<h3>Background:</h3> In Rheumatoid Arthritis (RA), the use of bDMARD (biological) medications is considered among the treatment options as part of the control of disease activity. Pharmacovigilance programs deals with the detection, evaluation and understanding of adverse events with the use of medications. In recent years there have been reports about the increased risk of adverse events, especially cardiovascular and thrombotic events, with JAK inhibitors. <h3>Objectives:</h3> To make a comparison of the drug adverse reactions (DAR) and drug adverse events (DAE) between JAK inhibitors and anti-TNFs in a Colombian RA population. <h3>Methods:</h3> A retrospective observational study. Pharmacovigilance (PV) data were extracted including all DAE and DAR reports from October 2021 to October 2023. Prescriptions for the two groups of medications (Anti TNFs Vs iJAK) were included in the evaluated period. The number of DAE and DAR reports was established. Causality was assessed using the WHO algorithm. DAE and DAR reporting frequencies were established. <h3>Results:</h3> Between October 2021 to October 2023, 79 reports of DAE and DAR with anti-TNF's and JAK inhibitors were found. 95% of the reports registered by the PV program were classified as mild causality, and 5% as moderate/severe, according to the WHO algorithm. There are 6 times more patients prescribed with anti-TNF than with iJAKs. In the RA cohort using iJAKs, 61% were using Tofacitinib, 29% were using Baricitinib, and 10% were using Upadacitinib. With Tofacitinib were found 4 DAEs (5.1%) associated, and 5 DARs (6.3%) of the last ones, 3 were Herpes-Zoster infections. With Baricitinib were found 5 DAEs (6.3%) and 1 DAR (1.3%). Finally, for Upadacitinib were found 1 DAEs and 1 DAR respectively. No major cardiovascular adverse events or thrombotic events were reported in patients using JAK inhibitors. Regarding anti-TNFs, 25.3% were using Certolizumab, 26.6% Etanercept, 18.3% Adalimumab, and 29.8% another anti-TNFs. With anti-TNFs were found 62 reports of DARs/DAEs (78.5%). Certolizumab (33%) and Etanercept (20%) were the biologicals with the highest frequency of reports with DAEs and DARs (Figure 1). The most frequently reported events were skin allergic reaction and gastrointestinal intolerance. Finally, only one patient reported a possibly associated major cardiovascular event during treatment with Infliximab. <h3>Conclusion:</h3> There are proportionally fewer adverse events and adverse reactions with JAK inhibitors than with anti-TNFs. No major cardiovascular events or thrombotic events were found in a great population of patients using JAKs inhibitors in recent two years. Larger studies are required in the Latin American population to confirm these results. Tofacitinib presented a number of reports of significant DARs related to skin reactions. Proportionally, the biological drug that presented the best safety profile was Adalimumab. It is necessary to establish active surveillance in the pharmacovigilance programs for cases presented especially with the use of iJAKs. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Pedro Santos-Moreno Abbvie, Abbott, Biopas-UCB, Bristol, Janssen, Pfizer, Roche, Sanofi, Abbvie, Abbott, Biopas-UCB, Bristol, Janssen, Pfizer, Roche, Sanofi, Laura Villarreal: None declared, Wilberto Rivero: None declared, Pedro Rodríguez-Linares: None declared, Fernando Rodriguez-Florido: None declared, Nicolás Gutiérrez: None declared, Gabriel-Santiago Rodríguez-Vargas: None declared, Adriana Rojas-Villarraga: None declared.