Inhibition by auranofin of pharmacologic and antigen-induced contractions of the isolated guinea pig trachea

A placebo-controlled multicenter study of auranofin in the treatment of patients with corticosteroid-dependent asthma. Auranofin Multicenter Drug Trial

BACKGROUND

Previous clinical studies have demonstrated that injectable gold salts and the oral gold compound, auranofin, possess significant steroid-sparing effects in the treatment of asthma.

OBJECTIVES

The objectives of this investigation were to determine whether auranofin could reduce oral corticosteroid requirements and to evaluate the safety of auranofin in the treatment of chronic corticosteroid-dependent asthma.

METHODS

Patients with asthma were eligible if they required at least 10 mg of prednisone per day for control and prevention of asthma exacerbations. Two hundred seventy-nine patients with chronic corticosteroid-dependent asthma (requiring > or = 10 mg/day) were randomized to receive auranofin, 3 mg twice daily, or placebo during an 8-month clinical trial, which was divided into three phases including: a 4-week baseline period (phase I), a 6-month double-blind treatment and steroid reduction period (phase II), and a 4-week posttreatment observation period during which steroid and auranofin doses or placebo doses were maintained at levels achieved by the end of phase II (phase III). The primary efficacy variable was "therapeutic success" or reduction of daily corticosteroid use by 50% or more.

RESULTS

The proportion of patients in the auranofin group achieving therapeutic success (41%) was significantly higher than that in the placebo group (27%) (p = 0.01). This effect was greatest in patients requiring 10 to 19 mg of oral prednisone per day at baseline (p < 0.001). In all treated patients, including those who did and did not complete the trial, significant reduction (> or = 50% of baseline) in oral corticosteroid dosage was achieved in the auranofin group (60%) compared with the placebo group (32%) (p < 0.001). There were no significant differences between treatment groups in symptoms, concomitant medication use, or lung function. Mean serum total IgE levels decreased significantly from baseline in the auranofin group (-44.63 IU/ml) compared with the placebo group (p = 0.001). Gastrointestinal and cutaneous adverse events were greater in the auranofin group.

CONCLUSIONS

Auranofin demonstrated a steroid-sparing effect without concomitant worsening of symptoms or lung function and appeared to be more effective in patients dependent on 10 to 19 mg of prednisone per day. Therefore this study has demonstrated that auranofin is useful as a steroid-sparing agent in the treatment of chronic corticosteroid-dependent asthma.

Modulation of mediator release from human basophils and pulmonary mast cells and macrophages by auranofin

Auranofin, a new orally absorbable gold compound, inhibits IgE-(anti-IgE) and non-IgE-mediated (f-met-peptide and the Ca2+ ionophore A23187) histamine release from human basophils. Auranofin inhibits the release of histamine induced by phorbol myristate (TPA) and bryostatin 1 both in the presence and absence of extracellular Ca2+. Increasing the Ca2+ concentrations in the extracellular medium does not reduce the inhibitory effect of auranofin on anti-IgE- or A23187-induced secretion. Auranofin inhibits the de novo synthesis of sulfidopeptide leukotriene C4 (LTC4) induced by anti-IgE from basophils and mast cells purified from human lung. However, in both systems auranofin has a significantly greater inhibitory effect on LTC4 release than on histamine secretion. Finally, auranofin induces a concentration-dependent inhibition of A23187-induced leukotrine B4 (LTB4) release from purified human lung macrophages. These data suggest that auranofin modulates the release of preformed (histamine) and de novo synthesized (LTC4 and LTB4) chemical mediators from human inflammatory cells isolated from peripheral blood and human lung tissues.

An open study of auranofin in the treatment of steroid-dependent asthma

To determine the efficacy of oral gold in asthma, 20 patients with steroid-dependent asthma received auranofin at a dose of 3 mg by mouth, twice daily, in a 24-week open clinical trial. Prospective evaluation of bronchial responsiveness to methacholine was determined before and 8 and 16 weeks after initiation of auranofin therapy. Serial spirometry (FEV1 and FVC), lung volumes, and diffusing capacities (single breath carbon monoxide diffusing capacity of the lungs) were measured before and at 10 and 20 weeks after treatment. All subjects were required to record concomitant medications, symptom scores, and morning and evening peak expiratory flow rates. In vitro immunologic studies performed before and after 8 and 20 weeks of auranofin therapy included leukocyte histamine release in response to antihuman IgE, lymphocyte blast transformation in response to concanavalin A and phytohemagglutinin, and leukocyte inhibitory factor activity in response to Candida albicans and tetanus toxoid antigens. In 18 patients evaluated, there were no significant differences between baseline and posttreatment spirometry, single breath carbon monoxide diffusing capacity of the lungs, and lung volumes. At week 16 of treatment, the steroid cumulative dose or the total prednisone dose administered from 7 days before through 10 days after each methacholine test day decreased from a mean of 293 +/- 125 mg at baseline to 192 +/- 115 mg. At week 16, nine of 18 patients (50%) exhibited decreased methacholine responsiveness as defined by a more than one-half log10 increase in the concentration of methacholine causing a 20% decrease in FEV1. A significant correlation (r = 0.60) was observed between the increase in the concentration of methacholine causing a 20% decrease in FEV1 and the decrease in steroid cumulative dose after 16 weeks of treatment. Leukocyte histamine release to anti-IgE exhibited significant reductions from baseline at week 20 to 10(-2) (p less than 0.002) and at 10(-3) (p less than 0.005) dilutions. At week 20, leukocyte inhibitory factor activity in response to Candida increased from baseline at the 0.1 mg per well (p = 0.025) and 1 mg per well (p = 0.05) concentrations; similarly, the responses to tetanus toxoid increased at the 1 mg per well (p less than 0.05) and 0.1 mg per well (p less than 0.01) concentrations.(ABSTRACT TRUNCATED AT 400 WORDS)