Association of the TNF-α G-308A polymorphism with TNF-inhibitor response in sarcoidosis

PA Wijnen, JP Cremers, PJ Nelemans… - European …, 2014 - Eur Respiratory Soc
PA Wijnen, JP Cremers, PJ Nelemans, RJ Erckens, E Hoitsma, TL Jansen, O Bekers
European Respiratory Journal, 2014Eur Respiratory Soc
Responsiveness to tumour necrosis factor (TNF) inhibitors has been associated with the
TNF-α G-308A polymorphism in rheumatoid arthritis. The aim of this study was to examine
the association between the presence of this polymorphism and the response to TNF
inhibitors in patients with refractory sarcoidosis. Patients (n= 111) who started TNF-inhibitor
treatment (76 infliximab, 35 adalimumab) were followed for at least 1 year. The main
symptoms in these patients were fatigue (n= 100, 90.1%), small fibre neuropathy (n= 91 …
Responsiveness to tumour necrosis factor (TNF) inhibitors has been associated with the TNF-α G-308A polymorphism in rheumatoid arthritis. The aim of this study was to examine the association between the presence of this polymorphism and the response to TNF inhibitors in patients with refractory sarcoidosis.
Patients (n=111) who started TNF-inhibitor treatment (76 infliximab, 35 adalimumab) were followed for at least 1 year. The main symptoms in these patients were fatigue (n=100, 90.1%), small fibre neuropathy (n=91, 82.0%), pulmonary involvement (n=69, 62.2%), and/or uveitis (n=31, 27.9%). Patients were additionally genotyped for the presence of the TNF-α G-308A polymorphism. Treatment response was assessed using clinical outcome measures and questionnaires.
Three-quarters (n=83, 74.8%) of the patients responded well. Of the patients without the variant A-allele 93.6% (73 out of 78, p<0.001) improved, while 30.3% (10 out of 33) of variant A-allele carriers responded favourably to TNF inhibitors. For patients with the GG-genotype, the probability of improving compared with remaining stable or deteriorating was three times higher (risk ratio 3.09, 95% CI 1.84–5.20).
Sarcoidosis patients without the TNF-α -308A variant allele (GG-genotype) had a three-fold higher response to TNF inhibitors (adalimumab or infliximab). Further research is needed to evaluate the value of genotyping for the TNF-α G-308A polymorphism in order to tailor TNF-inhibitor treatment.
European Respiratory Society