity in urothelial carcinoma patients. The role of anti-VEGF therapies in urothelial carcinoma may need further evaluation in rational combination strategies.

[Table: see text]

A phase 2 study of temsirolimus (CCI-779) in patients with soft tissue sarcomas: a study of the Mayo phase 2 consortium (P2C)

BACKGROUND

The primary goal of this trial was to evaluate the confirmed response rate of temsirolimus (CCI-779), a mammalian target of rapamycin in patients with advanced soft tissue sarcomas (STS).

METHODS

Patients ≥18 years with measurable advanced STS, no prior chemotherapy for metastatic disease (adjuvant and neoadjuvant chemotherapy allowed), adequate organ function, and performance status of ≤2 were eligible. After premedication with an antihistamine, CCI-779 was given intravenously at 25 mg over 30 minutes on Days 1, 8, 15, and 22, repeated every 4 weeks. The primary endpoint was confirmed response rate per Response Evaluation Criteria in Solid Tumors.

RESULTS

Between June 2004 and November 2005, a total of 41 patients were enrolled and began treatment; 40 patients are evaluable for response and adverse events. The median age was 62 years (range, 28-72 years) with 56% women. Eighty percent had high-grade STS, and 22% had prior adjuvant chemotherapy. There were 2 patients (5%; 95% confidence interval [CI], 1-17) (undifferentiated fibrosarcoma and uterine leiomyosarcoma) who achieved a confirmed partial response lasting 3 and 17 months, respectively. Thirty-nine (95%) patients have progressed, with a median time to progression of 2.0 months (95% CI, 1.8-3.5). The median overall survival was 7.6 months (95% CI, 6.1-15.9). Forty-three percent experienced grade 3+ adverse events that were possibly related to therapy.

CONCLUSIONS

Temsirolimus in this patient population of STS had limited clinical activity and had moderate toxicities.

Phase II trials of single-agent anti-VEGF therapy for patients with chronic lymphocytic leukemia

Between 2005 and 2008, we conducted separate phase II clinical testing of three distinct anti-VEGF therapies for patients with relapsed/refractory CLL. Collectively, 46 patients were accrued to trials of single-agent anti-VEGF antibody (bevacizumab, n = 13) or one of two receptor tyrosine kinase inhibitors (AZD2171, n = 15; sunitinib malate, n = 18). All patients have completed treatment. Patients received a median of two cycles of bevacizumab, AZD2171, or sunitinib malate. All three trials were closed early due to lack of efficacy. No complete or partial remissions were observed. Individually and collectively, these studies indicate that single-agent anti-VEGF therapy has minimal clinical activity for patients with relapsed/refractory CLL.

Efficacy of pazopanib in progressive, radioiodine-refractory, metastatic differentiated thyroid cancers: results of a phase 2 consortium study

BACKGROUND

Chemotherapy has historically proven ineffective in advanced differentiated thyroid cancers, but the realisation that various tyrosine kinases are activated in the disease suggested a potential therapeutic role for tyrosine-kinase inhibitors. We investigated the safety and efficacy of pazopanib.

METHODS

This phase 2 trial was done from Feb 22, 2008, to Jan 31, 2009, in patients with metastatic, rapidly progressive, radioiodine-refractory differentiated thyroid cancers. Each patient received 800 mg continuous pazopanib daily in 4-week cycles until disease progression, drug intolerance, or both occurred. Up to two previous therapies were allowed, and measurable disease with radiographic progression in the 6-month period before enrolment was a requirement for inclusion. The primary endpoint was any tumour response, according to the Response Evaluation Criteria in Solid Tumors 1.0. This study is registered with ClinicalTrials.gov, number NCT00625846.

FINDINGS

39 patients were enrolled. One patient had received no previous radioiodine therapy and another withdrew consent before treatment. Clinical outcomes could, therefore, be assessed in 37 patients (19 [51%] men, median age 63 years). The study is closed to accrual of new patients, but several enrolled patients are still being treated. Patients received a median of 12 cycles (range 1 to >23, total >383). Confirmed partial responses were recorded in 18 patients (response rate 49%, 95% CI 35-68), with likelihood of response lasting longer than 1 year calculated to be 66%. Maximum concentration of pazopanib in plasma during cycle one was significantly correlated with radiographic response (r=-0·40, p=0·021). 16 (43%) patients required dose reductions owing to adverse events, the most frequent of which (any grade) were fatigue (29 patients), skin and hair hypopigmentation (28), diarrhoea (27), and nausea (27). Two patients who died during treatment had pre-existing contributory disorders.

INTERPRETATION

Pazopanib seems to represent a promising therapeutic option for patients with advanced differentiated thyroid cancers. The correlation of the patient's response and pazopanib concentration during the first cycle might indicate that treatment can be individualised to achieve optimum outcomes. Assessment of pazopanib in an expanded cohort of patients with differentiated thyroid cancer, as well as in cohorts of patients with medullary and anaplastic thyroid cancers, is presently being done.

FUNDING

National Cancer Institute, supported in part by NCI CA15083 and CM62205.

An international, multicenter phase II trial of bortezomib in patients with hepatocellular carcinoma

BACKGROUND AND RATIONALE

Bortezomib (PS-341, VELCADE®) is a selective inhibitor of the 26S proteasome, an integral component of the ubiquitin-proteasome pathway. This phase II study evaluated the activity and tolerability of bortezomib in unresectable hepatocellular carcinoma (HCC) patients.

METHODS

The primary endpoint was confirmed tumor response rate (RR) with secondary endpoints including duration of response, time to disease progression, survival and toxicity. Treatment consisted of bortezomib, 1.3 mg/m2 IV bolus on days 1, 4, 8, and 11 of each 21-day treatment cycle. Eligibility included: no prior systemic chemotherapy, ECOG PS 0-2, Child-Pugh A or B, preserved hematologic, hepatic and neurologic function; prior liver-directed therapy was permitted.

RESULTS

Thirty-five patients enrolled and received a median of 2 cycles of treatment (range 1-12). Overall, 24 and 4 patients had a maximum severity of grade 3 and 4 adverse events (AEs), respectively. No treatment related deaths occurred. Only thrombocytopenia (11%) was seen in greater than 10% of patients. One patient achieved a partial response, lasting 13 weeks during treatment and progressed 11.6 months later; two patients received treatment for greater than 6 months. Median time-to-progression was 1.6 months and median survival was 6.0 months.

CONCLUSIONS

This international, multicenter trial evaluated bortezomib as monotherapy in unresectable HCC patients. And, despite the lack of significant activity, this report serves as a baseline clinical experience for the development of future dual biologic approaches including bortezomib.

A study of paclitaxel, carboplatin, and bortezomib in the treatment of metastatic malignant melanoma: a phase 2 consortium study

BACKGROUND

Chemotherapy has not been reported to have a significant impact on survival for patients with metastatic melanoma. Bortezomib was shown to have additive/synergistic effects with several chemotherapeutic agents, including paclitaxel and platinum. A phase 1 trial of this 3-drug combination reported that 6 of 28 patients treated with bortezomib followed by paclitaxel and carboplatin achieved a partial response (including 2 of 5 patients with metastatic melanoma).

METHODS

A 2-stage phase 2 clinical trial was conducted to assess the antitumor activity of this 3-agent combination in patients with metastatic melanoma who had received at most 1 prior chemotherapy for metastatic disease. Treatment included bortezomib at a dose of 1.3 mg/m2 intravenously on Days 1, 4, and 8; paclitaxel at a dose of 175 mg/m2; and carboplatin at an area under the concentration (AUC) of 6 on Day 2 of a 21-day cycle. The primary endpoint of this trial was tumor response rate (TRR).

RESULTS

Seventeen eligible patients were enrolled. A median of 4 cycles were administered (range, 1-7 cycles). Three patients discontinued treatment due to persistent grade 4 (based on National Cancer Institute Common Terminology Criteria for Adverse Events [version 3.0]) neutropenia with grade 3 leukopenia (2 patients) or grade 4 pulmonary embolism (1 patient). Grade>or=3 toxicities included neutropenia (71%), leukopenia (41%), thrombocytopenia (29%), and arthralgia (12%). Two partial responses were observed (TRR, 11.8%). Four patients had stable disease at >12 weeks. The median progression-free survival was 3.2 months, and the median overall survival was 7.0 months.

CONCLUSIONS

Due to insufficient clinical efficacy, this trial did not proceed to second-stage accrual. The combination of paclitaxel, carboplatin, and bortezomib demonstrated limited clinical benefit and was associated with significant toxicity.