NPF and IPC Reassess TB Testing for IL-17 and IL-23 Inhibitors
A new joint statement from the NPF and IPC re-evaluates the necessity of TB testing for patients using specific biologic therapies.
The NPF and IPC's joint statement questions routine TB testing for IL-17 and IL-23 inhibitors.
Experts agree that testing is still necessary in endemic regions and for patients on TNF inhibitors.
JAK inhibitors present a significant risk for TB reactivation, warranting screening.
A recent joint statement from the National Psoriasis Foundation (NPF) and the International Psoriasis Council (IPC) has sparked a discussion regarding the necessity of tuberculosis (TB) testing for patients being treated with interleukin (IL)-17 and IL-23 inhibitors. This statement does not impose a blanket prohibition on testing; rather, it provides guidance on when screening may still be appropriate, particularly in endemic regions and for patients on other biologic therapies.
The statement was co-authored by Andrew Blauvelt, MD, MBA, and Joseph F. Merola, MD, MMSc, both prominent figures in dermatology. Blauvelt noted that the NPF Medical Board, consisting of approximately 35 members from the US and Canada, unanimously approved the statement. Among the IPC experts, 87% supported the statement while 13% opposed it, primarily from regions where TB is endemic and routine testing is standard practice before initiating biologic treatments.
Blauvelt emphasized that in areas where TB is prevalent, testing remains a reasonable precaution, especially when dermatologists are the primary care providers. He likened the necessity of TB testing to routine checks for blood pressure or lipid levels as part of comprehensive patient care. Importantly, he highlighted that IL-17 and IL-23 inhibitors do not significantly increase the risk of TB reactivation, drawing a parallel to doxycycline, which does not require TB screening even in high-risk areas.
Merola expanded on the implications of the statement beyond dermatology, particularly in rheumatology, where TB testing is often reflexive due to the widespread use of TNF inhibitors. He pointed out that while low-dose methotrexate carries a minimal risk of reactivation, the statement specifically addresses the use of IL-17 and IL-23 inhibitors, advocating for case-by-case decision-making. The response from audiences and residents has been overwhelmingly positive, as they appreciate the reduction in delays caused by the need for TB test results.
In discussing other therapeutic agents, Merola noted that JAK inhibitors pose a significant risk for TB reactivation, making screening essential. While the risk associated with leflunomide in combination therapies for psoriatic arthritis is less clearly defined, some studies suggest a potential link, indicating that screening should be considered. He also mentioned azathioprine as another agent that may carry some risk. The statement's foundation is rooted in both clinical data and the mechanisms of these therapies, highlighting the nuanced approach required in managing patient care.
