Palindromic rheumatism is a condition characterized by intermittent episodes of joint inflammation with acute attacks lasting a few days that resolve spontaneously. However, approximately half of people with this condition go on to develop rheumatoid arthritis, a chronic disease that causes irreversible joint damage, especially in those who have biomarkers such as rheumatoid factor and anti-citrullinated protein antibodies. Until now, with no clinical trials available, the usual strategy was to treat patients with hydroxychloroquine, with the aim of improving the symptoms of the disease.
In this context, the team led by Raimon Sanmartí, head of the IDIBAPS Inflammatory joint diseases (IJDs) research group, led a two-year clinical trial with 70 patients with palindromic rheumatism, to compare the efficacy of hydroxychloroquine with abatacept, a drug that acts by modulating the immune system through the inhibition of lymphocytes, to reduce the progression towards rheumatoid arthritis. The study was published in the Nature Medicine journal.
The results of the study are clear: treatment with abatacept very significantly reduces the progression to rheumatoid arthritis. With this drug, only 20% of patients go on to develop arthritis, compared to 50% of those treated with hydroxychloroquine. Furthermore, patients treated with abatacept not only avoid progression in rheumatoid arthritis, but also show a significant improvement in the symptoms of palindromic rheumatism, with a higher frequency of complete remission of flare-ups and less intense inflammatory episodes. Both drugs were safe and well tolerated.
“The results of this study indicate that we can intervene early to modify the natural course of the disease and reduce the risk of patients developing more severe and irreversible diseases,” explains Raimon Sanmartí. “This opens the door to a paradigm shift in the treatment of these patients.”
The study, involving several national centres, also features Isabel Haro as a principal co-investigator. She is head of the Unit for the Synthesis and Biomedical Applications of Peptides (USiBAP) at the Institute of Advanced Chemistry of Catalonia (IQAC-CSIC). In these patients, the evolution of several biomarkers (autoantibodies) developed by the CSIC research group was also studied over the course of the follow-up. According to Isabel Haro, “Although no significant differences were observed between abatacept and hydroxychloroquine in the response of autoantibodies, this work demonstrates the value of immunomodulatory approaches in the early stages of the disease, when it is still possible to prevent progression to more severe and chronic forms.”
Rheumatoid arthritis is a disease that affects patients’ quality of life and represents a significant burden on healthcare systems. Being able to prevent its development in a significant proportion of cases represents an important advance in the management of rheumatic diseases.
Study of reference
Sanmarti, R., Pérez-García, C., de-Toro, F.J. et al. Abatacept versus hydroxychloroquine for prevention of rheumatoid arthritis in individuals with palindromic rheumatism: a randomized open-label trial. Nat Med (2026). https://doi.org/10.1038/s41591-026-04395-6
