Novel Therapeutic Targets in Rheumatoid Arthritis

Development and Validation of Adherence Score for Subcutaneous Biologic Disease-Modifying Antirheumatic Drugs

Background: The biologic disease-modifying antirheumatic drugs (bDMARDs) are currently incorporated as part of the pharmacotherapy management of inflammatory arthritis (IA). Adherence to bDMARDs is crucial to ensure treatment success in IA. However, most of the recent studies evaluated adherence level in patients using subcutaneous injections of bDMARDs utilized the indirect methods adapted from adherence assessment for oral medication. Aim: This study aimed to develop a questionnaire to assess adherence to the self-injectable subcutaneous bDMARDs. Methods: The development of the Subcutaneous bDMARDs Adherence Score (SCADS) involved evaluation of content validity. Literature reviews provide the basis for domain identification and item formation. Four experts evaluated the instrument by using a four-point ordinal scale with a rubric scoring on relevance, importance, and clarity of each item in measuring the overarching construct. The item-level content validity index (I-CVI) and the scale-level content validity index (S-CVI) were calculated. The factor structure and internal consistency reliability of SCADS were estimated using principal component analysis (PCA) and Cronbach's alpha, respectively. Results: Both S-CVI/UA (universal agreement) and the average item-level content validity index (S-CVI/Ave) (average) for the entire instrument showed excellent criteria with a value of >0.90. Cronbach's alpha coefficient value for SCADS was 0.707 indicating good internal consistency. All items showed corrected item-total correlation coefficients above 0.244. Questionnaire items with a factor loading of 0.30 or above were considered in the final factor solution. The factor analysis resulted in 3-factor solutions, which corresponded to 66.62% of the total variance. Conclusion: The SCADS is a consistent and reliable instrument for evaluating adherence among IA patients using the subcutaneous bDMARDs. It is simple to use, yet comprehensive but still requiring further clinical and international validation.

Anti-inflammatory Ellagitannins from Cleidion brevipetiolatum for the Treatment of Rheumatoid Arthritis

Six new ellagitannins, brevipetins B-G (5 and 7-11), and a new phenolic glucoside, brevipetin A (4), along with six known compounds were isolated from the traditional Chinese medicinal plant Cleidion brevipetiolatum. Their structures and absolute configurations were determined by spectroscopic analyses, chemical methods, and TD-DFT-ECD calculations. Compounds 5-11 exhibited NO inhibitory effects with IC₅₀ values of 1.9-8.2 μM, and 9 showed the most potent inhibitory effect (IC₅₀: 1.9 μM). An in vivo anti-inflammatory assessment of 9 showed that it exerts therapeutic effects in both the carrageenan-induced rat paw edema and collagen-induced arthritis (CIA) models at 50 mg/kg oral administration. The enhanced protein and mRNA expression levels of iNOS (inducible nitric oxide synthase) and COX-2 (cyclooxygenase-2) in LPS-stimulated RAW 264.7 cells were dose-dependently suppressed by 9. An anti-inflammatory mechanistic study revealed that 9 suppressed NF-κB activity by inhibiting IκBα phosphorylation and blocking translocation of p65 from the cytosol to the nucleus. Therefore, 9 might have the potential to be developed as a lead compound for relieving rheumatoid arthritis.

Helminth-based therapies for rheumatoid arthritis: A systematic review and meta-analysis

OBJECTIVE

Proteins from parasitic worms have been posed as novel therapies for rheumatoid arthritis (RA) and other auto-inflammatory diseases. However, with so many potential therapeutics, it is important that drug discovery be based on the specific phyla or species which show the most promising effects. Therefore, the aim of this systematic review and meta-analysis was to evaluate the reported effects of helminthic secretory proteins and derivative therapy on RA in an animal model.

METHODS

Medline, Scopus and Web of Science were searched to identify studies evaluating helminthic therapy in the collagen-induced arthritis model of RA. A meta-analysis was undertaken to determine the overall effect of the proteins. Subgroup analyses were also undertaken to investigate individual treatments.

RESULTS

Seven articles were included in the analysis. Overall, helminthic therapy significantly reduced arthritis score (SMD -1.193, 95% CI -1.525, -0.860). Subgroup analyses found a significant reduction in arthritis score following treatment with helminth protein ES-62 (SMD -1.186, 95% CI -1.633, -0.738) and phosphorylcholine-based treatment (SMD -0.997, 95% CI -1.423, -0.571). Subgroup analyses found ES-62 treatment significantly decreased IFN-γ levels (SMD -1.611, 95% CI -2.734, -0.487) and significantly increased levels of IL-10 (SMD 0.946, 95% CI 0.127, 1.765).

CONCLUSIONS

Therapeutics from parasitic worms are a promising avenue for drug discovery, especially with all included studies reporting a significant improvement in arthritis score. Based on pooled data presented in this study, the nematode Acanthocheilonema viteae seems to be of particular interest for therapeutics.