Objective: CT-P13, a biosimilar of infliximab, is widely used for treating ankylosing spondylitis (AS). However, the formation of anti-drug antibodies (ADAs) can reduce its efficacy. This study aimed to identify risk factors associated with high ADA levels in AS patients treated with CT-P13. Methods: A prospective observational study enrolled patients with intravenous CT-P13. Clinical data and disease activity was assessed at baseline, 24 weeks, and 54 weeks after CT-P13 treatment. Blood concentrations of CT-P13 and ADAs were measured at 24 and 54 weeks, and their correlation was investigated. Patients were grouped by ADA levels at 54 weeks. Univariable and multivariable logistic regression identified factors associated with high ADA concentrations. Results: A total of 34 patients was enrolled. Significant decreases in Bath Ankylosing Spondylitis Disease Activity Index and Bath Ankylosing Spondylitis Functional Index scores were observed relative to baseline after 24 weeks of CT-P13 therapy. Serum concentrations of CT-P13 and ADA levels increased following treatment. The median serum CT-P13 concentration was 17.6 [12.8, 22.7] µg/mL at 24 weeks and 23.5 [11.7, 34.2] µg/mL at 54 weeks. ADA levels were 6.7 [6.5, 9.1] AU/mL at 24 weeks and 11.4 [9.0, 28.4] AU/mL at 54 weeks. The serum concentrations of CT-P13 and ADA exhibited a negative correlation. In multivariable analysis, current smoking was associated with high ADA production at 54 weeks. Conclusion Smoking is identified as a significant risk factor for elevated ADAs in AS patients treated with CT-P13. The findings underscore the importance of smoking-cessation strategies in the management of AS patients.

Objective: CT-P13, a biosimilar of infliximab, is widely used for treating ankylosing spondylitis (AS). However, the formation of anti-drug antibodies (ADAs) can reduce its efficacy. This study aimed to identify risk factors associated with high ADA levels in AS patients treated with CT-P13. Methods: A prospective observational study enrolled patients with intravenous CT-P13. Clinical data and disease activity was assessed at baseline, 24 weeks, and 54 weeks after CT-P13 treatment. Blood concentrations of CT-P13 and ADAs were measured at 24 and 54 weeks, and their correlation was investigated. Patients were grouped by ADA levels at 54 weeks. Univariable and multivariable logistic regression identified factors associated with high ADA concentrations. Results: A total of 34 patients was enrolled. Significant decreases in Bath Ankylosing Spondylitis Disease Activity Index and Bath Ankylosing Spondylitis Functional Index scores were observed relative to baseline after 24 weeks of CT-P13 therapy. Serum concentrations of CT-P13 and ADA levels increased following treatment. The median serum CT-P13 concentration was 17.6 [12.8, 22.7] µg/mL at 24 weeks and 23.5 [11.7, 34.2] µg/mL at 54 weeks. ADA levels were 6.7 [6.5, 9.1] AU/mL at 24 weeks and 11.4 [9.0, 28.4] AU/mL at 54 weeks. The serum concentrations of CT-P13 and ADA exhibited a negative correlation. In multivariable analysis, current smoking was associated with high ADA production at 54 weeks. Conclusion Smoking is identified as a significant risk factor for elevated ADAs in AS patients treated with CT-P13. The findings underscore the importance of smoking-cessation strategies in the management of AS patients.

Background/Aims: Exercise is a key component of the management of axial spondyloarthritis (axSpA), providing symptomatic relief and helping prevent ankylosis. However, there is a lack of quantitative studies evaluating daily exercise patterns in patients with axSpA. This study assessed the types, frequency, and duration of exercises performed by these patients through a structured questionnaire. Methods: This cross-sectional study included radiographic axSpA patients who visited a rheumatology clinic between September 2014 and March 2016 and provided informed consent to participate. The survey captured information on four types of exercise: high-intensity exercise, moderate-intensity exercise, strength training, and walking. Disease activity and functional status were evaluated using the Bath ankylosing spondylitis disease activity index (BASDAI) and the Bath ankylosing spondylitis functional index (BASFI), respectively. Results: A total of 645 patients participated in the study. Among them, 25.1% engaged in high-intensity exercise, 36.0% in moderate-intensity exercise, 81.2% in walking, and 32.8% in strength training. The median weekly exercise frequency was 3.0 days (interquartile range [IQR], 2.0-4.0) for high-intensity exercise, 3.0 days (IQR, 2.0-5.0) for moderate-intensity exercise, 5.5 days (IQR, 4.0-7.0) for walking, and 3.0 days (IQR, 2.0-5.0) for strength training. The median daily exercise duration was 60 minutes (IQR, 60-120) for high-intensity exercise, 60 minutes (IQR, 30-90) for moderate-intensity exercise, 30 minutes (IQR, 20-60) for walking, and 30 minutes (IQR, 20-60) for strength training. Comparisons by disease activity showed that BASFI scores were more strongly associated with differences in exercise patterns than BASDAI scores. Conclusion Radiographic axSpA patients predominantly engaged in low-intensity activities, particularly walking, typically for short durations. Given the observed variations in exercise patterns based on disease activity, personalized exercise education and guidance should be prioritized in clinical practice to optimize axSpA management.

Background/Aims: Exercise is a key component of the management of axial spondyloarthritis (axSpA), providing symptomatic relief and helping prevent ankylosis. However, there is a lack of quantitative studies evaluating daily exercise patterns in patients with axSpA. This study assessed the types, frequency, and duration of exercises performed by these patients through a structured questionnaire. Methods: This cross-sectional study included radiographic axSpA patients who visited a rheumatology clinic between September 2014 and March 2016 and provided informed consent to participate. The survey captured information on four types of exercise: high-intensity exercise, moderate-intensity exercise, strength training, and walking. Disease activity and functional status were evaluated using the Bath ankylosing spondylitis disease activity index (BASDAI) and the Bath ankylosing spondylitis functional index (BASFI), respectively. Results: A total of 645 patients participated in the study. Among them, 25.1% engaged in high-intensity exercise, 36.0% in moderate-intensity exercise, 81.2% in walking, and 32.8% in strength training. The median weekly exercise frequency was 3.0 days (interquartile range [IQR], 2.0-4.0) for high-intensity exercise, 3.0 days (IQR, 2.0-5.0) for moderate-intensity exercise, 5.5 days (IQR, 4.0-7.0) for walking, and 3.0 days (IQR, 2.0-5.0) for strength training. The median daily exercise duration was 60 minutes (IQR, 60-120) for high-intensity exercise, 60 minutes (IQR, 30-90) for moderate-intensity exercise, 30 minutes (IQR, 20-60) for walking, and 30 minutes (IQR, 20-60) for strength training. Comparisons by disease activity showed that BASFI scores were more strongly associated with differences in exercise patterns than BASDAI scores. Conclusion Radiographic axSpA patients predominantly engaged in low-intensity activities, particularly walking, typically for short durations. Given the observed variations in exercise patterns based on disease activity, personalized exercise education and guidance should be prioritized in clinical practice to optimize axSpA management.

Background/Aims: Exercise is a key component of the management of axial spondyloarthritis (axSpA), providing symptomatic relief and helping prevent ankylosis. However, there is a lack of quantitative studies evaluating daily exercise patterns in patients with axSpA. This study assessed the types, frequency, and duration of exercises performed by these patients through a structured questionnaire. Methods: This cross-sectional study included radiographic axSpA patients who visited a rheumatology clinic between September 2014 and March 2016 and provided informed consent to participate. The survey captured information on four types of exercise: high-intensity exercise, moderate-intensity exercise, strength training, and walking. Disease activity and functional status were evaluated using the Bath ankylosing spondylitis disease activity index (BASDAI) and the Bath ankylosing spondylitis functional index (BASFI), respectively. Results: A total of 645 patients participated in the study. Among them, 25.1% engaged in high-intensity exercise, 36.0% in moderate-intensity exercise, 81.2% in walking, and 32.8% in strength training. The median weekly exercise frequency was 3.0 days (interquartile range [IQR], 2.0-4.0) for high-intensity exercise, 3.0 days (IQR, 2.0-5.0) for moderate-intensity exercise, 5.5 days (IQR, 4.0-7.0) for walking, and 3.0 days (IQR, 2.0-5.0) for strength training. The median daily exercise duration was 60 minutes (IQR, 60-120) for high-intensity exercise, 60 minutes (IQR, 30-90) for moderate-intensity exercise, 30 minutes (IQR, 20-60) for walking, and 30 minutes (IQR, 20-60) for strength training. Comparisons by disease activity showed that BASFI scores were more strongly associated with differences in exercise patterns than BASDAI scores. Conclusion Radiographic axSpA patients predominantly engaged in low-intensity activities, particularly walking, typically for short durations. Given the observed variations in exercise patterns based on disease activity, personalized exercise education and guidance should be prioritized in clinical practice to optimize axSpA management.

Objective: CT-P13, a biosimilar of infliximab, is widely used for treating ankylosing spondylitis (AS). However, the formation of anti-drug antibodies (ADAs) can reduce its efficacy. This study aimed to identify risk factors associated with high ADA levels in AS patients treated with CT-P13. Methods: A prospective observational study enrolled patients with intravenous CT-P13. Clinical data and disease activity was assessed at baseline, 24 weeks, and 54 weeks after CT-P13 treatment. Blood concentrations of CT-P13 and ADAs were measured at 24 and 54 weeks, and their correlation was investigated. Patients were grouped by ADA levels at 54 weeks. Univariable and multivariable logistic regression identified factors associated with high ADA concentrations. Results: A total of 34 patients was enrolled. Significant decreases in Bath Ankylosing Spondylitis Disease Activity Index and Bath Ankylosing Spondylitis Functional Index scores were observed relative to baseline after 24 weeks of CT-P13 therapy. Serum concentrations of CT-P13 and ADA levels increased following treatment. The median serum CT-P13 concentration was 17.6 [12.8, 22.7] µg/mL at 24 weeks and 23.5 [11.7, 34.2] µg/mL at 54 weeks. ADA levels were 6.7 [6.5, 9.1] AU/mL at 24 weeks and 11.4 [9.0, 28.4] AU/mL at 54 weeks. The serum concentrations of CT-P13 and ADA exhibited a negative correlation. In multivariable analysis, current smoking was associated with high ADA production at 54 weeks. Conclusion Smoking is identified as a significant risk factor for elevated ADAs in AS patients treated with CT-P13. The findings underscore the importance of smoking-cessation strategies in the management of AS patients.

Background/Aims: Exercise is a key component of the management of axial spondyloarthritis (axSpA), providing symptomatic relief and helping prevent ankylosis. However, there is a lack of quantitative studies evaluating daily exercise patterns in patients with axSpA. This study assessed the types, frequency, and duration of exercises performed by these patients through a structured questionnaire. Methods: This cross-sectional study included radiographic axSpA patients who visited a rheumatology clinic between September 2014 and March 2016 and provided informed consent to participate. The survey captured information on four types of exercise: high-intensity exercise, moderate-intensity exercise, strength training, and walking. Disease activity and functional status were evaluated using the Bath ankylosing spondylitis disease activity index (BASDAI) and the Bath ankylosing spondylitis functional index (BASFI), respectively. Results: A total of 645 patients participated in the study. Among them, 25.1% engaged in high-intensity exercise, 36.0% in moderate-intensity exercise, 81.2% in walking, and 32.8% in strength training. The median weekly exercise frequency was 3.0 days (interquartile range [IQR], 2.0-4.0) for high-intensity exercise, 3.0 days (IQR, 2.0-5.0) for moderate-intensity exercise, 5.5 days (IQR, 4.0-7.0) for walking, and 3.0 days (IQR, 2.0-5.0) for strength training. The median daily exercise duration was 60 minutes (IQR, 60-120) for high-intensity exercise, 60 minutes (IQR, 30-90) for moderate-intensity exercise, 30 minutes (IQR, 20-60) for walking, and 30 minutes (IQR, 20-60) for strength training. Comparisons by disease activity showed that BASFI scores were more strongly associated with differences in exercise patterns than BASDAI scores. Conclusion Radiographic axSpA patients predominantly engaged in low-intensity activities, particularly walking, typically for short durations. Given the observed variations in exercise patterns based on disease activity, personalized exercise education and guidance should be prioritized in clinical practice to optimize axSpA management.