Citations

Abstract Background: Polo-like kinase 1 (PLK1) is a serine/threonine kinase that regulates multiple critical aspects of cell progression. PLK1 is over-expressed in many human tumor types and its over-expression is a negative prognostic indicator of patient outcome in a variety of cancers. TKM-080301 is a lipid nanoparticle formulation of a small interfering RNA (siRNA) directed against PLK1 that has been shown to effect highly selective reductions in PLK1 mRNA in vitro and in tumor xenograft models in mice. Methods: A phase I multi-center, open-label, non-randomized, dose-escalation study of TKM-080301 is ongoing in patients with advanced solid tumors or lymphoma. Sequential cohorts of 3 to 6 patients receive TKM-080301 as a 30-minute IV infusion on Days 1, 8, and 15 of a 28-day cycle. Primary objectives include determination of safety, maximum tolerated dose (MTD) and dose limiting toxicities (DLTs). Secondary objectives include characterization of pharmacokinetics (PK) and preliminary assessment of anti-tumor activity and pharmacodynamic effects. Pre-and post-dose biopsy samples are being collected from patients treated after DLT has been established. Results: Twenty-three (23) patients, receiving a cumulative total of 128 doses, have been treated with TKM-080301 at doses ranging from 0.15 to 0.9 mg/kg/week. The most common drug-related adverse events have been mild-to-moderate infusion related reactions with delayed onset, pyrexia, chills, nausea, vomiting, and fatigue. Mild, transient increases in certain cytokines (e.g., IL-6, IL-8, MCP-1) have been observed at dose levels ≤0.75 mg/kg/week and generally correlated with the timing of delayed infusion reactions. DLTs were observed at 0.9 mg/kg/week and included hypoxia/dyspnea in one patient (with a previous history of asthma) and thrombocytopenia in another patient. The dose level was subsequently reduced to 0.75 mg/kg/week. Pharmacokinetic parameters determined after the first dose in Cycles 1 and 2 demonstrated dose proportional Cmax and AUC and no obvious accumulation. Two patients have received TKM-080301 for at least 6 months (6 cycles) with no evidence of cumulative toxicity, including one patient with stable disease (colon) and one patient with a durable confirmed partial response (carcinoid tumor) who has received 8+ cycles of treatment. Conclusions: Preliminary results from this first-in-human trial indicate TKM-080301 was generally well-tolerated by the majority of patients. Preliminary antitumor efficacy has been observed, supporting PLK1 as a therapeutic target. As two DLTs were observed at the dose of 0.9 mg/kg/week, patient accrual is continuing at the 0.75 mg/kg/week dose level. Citation Format: Ramesh K. Ramanathan, Solomon I. Hamburg, Mitesh J. Borad, Mahesh Seetharam, Madappa N. Kundranda, Peter Lee, Paul Fredlund, Mark Gilbert, Cathy Mast, Sean C. Semple, Adam D. Judge, Brynne Crowell, Linda Vocila, Ian MacLachlan, Donald W. Northfelt. A phase I dose escalation study of TKM-080301, a RNAi therapeutic directed against PLK1, in patients with advanced 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-289. doi:10.1158/1538-7445.AM2013-LB-289

Abstract Background: A previous feasibility trial (E2104 – Ann Oncol 23(2):331–7,2012) suggested incorporation of B into anthracycline-containing adjuvant therapy was feasible but ongoing cardiac monitoring was required to define the true impact of B on cardiac function. Methods: Patients (pts) were assigned 1:2:2 to one of three treatment arms. In addition to doxorubicin and cyclophosphamide followed by weekly paclitaxel, patients received either placebo (Arm A – AC>T) or B during chemotherapy (Arm B - BAC>BT), or B during chemotherapy followed by B monotherapy (15 mg/kg q3wk) for an additional 10 cycles (Arm C – BAC>BT>B). Randomization was stratified and B dose adjusted for choice of AC schedule (classical q3wk − 15 mg/kg; dose dense(dd) q2 wk − 10 mg/kg). When indicated, radiation and hormonal therapy were administered concurrently with B (for Arm C pts). The primary cardiac endpoint was the incidence of clinically apparent cardiac dysfunction (CHF)defined as symptomatic decline in left ventricular ejection fraction (LVEF) to below the lower limit of normal (LLN) or symptomatic diastolic dysfunction as assessed by independent review. Cumulative toxicity data as of Jan 23, 2012 are presented. Results: From 11.07 to 2.11, 4994 pts were enrolled. Median age was 52; 80% received ddAC. Chemotherapy associated toxicities including myelosuppression (Grade 4 neutropenia 16/20/19%) and neuropathy (Grade ≥ 3 8/8/8%) were similar across all arms. Grade ≥ 3 hypertension/thrombosis/proteinuria/hemorrhage was reported by 7/3/<1/<1% of B-treated pts. 99 pts developed CHF, most commonly reported at the post-AC or post-T evaluation. After a median follow-up of 26 months, the cumulative incidence of clinical CHF at 15 months from randomization in Arm A/B/C was 1.0/1.7/2.9% respectively. Median age of CHF pts was 57; median baseline LVEF of CHF pts was 60. Conclusion: Incorporation of B into anthracycline and taxane containing adjuvant therapy results in a significant but small increase in clinical CHF. The rate of clinical CHF is similar to that predicted by E2104 (2.5–2.9%) and reported In the FDA label for anthracycline pre-treated pts(3.8%). No unexpected toxicities were encountered. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-17-01.

Abstract Background: In AI refractory MBC, TAM anti-tumor activity is limited (median PFS 4.5 months). In patients (pts) receiving TAM in the adjuvant and metastatic setting, breast cancer recurrence has been shown to differ based upon CYP2D6 genotype and Endx exposure. In collaboration with NCI, Z-Endx (NSC #750393) was synthesized and preclinical pharmacology studies demonstrated that oral Z- Endx resulted in > 20 fold Endx exposure compared to an equivalent dose of TAM and significantly greater anti-tumor activity than TAM in AI sensitive and resistant MCF7 xenografts. We conducted a phase I study of Z-Endx in women with ER+, AI refractory MBC to identify dose-limiting toxicities (DLT), a maximum tolerated dose (MTD) and a dose associated with steady state concentrations (Css) of ≥ 2 uM, based on the IC50 of recently identified Endx substrates: PKC and PI3K. Methods: Pts were enrolled to an accelerated titration schedule (2 pts/dose level) until moderate toxicity or DLT, and then to a 3+3 design. Z-Endx was administered orally once daily (28 day cycle). Eye exams were performed at baseline, end of cycle 2, and after 6 cycles. PK was performed on days 1-2, 3, 7, 14, and 28, and prior to subsequent cycles. Results: 23 women with AI refractory MBC (median 56 yrs, range 41-83) received Z-Endx once daily encompassing 7 dose levels (Table 1). The median number of prior chemotherapies and hormonal therapies in the metastatic setting were 2 and 2, respectively. Dose escalation continues at 160 mg/day and the MTD has yet to be determined. Cmax and AUC increased in a dose-dependent manner. A 20 and 100 mg/day dose yields Css of 0.39 and 2.48 uM, respectively. Significant anti-tumor activity was observed including 1 pt (100 mg/day) with a PR lasting 225 days; 1 pt (80 mg/day) with a 30% reduction in tumor size (PFS 169 days) and 2 pts (60 and 80 mg/day) with stable disease for >270 days. No eye toxicity was observed. Conclusions: In women with AI refractory MBC, the MTD of Z-Endx HCl has not been determined but Endx Css concentrations of > 2 uM and substantial anti-tumor activity has been observed. Following completion of the 160 mg/day dose, expansion at 20 and 100 mg/day will commence to perform translational studies and further characterize Endx pk. A randomized phase II examining two different doses of Z-Endx is planned in AI refractory MBC. Supported in part by CA 133049, CA69912, CA15083, CA116201, and CA15083. Table 1Dose Level (mg/day)Number of Treatment CyclesModerate or Severe Toxicities ReportedTumor ResponseProgression-free Survival (days)28 day Z-Endx Css (uM) 20 (n = 2)2; 3Gr 2 hot flashes (1 pt)----60; 850.39 40 (n = 2)2; 6noneStable (1 pt)61; 1670.66 60 (n = 6)1; 2; 2; 5; 8; 14Gr 4 Triglycerides (1 pt);Gr 3 thromboembolic event (1 pt); Gr 2 hot flashes, anemia, and hypoalbuminemia (1 pt)Stable (3 pts)125+; 56; 57; 132; 232; 4331.01 80 (n = 3)4; 6; 10Gr 2 hot flashesStable (3 pts)113; 169; 2961.61 100 (n = 3)1; 2; 8Gr 2 nausea (1 pt); Gr 2 irritability (1 pt)PR (1 pt)30; 56; 2252.48 120 (n = 3)1; 2; 4Gr 2 hypersomnia, paresthesia, and peripheral sensory neuropathy (1 pt)—39; 54; 1082.18 * Bold face toxicities occurred during cycle 1 Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD3-4.

Abstract Background: Based upon the association between pathologic response and disease free survival, the neoadjuvant setting is increasingly being used for drug development. NGS has identified unique and recurrent genetic alterations in breast cancer (BC) that are potentially targetable; however, the clinical implications are mostly unknown. We developed a prospective neoadjuvant study (BEAUTY) in high risk BC patients (pts) using weekly T followed by anthracycline-based chemo wherein percutaneous tumor biopsies (PTB) are obtained before/during/after chemo for NGS and PDX. Our goal is to identify novel biomarkers/pathways and develop PDX to test new therapeutic approaches. Methods: Pts underwent PTB at baseline and after 12 wks of T. Response to T was defined based upon 12 week Ki-67: responder (<15%) vs non-responder (≥15%). Pts with histologic response and absence of invasive BC at 12 wks were classified as responders. NGS was performed using PTB/blood DNA (exome) and PTB (RNA seq). MRI response was classified using RECIST criteria. NGS data were used to identify somatic copy number variants (cnvs) and expressed single nucleotide variants (eSNVs). Non-SCID mice (estrogen supplemented) were implanted ≤ 30 minutes with PTB samples. Results: Of the first 78 pts, 44 have completed T. Here we focus on 18 pts with either triple negative or luminal B BC. Clinical characteristics according to Ki-67 response are shown in Table 1. Comparison of genomic alterations in BEAUTY pts with TCGA identified a greater overlap with copy number gains (73%) compared to deletions (40%), along with similar observations of mutations in TP53, PTEN, RYR2, and AKT1 genes. Association analysis of CNVs and eSNVs between responders/non-responders identified 33 genes (predominantly located in chromosomes 1, 8, 13) and 580 eSNVs (corresponding to 497 genes) with a p < 0.05. Differential gene expression (DGE) analysis of responders/non-responders identified 198 genes with a p-value < 0.05. Integrated analysis of 539 genes (CNVs, eSNVs and DGE) identified pathways such as TGF-beta, Jak-Stat, WNT and NOTCH signalling. PDX take rate was 44% [triple negative (6/10); Luminal B (2/8)]. PDX growth rate was significantly associated with clinical baseline Ki-67 (p = 0.00014). Conclusion: This is the first prospective study to demonstrate the feasibility of using PTB to obtain both NGS data and PDX in the neoadjuvant setting. PDX take rate is associated with BC subtype and baseline Ki-67. Studies are ongoing to 1) validate genes/pathways associated with treatment response in subsequent BEAUTY pts; 2) genomically characterize and assess PDX in vivo response to T and 3) Use NGS data to prioritize new drugs/drug combinations in PDX. Funded by Mayo Clinic Center for Individualized Medicine and MC Cancer Center. Clinical CharacteristicsOverallResponders: 12 week Ki-67 < 15% (n = 9)Non-Responders: 12 week Ki-67 ≥ 15% (n = 9)Median Age495345T stage T2/T314 (78%)7 (78%)7 (78%)Node Positive8 (44%)4 (44%)4 (44%)Triple negative10 (56%)6 (67%)4 (44%)Luminal B8 (44%)3 (33%)5 (56%)Ki-67 after 12 Weeks of T Median 5% (0-11%)Median 35% (17-60%)Complete/Partial MRI Response after T 6 (67%)2 (22%) Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-08-10.

Abstract Purpose: This phase I, multicenter, open-label, single-arm, dose-escalation, and dose-expansion study evaluated the safety, tolerability, and antitumor activity of MEDI-573 in adults with advanced solid tumors refractory to standard therapy or for which no standard therapy exists. Experimental Design: Patients received MEDI-573 in 1 of 5 cohorts (0.5, 1.5, 5, 10, or 15 mg/kg) dosed weekly or 1 of 2 cohorts (30 or 45 mg/kg) dosed every 3 weeks. Primary end points included the MEDI-573 safety profile, maximum tolerated dose (MTD), and optimal biologic dose (OBD). Secondary end points included MEDI-573 pharmacokinetics (PK), pharmacodynamics, immunogenicity, and antitumor activity. Results: In total, 43 patients (20 with urothelial cancer) received MEDI-573. No dose-limiting toxicities were identified, and only 1 patient experienced hyperglycemia related to treatment. Elevations in levels of insulin and/or growth hormone were not observed. Adverse events observed in >10% of patients included fatigue, anorexia, nausea, diarrhea, and anemia. PK evaluation demonstrated that levels of MEDI-573 increased with dose at all dose levels tested. At doses >5 mg/kg, circulating levels of insulin-like growth factor (IGF)-I and IGFII were fully suppressed. Of 39 patients evaluable for response, none experienced partial or complete response and 13 had stable disease as best response. Conclusions: The MTD of MEDI-573 was not reached. The OBD was 5 mg/kg weekly or 30 or 45 mg/kg every 3 weeks. MEDI-573 showed preliminary antitumor activity in a heavily pretreated population and had a favorable tolerability profile, with no notable perturbations in metabolic homeostasis. Clin Cancer Res; 20(18); 4747–57. ©2014 AACR.

Abstract Purpose: This phase I, open-label, uncontrolled, ascending-dose study explored the safety, maximum tolerated dose (MTD), pharmacokinetics, and pharmacology of the TLR8 agonist VTX-2337 in subjects with advanced solid tumors or lymphoma. Experimental Design: VTX-2337 doses (0.1–3.9 mg/m2) were administered subcutaneously on days 1, 8, and 15 of each 28-day cycle. Safety/tolerability assessments included adverse events (AE); physical, ophthalmologic, and laboratory evaluations; and electrocardiograms. Dose-limiting toxicities (DLT) were evaluated during the first cycle. Pharmacokinetics were evaluated after the first dose. Plasma samples were quantitatively assessed for chemokines, cytokines, and other inflammatory mediators. Antitumor activity was assessed. Results: Thirty-three subjects were enrolled in 8 cohorts and received an average of 2 treatment cycles (range, 1–8 cycles). Most AEs were grades 1 to 2; the most common drug-related AEs were injection site reactions, chills, pyrexia, and influenza-like illness. One DLT was reported: grade 3 hypotension (3.9 mg/m2). The MTD was considered the highest dose administered. Peak drug plasma levels and total systemic exposure were generally dose proportional. At doses ≥0.4 mg/m2, increases above baseline levels were observed for plasma levels of G-CSF, monocyte chemoattractant protein-1, macrophage inflammatory protein-1β, and TNFα. Eight subjects (24.2%) had a best response of stable disease (median duration, 54.5 days). Conclusions: VTX-2337 is clinically well tolerated and biologically active with a predictable pharmacokinetic profile. Suitable doses for testing in combination studies were identified. Phase II placebo-controlled studies of VTX-2337 in combination with doxorubicin in ovarian cancer, and in combination with platinum chemotherapy, 5 FU, and cetuximab in head and neck cancer have been initiated (NCT #01666444 and NCT#01836029). Clin Cancer Res; 20(14); 3683–91. ©2014 AACR.

Abstract Purpose: We hypothesized that vertical blockade of VEGF signaling by combining bevacizumab with sorafenib in patients with recurrent glioblastoma would result in a synergistic therapeutic effect. We also investigated whether VEGF, VEGFR2 and hypoxia-inducible factor-1α single-nucleotide polymorphisms (SNP), circulating biomarkers of angiogenesis, and MRI markers such as apparent diffusion coefficient (ADC) are correlated with treatment efficacy and/or toxicity. Experimental Design: Patients received bevacizumab (5 mg/kg every 2 weeks) with sorafenib (200 mg twice a day, weekly, days 1–5; group A). Due to toxicity, the starting sorafenib dose was subsequently modified to 200 mg every day (group B). Results: Fifty-four patients were enrolled: 19 patients in group A and 35 in group B. Objective response rate was 18.5% with median duration of 6.7 months (range 0.5–24.1 months). Six-month progression-free survival (PFS6) was 20.4% (11/54), and median overall survival (OS) was 5.6 months [95% confidence interval (CI), 4.7–8.2]; outcome was similar between the two dose groups. We identified SNPs in the VEGF and VEGFR2 promoter regions, which were associated with PFS6 (P < 0.022). Among molecular markers of angiogenesis, a higher log2 baseline level of stromal cell–derived factor-1 was associated with PFS6 success (P = 0.04). Circulating endothelial cells decreased during treatment with subsequent increase at disease progression (P = 0.022). Imaging analysis showed a trend associating ADC-L with poor outcome. Conclusions: The bevacizumab/sorafenib combination did not improve outcome of patients with recurrent glioblastoma versus historic bevacizumab-treated controls. Biologic markers of response and resistance to bevacizumab in gliomas were identified which merit prospective validation. Clin Cancer Res; 19(17); 4816–23. ©2013 AACR.