Post-marketing safety study demonstrates the safety and efficacy of baricitinib in moderate-to-severe RA patients

The findings of a 24-week post-marketing safety study, recently published in Rheumatology and Therapy, reported that baricitinib was generally well tolerated in Chinese patients with moderate-to-severe active rheumatoid arthritis (RA), and its safety profile was consistent with previous studies. No new safety signals were identified. Additionally, the effectiveness of baricitinib was promising, with over half of the evaluated patients achieving disease activity score with 28 joints/c-reactive protein (DAS28-CRP) remission at 24 weeks. 

 Wu et al. conducted a post-marketing safety study involving 667 Chinese adult patients with moderate-to-severe active RA who received baricitinib for 12-24 weeks. By week 12, 214 patients (32.1%) experienced adverse events (AEs), with an exposure-adjusted incidence rate (EAIR) of 172.5 per 100 patient-years. Among them, 22 (3.3%) experienced serious AEs, with an EAIR of 15.0. By week 24, AEs occurred in 250 patients (37.5%), with an EAIR of 125.9, including 28 patients (4.2%) with serious AEs and an EAIR of 10.9. Two patients (0.3%) succumbed to death, one due to pneumonia and the other due to an unknown cause, resulting in a death EAIR of 0.77. 

Serious infection occurred in 1.2% of patients, with an EAIR of 3.1, while hepatotoxicity occurred in 3.4% of patients, with an EAIR of 9.0. No patients met the potential Hy’s law laboratory criteria (alanine/aspartate aminotransferases ≥ 3 × upper limit of normal (ULN) and total bilirubin ≥ 2 × ULN), and only one patient experienced malignancy. Additionally, no patients experienced venous thromboembolism or major adverse cardiovascular events. By week 24, 52.4%, 27.5%, and 27.6% of patients achieved remission according to DAS28-CRP, Simplified Disease Activity Index (SDAI), and Clinical Disease Activity Index (CDAI), respectively. 

Taylor et al. conducted a 24-week post-marketing surveillance study involving 3770 patients with RA. The study found that the safety and effectiveness profile of baricitinib in the Japanese population was comparable to that observed in the global RA population. No new safety signals were detected. 

The current post-marketing safety study underscores the potential of baricitinib as a valuable therapeutic option for moderate-to-severe RA patients, offering a well-tolerated and effective long-term treatment strategy. Further research and clinical trials are warranted to better understand the optimal dosing regimens and potential benefits of baricitinib in the treatment of RA.  

 References 

  1. Wu CY, Wang Q, Shi J, Zhang XY, Du R, Gu JR, et al. Safety and Effectiveness of Baricitinib in Chinese Patients with Moderate-to-Severe Rheumatoid Arthritis: 24-Week Results from a Post-Marketing Safety Study. Rheumatol Ther. 2023 Sep 28. 
  1. Taylor PC, Takeuchi T, Burmester GR, Durez P, Smolen JS, Deberdt W, et al. Safety of baricitinib for the treatment of rheumatoid arthritis over a median of 4.6 and up to 9.3 years of treatment: final results from long-term extension study and integrated database. Ann Rheum Dis. 2022 Mar;81(3):335–43.