Preclinical and clinical characterization of the RORγt inhibitor JNJ-61803534

Abstract

The nuclear receptor retinoid-related orphan receptor gamma t (RORγt) plays a critical role in driving Th17 cell differentiation and expansion, as well as IL-17 production in innate and adaptive immune cells. The IL-23/IL-17 axis is implicated in several autoimmune and inflammatory diseases, and biologics targeting IL-23 and IL-17 have shown significant clinical efficacy in treating psoriasis and psoriatic arthritis. JNJ-61803534 is a potent RORγt inverse agonist, selectively inhibiting RORγt-driven transcription versus closely-related family members, RORα and RORβ. JNJ-61803534 inhibited IL-17A production in human CD4⁺ T cells under Th17 differentiation conditions, but did not inhibit IFNγ production under Th1 differentiation conditions, and had no impact on in vitro differentiation of regulatory T cells (Treg), nor on the suppressive activity of natural Tregs. In the mouse collagen-induced arthritis model, JNJ-61803534 dose-dependently attenuated inflammation, achieving ~ 90% maximum inhibition of clinical score. JNJ-61803534 significantly inhibited disease score in the imiquimod-induced mouse skin inflammation model, and dose-dependently inhibited the expression of RORγt-regulated genes, including IL-17A, IL-17F, IL-22 and IL-23R. Preclinical 1-month toxicity studies in rats and dogs identified doses that were well tolerated supporting progression into first-in-human studies. An oral formulation of JNJ-61803534 was studied in a phase 1 randomized double-blind study in healthy human volunteers to assess safety, pharmacokinetics, and pharmacodynamics. The compound was well tolerated in single ascending doses (SAD) up to 200 mg, and exhibited dose-dependent increases in exposure upon oral dosing, with a plasma half-life of 164 to 170 h. In addition, dose-dependent inhibition of ex vivo stimulated IL-17A production in whole blood was observed, demonstrating in vivo target engagement. In conclusion, JNJ-61803534 is a potent and selective RORγt inhibitor that exhibited acceptable preclinical safety and efficacy, as well as an acceptable safety profile in a healthy volunteer SAD study, with clear evidence of a pharmacodynamic effect in humans.

Figure 1

Structure and selectivity of JNJ-61803534 for inhibition of RORγt-driven transcription. (a) Structure of JNJ-61803534. (b) Activity of JNJ-61803534 in 1-hybrid reporter assays. HEK-293 T cells were transfected with vectors encoding RORγt, RORα or RORβ, respectively, fused with the GAL4 DNA binding domain. After incubation with compound overnight, luciferase signals were measured. JNJ-61803534 was tested at a starting concentration of 2 μM in three-fold serial dilutions in duplicate.

Figure 2

Effects of JNJ-61803534 on human immune cells. (a) Effect of JNJ-61803534 on IL-17A, IL-17F and IL-22 production in human CD4⁺ T cells under Th17 differentiation, and on IFNγ production in human CD4⁺ T cells under Th1 conditions, respectively. Data are averages of duplicates and presented as the percentage of vehicle control group. (b) Effect of JNJ-61803534 on FOXP3 gene expression after 6 days under Treg differentiation conditions. Data are presented as fold change in gene expression over vehicle control group (mean ± SD, n = 3). (c) Effect of JNJ-61803534 on Treg suppression of IFNγ production from effector T cells. Data are presented as mean ± SD, n = 3. (d) Dose-dependent inhibition of IL-17A production in 1:1 diluted human whole blood by JNJ-61803534. Data are average of duplicates.

Figure 3

Effect of JNJ-61803534 in a mouse pharmacokinetics (PK)/pharmacodynamic (PD) model. (a) Time course of JNJ-61803534 concentration in plasma, and (b) Time course of inhibition of ex vivo stimulated IL-17A production by JNJ-61803534, at 100 mg/kg dosed orally. IL-17A values are presented as mean ± SEM of each time point of vehicle and treated group (n = 10). Unpaired t-test: *p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001.

Figure 4

Effect of JNJ-61803534 in a mouse CIA model. (a) Time course of clinical arthritic score. (b) Histopathology score of the paws at the end of study. JNJ-61803534 was dosed orally at 3, 10, 30, 100 mg/kg/day, BID, or 60 mg/kg QD from day 21–35. Data represent mean ± SEM (n = 9–12 per group except naïve group n = 4, and Dex group = 6). *p < 0.05, ****p < 0.0001 vs Vehicle (Kruskal–Wallis, Dunn’s Multiple Comparison post-test).

Figure 5

Effect of JNJ-61803534 in IMQ-induced skin inflammation in mice. (a) Cumulative skin scores on day 7 of the mouse IMQ model. Disease scores (thickness, redness, scaling) of back skin were measured prior to each morning dose and presented as mean ± SEM of 5 individual animal. (b) Gene expression (IL-17A, IL-17F and IL-22) in the ears of the mice. Data are presented as mean ± SEM of fold change over control cream group for each individual animal (n = 5). The relative expression level was calculated based on the formula: 2^ (β2M CT-Target Gene CT) * 10,000. (c) Number of IL-17A⁺ and IL-17A⁺/IL-22⁺ γδ T cells in the ears. Statistical analyses were performed with one-way ANOVA, *p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001.

Figure 6

Pharmacokinetics and pharmacodynamics of JNJ-61803534 in healthy subject SAD phase I study. (a) Plasma concentrations of compound versus time. Data presented as mean ± SD. (b) Percentage of ex vivo IL-17A inhibition versus time, after single dose administration or placebo under fasted or fed conditions. Data are presented as median ± maximum/minimum. For both analyses, n = 6 for 10, 30 and 200 mg groups, n = 9 for 100 mg fed and fasted groups, n = 9 for placebo fasted group, and n = 3 for placebo fed groups.