Phase II trial of vatalanib in patients with advanced or metastatic pancreatic adenocarcinoma after first-line gemcitabine therapy (PCRT O4-001)

PURPOSE

Vatalanib (PTK 787/ZK22584) is an oral poly-tyrosine kinase inhibitor with strong affinity for platelet-derived growth factor and vascular endothelial growth factor (VEGF) receptors. We conducted an open-label, phase II multicenter therapeutic trial investigating the efficacy and tolerability of vatalanib in patients with metastatic or advanced pancreatic cancer who failed first-line gemcitabine-based therapy.

METHODS

Vatalanib treatment consisted of a twice daily oral dosing using a "ramp-up schedule," beginning with 250 mg bid during week 1,500 mg bid during week 2, and 750 mg bid on week three and thereafter. The primary objective of this study was to evaluate the 6-month survival rate.

RESULTS

Sixty-seven patients were enrolled. The median age was 64, and 66% (N = 43) had only one prior regimen. Common grade 3/4 adverse events included hypertension (20%; N = 13), fatigue (17%; N = 11), abdominal pain (17%; N = 11), and elevated alkaline phosphatase (15%; N = 10). Among the 65 evaluable patients, the 6-month survival rate was 29% (95% CI 18-41%) and the median progression-free survival was 2 months. Fifteen patients survived 6 months or more. Two patients had objective partial responses, and 28% of patients had stable disease. Changes in biomarkers including soluble VEGF and vascular endothelial growth factor receptor did not correlate with response to drug.

CONCLUSION

Vatalanib was well tolerated as a second-line therapy and resulted in favorable 6-month survival rate in patients with metastatic pancreatic cancer, compared with historic controls.

Assessing the discordance rate between local and central HER2 testing in women with locally determined HER2-negative breast cancer

BACKGROUND

The importance of human epidermal growth factor receptor 2 (HER2) as a prognostic and predictive marker in invasive breast cancer is well established. Accurate assessment of HER2 status is essential to determine optimal treatment options.

METHODS

Breast cancer tumor tissue samples from the VIRGO observational cohort tissue substudy that were locally HER2-negative were retested centrally with both US Food and Drug Administration (FDA)-approved immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) assays, using FDA-approved assay cutoffs; results were compared.

RESULTS

Of the 552 unique patient samples centrally retested with local HER2-negative results recorded, tumor samples from 22 (4.0%) patients were determined to be HER2-positive (95% confidence interval [CI] = 2.5%-5.7%). Of these, 18 had been tested locally by only one testing methodology; 15 of 18 were HER2-positive after the central retesting, based on the testing methodology not performed locally. Compared with the 530 patients with centrally confirmed HER2-negative tumors, the 22 patients with centrally determined HER2-positive tumors were younger (median age 56.5 versus 60.0 years) and more likely to have ER/PR-negative tumors (27.3% versus 22.3%). These patients also had shorter median progression-free survival (6.4 months [95% CI = 3.8-15.9 months] versus 9.1 months [95% CI = 8.3-10.3 months]) and overall survival (25.9 months [95% CI = 13.8-not estimable] versus 27.9 months [95% CI = 25.0-32.9 months]).

CONCLUSIONS

This study highlights the limitations of employing just one HER2 testing methodology in current clinical practice. It identifies a cohort of patients who did not receive potentially efficacious therapy because their tumor HER2-positivity was not determined by the test initially used. Because of inherent limitations in testing methodologies, it is inadvisable to rely on a single test to rule out potential benefit from HER2-targeted therapy. Cancer 2014;120:2657–2664.

Abstract P2-16-17: Characterization of response to everolimus (EVE) in BOLERO-2: A phase 3 trial of EVE plus exemestane (EXE) in postmenopausal women with HR+, HER2- advanced breast cancer

Introduction: The BOLERO-2 trial demonstrated that combining the oral mammalian target of rapamycin (mTOR) inhibitor, EVE, with the steroidal aromatase inhibitor, EXE, more than doubled median progression-free survival (PFS) compared with placebo (PBO) plus EXE in postmenopausal women with hormone-receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2−) breast cancer (BC) who relapsed or progressed following a nonsteroidal aromatase inhibitor (NSAI). Patients also achieved responses per Response Evaluation Criteria in Solid Tumors (RECIST) during treatment with EVE+EXE.

Methods: The phase 3, double-blind, BOLERO-2 trial randomized postmenopausal women with HR+ BC progressing or recurring after NSAIs in a 2:1 manner to EVE 10 mg once daily plus EXE 25 mg once daily (EVE+EXE; n = 485) or placebo (PBO) plus EXE (PBO+EXE; n = 239). The primary endpoint was PFS by local assessment. Overall response rate (ORR; complete + partial response per investigator assessment based on RECIST 1.0) and duration of overall response were secondary endpoints. In addition, best percentage change from baseline in sum of longest diameters of target lesions was assessed.

Results: At the time of final PFS analyses at 18 months’ median follow-up, ORR was significantly higher in the EVE+EXE arm compared with the PBO+EXE arm (12.6% vs 1.7%, respectively, by local assessment; P<.0001). Among patients with measurable disease at baseline, 71% in the EVE+EXE arm had a decrease in the sum of longest diameters of target lesions compared with baseline vs 30% in the PBO+EXE arm. Median duration of overall response was 10.5 months (95% confidence interval [CI]: 8.2, 21.9 months) for EVE+EXE and 6.9 months (95% CI: 4.2, 6.9 months) for PBO+EXE. Of note, only 4 patients in the PBO+EXE arm had an objective response to treatment.

Conclusions: In addition to PFS, the combination of EVE plus EXE significantly improved ORR vs PBO+EXE in patients with HR+, HER2− advanced BC progressing during or after NSAI therapy. Furthermore, greater than two-thirds of patients treated with EVE+EXE experienced tumor shrinkage during treatment. These results further support the rationale for combining EVE with EXE to improve clinical outcomes in HR+, HER2− advanced BC progressing after NSAI therapy.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-16-17.

Addition of bevacizumab to three docetaxel regimens as adjuvant therapy for early stage breast cancer

Docetaxel-containing chemotherapy improves disease-free survival (DFS) and overall survival in patients with early stage breast cancer. Bevacizumab improves response rate and DFS in metastatic breast cancer. However, adding antivascular endothelial growth factor therapy to anthracycline-containing chemotherapy may increase cardiotoxicity. This trial evaluates the feasibility of adding bevacizumab to three standard adjuvant docetaxel regimens with a primary endpoint of grade ≥3 congestive heart failure (CHF). Phase IIb, randomized, non-comparative study of women with previously untreated node-positive or high-risk node-negative breast cancer. Human epidermal growth factor receptor 2 (HER2)-negative patients were randomized to: (arm A) doxorubicin + cyclophosphamide followed by docetaxel or (arm B) docetaxel + doxorubicin + cyclophosphamide. HER2-positive patients (arm C) received docetaxel + carboplatin + trastuzumab for 52 weeks. All patients received bevacizumab beginning on day 1 for 52 weeks. Safety data in 212 women (mean age = 53.1 years) show that 1 patient each in arm A (1.3 %) and arm C (1.7 %), and 3 patients in arm B (4.0 %) experienced clinical CHF grade ≥3. A decreased ejection fraction was observed in 1 patient each in arms A and C, and cardiac disorder was observed in 12.8, 22.7, and 8.5 % in arms A, B, and C, respectively. A grade 3/4 treatment-emergent adverse event was reported in 82.1, 84.0, and 52.5 % of participants in arms A, B, and C, respectively. Kaplan-Meier estimates of DFS show rates at 24 months of 85.5, 90.4, and 90.4 % in arms A, B, and C, respectively. Adding bevacizumab to three standard docetaxel-based chemotherapy regimens as adjuvant treatment in patients with node-positive and high-risk node-negative breast cancer resulted in a low rate of clinical CHF grade ≥3. Maintenance bevacizumab monotherapy did not identify any new safety signals. Breast cancer recurrence/relapse, secondary malignancies, and death were uncommon, although the follow-up time in this study was relatively short.

Abstract A218: Pharmacokinetics of orally administered rucaparib in patients with advanced solid tumors

Background: Oral cancer therapies are often complicated by variable absorption leading to highly variable plasma pharmacokinetics (PK) and thus unpredictable toxicity and efficacy. Rucaparib, a poly (ADP-ribose) polymerase inhibitor (PARPi), is being developed for treatment of tumors associated with homologous recombination repair deficiency with a pre-specified target plasma trough level. While efficacy has been shown for PARPis, dose interruptions/reductions due to adverse events (AEs) are common for PARPis. Here, we report the PK results for oral rucaparib in patients and assess exposure predictability.

Methods: Rucaparib PK was studied in two Phase I studies. CO-338-010 (N=39) is an ongoing Phase I/II monotherapy study examining safety, PK, and preliminary efficacy of oral rucaparib administered continuously 40-500 mg once (qd) or 240-600 mg twice daily (bid) (NCT01482715). The effect of a high-fat meal on rucaparib PK was examined at 40 mg (N=3) and 300 mg (N=6). A4991014 (N=53) is an ongoing Phase I study currently assessing rucaparib in combination with carboplatin (CBDCA) (NCT01009190). Patients received lead-in oral rucaparib on Day -5 followed by CBDCA on Day 1 and oral rucaparib qd on Days 1-14 of every 21-day treatment cycle. Patients in earlier cohorts also had a single lead-in dose of intravenous rucaparib for calculating oral bioavailability. Plasma rucaparib levels were determined using a validated LC-MS/MS method.

Results: Rucaparib exhibited good oral absorption with a dose-independent oral bioavailability of 36% and median Tmax ranging from 1 to 6 hours. Exposure generally exhibited dose proportional kinetics up to 1200 mg daily dose (600 mg bid). The target trough level of 2 μM was achieved in 100% of patients (n=14) at ≥240 mg bid with low inter-patient variability (<4-fold) within each dose group. Steady state trough levels also exhibited low intra-patient variability (24% CV). No sporadically high exposures were observed. In the combination study, rucaparib PK at doses of 80 to 360 mg qd was not meaningfully altered by concomitant AUC3 to AUC5 CBDCA. Rucaparib half-life of ∼17 hours was independent of dose. There was no food effect; patients may take rucaparib on an empty stomach or with food. Overall variability of exposure was low, both intra- and inter- patient.

Conclusions: Rucaparib showed desirable dose- and time- independent PK with low inter- and intra- patient variability in exposure compared to published olaparib data. Predictable PK following oral dosing may lead to low rates of over- and under- dosing, potentially minimizing AEs associated with high unpredictable exposures, an important attribute for maintenance therapy. Rucaparib's low inter-patient variability is beneficial for uniform flat dosing strategies. This will be explored in the two upcoming studies, ARIEL2 and ARIEL3.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A218.

Citation Format: Geoffrey Shapiro, Rebecca Kristeleit, Mark Middleton, Howard Burris, L. Rhoda Molife, Jeff Evans, Richard Wilson, Patricia LoRusso, James Spicer, Veronique Dieras, Manish Patel, Erin Dominy, Dayna Simpson, Heidi Giordano, Andrew R. Allen, Sarah S. Jaw-Tsai, Ruth Plummer. Pharmacokinetics of orally administered rucaparib in patients with advanced solid tumors. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A218.

Abstract LB-200: Dose and schedule determination of the Chk1/2 inhibitor LY2606368 in patients with solid tumors

Background: LY2606368 mesylate hydrate (LY2606368) is a Chk1/2 inhibitor. In addition to its role in DNA damage response, Chk1 also phosphorylates multiple downstream targets that regulate DNA replication, chromosome alignment, spindle checkpoints, and exit from cytokinesis. Since potent inhibition of Chk1 is predicted to generate DNA damage and mitotic catastrophe, this study evaluated LY2606368 as a single agent.

Methods: Two schedules of LY2606368 were assessed in this dose escalation study: dosing on days 1-3 every 14 days (Schedule [Sch] 1) and dosing on day 1 every 14 days (Sch 2). Patients were assessed for safety, tolerability, pharmacokinetics (PK), pharmacodynamic (PD), and dose-limiting toxicities (DLT).

Results: A total of 45 patients were enrolled, 27 of which were treated on Sch 1 at doses of 10-50 mg/m2 while 18 patients were treated on Sch 2 at doses of 40-130 mg/m2. The most frequently reported AE, regardless of schedule, was a transient (typically < 5 days) decrease in neutrophil count, which occurred in 93% of patients (Grade 4 in 73% of patients). A total of 3 patients (6.7%) experienced febrile neutropenia. Other common toxicities, regardless of causality, included white blood cell decrease (84%), anemia (73%), fatigue (56%), platelet count decreased (53%), nausea (36%), constipation (29%), anorexia (27%), vomiting (27%), dyspnea (20%), and fever (20%). The majority of the non-hematologic toxicities were CTCAE Grade 1/2 in severity. Hematologic toxicity was the dose limiting toxicity on both schedules. The MTD for Sch 1 was 40 mg/m2 and for Sch 2 was 105 mg/m2. The systemic exposure of LY2606368 increased in a dose-dependent manner across the dose range of 10-130 mg/m2 for both schedules. The LY2606368 half-life is suitable for achieving acceptable exposure while minimizing intra- and intercycle accumulation for either schedule. The exposure at MTD for both schedules is in the range that correlates to the minimal tumor response in nonclinical xenograft models. The nonclinical PK/PD model predicts an average pChk1% inhibition of ∼50% and ∼70% for 72 hours is required for minimum and maximum tumor responses, respectively. Simulations of human PK/PD profiles predict that the exposure and average pChk1% inhibition at the MTD of each schedule achieve the requirements for the minimum tumor response. One patient with SCC of the anus achieved a PR (60% reduction). Ten of the 45 patients (22%) achieved SD including 4/7 (57%) HNSCC patients (range on treatment: 3-7.5mo) that had received multiple prior therapies.

Conclusions: Based on the nonclinical PK/PD model, clinical human PK, human PD simulations, the similar safety profile, and the increased patient convenience, a dose of 105 mg/m2 of LY2606368, administered once every 14 days was selected as the schedule to further evaluate in Part B of the study, a dose expansion component which will focus on patients with squamous histology tumors.

Citation Format: Johanna C. Bendell, Filip Janku, Jeffrey Infante, Suzanne Jones, Howard Burris, Lisa Golden, Scott M. Hynes, Ji Lin, Aimee K. Bence, Susan Tse, Razelle Kurzrock, David Hong. Dose and schedule determination of the Chk1/2 inhibitor LY2606368 in patients with solid tumors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-200. doi:10.1158/1538-7445.AM2013-LB-200

Open-label extension study of the RNAi therapeutic ALN-VSP02 in cancer patients responding to therapy

3062

Background: ALN-VSP02 is an RNA interference (RNAi) therapeutic comprised of lipid nanoparticle-formulated small interfering RNAs targeting vascular endothelial growth factor (VEGF)-A and kinesin spindle protein (KSP). In a phase 1 trial, ALN-VSP02 administered as an iv infusion q2 wks was well-tolerated and showed evidence of anti-VEGF pharmacology and antitumor activity. Methods: Patients treated on the phase I trial with stable disease (SD) or better after 4 months (8 doses) were eligible to continue on an extension study until disease progression. Main objectives included continued evaluation of safety/tolerability and assessment of disease response. Results: Seven of 37 patients (18.9%) evaluable for response went onto the extension study, including 1 of 7 (14.2%) at 0.4 mg/kg, 2 of 5 (40%) at 0.7 mg/kg, and 4 of 11 (36.3%) at 1.0 mg/kg. All had progressed after one or more prior therapies. Tumor types included head and neck squamous cell carcinoma, angiosarcoma, endometrial cancer, renal cell carcinoma (RCC, N=2), and pancreatic neuroendocrine tumor (PNET, N=2). At the time of enrollment, 6 had SD and one (endometrial cancer with multiple liver metastases) had an unconfirmed partial response (PR). The average length of time on treatment (including phase I and extension studies) was 9.5 months (range 5-19). As of January 2012, 3 patients remain on study, including the endometrial cancer patient with an ongoing PR who has had >80% tumor regression after 19 months of treatment at 0.7 mg/kg and two patients with RCC and PNET with continued SD after nearly 1 year of treatment at 1.0 mg/kg. The other patients with RCC and PNET at 1.0 mg/kg with SD came off after 8.5 and 5.5 months, respectively, for adverse events that included fatigue or elevated alkaline phosphatase. A decrease in spleen volume, likely an on-target effect and not associated with any adverse events, occurred to a greater degree on the extension study than on the phase I trial and was most pronounced in patients receiving ≥ 12 doses. Conclusions: ALN-VSP02 has preliminary activity against endometrial cancer, RCC and PNET and a favorable safety profile that permits chronic dosing. Phase II trials are warranted in these and other VEGF-overexpressing tumors.

P1-17-02: A Phase 1/2 Study of SAR245408 (S08) in Combination with Trastuzumab (T) or Paclitaxel (P) and T in Patients with HER2+ Metastatic Breast Cancer (MBC) Who Progressed on a Previous T-Based Regimen

BACKGROUND: Most HER2+ MBC patients (pts) treated with a combination of T+P progress within 1 year. Activation of downstream pathways through either deficiency in PTEN or mutations in the PI3K pathway has been implicated in the development of resistance to T. S08 is a potent, orally bioavailable, pan-PI3K inhibitor that inhibits phosphorylation of multiple downstream components of the PI3K/PTEN signaling pathway and has demonstrated activity as a single agent and in combination with other anticancer agents (Edelman G, et al., ASCO 2010; Traynor AM, et al. ASCO 2010).

PATIENTS and METHODS: This ongoing, open-label multicenter phase 1/2 study (NCT01042925) was designed to assess safety and tolerability of S08 in combination with either T or T+P. Eligible female pts were ≥18 yrs, ECOG PS 0–2, with adequate organ and marrow function and had advanced or recurrent HER2+ MBC disease refractory to T. Pts have received, and progressed on at least 1 prior T-containing regimen for metastatic disease. Pts were allocated to Arm 1 or Arm 2 and received different dose levels of S08 (starting dose 200 mg PO, daily) in combination with either T 8/6 mg/kg IV on Day (D) 1 q3w (Arm 1) or T 8/6 mg/kg IV on D1 + P 80 mg/m2 on D 1, 8, and 15 q3w (Arm 2). In phase 1, a standard ascending 3 + 3 dose escalation design was used in each arm to evaluate safety/tolerability of the combinations. Following establishment of preliminary maximal tolerated doses (MTDs) for each combination, subsequent pts will be accrued to the phase 2 portion. Approximately 25 additional pts will be enrolled in each arm to further evaluate the safety and estimate the overall response rate (ORR) in each arm.

RESULTS: As of June 1st 2011, 33 pts median age 55 yrs were enrolled; 18 to Arm 1 and 15 to Arm 2. Based on preliminary data of the study, in Arm 1, the most common treatment emergent adverse events (TEAEs) regardless of relationship include rash, diarrhea, fatigue, nausea, vomiting; in Arm 2 were neutropenia, diarrhea, fatigue, nausea, hyporexia, hypokalemia, peripheral neuropathy, rash and hyperglycemia. SAEs reported in Arm 1 (3 subjects) included Gr3 dehydration (2 cases), Gr3 epigastric pain and Gr2 dyspnea; those SAEs in Arm 2 (4 subjects) included Gr4 neutropenia, Gr3 anorexia, Gr3 dehydration, Gr3 epigastric pain, Gr3 thromboembolism, Gr2 nausea, Gr2 pneumonitis and Gr2 headache. A total of 4 DLTs were reported; 2 in Arm 1 [Gr3 skin rash (S08; 400 mg dose)] and 2 in Arm 2 [Gr4 neutropenia (S08; 200mg dose)] (table 1). With phase I nearly complete, the MTD for arm 1 is S08 300 mg PO daily and T 8/6 mg/kg D1 q3w. The data for Arm 2 (current dose level ongoing at the maximum allowed per protocol) will be completed in August 2011. Preliminary PK data did not show interactions between S08 and either T or T+P.

P1-17-09: A Phase 1/2 Dose-Escalation Study of SAR245408 (S08) or SAR245409 (S09) in Combination with Letrozole (L) in Subjects with Hormone Receptor-Positive and HER2−Negative (HR+/HER2−) Breast Cancer (BC) Refractory to a Nonsteroidal Aromatase Inhibitor (AI)

Background: Upregulation of PI3K activity is a common molecular mechanism involved in resistance to AIs. S08 is a potent, orally bioavailable, pan-PI3K inhibitor. S09 is a potent, orally bioavailable inhibitor of PI3K which also possesses mTOR inhibitory activity. Both compounds exhibit robust PI3K and ERK pathway inhibition in paired human tumor biopsy samples from phase 1 studies (Edelman G, et al. ASCO 2010; Brana I, et al. ASCO 2010).

Methods: This ongoing, open-label, multicenter, phase 1/2 study (NCT01082068) was designed to evaluate the safety and tolerability of L in combination with either S08 (Arm 1) or S09 (Arm 2). Eligible female patients (pts) were ≥18 yrs, ECOG PS 0–1, with advanced or recurrent HR+/HER2− BC whose disease is refractory to nonsteroidal AIs. Phase 1 used an ascending 3+3 dose-escalation design and pts were accrued to each arm until no more than 1/3 pts or ≥33% of 3–6 pts at a given dose level experienced a dose-limiting toxicity (DLT) during the first 28-day cycle. Pts were alternately assigned to Arm 1 or Arm 2 and received 2.5 mg L PO (qd) in combination with different dose levels of either S08 (Arm 1; starting dose 200 mg tablets, PO, qd) or S09 (Arm 2; starting dose of 30 mg capsules, PO, bid). After reaching a preliminary maximum tolerated dose (MTD) for each combination, pts will accrue to the phase 2 portion of the study. A two-stage design will be used evaluate the phase 2 co-primary endpoints of ORR and PFS. Each arm will be evaluated independently and no formal comparisons between arms are planned.

Results: As of June 1st 2011, 17 pts were enrolled to Arm 1 (8 pts) or Arm 2 (9 pts). Median age was 54 yrs. Based on preliminary data, the adverse event profile in both arms were similar to those reported in the single agent phase I studies for S08 and S09 respectively. SAEs reported in Arm 1 (2 subjects) included 2 cases of Gr1 pneumothorax and 1 Gr4 pneumonitis; in Arm 2 (2 subjects) included Gr4 lumbar pain and Gr4 elevation of ALT and AST. No DLTs were reported in Arm 1 while one DLT (Gr3 skin rash) was reported in Arm 2 at a dose level of S09 50 mg bid (table 1). Arm 1 dosing data from S08 400 mg qd + L 2.5 mg qd dose level (maximum dose level allowed per protocol) will be completed by August 2011. For Arm 2, the MTD was S09 50 mg bid + L 2.5 mg, qd.

P1-07-02: Discordance between Central and Local Laboratory HER2 Testing from a Large HER2−Negative Population in VIRGO, a Metastatic Breast Cancer Registry

Background: HER2 overexpression is associated with unfavorable prognosis and is reported in 18–25% of breast cancers (BC). HER2 testing is often performed using immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH). Because of the significant benefit of HER2−directed therapies, it is critical to accurately identify women whose tumors are HER2+. Reports have noted discordance between HER2+ test results from local vs. large reference labs in patients with HER2+ BC evaluated for trastuzumab-based clinical studies. There are little published data on central testing of BC found to be negative locally.

Patients and Methods: VIRGO is an observational cohort of N=1,287 women with primarily HER2−negative metastatic BC. An optional tissue collection substudy was conducted, and 776 patient samples were received and centrally retested. Central testing was performed at 2 reference labs and tumors were deemed HER2+ if IHC 3+ and/or FISH positive (HER2:CEP17 ratio ≥2.0). Tumors with unknown/missing local HER2 status (n=68) were excluded from primary analyses. Number of patients potentially affected based on BC incidences from the American Cancer Society (ACS) 2011 estimates and the World Health Organization (WHO) 2008 report were calculated. Testing on the remainder of the HER2−negative cohort is in process.

Results: Central retesting has been performed on tumor samples from n=373 patients to date: HER2−negative locally evaluable tumors (n=301), n=4 HER2−negative locally with no evaluable tumor, and HER2 unknown (n=68). A total of 301 unique patient samples were included in the primary analysis. Of these, 15 (4.98% [95% CI (2.7%, 7.9%)] were found to be HER2+ by central testing (Table). Based on sensitivity analyses assuming all 68 tumors with unknown HER2 status to be negative locally, 4.07%(15 /369) would be centrally HER2+.

Abstract B56: A phase 1, open-label, dose escalation, nonrandomized study to assess the maximum tolerated dose, dose limiting toxicity, and pharmacokinetics of OPB-31121 in subjects with advanced solid tumors

Background: OPB-31121 is a novel compound exhibiting potent growth inhibition of cancer cell lines in vitro and xenografts in vivo. The exact mechanism of action of OPB-31121 has not been fully characterized, but studies indicate that a major effect is inhibition of STAT3 phosphorylation. STAT3 is frequently activated in a variety of solid and hematologic malignancies and may present an important target for antitumor therapy.

Methods: Open-label, non-randomized, multi-center study in subjects with advanced solid tumors, using a 3+3 dose escalation design. OPB-31121 was administered orally for 21 days followed by 7 days rest per cycle (28-day cycle). The starting dose was 50 mg BID with escalations planned until the dose-limiting toxicity (DLT) was reached. The primary endpoint was determination of maximum tolerated dose (MTD). Additional endpoints included safety, pharmacokinetics, and anti-tumor effect of OPB-31121.

Results: 30 subjects received treatment with OPB-31121. Most common tumor types were colorectal cancer (15), breast (3) and thyroid (2). Mean age was 55.9 (range 35–80) years and 17 of the patients were female. Most common adverse events (AEs) potentially attributed to treatment were gastrointestinal: nausea (80%), vomiting (73%), diarrhea (63%), anorexia (20%), and constipation (17%). Most AEs were CTCAE grades 1–2 and manageable with supportive treatment. Three DLTs were observed: one at 300 mg BID (grade 3 lactic acidosis), and two at 350 mg BID (a grade 3 diarrhea and a grade 3 vomiting); the MTD was 300 mg BID. All patients recovered from DLTs after discontinuing the drug. Six additional (9 total) subjects discontinued during the first cycle. Eight subjects completed only one cycle and 13 completed two cycles. No objective responses were observed. Disease progression was observed in all evaluable patients at first restaging. Pharmacokinetic measurements showed low and transient plasma levels of OPB-31121. Inter-patient variability was high. Exposure was low - area-under-the-curve (AUC) values were 2–3 orders of magnitude lower than those measured at active doses in mouse models. Analysis of metabolites in plasma samples indicates extensive CYP3A4 metabolism and suggests a large first-pass effect in humans, which had not been observed in rodents.

Conclusions: OPB-31121 does not show potential as a therapeutic option for most malignancies. The extensive first-pass metabolism and dose-limiting gastrointestinal AEs limit the level of systemic exposure that can be achieved with this agent. Further studies may be warranted in cancers of organs where local concentrations of the compound may be higher (e.g., liver) and an exploratory study in hepatocellular carcinoma is ongoing in Asia. Because STAT3 remains an attractive antitumor target, chemically related compounds with similar pharmacologic activities are currently being evaluated preclinically.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr B56.

Getting research into policy - Herpes simplex virus type-2 (HSV-2) treatment and HIV infection: international guidelines formulation and the case of Ghana

BACKGROUND

Observational epidemiological and biological data indicate clear synergies between Herpes simplex virus type 2 (HSV-2) and HIV, whereby HSV-2 enhances the potential for HIV acquisition or transmission. In 2001, the World Health Organization (WHO) launched a call for research into the possibilities of disrupting this cofactor effect through the use of antiherpetic therapy. A WHO Expert Meeting was convened in 2008 to review the research results. The results of the trials were mostly inconclusive or showed no impact. However, the WHO syndromic management treatment guidelines were modified to include acyclovir as first line therapy to treat genital ulcer disease on the basis of the high prevalence of HSV-2 in most settings, impact and cost-benefit of treatment on ulcer healing and quality of life among patients.

METHODS

This paper examines the process through which the evidence related to HIV-HSV-2 interactions influenced policy at the international level and then the mechanism of international to national policy transfer, with Ghana as a case study. To better understand the context within which national policy change occurs, special attention was paid to the relationships between researchers and policy-makers as integral to the process of getting evidence into policy. Data from this study were then collected through interviews conducted with researchers, program managers and policy-makers working in sexual health/STI at the 2008 WHO Expert Meeting in Montreux, Switzerland, and in Accra, Ghana.

RESULTS

The major findings of this study indicate that investigations into HSV-2 as a cofactor of HIV generated the political will necessary to reform HSV-2 treatment policy. Playing a pivotal role at both the international level and within the Ghanaian policy context were 'policy networks' formed either formally (WHO) or informally (Ghana) around an issue area. These networks of professionals serve as the primary conduit of information between researchers and policy-makers. Donor influence was cited as the single strongest impetus and impediment to policy change nationally.

CONCLUSIONS

Policy networks may serve as the primary driving force of change in both international context and in the case of Ghana. Communication among researchers and policy-makers is critical for uptake of evidence and opportunities may exist to formalize policy networks and engage donors in a productive and ethical way.

A phase I trial to determine the safety of imatinib in combination with vatalanib in patients with advanced malignancies

The role of tyrosine kinase inhibitors (TKIs) in the treatment of advanced malignancies is well established. Imatinib and vatalanib are oral TKIs with different mechanisms of action. This trial sought to establish the safety, tolerability, and maximum tolerated dose (MTD) of the two agents in combination. Secondary objectives included determination of potential pharmacologic interactions among vatalanib and imatinib and observation of antitumor activity. Patients with biopsy-proven advanced refractory solid tumors were enrolled in this single-center dose-escalation trial. Patients initially received imatinib and vatalanib once daily following a 14-day run-in period of daily oral vatalanib only, and were observed for a full 28-day treatment cycle prior to dose escalation. An amendment divided the vatalanib dose into two daily doses and gradually escalated the dose over a 2-3 week period. Patients continued combination therapy until disease progression or intolerable toxicity. Forty-five patients were enrolled between September 2004 and November 2007. As of September 2009, a total of 247 cycles of treatment had been administered (range: 1 -44+, median = 2 ). The MTD was determined to be vatalanib 1250 mg daily and imatinib 400 mg daily. Thirty-five patients (78%) were evaluable for response; 2 patients achieved PR, while 14 patients had SD ( 10 had stable disease ≥ 6 cycles). The combination of vatalanib and imatinib was well tolerated. Twice-daily vatalanib dosing improved tolerability and ease of full-dose administration. These results suggest that vatalanib-containing combinations may be active and tolerable, warranting further study.

Pharmacokinetics and antitumor activity of patupilone combined with midazolam or omeprazole in patients with advanced cancer

PURPOSE

Patupilone is a novel microtubule-targeting cytotoxic agent with potential interaction with CYP3A4/CYP2C19 enzymes. Midazolam and omeprazole are primarily metabolized by CYP3A4 and CYP2C19, respectively. We evaluated the inhibitory effects of patupilone on the CYP3A4/CYP2C19 pathways.

METHODS

This study had 2 parts: in an initial core phase, patients were randomly assigned to receive midazolam 4 mg or omeprazole 40 mg PO (days 1 and 29) and patupilone 10 mg/m(2) IV (days 8 and 29). Patients without progression continued patupilone every 3 weeks until disease progression or unacceptable toxicity (extension phase).

RESULTS

Forty-six patients were treated. The areas under the concentration-time curves (AUC)s of midazolam with or without patupilone co-administration were similar. The C (max) of midazolam when co-administered with patupilone was highly variable and was lower compared with midazolam alone; however, the oral clearance and terminal half-lives were similar. Both the C (max) and AUC of omeprazole when co-administered with patupilone were highly variable and lower than with omeprazole alone. However, the oral clearance and terminal half-lives were similar. The latter data suggest that patupilone decreased the absorption of omeprazole (by ~20%). The overall safety profile was consistent with that of previous single-agent patupilone studies; 2 partial responses (ovarian and pancreatic cancer) and 1 complete response (serous ovarian adenocarcinoma) were observed.

CONCLUSIONS

Patupilone was not a potent CYP3A4 or CYP2C19 inhibitor. No dose adjustment is required when omeprazole or midazolam is used in patients treated with patupilone. Patupilone exhibited promising antitumor activity in heavily pretreated patients with ovarian and pancreatic cancer.

Safety and pharmacokinetics of motesanib in combination with panitumumab and gemcitabine-Cisplatin in patients with advanced cancer

Purpose. The aim of this study was to assess the safety and tolerability of motesanib (an orally administered small-molecule antagonist of vascular endothelial growth factor receptors 1, 2, and 3, platelet-derived growth factor receptor, and Kit) when administered in combination with panitumumab, gemcitabine, and cisplatin. Methods. This was an open-label, multicenter phase 1b study in patients with advanced solid tumors with an ECOG performance status ≤1 and for whom a gemcitabine/cisplatin regimen was indicated. Patients received motesanib (0 mg [control], 50 mg once daily [QD], 75 mg QD, 100 mg QD, 125 mg QD, or 75 mg twice daily [BID]) with panitumumab (9 mg/kg), gemcitabine (1250 mg/m(2)) and cisplatin (75 mg/m(2)) in 21-day cycles. The primary endpoint was the incidence of dose-limiting toxicities (DLTs). Results. Forty-one patients were enrolled and received treatment (including 8 control patients). One of eight patients in the 50 mg QD cohort and 5/11 patients in the 125 mg QD cohort experienced DLTs. The maximum tolerated dose was established as 100 mg QD. Among patients who received motesanib (n = 33), 29 had motesanib-related adverse events. Fourteen patients had serious motesanib-related events. Ten patients had motesanib-related venous thromboembolic events and three had motesanib-related arterial thromboembolic events, two of which were considered serious. One patient had a complete response and nine had partial responses as their best objective response. Conclusions. The combination of motesanib, panitumumab, and gemcitabine/cisplatin could not be administered consistently and, at the described doses and schedule, may be intolerable. However, encouraging antitumor activity was noted in some cases.