Abatacept in interstitial lung disease associated with rheumatoid arthritis: national multicenter study of 263 patients

Objective

To assess the efficacy of abatacept (ABA) in RA patients with interstitial lung disease (ILD) (RA-ILD).

Methods

This was an observational, multicentre study of RA-ILD patients treated with at least one dose of ABA. ILD was diagnosed by high-resolution CT (HRCT). We analysed the following variables at baseline (ABA initiation), 12 months and at the end of the follow-up: Modified Medical Research Council (MMRC) scale (1-point change), forced vital capacity (FVC) or diffusion lung capacity for carbon monoxide (DLCO) (improvement or worsening ≥10%), HRCT, DAS on 28 joints evaluated using the ESR (DAS28ESR) and CS-sparing effect.

Results

We studied 263 RA-ILD patients [150 women/113 men; mean (s.d.) age 64.6 (10) years]. At baseline, they had a median duration of ILD of 1 (interquartile range 0.25–3.44) years, moderate or severe degree of dyspnoea (MMRC grade 2, 3 or 4) (40.3%), FVC (% of the predicted) mean (s.d.) 85.9 (21.8)%, DLCO (% of the predicted) 65.7 (18.3) and DAS28ESR 4.5 (1.5). The ILD patterns were: usual interstitial pneumonia (UIP) (40.3%), non-specific interstitial pneumonia (NSIP) (31.9%) and others (27.8%). ABA was prescribed at standard dose, i.v. (25.5%) or s.c. (74.5%). After a median follow-up of 12 (6–36) months the following variables did not show worsening: dyspnoea (MMRC) (91.9%); FVC (87.7%); DLCO (90.6%); and chest HRCT (76.6%). A significant improvement of DAS28ESR from 4.5 (1.5) to 3.1 (1.3) at the end of follow-up (P < 0.001) and a CS-sparing effect from a median 7.5 (5–10) to 5 (2.5–7.5) mg/day at the end of follow-up (P < 0.001) was also observed. ABA was withdrawn in 62 (23.6%) patients due to adverse events (n = 30), articular inefficacy (n = 27), ILD worsening (n = 3) and other causes (n = 2).

Conclusion

ABA may be an effective and safe treatment for patients with RA-ILD.

Validation study of genetic biomarkers of response to TNF inhibitors in rheumatoid arthritis

Genetic biomarkers are sought to personalize treatment of patients with rheumatoid arthritis (RA), given their variable response to TNF inhibitors (TNFi). However, no genetic biomaker is yet sufficiently validated. Here, we report a validation study of 18 previously reported genetic biomarkers, including 11 from GWAS of response to TNFi. The validation was attempted in 581 patients with RA that had not been treated with biologic antirheumatic drugs previously. Their response to TNFi was evaluated at 3, 6 and 12 months in two ways: change in the DAS28 measure of disease activity, and according to the EULAR criteria for response to antirheumatic drugs. Association of these parameters with the genotypes, obtained by PCR amplification followed by single-base extension, was tested with regression analysis. These analyses were adjusted for baseline DAS28, sex, and the specific TNFi. However, none of the proposed biomarkers was validated, as none showed association with response to TNFi in our study, even at the time of assessment and with the outcome that showed the most significant result in previous studies. These negative results are notable because this was the first independent validation study for 12 of the biomarkers, and because they indicate that prudence is needed in the interpretation of the proposed biomarkers of response to TNFi even when they are supported by very low p values. The results also emphasize the requirement of independent replication for validation, and the need to search protocols that could increase reproducibility of the biomarkers of response to TNFi.

Replication of PTPRC as genetic biomarker of response to TNF inhibitors in patients with rheumatoid arthritis

Genetic biomarkers could be useful for orienting treatment of patients with rheumatoid arthritis (RA), but none has been convincingly validated yet. Putative biomarkers include 14 single nucleotide polymorphisms that have shown association with response to TNF inhibitors (TNFi) in candidate gene studies and that we assayed here in 755 RA patients. Three of them, in the PTPRC, IL10 and CHUK genes, were significantly associated with response to TNFi. The most significant result was obtained with rs10919563 in PTPRC, which is a confirmed RA susceptibility locus. Its RA risk allele was associated with improved response (B=0.33, P=0.006). This is the second independent replication of this biomarker (P=9.08 × 10(-8) in the combined 3003 RA patients). In this way, PTPRC has become the most replicated genetic biomarker of response to TNFi. In addition, the positive but weaker replication of IL10 and CHUK should stimulate further validation studies.

Rheumatoid arthritis response to treatment across IgG1 allotype - anti-TNF incompatibility: a case-only study

Introduction

We have hypothesized that incompatibility between the G1m genotype of the patient and the G1m1 and G1m17 allotypes carried by infliximab (INX) and adalimumab (ADM) could decrease the efficacy of these anti-tumor necrosis factor (anti-TNF) antibodies in the treatment of rheumatoid arthritis (RA).

Methods

The G1m genotypes were analyzed in three collections of patients with RA totaling 1037 subjects. The first, used for discovery, comprised 215 Spanish patients. The second and third were successively used for replication. They included 429 British and Greek patients and 393 Spanish and British patients, respectively. Two outcomes were considered: change in the Disease Activity Score in 28 joint (ΔDAS28) and the European League Against Rheumatism (EULAR) response criteria.

Results

An association between less response to INX and incompatibility of the G1m1,17 allotype was found in the discovery collection at 6 months of treatment (P = 0.03). This association was confirmed in the replications (P = 0.02 and 0.08, respectively) leading to a global association (P = 0.001) that involved a mean difference in ΔDAS28 of 0.4 units between compatible and incompatible patients (2.3 ± 1.5 in compatible patients vs. 1.9 ± 1.5 in incompatible patients) and an increase in responders and decrease in non-responders according to the EULAR criteria (P = 0.03). A similar association was suggested for patients treated with ADM in the discovery collection, but it was not supported by replication.

Conclusions

Our results suggest that G1m1,17 allotypes are associated with response to INX and could aid improved therapeutic targeting in RA.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0571-z) contains supplementary material, which is available to authorized users.

Lack of validation of genetic variants associated with anti-tumor necrosis factor therapy response in rheumatoid arthritis: a genome-wide association study replication and meta-analysis

INTRODUCTION

In this study, our aim was to elucidate the role of four polymorphisms identified in a prior large genome-wide association study (GWAS) in which the investigators analyzed the responses of patients with rheumatoid arthritis (RA) to treatment with tumor necrosis factor inhibitors (TNFi). The authors of that study reported that the four genetic variants were significantly associated. However, none of the associations reached GWAS significance, and two subsequent studies failed to replicate these associations.

METHODS

The four polymorphisms (rs12081765, rs1532269, rs17301249 and rs7305646) were genotyped in a total of 634 TNFi-treated RA patients of Spanish Caucasian origin. Four outcomes were evaluated: changes in the Disease Activity Score in 28 joints (DAS28) after 6 and 12 months of treatment and classification according to the European League Against Rheumatism (EULAR) response criteria at the same time points. Association with DAS28 changes was assessed by linear regression using an additive genetic model. Contingency tables of genotype and allele frequencies between EULAR responder and nonresponder patients were compared. In addition, we combined our data with those of previously reported studies in a meta-analysis including 2,998 RA patients.

RESULTS

None of the four genetic variants showed an association with response to TNFi in any of the four outcomes analyzed in our Spanish patients. In addition, only rs1532269 yielded a suggestive association (P = 0.0033) with the response to TNFi when available data from previous studies were combined in the meta-analysis.

CONCLUSION

Our data suggest that the rs12081765, rs1532269, rs17301249 and rs7305646 genetic variants do not have a role as genetic predictors of TNFi treatment outcomes.