A Phase I Clinical Trial of Systemically Delivered NEMO Binding Domain Peptide in Dogs with Spontaneous Activated B-Cell like Diffuse Large B-Cell Lymphoma

Abstract

Activated B-Cell (ABC) Diffuse Large B-Cell Lymphoma (DLBCL) is a common, aggressive and poorly chemoresponsive subtype of DLBCL, characterized by constitutive canonical NF-κB signaling. Inhibition of NF-κB signaling leads to apoptosis of ABC-DLBCL cell lines, suggesting targeted disruption of this pathway may have therapeutic relevance. The selective IKK inhibitor, NEMO Binding Domain (NBD) peptide effectively blocks constitutive NF-κB activity and induces apoptosis in ABC-DLBCL cells in vitro. Here we used a comparative approach to determine the safety and efficacy of systemic NBD peptide to inhibit constitutive NF-κB signaling in privately owned dogs with spontaneous newly diagnosed or relapsed ABC-like DLBCL. Malignant lymph nodes biopsies were taken before and twenty-four hours after peptide administration to determine biological effects. Intravenous administration of <2 mg/kg NBD peptide was safe and inhibited constitutive canonical NF-κB activity in 6/10 dogs. Reductions in mitotic index and Cyclin D expression also occurred in a subset of dogs 24 hours post peptide and in 3 dogs marked, therapeutically beneficial histopathological changes were identified. Mild, grade 1 toxicities were noted in 3 dogs at the time of peptide administration and one dog developed transient subclinical hepatopathy. Long term toxicities were not identified. Pharmacokinetic data suggested rapid uptake of peptide into tissues. No significant hematological or biochemical toxicities were identified. Overall the results from this phase I study indicate that systemic administration of NBD peptide is safe and effectively blocks constitutive NF-κB signaling and reduces malignant B cell proliferation in a subset of dogs with ABC-like DLBCL. These results have potential translational relevance for human ABC-DLBCL.

Enhancing the Cell Permeability and Metabolic Stability of Peptidyl Drugs by Reversible Bicyclization

“…HEK293 cells transfected with a luciferase reporter gene under the control of NF-κB were first treated with varying concentrations of a peptide for 1 h and then TNFα. [9,10e] In the absence of any inhibitory peptide, treatment with 5 ng/mL TNFα increased the luciferase activity from a basal level of 177 arbitrary units (AU) to 715 AU (data not shown). Peptide 4 reduced the TNFα-induced luciferase activity in a dose-dependent manner, with an IC 50 value of ~20 μM (Figure 1c).…”

“…[9] In several pre-clinical studies, Antp-NBD demonstrated in vivo efficacy for treating Duchenne muscular dystrophy and large B-cell lymphoma in mouse and canine models. [10] However, to achieve clinical utility, Antp-NBD would benefit significantly from improvements in its NEMO-binding affinity, metabolic stability, and cell-permeability.…”

“…Despite of its in vivo efficacy, the linear Antp-NBD peptide has poor pharmacokinetics, due to rapid proteolytic degradation in serum (t 1/2 ~15 min). [10] We envisioned that conversion of Antp-NBD into a conformationally constrained bicyclic structure would substantially increase its proteolytic stability. The CPP motif RRRRΦF was fused to the N-terminus of NBD, TALDWSWLQT, and the N- and C-terminal threonine residues were replaced with two cysteines (Table 1, peptide 4 , Figure S2 for detailed structure).…”

CAR T Cell Immunotherapy in Human and Veterinary Oncology: Changing the Odds Against Hematological Malignancies

“…In a separate phase 1 clinical trial, these same investigators showed that NBD peptide administered intravenously is safe and effective at inhibiting constitutive NF-κB activity in a subset of dogs with lymphoma (85).…”

Cell-Permeable Bicyclic Peptidyl Inhibitors against NEMO-IκB Kinase Interaction Directly from a Combinatorial Library

“…33 Antp-NBD has been used as an NF- κ B inhibitor in numerous in vitro and in vivo studies. For example, it has demonstrated in vivo efficacy for treatment of acute lung injury, 34 Duchenne muscular dystrophy, 35,36 and large B-cell lymphoma 37 in murine and canine models. However, its low potency and poor pharmacokinetics (e.g., serum half-life of ~15 min) prevented further clinical development.…”