Genome-wide association study identifies multiple HLA loci for sarcoidosis susceptibility.

Sarcoidosis is a complex systemic disease. Our study aimed to (1) identify novel alleles associated with sarcoidosis susceptibility; (2) provide an in-depth evaluation of HLA alleles and sarcoidosis susceptibility and (3) integrate genetic and transcription data to identify risk loci that may more directly impact disease pathogenesis. We report a genome-wide association study of 1335 sarcoidosis cases and 1264 controls of European descent (EA) and investigate associated alleles in a study of African Americans (AA: 1487 cases and 1504 controls). The EA and AA cohort was recruited from multiple United States sites. HLA alleles were imputed and tested for association with sarcoidosis susceptibility. Expression quantitative locus and colocalization analysis were performed using a subset of subjects with transcriptome data. Forty-nine SNPs in the HLA region in HLA-DRA, -DRB9, -DRB5, -DQA1 and BRD2 genes were significantly associated with sarcoidosis susceptibility in EA, rs3129888 was also a risk variant for sarcoidosis in AA. Classical HLA alleles DRB1*0101, DQA1*0101 and DQB1*0501, which are highly correlated, were also associated with sarcoidosis. rs3135287 near HLA-DRA was associated with HLA-DRA expression in peripheral blood mononuclear cells and bronchoalveolar lavage from subjects and lung tissue and whole blood from GTEx. We identified six novel SNPs (out of the seven SNPs representing the 49 significant SNPs) and nine HLA alleles associated with sarcoidosis susceptibility in the largest EA population. We also replicated our findings in an AA population. Our study reiterates the potential role of antigen recognition and/or presentation HLA class II genes in sarcoidosis pathogenesis.

The efficacy and tolerability of MK-0633, a 5-lipoxygenase inhibitor, in chronic asthma.

Leukotriene B4 (LTB(4)) is a potent inflammatory mediator in asthma, and is increased in more severe asthma. Targeting LTB(4), in addition to cysteinyl leukotrienes, could be beneficial in asthma. This was a randomized, double-blind trial of once-daily MK-0633, a potent 5-lypoxygenase inhibitor, 10 mg, 50 mg, and 100 mg, and placebo in patients 18-70 years with a history of chronic asthma, and FEV(1) ≥45 and ≤85% predicted. There was a 6-week main period and optional 18-week and 34-week periods (52 weeks total), the latter two comparing only MK-0633 100 mg and placebo. The primary endpoint was the change from baseline in FEV(1) over the last 4 weeks of the 6-week primary treatment period. Secondary endpoints included symptom scores, ß-agonist use, peak expiratory flow (PEF), asthma quality of life questionnaire (AQLQ), asthma control questionnaire (ACQ), asthma attacks, exacerbations, days with asthma control, post-ß-agonist FEV(1), and blood eosinophils. MK-0633 100 mg was significantly more effective than placebo for the change from baseline in FEV(1) (0.20 L vs. 0.13 L; p = 0.004). The other MK-0633 doses were not significantly more effective than placebo. MK-0633 (at various doses) was also more effective than placebo for ß-agonist use, AQLQ, AM and PM PEFR, ACQ, and post-ß-agonist FEV(1) (p < 0.05 for all). MK-0633 was associated with a dose-dependent increase in elevated aspartate aminotransferase and alanine aminotransferase. Because of the relative benefit-risk ratio, the optional study periods were terminated after unblinding for the main study period. Overall, the benefit-risk ratio did not support the clinical utility of MK-0633 in asthma.

Onset and duration of attenuation of exercise-induced bronchoconstriction in children by single-dose of montelukast.

Single-dose montelukast attenuates exercise-induced bronchoconstriction (EIB) in adults within 2 hours postdose and lasting through 24 hours. This study evaluated the onset and duration of EIB attenuation in children after a single dose of montelukast. A randomized, double-blind, placebo-controlled, two-period crossover study was performed. Patients (n = 66) aged 4-14 years, with preexercise forced expiratory volume in 1 second of (FEV(1)) ≥70% predicted and maximum percentage fall in FEV(1) of ≥20% at two screening exercise challenges were eligible. Patients were to receive single-dose montelukast (4 or 5 mg) or placebo before performing standardized exercise challenges at 2 and 24 hours postdose. A 3- to-7-day washout separated the two crossover periods. The primary end point was maximum percentage fall in FEV(1) after exercise challenge 2 hours postdose. Secondary end points included maximum percentage fall in FEV(1) after the 24-hour postdose challenge; each of the following at 2 and 24 hours postdose-maximum percentage fall in FEV(1) categorized as <10%, 10-20%, or >20%; area under the curve (AUC) during 60 minutes postchallenge; time to recovery of FEV(1) to within 5% of preexercise baseline; and need for rescue medication. The mean maximum percentage fall in FEV(1) after the 2-hour postdose exercise challenge was significantly attenuated after single-dose montelukast compared with placebo (15.35% versus 20.00%; p = 0.020). Montelukast was also significantly more effective than placebo for maximum percentage fall after the 24-hour challenge (12.92% versus 17.25%; p = 0.005), the categorized maximum percent fall in FEV(1) at 2 hours (p = 0.034), and AUC at 2 hours (p = 0.022) and 24 hours (p = 0.013). Single-dose montelukast provided rapid and sustained EIB attenuation in children. Clinicaltrials.gov identifier: NCT00534976.

A new tool to assess sarcoidosis severity.

STUDY OBJECTIVES: Sarcoidosis is a granulomatous disorder primarily affecting the lung, but with frequent extrapulmonary organ involvement. There are no comprehensive scoring systems for sarcoidosis disease severity. Our goal was to develop and validate an objective and comprehensive sarcoidosis disease severity scoring system. DESIGN: Three sarcoidosis experts reviewed clinical data on 104 patients with biopsy-confirmed sarcoidosis. Each expert independently scored disease severity using a visual analog scale. Interrater agreement was assessed. Univariate analysis was performed, and those variables with p values < or = 0.25 were used in backward regression multivariable analysis. A model was obtained including variables with a p value of < or = 0.15 to predict severity scores. This model was subsequently validated using an independent panel of three additional international experts. SETTING: Granuloma clinic at National Jewish Medical and Research Center. PATIENTS: A total of 104 patients with biopsy-confirmed sarcoidosis. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Pairwise assessment of interrater agreement yielded high degrees of correlation with Spearman correlation coefficients of 0.86 to 0.89 and an intraclass correlation coefficient of 0.87. Univariate analysis showed that smoking status, immunosuppressive therapy, percent predicted for diffusing capacity of the lung for carbon monoxide (Dlco), FEV1, FVC, and total lung capacity, FEV1/FVC ratio, disease duration, sites of organ involvement, and African-American race were associated with mean severity score. The multivariable model included cardiac and neurologic involvement, current therapy with noncorticosteroid immunosuppressive agents, Dlco percent predicted, FEV1/FVC ratio, African-American race, FVC percent predicted, and skin involvement. This model was validated using additional reviewer scores yielding Spearman correlation coefficients of 0.66 to 0.76 and an intraclass correlation coefficient of 0.74. CONCLUSIONS: We derived an objective disease severity scoring system that incorporates data on demographics, pulmonary function, and organ involvement to produce a whole-body sarcoidosis assessment. This preliminary tool has potential applicability in the assessment of disease severity in sarcoidosis research.