Haluska, Paul

3027 Background: Two rational strategies to interrogate the IGF-1R pathway were investigated in this parallel-arm phase I trial: 1) vertical inhibition with D and MK-2206 to potentiate PI3K pathway targeting, 2) horizontal crosstalk inhibition with D and MK-0752 to exert effects against cellular proliferation, angiogenesis and stem cell propagation. Methods: Patients (pts) with advanced solid tumors and no prior exposure to agents of the same targets were eligible. Dose escalation was based on a modified toxicity probability interval method (Ji et al, 2010). Arm A is comprised of fixed D dose of 10 mg/m2 IV weekly plus MK-2206 at escalating doses of 90-200 mg PO weekly. Arm B is comprised of fixed MK-0752 dose of 1800 mg PO weekly plus D at escalating doses of 7.5-10 mg/m2 IV weekly. Each cycle = 4 weeks in both arms. Primary objectives were to determine DLT and RP2D of these combinations. Results: 30 patients were enrolled in the dose escalation phase (18 in Arm A and 12 in Arm B) with: median age = 56 (range 36-74); M:F = 13:17; ECOG 0:1 = 12:18; primary diagnosis = colorectal (CRC) (9), NSCLC (3), others (17); prior metastatic regimens = 3 (range 1-4). In Arm A, 1/6 DLT was observed with MK-2206 at 135 mg (G3 serum sickness-like reaction); 2/3 DLTs with MK-2206 at 200 mg (G4 leukopenia/neutropenia; G3 rash). No other G4 or worse adverse events (AEs) were observed. RP2D of Arm A = D 10mg/m2 IV weekly and MK-2206 150 mg PO weekly. Other common AEs in Arm A included: fatigue, rash and nausea. In Arm B, 2/6 DLTs were observed with D at 10 mg/m2 (G3 rash; G3 nausea/vomiting). RP2D of Arm B = D 10mg/m2 IV weekly and MK-0752 at 1800 mg PO weekly based on Ji et al. Other common AEs in Arm B included: anorexia, nausea and fatigue. No PR was observed and SD > 4 months occurred in 4 pts (all in Arm A). PK analyses are ongoing. Conclusions: Targeted combinations of D with MK-2206 or with MK-0752 were both tolerable. Expansion cohorts based on biomarker selection are underway, specifically ovarian cancer with high IGF1 expression/low RAS score for Arm A; and KRAS wild-type CRC with high IGF1/low IGF2 expression for Arm B.

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.

TPS2618 Background: MEDI-573 is an investigational dual-targeting human antibody that neutralizes IGF-I/-II ligands and inhibits IGF‑1R and insulin receptor-A (IR-A) signaling pathways. By sparing IR-B and its hybrid receptors, MEDI-573 may achieve antitumor activity without perturbing glucose homeostasis. Objectives of this phase 1 dose-escalation and expansion study are to evaluate safety and determine the maximum tolerated dose (MTD), optimal biologically effective dose, pharmacokinetics, pharmacodynamics, and immunogenicity of MEDI-573 in adult patients with solid tumors. Methods: Patients with advanced solid tumors, Karnofsky status ≥60, and adequate organ function were treated with escalating doses of MEDI-573 IV once weekly (0.5 to 15 mg/kg) or every 3 weeks (30 or 45 mg/kg q3w) using a 3+3 design. Three patients per dose level were evaluated for safety. A biomarker-rich dose-expansion arm tested weekly 5 or 15 mg/kg MEDI‑573 in patients with advanced bladder cancer. Results: Preliminary data are presented for 43 patients (25 M, 18 F), median age 64 years. No dose-limiting toxicities or serious toxicity patterns occurred at any dose level. Drug-related adverse events occurring in ≥10% of patients were fatigue (28%), decreased appetite (23%), nausea (16%), diarrhea (14%), and anemia (12%); the majority were ≤ grade 2. Perturbations in insulin and growth hormone were not observed. Clinically significant changes in serum glucose were rare. The MTD was not reached after completely enrolling patients through the highest dose, 45 mg/kg IV q3w. Serum exposure of MEDI-573 increased with increasing dose. Full suppression of IGF‑I/-II was achieved with weekly and q3w dosing. No neutralizing antibodies against MEDI‑573 were detected. Of 43 patients, 8 (19%) had stable disease ≥12 weeks. The longest exposure was 21 months in a patient with well-differentiated liposarcoma. Conclusions: MEDI-573 demonstrated an acceptable safety profile at all doses tested. No dose-limiting toxicity or serious toxicities, including those related to glucose homeostasis, were detected. These preliminary results support further clinical development.

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]

5077 Background: A standard of care (SOC) for the adjuvant treatment of ovarian and primary peritoneal cancer is a platinum-based intravenous (IV) chemotherapy doublet. Intraperitoneal (IP) chemotherapy is also a SOC, but the high incidence of grade 3/4 adverse events has limited its acceptance among clinicians. To identify genetic markers for completion of IP chemotherapy, we analyzed SNPs in four genes known to play a role in metabolism of platinum or taxane drugs. Methods: Patients diagnosed with primary or recurrent stage III or IV epithelial ovarian or primary peritoneal cancer who had primary or secondary debulking surgery at Mayo Clinic (Rochester, MN) between January 2007 and February 2009 followed by IP chemotherapy were included in this study. A cycle was defined as IV paclitaxel (135mg/m2) on day one, IP cisplatin (100mg/ m2) on day two, and IP paclitaxel (60mg/ m2) on day eight. With prior consent from the patient, peripheral blood was obtained before treatment for extraction of germline DNA. Using a custom Illumina BeadXpress 96-plex panel, SNPs in GSTM1 (N=7), ABCB1 (N=57), CYP3A4 (N=7), and CYP2C8 (N=25) were genotyped. The association between SNPs in these subsets of genes and completion of IP chemotherapy was analyzed using linear regression. Results: Thirty-seven patients were included in this study and 16 (43.2%) completed IP chemotherapy. Twenty-two out of the fifty-seven ABCB1 SNP’s were associated with the number of cycles (p<0.15). There were no significant associations for GSTM1, CYP3A4 and CYP2C8 SNP’s. The minor A allele at missense SNP rs2229109 in the ABCB1 gene was present in five (31.2%) who completed treatment and only one (4.8%) who did not (p<0.007). However, the later was due to catheter complication. There was no association between rs2229109 and overall or progression-free survival. Conclusions: Our findings suggest that SNP rs2229109 in ABCB1 gene is associated with completion of IP chemotherapy, and potentially, less toxicity from chemotherapy. Thus, these patients may be optimal candidates for IP chemotherapy. Further studies in a larger population are needed.

5012 Background: VEGF receptor-mediated-signaling contributes to ovarian cancer pathogenesis. Elevated VEGF expression and serum levels are associated with poor clinical outcomes. We investigated RAM, a fully human VEGFR-2 antagonist antibody, in patients (pts) with persistent or recurrent EOC/FTC/PPC. Methods: Adult women with EOC/FTC/PPC who had completed ≥1 platinum (P)-based chemotherapeutic (ct) regimen and had a P-free interval (PFI) of <12 months (m), progression on, or persistent disease after P-based therapy were eligible. Any number of prior ct regimens was allowed. ECOG PS 0-1 and adequate organ function were required. Pts received 8 mg/kg RAM IV every 2 weeks. Primary endpoints were progression-free survival at 6m (PFS-6) and confirmed objective response rate (ORR) by RECIST 1.0. Results: 60 pts were treated; 1 remains on study as of Dec 2011. Median age was 62 years (range 27-80). Median number of prior regimens was 3 (range 1– 14). 51 pts (85%) received ≥ 2 prior regimens; 25 pts (42%) received >3 prior regimens. 45 pts (75%) were P resistant or refractory, with 65% (39 pts) serous tumors. PFS-6: 34.2% (95% CI: 21.7% – 47%). Best overall response: 3 PR (5%), 34 SD (57%), 20 PD (33%) and 3 not evaluable (5%). Median duration of PR: 5.6m (3.7, 5.6, 17.5); median PFS: 3.5m (95% CI: 2.3 – 5.3). Median OS: 11.1m (95% CI: 8.3 – 17.0). No unexpected toxicities were observed. Grade (G) 3 adverse events (AEs) observed in >5% of pts were: headache (10%) and fatigue (8%). No G4 AEs were observed in >5% of pts. 5 deaths occurred on RAM or within 30 days of discontinuation; 4 due to PD, and 1 due to intestinal perforation. 1 G4 bowel perforation and one G4 colo-vaginal fistula were noted. All 3 cases of perforation/fistula occurred in the setting of progressive, large-volume disease. Correlative biomarker studies are ongoing to identify patients most likely to benefit. Conclusions: Ramucirumab was reasonably tolerated and demonstrated single-agent activity in persistent or recurrent ovarian carcinoma, with approximately one-third of patients progression free at 6 months.

3586 Background: The insulin-like growth factor 1 receptor (IGF-IR), a tyrosine kinase, and its ligands (IGF-I & -2) are upregulated in many human tumors (e.g., breast, prostate, colon and non-small cell lung cancer) and enhance proliferative and prosurvival signaling. Inhibition of IGF-IR activation in tumor models suppresses tumor growth and increases tumor sensitivity to chemotherapy, supporting the development of agents targeting IGF-IR. CP-751,871 is a potent, highly specific, fully humanized, monoclonal antibody that inhibits IGF-IR autophosphorylation and induces receptor internalization. Methods: A Phase I dose escalation study was initiated to define the safety and tolerability, and to characterize the pharmacokinetic properties of CP-751,871 in patients with advanced solid tumors refractory to standard therapies. Results: Following informed consent and screening, a total of 24 patients with refractory solid tumors (e.g. colorectal, NSCLC, sarcoma and prostate cancer; 1–6 previous regimens) were enrolled. Patients received 3 to 20 mg/kg of CP-751,871 by IV infusion on Day 1 of 3-week cycles in four dose-escalation cohorts of 3 patients. No dose limiting toxicities were identified and the maximum feasible dose (MFD) cohort of 20 mg/kg was extended with 12 additional patients. No higher than grade 3 CTCAE v3.0 toxicities, attributed to study drug, have been so far reported. Grade 3 toxicities, all reported in patients dosed with 20 mg/kg of CP-751,871, are increased GGT (4%) and fatigue (4%). Grade 2 toxicities include: anorexia (7%), diarrhea (7%), increased GGT (4%), hyperglycemia (4%), fatigue (4%), increased urinary frequency (4%), nausea (4%), increased ALT (4%) and increased AST (4%). Pharmacokinetic analysis is currently ongoing. No objective responses were observed. At the MFD, patients received a median of 4 cycles (1–16). Three patients were stable for > 6 months and one patient, currently at cycle 16, remains on study. An additional cohort of 12 adrenocortical cancer patients is under evaluation. Conclusions: These data indicate that CP-751,871 is safe and well tolerated. Due to its good safety profile, CP-751,871 may constitute a suitable targeted agent to use in combination with approved therapies in multiple tumor types. No significant financial relationships to disclose.

3507 Purpose: To detect IGF-1R on circulating tumor cells (CTCs) as a biomarker in the clinical development of a monoclonal human antibody, CP-751,871, targeting IGF-1R. Experimental Design: An automated sample preparation and analysis system for enumerating CTCs (Celltracks) was adapted for detecting IGF-1R positive CTCs with a diagnostic antibody targeting a different IGF-1R epitope to CP-751,871. This assay was utilized in three phase I trials of CP-751,871 as a single agent or with chemotherapy and was validated using cell lines and blood samples from healthy volunteers and patients with metastatic carcinoma. Results: There was no interference between the analytical and therapeutic antibodies. CP-751,871 was well tolerated as a single agent, and in combination with docetaxel or carboplatin and paclitaxel, at doses ranging from 0.05 mg/kg to 20 mg/kg. Eighty patients were enrolled on phase 1 studies of CP-751,871, with 47 (59%) patients having CTCs detected during the study. Prior to treatment 26 patients (33%) had CTCs, with 23 having detectable IGF-1R positive CTCs. CP-751,871 alone, and CP-751,871 with cytotoxic chemotherapy, decreased CTCs and IGF-1R positive CTCs; these increased towards the end of the 21-day cycle in some patients, falling again with retreatment. CTCs were commonest in advanced hormone refractory prostate cancer (11/20). Detectable IGF-1R expression on CTCs before treatment with CP-751,871 and docetaxel was associated with a higher frequency of PSA decline by more than 50% (6/10 vs 2/8 patients). A relationship was observed between sustained falls in CTCs counts and PSA declines by more than 50%. Conclusions: IGF-1R expression is detectable by immunofluorescence on CTCs. These data support the further evaluation of CTCs in pharmacodynamic studies and patient selection, particularly in advanced prostate cancer. No significant financial relationships to disclose.