Yuying C. Hwang

Safety, Pharmacokinetics, and Antitumor Activity of AMG 386, a Selective Angiopoietin Inhibitor, in Adult Patients With Advanced Solid Tumors

PURPOSE AMG 386 is an investigational peptide-Fc fusion protein (ie, peptibody) that inhibits angiogenesis by preventing the interaction of angiopoietin-1 and angiopoietin-2 with their receptor, Tie2. This first-in-human study evaluated the safety, pharmacokinetics (PK), pharmacodynamics, and antitumor activity of AMG 386 in adults with advanced solid tumors. PATIENTS AND METHODS Patients in sequential cohorts received weekly intravenous AMG 386 doses of 0.3, 1, 3, 10, or 30 mg/kg. Results Thirty-two patients were enrolled on the study and received AMG 386. One occurrence of dose-limiting toxicity was seen at 30 mg/kg: respiratory arrest, which likely was caused by tumor burden that was possibly related to AMG 386. The most common toxicities were fatigue and peripheral edema. Proteinuria (n = 11) was observed without clinical sequelae. Only four patients (12%) experienced treatment-related toxicities greater than grade 1. A maximum-tolerated dose was not reached. PK was dose-linear and the mean terminal-phase elimination half-life values ranged from 3.1 to 6.3 days. Serum AMG 386 levels appeared to reach steady-state after four weekly doses, and there was minimal accumulation. No anti-AMG 386 neutralizing antibodies were detected. Reductions in volume transfer constant (K(trans); measured by dynamic contrast-enhanced magnetic resonance imaging) were observed in 10 patients (13 lesions) 48 hours to 8 weeks after treatment. One patient with refractory ovarian cancer achieved a confirmed partial response (ie, 32.5% reduction by Response Evaluation Criteria in Solid Tumors) and withdrew from the study with a partial response after 156 weeks of treatment; four patients experienced stable disease for at least 16 weeks. CONCLUSION Weekly AMG 386 appeared well tolerated, and its safety profile appeared distinct from that of vascular endothelial growth factor-axis inhibitors. AMG 386 also appeared to impact tumor vascularity and showed antitumor activity in this patient population.

A First-in-Human Study of Conatumumab in Adult Patients with Advanced Solid Tumors

Purpose: To determine the safety, tolerability, pharmacokinetics, and maximum tolerated dose (MTD) of conatumumab, an investigational, fully human monoclonal agonist antibody against human death receptor 5, in patients with advanced solid tumors. Experimental Design: In the dose-escalation phase, patients received escalating intravenous doses of conatumumab (0.3, 1, 3, 10, or 20 mg/kg, 3–9 per cohort) every 2 weeks. In the dose-expansion phase, 10 patients with colorectal cancer (CRC) and 7 with non–small cell lung cancer (NSCLC) received 20 mg/kg of conatumumab every 2 weeks. Results: Thirty-seven patients received 1 or more doses of conatumumab. Conatumumab seemed to be well tolerated; there were no dose-limiting toxicities. Of adverse events possibly related to treatment, only 3 patients (8%) had a grade 3 event (fatigue and/or elevated lipase), and no anticonatumumab antibodies were detected. An MTD was not reached. Conatumumab exhibited dose linear kinetics from 3 to 20 mg/kg, with a mean terminal half-life of 13 to 19 days. One patient with NSCLC (0.3 mg/kg) had a confirmed partial response (PR) at week 32 (38% reduction in tumor size), with further reduction (48%) by week 96; this patient remains on conatumumab after 4.2 years with a sustained PR. Fourteen patients had a best response of stable disease, 2 for 32 weeks or more. One patient with CRC (0.3 mg/kg) and stable disease for 24 weeks had a 24% reduction in tumor size by RECIST (Response Evaluation Criteria in Solid Tumors) and a 35% reduction in the sum of standardized uptake values of all lesions measured by [18F]fluorodeoxyglucose positron emission tomographic scan. Changes in tumor levels of activated caspase-3 did not appear to be associated with tumor response. Conclusions: Conatumumab can be administered safely up to the target dose of 20 mg/kg every 2 weeks. Clin Cancer Res; 16(23); 5883–91. ©2010 AACR.

Safety and pharmacokinetics of ganitumab (AMG 479) combined with sorafenib, panitumumab, erlotinib, or gemcitabine in patients with advanced solid tumors

Purpose: This phase 1b dose-escalation study assessed safety, tolerability, and pharmacokinetics of ganitumab, a fully human monoclonal antibody against the insulin-like growth factor 1 (IGF1) receptor, combined with targeted agents or cytotoxic chemotherapy in patients with advanced solid tumors. Experimental Design: Patients with treatment-refractory advanced solid tumors were sequentially enrolled at 2 ganitumab dose levels (6 or 12 mg/kg i.v. every 2 weeks) combined with either sorafenib 400 mg twice daily, panitumumab 6 mg/kg every 2 weeks, erlotinib 150 mg once daily, or gemcitabine 1,000 mg/m2 on days 1, 8, and 15 of each 4-week cycle. The primary end points were safety and pharmacokinetics of ganitumab. Results: Ganitumab up to 12 mg/kg appeared well tolerated combined with sorafenib, panitumumab, erlotinib, or gemcitabine. Treatment-emergent adverse events were generally mild and included fatigue, nausea, vomiting, and chills. Three patients had dose-limiting toxicities: grade 3 hyperglycemia (ganitumab 6 mg/kg and panitumumab), grade 4 neutropenia (ganitumab 6 mg/kg and gemcitabine), and grade 4 thrombocytopenia (ganitumab 12 mg/kg and erlotinib). Ganitumab-binding and panitumumab-binding antibodies were detected in 5 and 2 patients, respectively; neutralizing antibodies were not detected. The pharmacokinetics of ganitumab and each cotherapy did not appear affected by coadministration. Circulating total IGF1 and IGF binding protein 3 increased from baseline following treatment. Four patients (9%) had partial responses. Conclusions: Ganitumab up to 12 mg/kg was well tolerated, without adverse effects on pharmacokinetics in combination with either sorafenib, panitumumab, erlotinib, or gemcitabine. Ganitumab is currently under investigation in combination with some of these and other agents. Clin Cancer Res; 18(12); 3414–27. ©2012 AACR.

A Phase I, First-in-Human Study of AMG 780, an Angiopoietin-1 and -2 Inhibitor, in Patients with Advanced Solid Tumors.

Purpose: To assess the toxicity, pharmacokinetics, tumor vascular response, tumor response, and pharmacodynamics of AMG 780, a mAb designed to inhibit the interaction between angiopoietin-1 and -2 and the Tie2 receptor. Experimental Design: This was a phase I dose-escalation study of patients with advanced solid tumors refractory to standard treatment without previous antiangiogenic treatment. AMG 780 was administered by intravenous infusion every 2 weeks in doses from 0.1 to 30 mg/kg. The primary endpoints were incidences of dose-limiting toxicity (DLT) and adverse events (AE), and pharmacokinetics. Secondary endpoints included tumor response, changes in tumor volume and vascularity, and anti-AMG 780 antibody formation. Results: Forty-five patients were enrolled across nine dose cohorts. Three patients had DLTs (0.6, 10, and 30 mg/kg), none of which prevented dose escalation. At 30 mg/kg, no MTD was reached. Pharmacokinetics of AMG 780 were dose proportional; median terminal elimination half-life was 8 to 13 days. No anti-AMG 780 antibodies were detected. At week 5, 6 of 16 evaluable patients had a >20% decrease in volume transfer constant (Ktrans), suggesting reduced capillary blood flow/permeability. The most frequent AEs were hypoalbuminemia (33%), peripheral edema (29%), decreased appetite (27%), and fatigue (27%). Among 35 evaluable patients, none had an objective response; 8 achieved stable disease. Conclusions: AMG 780 could be administered at doses up to 30 mg/kg every 2 weeks in patients with advanced solid tumors. AMG 780 treatment resulted in tumor vascular effects in some patients. AEs were in line with toxicity associated with antiangiopoietin treatment. Clin Cancer Res; 22(18); 4574–84. ©2016 AACR.

First-in-human study of AMG 208, an oral MET inhibitor, in adult patients (pts) with advanced solid tumors.

41 Background: AMG 208 is a small molecule MET inhibitor that suppresses proliferation and induces apoptosis in human tumor xenografts. This first-in-human study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of AMG 208. We report data from the dose escalation part of the study. METHODS Key eligibility criteria: ≥ 18 yr, advanced solid tumors, ECOG ≤ 2, and evaluable/measurable disease. Using a modified Fibonacci design, 3-9 pts were enrolled into 1 of 7 sequential dose cohorts (25, 50, 100, 150, 200, 300, and 400 mg) of AMG 208. Pts received AMG 208 orally on days 1 and 4-28 once daily. If no dose limiting toxicity (DLT) was seen on days 1-28, pts received AMG 208 once daily starting at day 36 provided pts showed no evident disease progression. In cohorts 1-3, a standard 3+3 design was followed. In cohorts 4-7, a modified 3+3+3 design was followed. RESULTS As of July 16 2012, 54 pts (25 mg [n=6], 50 mg [n=4], 100 mg [n=4], 150 mg [n=3], 200 mg [n=16], 300 mg [n=10], and 400 mg [n =11]) had received ≥ 1 dose of AMG 208. 67% were men; 19% had prostate cancer (PC). Median (range) age: 61 (39-80) yr. ECOG 0/1: 52%/48%. 6 DLTs were seen: a grade (G) 3 increased AST (200 mg), a G3 thrombocytopenia (200 mg), a G4 acute myocardial infarction (300 mg), a G3 prolonged QT (300 mg), and two G3 hypertensions (400 mg). The maximum tolerated dose was not reached. 83% of pts had tx-related adverse events (AE). Tx-related AE occurring in > 10 pts: fatigue (n=24), nausea (n=18), hypertension (n=12), and diarrhea (n=11). 24% of pts had grade ≥ 3 tx-related AE. AMG 208 was orally bioavailable with a 30-35 hr mean half-life in plasma. Exposure increased linearly with dose; accumulation at day 28 was 2.7-fold across cohorts. Of the 42 pts with available tumor response data for site reads, 1 had complete response on bone scan (PC 300 mg) while 2 had partial responses (PR; PC 400 mg and kidney cancer 200 mg; both had -33% tumor shrinkage), and 29 had stable disease (SD); 1 other PC pt had PR after data cutoff. Of the 35 pts with available tumor response data for central reads, 26 had SD. FLT and biomarker data will be presented. CONCLUSIONS AMG 208 up to 400 mg daily had manageable toxicities and showed evidence of antitumor activity, especially in prostate cancer. CLINICAL TRIAL INFORMATION NCT00813384.

Measurement of Tumor Blood Flow by Deuterium Nuclear Magnetic Resonance Spectroscopy: Application to Murine RIF-1 Tumor

Quantification of tumor blood flow is of importance both for proper evaluation of tumor growth and metabolism and for improvement of the effectiveness of various therapeutic modalities (e.g., heat, drugs, radiation, photodynamics, etc.). For example, the selective sensitization of tumors to hyperthermia is generally ascribed to the poor blood flow (and, thus, heat dissipation) of solid tumors relative to surrounding normal tissue. Under conditions of hyperglycemia, a state of potentially enhanced thermal sensitization, a flow reduction has been hypothesized to assist in a build up of acidic waste metabolites (i.e., lactic acid) leading to a decrease in tumor pH. Other modalities of therapy also depend on the character of tumor blood flow. The distribution and rate of blood flow in tumors have important implications for radiotherapy and chemotherapy. Ionizing irradiation preferentially kills those cells that contain substantial amounts of dissolved oxygen (i.e., that are well perfused), while anoxic or hypoxic tumor cells that are not fully oxygenated are relatively radiation-resistant. Enhancement of tumor blood flow is expected to improve tumor oxygenation and to increase the effectiveness of radiotherapy.