David Monteith

Therapeutic suppression of translation initiation factor eIF4E expression reduces tumor growth without toxicity

Expression of eukaryotic translation initiation factor 4E (eIF4E) is commonly elevated in human and experimental cancers, promoting angiogenesis and tumor growth. Elevated eIF4E levels selectively increase translation of growth factors important in malignancy (e.g., VEGF, cyclin D1) and is thereby an attractive anticancer therapeutic target. Yet to date, no eIF4E-specific therapy has been developed. Herein we report development of eIF4E-specific antisense oligonucleotides (ASOs) designed to have the necessary tissue stability and nuclease resistance required for systemic anticancer therapy. In mammalian cultured cells, these ASOs specifically targeted the eIF4E mRNA for destruction, repressing expression of eIF4E-regulated proteins (e.g., VEGF, cyclin D1, survivin, c-myc, Bcl-2), inducing apoptosis, and preventing endothelial cells from forming vessel-like structures. Most importantly, intravenous ASO administration selectively and significantly reduced eIF4E expression in human tumor xenografts, significantly suppressing tumor growth. Because these ASOs also target murine eIF4E, we assessed the impact of eIF4E reduction in normal tissues. Despite reducing eIF4E levels by 80% in mouse liver, eIF4E-specific ASO administration did not affect body weight, organ weight, or liver transaminase levels, thereby providing the first in vivo evidence that cancers may be more susceptible to eIF4E inhibition than normal tissues. These data have prompted eIF4E-specific ASO clinical trials for the treatment of human cancers.

In vitro assays and biomarkers for drug-induced phospholipidosis

Drug-induced phospholipidosis is the cytoplasmic accumulation of phospholipids as a result of xenobiotic exposure. This accumulation results in a unique histological effect in cells noted as electron-dense lamellar inclusions or whorls in the cytoplasm when observed with transmission electron microscopy. Electron microscopy has been the widely accepted standard for classification of the phospholipidosis effect. Molecules that have been prone to induce such an effect are made up of a lipophilic region and a positively charged region. Phospholipidosis has most commonly been associated with drugs that are cationic, amphiphilic drugs and can occur in a variety of tissues. Although phospholipidosis is not considered adverse in isolation, depending on the tissue affected or the occasional circumstance of concurrent toxicity, phospholipidosis can be perplexing if identified in early drug development. In most circumstances, characterisation of the effect with in vivo studies allows for determination of exposure and the magnitude of the effect. On occasion in drug development, there may be an interest to screen early stage compounds to minimise phospholipidosis. In such circumstances, in silico and in vitro assays can be employed in a strategy with in vivo assessments. In addition, there may be an interest to monitor for the potential development of phospholipidosis in longer-term animal studies. In such cases, biomarker approaches could be used. The challenge in the overall assessment of phospholipidosis remains the question of the possible relevance to any toxicity, and, therefore, any screening approach, while assessing the potential to induce phospholipidosis, must be considered in relation to prediction of findings in vivo. The status of current assays and biomarkers is presented with strategies for screening.

Translational Pharmacodynamics of Calcitonin Gene-Related Peptide Monoclonal Antibody LY2951742 in a Capsaicin-Induced Dermal Blood Flow Model

LY2951742, a monoclonal antibody targeting calcitonin gene-related peptide (CGRP), is being developed for migraine prevention and osteoarthritis pain. To support the clinical development of LY2951742, capsaicin-induced dermal blood flow (DBF) was used as a target engagement biomarker to assess CGRP activity in nonhuman primates and healthy volunteers. Inhibition of capsaicin-induced DBF in nonhuman primates, measured with laser Doppler imaging, was dose dependent and sustained for at least 29 days after a single intravenous injection of the CGRP antibody. This information was used to generate a pharmacokinetic/pharmacodynamic model, which correctly predicted inhibition of capsaicin-induced DBF in humans starting at a single subcutaneous 5-mg dose. As expected, the degree of inhibition in capsaicin-induced DBF increased with higher LY2951742 plasma concentrations. Utilization of this pharmacodynamic biomarker with pharmacokinetic data collected in phase I studies provided the dose-response relationship that assisted in dose selection for the phase II clinical development of LY2951742.

Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of the CGRP Binding Monoclonal Antibody LY2951742 (Galcanezumab) in Healthy Volunteers

Background: Calcitonin gene-related peptide (CGRP) is pivotal in the pathophysiology of migraine headaches and represents a promising target for migraine treatment. The humanized monoclonal antibody galcanezumab (LY2951742) binds to CGRP and may be effective in migraine prophylaxis. Objectives: The primary objective was to evaluate the safety and tolerability of single and multiple doses of galcanezumab in humans. Secondary objectives included assessing the pharmacokinetics and evaluating target engagement. Methods: A double-blind, randomized, placebo-controlled study (NCT 01337596) with single escalating and multiple subcutaneous (SC) doses of galcanezumab was performed in healthy male volunteers. Single doses of 1, 5, 25, 75, 200, and 600 mg of galcanezumab (n = 7/dose) or placebo (n = 2/dose) were injected SC in six consecutive cohorts of nine subjects each. One cohort of nine subjects received multiple (4) 150 mg doses of galcanezumab or placebo every other week. Target engagement was evaluated by measuring inhibition of capsaicin-induced increase in dermal blood flow (DBF). Findings: Sixty-three subjects were randomized and included in the safety analyses. Galcanezumab was well tolerated in single doses (1–600 mg SC) and consecutive doses (150 mg SC). There was no dose-dependent difference in type or frequency of treatment-emergent adverse events, and no clinically meaningful difference when compared with placebo. Pharmacokinetics were linear. Galcanezumab induced a robust, dose-dependent, and durable inhibition of capsaicin-induced increase in DBF, supporting the continued clinical development of galcanezumab for prophylaxis in migraine patients.

Abstract CT215: A phase I trial of LY2874455, a fibroblast growth factor receptor inhibitor, in patients with advanced cance

Background: Deregulation of the fibroblast growth factor (FGF) and the FGF receptor (FGFR) pathway is implicated in several human cancers (1, 2). Inhibition of the FGF pathway has led to the attenuation of tumor growth in preclinical xenograft models. LY2874455 is a novel class of FGFR inhibitor with potent biochemical/cellular inhibitory activities and in vivo target inhibition in xenograft models (3). Methods & Objectives: This phase I multicenter nonrandomized, open-label study of oral LY2874455 consisted of dose escalation (part A) and dose expansion (part B). The primary objective was to determine the recommended phase II dose and schedule. Secondary objectives included safety, pharmacokinetics, and pharmacodynamic response. Results: Thirty-six patients were treated with escalating doses of oral LY2784455. Doses ranged from 2-10 mg once daily (QD) or 8-24 mg twice daily (BID). Patients were mostly male (69%) and ages ranged from 23-78. Nineteen patients were white and 17 were Asian. The most common type of treatment-emergent adverse events possibly related to study drug was gastrointestinal (n=2, n=1 Grade 3/4). One patient experienced grade 2 thrombosis, which was possibly related to study drug. There were no reported dose limiting toxicities. Pharmacokinetic analyses revealed the half-life was relatively short and without drug accumulation from a single dose; thus, a twice daily regimen was evaluated. Exposure increase was near proportional with dose. Plasma AUC increased 1.1 to 2.3 fold with twice daily administration from day 1 to 28. Serum phosphorus levels increased following dose with administration of ≥10 mg of LY2874455 but were adequately controlled by phosphate-binding agents. This result is consistent with inhibition of the FGF Receptor. Conclusions: The 16 mg BID dose was selected for the starting dose in Part B based on the tolerability observed and in consideration of the tolerability of this dose with chronic administration. Recommended phase II dose was not yet established awaiting data from part B (ongoing). References: 1. Falvella FS, Frullanti E, Galvan A, Spinola M, Noci S, De Cecco L, et al. FGFR4 Gly388Arg polymorphism may affect the clinical stage of patients with lung cancer by modulating the transcriptional profile of normal lung. International journal of cancer Journal international du cancer. 2009;124:2880-5. 2. Hattori Y, Itoh H, Uchino S, Hosokawa K, Ochiai A, Ino Y, et al. Immunohistochemical detection of K-sam protein in stomach cancer. Clinical cancer research 1996;2:1373-81. 3. Zhao G, Li WY, Chen D, Henry JR, Li HY, Chen Z, et al. A novel, selective inhibitor of fibroblast growth factor receptors that shows a potent broad spectrum of antitumor activity in several tumor xenograft models. Molecular cancer therapeutics. 2011;10:2200-10. Citation Format: Jeanne Tie, Yung-Jue Bang, Young Suk Park, Yoon-Koo Kang, David Monteith, Kimberly Hartsock, Donald E. Thornton, Michael Michael. A phase I trial of LY2874455, a fibroblast growth factor receptor inhibitor, in patients with advanced cance. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr CT215. doi:10.1158/1538-7445.AM2014-CT215

Abstract CT058: Phase I study of LY2874455, a fibroblast growth factor (FGF) receptor inhibitor, in patients with advanced cancer

Background: The fibroblast growth factor (FGF) and FGF receptor pathway has been implicated in several cancers. Inhibition of this pathway has led to the attenuation of tumor growth in preclinical models1. This phase I, first in human dose (FIH) study evaluated safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and efficacy of LY2874455, an oral FGF receptor inhibitor. Methods: This study had 2 open-label parts. Part A: standard 3+3 patient dose escalation study, identified 16 mg BID as the recommended dose2. Part B: dose expansion study, evaluated 16 mg BID dose in patients (pts) with pretreated advanced gastric cancer (GC) or non-small cell lung carcinoma (NSCLC), who also had ECOG performance status 0-2 and adequate organ function. Treatment continued until disease progression or intolerability. We report here results from Part B of the study. Results: Overall 27 pts in the NSCLC cohort and 31 pts in the GC cohort were treated. Median age was 58.5 years: majority of pts were Asian (89.7%). Pts had received a median of 4 previous lines of chemotherapy. FGFR1 amplification status in the NSCLC group: 29.6% were negative, 7.4% were positive, and status was unknown in 63.0%. For GC pts: 80.6% negative for FGFR2 amplification, 6.5% positive, and status unknown in 12.9%. Both cohorts each received a median of 2 cycles. All 58 pts experienced at least 1 treatment emergent adverse event (TEAE) possibly related to study drug, with 39 pts (67.2%) experiencing at least 1 Grade 3 or 4 TEAE possibly related to study drug. The most common drug-related AEs included: hyperphosphatemia (79.3%), diarrhea (77.6%), anorexia (72.4%), and fatigue (51.7%). Eighteen pts (31.0%) experienced at least 1 serious adverse event (SAE), and 9 pts had SAE possibly related to study drug related. SAEs possibly related to study drug were: fatigue (n = 4), anorexia (n = 3), heamoptysis, central serous retinopathy, keratoconjunctivitis sicca, diarrhea, and hyponatremia. Eleven pts discontinued due to AE or SAE. In the GC cohort, 1 patient, who was FGFR2 amplification negative, had a partial response, and 6 FGFR2 negative pts had stable disease (SD), with 1 patient on treatment for 9 cycles. None of the NSCLC pts responded, but 4 pts had SD (FGFR1 positive n = 2; FGFR1 negative n = 2). Conclusion: Treatment with LY2874455 had a manageable toxicity profile, and preliminary findings suggest anti-tumor activity in gastric cancer. 1. Hattori Y, Itoh H, Uchino S, Hosokawa K, Ochiai A, Ino Y, et al. Immunohistochemical detection of K-sam protein in stomach cancer. Clinical cancer research : an official journal of the American Association for Cancer Research. 1996;2:1373-81. 2. Tie, J., et al. “A phase I trial of LY2874455, a fibroblast growth factor receptor inhibitor, in patients with advanced cancer.” Proceedings of the 105th annual meeting of the American Association for Cancer Research 2014;74(19 Suppl):Abstract nr CT215. Citation Format: Jeanne Tie, Yung-Jue Bang, Young Suk Park, Yoon-Koo Kang, David Monteith, Kimberly Hartsock, Oday Hamid, Donald E. Thornton, Michael Michael. Phase I study of LY2874455, a fibroblast growth factor (FGF) receptor inhibitor, in patients with advanced cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr CT058.