JNJ-39758979

Phase 2a, randomized, double-blind, placebo-controlled, multicentre, parallel-group study of an H4 R-antagonist (JNJ-39758979) in adults with uncontrolled asthma

Background: The effects of H4 R antagonists in preclinical asthma models support the study of antagonists of the H4 R in the treatment of asthma in humans. JNJ-39758979 is a potent and highly selective oral H4 R antagonist. Objective: We sought to evaluate the safety and efficacy of the H4 R-antagonist JNJ-39758979 in adult patients with uncontrolled asthma. Methods: One hundred and fifteen eligible patients were randomly assigned to JNJ-39758979 300 mg or placebo once daily for 12 weeks in this phase 2a, double-blind, multicenter, placebo-controlled study. Primary efficacy was assessed via week-12 change from baseline in pre-bronchodilator forced expiratory volume in 1 second (FEV1 ). Secondary efficacy assessments included patient-reported outcome (PRO) asthma assessments (Asthma Daily Diary data [AM and PM peak expiratory flow rate, number of puffs of albuterol/salbutamol, the presence of nocturnal awakenings and asthma symptom score]). Results: The study did not meet the primary end-point. However, nominally significant improvements in pre-bronchodilator FEV1 were observed with JNJ-39758979 versus placebo at week 12 in pre-specified subgroups with elevated exhaled nitric oxide, sputum eosinophils or blood eosinophils at baseline. Nominally significant improvements across PRO assessments were consistently observed in the overall population, as well as in eosinophilic subgroups. Safety, such as adverse event rates, was comparable between JNJ-39758979 and placebo. No serious adverse events were reported. No clinically relevant changes in laboratory values were observed. Conclusions and clinical relevance: The findings suggest potential benefit of H4 R antagonists on lung function and asthma control in eosinophilic asthma patients and warrant further evaluation of this mechanism in asthma with eosinophilic inflammation. NCT00946569.

The histamine H? receptor antagonist, JNJ 39758979, is effective in reducing histamine-induced pruritus in a randomized clinical study in healthy subjects

The histamine H4 receptor (H4R) is a promising target for the treatment of pruritus. A clinical study was conducted to evaluate the safety and efficacy of the H4R antagonist, JNJ 39758979 [(R)-4-(3-amino-pyrrolidin-1-yl)-6-isopropyl-pyrimidin-2-ylamine], on histamine-induced pruritus in healthy subjects. A single oral dose of 600 mg JNJ 39758979, 10 mg cetirizine, or placebo was administered in a randomized, three-period, double-blind, crossover study. Treatment periods were separated by 22-day washout periods. A histamine challenge was administered on day -1 and at 2 and 6 hours postdose on day 1 of each treatment period. The primary efficacy endpoint was the area under the curve (AUC) of pruritus score 0-10 minutes after the histamine challenge. Secondary efficacy endpoints included wheal and flare areas assessed 10 minutes after the histamine challenge. Safety was assessed for all subjects. Of the 24 enrolled subjects, 23 individuals completed the study. One subject withdrew after completing two treatment periods. Due to a carryover effect of JNJ 39758979, only treatment period 1 was used for pruritus-related evaluations. Compared with placebo, the reduction of the AUC of pruritus score was significant for JNJ 39758979 at 2 hours (P = 0.0248) and 6 hours (P = 0.0060), and for cetirizine at 6 hours (P = 0.0417). In all treatment periods, JNJ 39758979 did not demonstrate a significant decrease in wheal or flare at either time point, although a significant reduction was achieved with cetirizine at 2 and 6 hours (P < 0.0001). Adverse eventss reported in >1 patient with JNJ 39758979 were headache (9%) and nausea (13%). In conclusion, JNJ 39758979 was effective in inhibiting histamine-induced pruritus in healthy subjects.

Clinical and preclinical characterization of the histamine H(4) receptor antagonist JNJ-39758979

The histamine H4 receptor (H(4)R) has been shown to have preclinical involvement in both inflammatory and pruritic responses. JNJ-39758979 [(R)-4-(3-amino-pyrrolidin-1-yl)-6-isopropyl-pyrimidin-2-ylamine] is a potent and selective H(4)R antagonist with a Ki at the human receptor of 12.5 ± 2.6 nM and greater than 80-fold selectivity over other histamine receptors. The compound also exhibited excellent selectivity versus other targets. JNJ-39758979 showed dose-dependent activity in models of asthma and dermatitis consistent with other H(4)R antagonists. Preclinical toxicity studies of up to 6 months in rats and 9 months in monkeys indicated an excellent safety profile, supporting the clinical testing of the compound. An oral formulation of JNJ-39758979 was studied in a phase 1 human volunteer study to assess safety, pharmacokinetics, and pharmacodynamics. The compound was well tolerated, with the exception of dose-dependent nausea, and no safety issues were noted in the phase 1 study. JNJ-39758979 exhibited good pharmacokinetics upon oral dosing with a plasma half-life of 124-157 hours after a single oral dose. In addition, dose-dependent inhibition of histamine-induced eosinophil shape change was detected, suggesting that the H4R was inhibited in vivo. In conclusion, JNJ-39758979 is a potent and selective H(4)R antagonist that exhibited good preclinical and phase 1 safety in healthy volunteers with evidence of a pharmacodynamics effect in humans.

Phase 2a, randomized, double-blind, placebo-controlled, multicenter, parallel-group study of a H4 R-antagonist (JNJ-39758979) in Japanese adults with moderate atopic dermatitis

This trial was conducted to evaluate the safety and efficacy of the H4 R-antagonist JNJ-39758979 in adult Japanese patients with moderate atopic dermatitis (AD). Eligible patients were randomly assigned to JNJ-39758979 300 mg, 100 mg or placebo once daily for 6 weeks in this phase 2a, double-blind, multicenter, placebo-controlled study. Primary efficacy was assessed via week-6 Eczema Area and Severity Index (EASI) scores. Secondary efficacy assessments included Investigator's Global Assessment (IGA) and patient-reported outcome (PRO) pruritus assessments (Pruritus Categorical Response Scale [PCRS], Pruritus Numeric Rating Scales [PNRS], Pruritus Interference Numeric Rating Scale [PINRS] and Subject's Global Impressions of Change in Pruritus [SGICP]). Eighty-eight of 105 planned patients were randomized before the study was stopped and unblinded for safety reasons. The study did not meet the primary end-point. However, numerical improvements (i.e. decreases) in median EASI were observed with JNJ-39758979 100 mg (-3.7) and 300 mg (-3.0) versus placebo (-1.3) at week 6. Nominally significant improvements across PRO PCRS, PNRS and SGICP assessments were consistently observed, particularly with JNJ-39758979 300 mg. Safety, including adverse events (AE), was comparable between JNJ-39758979 and placebo with the exception of two patients (both receiving JNJ-39758979 300 mg) with serious AE of neutropenia, leading to premature study discontinuation. No deaths were reported. Except for neutropenia, no clinically relevant changes in laboratory values were observed. Although not conclusive, findings suggest H4 R-antagonism may be beneficial for AD, particularly in controlling pruritus. JNJ-39758979 appears to be associated with drug-induced agranulocytosis, likely an off-target effect.

Clinical Development of Histamine H4 Receptor Antagonists

The discovery of the histamine H₄ receptor (H₄R) provided a new avenue for the exploration of the physiological role of histamine, as well as providing a new drug target for the development of novel antihistamines. The first step in this process was the identification of selective antagonists to help unravel the pharmacology of the H₄R relative to other histamine receptors. The discovery of the selective H₄R antagonist JNJ 7777120 was vital for showing a role for the H₄R in inflammation and pruritus. While this compound has been very successful as a tool for understanding the function of the receptor, it has drawbacks, including a short in vivo half-life and hypoadrenocorticism toxicity in rats and dogs, that prevented advancing it into clinical studies. Further research let to the discovery of JNJ 39758979, which, similar to JNJ 7777120, was a potent and selective H₄R antagonist and showed anti-inflammatory and anti-pruritic activity preclinically. JNJ 39758979 advanced into human clinical studies and showed efficacy in reducing experimental pruritus and in patients with atopic dermatitis. However, development of this compound was terminated due to the occurrence of drug-induced agranulocytosis. This was overcome by developing another H₄R antagonist with a different chemical structure, toreforant, that does not appear to have this side effect. Toreforant has been tested in clinical studies in patients with rheumatoid arthritis, asthma, or psoriasis. In conclusions there have been many H₄R antagonists reported in the literature, but only a few have been studied in humans underscoring the difficulty in finding ligands with all of the properties necessary for testing in the clinic. Nevertheless, the clinical data to date suggests that H₄R antagonists can be beneficial in treating atopic dermatitis and pruritus.