Search

Protein arginine methyltransferase 5 (PRMT5), a type II methyltransferase, is responsible for symmetric arginine di-methylation of multiple cellular proteins involved in the regulation of cellular transcription. PRMT5 is involved in cellular processes such as survival, proliferation, and apoptosis, and an elevated tumor PRMT5 protein level has recently been correlated with poor survival of cancer patients. JNJ-64619178, a selective PRMT5 inhibitor, showed inhibition of cellular growth in several cell lines representing multiple cancer histologies in vitro. From this, a broad selection of xenograft models was chosen to demonstrate potent anti-tumor efficacy. Xenograft models representing small cell lung cancer (SCLC), non-small cell lung cancer (NSCLC), acute myeloid leukemia (AML), and non-Hodgkin lymphoma were chosen to demonstrate anti-tumor efficacy. Biologically significant tumor growth inhibition up to 99% was observed in both solid and hematological xenograft models, including an aggressive disseminated model of AML, with oral doses of 1 to 10 mg/kg, once daily. Importantly, continued inhibition of tumor growth was observed for several weeks following dosing cessation. Dosing of JNJ-64619178 results in inhibition of Sym-Arg di-methylation of SMD1/3 proteins, core components of the spliceosome in the tumor, and general Sym-Arg di-methylation of serum proteins. These serve as pharmacodynamic markers of PRMT5 inhibition in xenograft models. Potent and prolonged inhibition of SMD1/3 di-methylation was observed in the SCLC model, during and after the dosing period. This has led to the exploration of alternative dosing regimens preclinically. PRMT5 inhibitor JNJ-64619178 is currently being investigated in a Phase I clinical trial, based on its high selectivity and potency, favorable pharmacokinetics and safety properties, and strong preclinical efficacy and pharmacodynamic data. Citation Format: Hillary J. Millar, Dirk Brehmer, Tinne Verhulst, Nahor Haddish-Berhane, Tony Greway, Dana Gaffney, An Boeckx, Erika Van Heerde, Thomas Nys, Joseph Portale, Ulrike Philippar, Tongfei Wu, Sylvie Laquerre, Kathryn Packman. In vivo efficacy and pharmacodynamic modulation of JNJ-64619178, a selective PRMT5 inhibitor, in human lung and hematologic preclinical models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 950.

Protein arginine methyltransferase 5 (PRMT5) is an epigenetic enzyme with oncogenic properties. JNJ-64619178 (JNJ178) is a potent, selective, structurally unique PRMT5 inhibitor with good preclinical efficacy in inhibiting the growth of hematologic and solid tumor cell lines. Toxicology studies showed that JNJ178 decreased reticulocytes and neutrophils in rats and dogs. The objectives of translational modeling and simulation were to understand the exposure-response relationship of both safety and efficacy and provide guidance to the first-in-human clinical development of JNJ178. Experimental data for the PK/PD (Pharmacokinetics/Pharmacodynamics) modeling included: plasma concentration after single dose of JNJ178 in non-tumor bearing mice, plasma concentration and PD markers of dimethylation of arginine (%SDMA in plasma and %SMD1/3-Me2 in tumor, respectively) after multiple doses (1 to 10 mg/kg) QD (once daily) of JNJ178 in H1048 (human small cell lung carcinoma) xenografts, and tumor volume in four xenograft mouse models (A427, human lung carcinoma; H441, human lung adenocarcinoma; H520, human squamous cell lung carcinoma; and H1048). Plasma PK were first described by a standard two-compartment model and used as a driver of PD and tumor volume (efficacy). Plasma and tumor PD were modeled using an indirect response model. A hybrid tumor growth coupled with transit compartment mediated tumor killing model was used to fit the tumor volume data. To predict the safety profile of JNJ178, lifespan based indirect response model for erythropoiesis and Friberg myelosuppression model were used to simulate hemoglobin and neutrophil kinetics in human. The PK/PD model described the data well and validated the hypothesis that PD is driven by trough concentration. Based on the exposure-response relationship from the four xenograft models, the trough concentration needed to achieve tumor stasis for mouse was determined. In addition, the level of inhibition in tumor and plasma PD marker that was associated with tumor stasis was identified. Together with human PK parameters scaled using allometry, the dose range needed to achieve target therapeutic exposure for a typical human subject was predicted. Simulation results from erythropoiesis and Friberg myelosuppression models informed the optimal doing schedules for certain dose levels that would allow hematological toxicity to be manageable with 1.0 x 109/L neutrophil counts at all times. Overall, a translational modeling and simulation approach that considers safety and efficacy has been instrumental in the design of the first-in-human clinical development of PRMT5 inhibitor JNJ178 regarding selection of dose and schedule. Citation Format: Yue Guo, Nahor Haddish-Berhane, Hillary J. Millar, Tinne Verhulst, Tony Greway, Junguo Zhou, Loeckie DeZwart, Dana Gaffney, Joseph Portale, Dirk Brehmer, An Boeckx, Erika Van Heerde, Daniele Ouellet. Translational efficacy and safety modeling and simulation to support the clinical development of JNJ-64619178, a PRMT5 inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3905.

PRMT5 is a type II methyltransferase that symmetrically di-methylates arginine residues on proteins involved in signal transduction and cellular transcription. For example, PRMT5 acts as the enzymatic machinery of the methylosome complex, crucial for spliceosome assembly and activity. Although not frequently mutated or amplified in tumors, an elevated PRMT5 protein level that leads to higher methylosome activity and promotes epithelial–mesenchymal transition, has recently been correlated with a poor survival of cancer patients. The PRMT5 inhibitor JNJ-64619178 has been selected as a clinical candidate based on its high selectivity and potency, paired with favorable oral pharmacokinetics and safety properties. JNJ-64619178 binds simultaneously to the SAM- and protein substrate- binding pockets of the PRMT5/MEP50 complex with a pseudo-irreversible mode-of-action. Chemical proteomics, methylomics and RNA-sequencing analyses of PRMT5 inhibitor treated cell line samples support the current biological understanding of PRMT5 as a regulator of alternative splicing events. JNJ-64619178 showed potent and broad inhibition of cellular growth, observed in several cell line panels that represent diverse cancer histologies. Ongoing investigations will explore the potential synthetic lethal correlation between PRMT5 inhibition and cancer driver pathways, including those addicted to altered splicing. Oral administration of JNJ-64619178 resulted in efficient inhibition of di-methylation of SMD1/3 proteins, components of the splicing machinery and direct substrates of the methylosome, in several human NSCLC and SCLC cancer mouse xenograft models. JNJ-64619178 demonstrated dose-dependent tumor growth inhibition and regression in several human NSCLC and SCLC cancer mouse xenograft models with sustained blockage of tumor re-growth after dosing cessation. In summary, JNJ-64619178 has a favorable pre-clinical profile supporting clinical testing in patients with lung cancer and other malignancies. Citation Format: Tongfei Wu, Hillary Millar, Dana Gaffney, Lijs Beke, Geert Mannens, Petra Vinken, Ivan Sommers, Jan-Willem Thuring, Weimei Sun, Christopher Moy, Vineet Pande, Junguo Zhou, Nahor Haddish-Berhane, Mark Salvati, Sylvie Laquerre, Matthew V. Lorenzi, Dirk Brehmer. JNJ-64619178, a selective and pseudo-irreversible PRMT5 inhibitor with potent in vitro and in vivo activity, demonstrated in several lung cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4859.

Introduction: Previously we have shown the utility of Fluorescent Molecular Tomography (FMT) imaging in evaluating bio-distribution of biologics. P-cadherin LP-DART is a bi-specific Dual Affinity Re-Targeting (DART®) molecule targeting CD3 expressed on T-cells and P-cadherin expressed on tumors. In this study we evaluated the bio-distribution and tumor targeting of P-cadherin LP-DART using FMT imaging in a colorectal xenograft model. Methods: NSG or athymic nude mice with subcutaneous HCT-116 xenografts were used. Studies that included engraftment of T-cells received either PBMNCs or T-cells isolated from healthy human volunteers. Bio-distribution studies were initiated when the tumors reached 300-500 mm3. P-cadherin LP-DART or a negative control-DART (non-targeted domain x CD3 binding domain) was conjugated with a near-infrared fluorophore VivoTag680XL (VT680), and the labeling efficiency was determined by spectrophotometer. T-cells used in trafficking studies were labeled with CellVue815. Cell surface P-cadherin expression and P-cadherin LP-DART binding was determined by flow cytometry. T-cell activity was measured with cytotoxic T-lymphocyte (CTL) assays. FMT imaging was performed longitudinally post injection of labeled bi-specifics. Data was analyzed using TrueQuant software. Plasma and tissues were collected for PK analysis by ELISA or histology. Results: VT680 conjugation to P-cadherin LP-DART did not significantly affect the binding to P-cadherin, whereas CD3 binding was decreased. In vivo FMT imaging revealed high levels of P-cadherin LP-DART accumulation in the tumors. The in vivo kinetics revealed that the peak accumulation in tumors was 96hrs post-injection. At 240hrs post-injection, there was still measurable P-cadherin LP-DART detected in tumors. Ex vivo imaging showed 20-25 fold increase in accumulation of P-cadherin LP-DART compared to negative control DART. Comparison of P-cadherin LP-DART accumulation between PBMNC engrafted and non-engrafted model showed no significant difference in quantity or kinetics. There was no significant difference in the kinetics of elimination in the whole-body, heart or liver between P-cadherin LP-DART or negative control. Ex vivo comparison of accumulation in various organs showed no difference between P-cadherin LP-DART or negative control. Cell trafficking studies with CellVue labeled T-cells showed the co-localization of T-cells and P-cadherin LP-DART in tumors. Conclusion: FMT imaging showed that P-cadherin LP-DART specifically targeted HCT-116 tumors. Cell trafficking studies showed that engrafted T-cells accumulated in tumors. This study shows the utility of FMT in bio-distribution studies of biologics and in vivo cell trafficking. Citation Format: Anand Giddabasappa, Vijay Gupta, Timothy S. Fisher, John David, Norberg Rand, Allison Rohner, Justin Cohen, Tracey Clark, Nahor Haddish-Berhane, Adam Root, Chad May. Bio-distribution and tumor targeting of a P-cadherin x CD3 bi-specific redirected T-cell molecule using fluorescence molecular tomography imaging. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5111. doi:10.1158/1538-7445.AM2015-5111

Introduction: Strong evidence exists supporting the important role T-cells play in the immune response against tumors. Still, the ability to initiate tumor specific immune responses remains a challenge. We have developed a Dual-Affinity Re-Targeting (DART®) protein engineered with enhanced pharmacokinetic properties to extend in vivo half-life, and designed to engage and activate endogenous polyclonal T cell populations via the CD3 complex in the presence of P-cadherin expressing tumors. We designate this bispecific redirecting T-cell molecule as P-cadherin LP-DART. P-cadherin up-regulation has been reported in various tumors, including breast, gastric, endometrial, colorectal and pancreatic cancers, and is correlated with poor survival of patients. Methods: The P-cadherin LP-DART was stably expressed by CHO cells and purified to homogeneity via standard antibody-purification methods. Functional in vitro studies were performed with a panel of human cancer cell lines and human T cells isolated from healthy donors. In vivo tumor growth inhibition studies were performed in immunodeficient athymic nude or NOD-scid IL2Rgammanull (NSG) mice bearing human tumor cell line- or patient derived-xenografts and human T-cells, and treated with P-cadherin LP-DART. Results: P-cadherin LP-DART exhibited binding to a broad panel of cancer cell lines expressing various levels of endogenous cell surface P-cadherin, and comparable binding to a number of human donor derived T-cells expressing CD3. In the presence of T-cells, this bispecific molecule elicited P-cadherin expression level dependent cytotoxic T-lymphocyte (CTL) responses against the different tumor cell lines, and induced antigen dependent T-cell activation and cytokine release. P-cadherin LP-DART also demonstrated potent in vivo anti-tumor activity against implanted tumor xenografts. Significant tumor growth inhibition was observed across a range of potential indications that express P-cadherin. Measurement of in vivo pharmacodynamic markers support P-cadherin LP-DART mediated CTL infiltration and killing as the mechanism of tumor inhibition. Conclusions: P-cadherin LP-DART displays potent in vitro and in vivo redirected T-cell activity against a broad panel of cancer cell lines expressing a range of cell surface P-cadherin levels. These data support further investigation of P-cadherin LP-DART as a potential novel therapeutic treatment for cancers expressing P-cadherin. Citation Format: Timothy S. Fisher, Adam Root, Bryan Peano, Allison Rohner, Justin Lucas, Mark Elliott, Konstantinos Tsaparikos, Hui Wang, Jonathan Golas, Maria Gavriil, Susan Benard, Tao He, Tracey Clark, Nahor Haddish-Berhane, Ralph Alderson, Yinhua Yang, Syd Johnson, Paul Moore, Lioudmila Tchistiakova, Hans-Peter Gerber, Chad May. Bispecific redirected T-cell immunotherapy targeting P-cadherin expressing tumors. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2476. doi:10.1158/1538-7445.AM2015-2476

Antibody-drug conjugates (ADCs) represent a promising therapeutic modality for the clinical management of cancer. We sought to develop a novel ADC that targets 5T4 (TPBG), an oncofetal antigen expressed on tumor-initiating cells (TICs), which comprise the most aggressive cell population in the tumor. We optimized an anti-5T4 ADC (A1mcMMAF) by sulfydryl-based conjugation of the humanized A1 antibody to the tubulin inhibitor monomethylauristatin F (MMAF) via a maleimidocaproyl linker. A1mcMMAF exhibited potent in vivo anti-tumor activity in a variety of tumor models and induced long-term regressions for up to 100 days after the last dose. Strikingly, animals showed pathological complete response in each model. In a non-small cell lung cancer patient-derived xenograft in which 5T4 is preferentially expressed on the less differentiated tumor cells, A1mcMMAF treatment resulted in sustained tumor regressions and reduced TIC frequency. These results highlight the potential of ADCs that target the most aggressive cell populations within tumors. An optimized pharmacokinetic/pharmacodynamic (PK/PD) model of tumor growth and drug kill was used to characterize the ADC concentration response relationship in mouse. A holistic secondary parameter, tumor static concentration (TSC), was derived from model parameters to quantify efficacy and support early clinical trial design. Tumor static concentrations [80% confidence] of A1mcMMAF ranged from 1.1[0.9 -1.4] μg/ml to 11.6 [9.6 - 14.1] μg/ml across tumor models. For comparison, in the clinic T-DM1 has an average concentration of 14 μg/ml at an efficacious dose of 3.6 mg/kg Q3wk (HER+ breast cancer) (Krop et al. 2010) and Brentuximab-vedotin has an average concentration of 3.65 μg/ml at an efficacious dose of 1.8 mg/kg Q 3wk (HL/ ALCL) (Younes et al. 2010). Taken together, the preclinical data established a promising therapeutic index that supports clinical testing of A1mcMMAF. Expression analysis profiling using clinical and preclinical data indicated that lung and breast tumors demonstrated differentially high expression of 5T4 in comparison to normal tissues. An IHC assay developed in house confirmed the hypothesis that a broad range of 5T4 expression was measurable in NSCLC patient tumor samples. Additionally, we developed an assay that measures 5T4 expression on circulating tumor cells (CTCs) and used this assay to measure and characterize a broad range of 5T4 expression in CTCs obtained from the blood of NSCLC patients. We intend to deploy these co-developed immunoassays to guide A1mcMMAF clinical development. Citation Format: Puja Sapra, Marc Damelin, Kimberly Marquette, Kenneth G. Geles, Jonathon Golas, Maureen Dougher, Bitha Narayanan, Andreas Giannakou, Kiran Khandke, Russell Dushin, Elana Ernstoff, Judy Lucas, Mauricio Leal, George Hu, Alison Betts, Nahor Haddish-Berhane, Eric Powell, Steven Pirie-Shepherd, Christopher O'Donnell, Lioudmila Tchistiakova, Hans-Peter Gerber, Dena Marrinucci, Eric Tucker. Preclinical development and translational research on a novel antibody-drug conjugate that targets 5T4, an oncofetal antigen expressed on tumor-initiating cells. [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 4752. doi:10.1158/1538-7445.AM2013-4752