Therapy with disease-modifying antirheumatic drugs (DMARDs) increases the already higher risk of herpes zoster (shingles) in patients with rheumatoid arthritis. Among the various DMARDs, the risk is highest for Janus kinase inhibitors, (JAK inhibitors). This is shown by data from the RABBIT registry recently presented at the EULAR 2020.
Varicella-zoster reactivation occurs two to three times more frequently in patients with rheumatoid arthritis than in healthy people, solely due to the disease.1 Immunosuppressants further increase this risk. Various studies, for example on TNF-α blockers, have already described this problem.
In order to be able to assess the safety and effectiveness of DMARD therapy in these patients, data on medication and side effects are collected in Germany in the so-called "Biologics Register" RABBIT.2 During the virtual European Congress for Rheumatology EULAR 2020, Dr. Strangfeld from the Charité University Hospital in Berlin presented current data from the register.3,4
The analysis included data from 12,470 individuals who had been added to the register between 2007 and 2019. 433 test persons suffered one or more herpes zoster infections during this period (452 cases in total). The disease was severe in 52 people.
Patients who received JAK inhibitors had the highest risk of herpes zoster (25 cases / 1,000 patient-years), those who received conventional synthetic DMARDs such as methotrexate had the lowest risk (5.8 cases / 1,000 patient-years). Among biological DMARDs such as TNF-α inhibitors and other biologicals, zoster reactivation occurred in 8.5-10.4 cases / 1,000 patient-years.
Herpes zoster can severely limit the quality of life of those affected. The inactivated vaccine (killed vaccine), available since 2018, makes it easier to protect people with rheumatoid arthritis and immunosuppressive therapy from zoster reactivation. The author, therefore, recommends the systematic vaccination of this risk group.
Sources:
1. Harigai M. Growing evidence of the safety of JAK inhibitors in patients with rheumatoid arthritis. Rheumatology (Oxford). 2019;58(Suppl 1):i34-i42. doi:10.1093/rheumatology/key287
2. Only in German: RABBIT - Rheumatoid Arthritis: Monitoring of Biologics Therapy, https://biologika-register.de/
3. Anja Strangfeld et al, Risk of herpes zoster in patients with rheumatoid arthritis under biological, targeted synthetic, and conventional synthetic DMARD treatment. Abstract N°: 3171. EULAR 2020. https://biologika-register.de/wp-content/uploads/2020/06/A54_HerpesZoster_EULAR_2020.pdf
4. EULAR Congress News, Friday/Saturday EDITION. Shingles risk appears highest with JAK-inhibitor treatment for rheumatoid arthritis, p. 12. https://www.eularcongressnews-digital.com/eularcongressnews/eular_2020_fri_sat_june_5_6?pg=12#pg12