A JAAD Letter Says Psoriasis Biologic Monitoring Has Gaps. What Kind of Evidence Backs That Claim?

A letter from Yangyu Xu and Liyun Zhang, titled "Toward a more nuanced approach: Unaddressed gaps in monitoring recommendations for psoriasis biologics," appeared online ahead of print on April 21, 2026, and is slated for the October 2026 print issue of the Journal of the American Academy of Dermatology (volume 95, issue 4). The title's phrasing and brevity mark it as a commentary responding to existing guidance rather than a study built on new patient data, a distinction that matters for how much weight its "gaps" claim can actually carry.

The guidance it is pushing against is five years old. The Joint AAD-NPF guideline, published by Menter and colleagues in 2019, set the baseline that most dermatologists still follow: a tuberculosis test and hepatitis B and C serologies before starting a biologic, routine CBC and metabolic panels, and drug-specific intervals for TNF inhibitors (four weeks, twelve weeks, then every three to six months). That guideline predates risankizumab's 2019 expansion into routine use, deucravacitinib's 2022 approval, and bimekizumab's 2023 launch. The American Academy of Dermatology and National Psoriasis Foundation are not expected to issue a full revision until 2027, leaving roughly a year in which clinicians are relying on literature commentary, not updated consensus, to fill in monitoring questions for the newest drugs.

That literature has split into two camps in the past year. Michael Lebwohl's "To test or not to test?" series, most recently updated in a 2026 JAAD piece, argues that most baseline and ongoing screening (HIV, hepatitis, CBC, metabolic panels) adds little for biologic-treated psoriasis patients, and that TB screening is the only test with solid evidentiary support. A 2025 review in the Journal of Dermatological Treatment by Fenkel, Osborne, Armstrong, Strober, Stein Gold, Cameron, and Lebwohl takes the opposite tack, laying out prescribing-information-based, agent-by-agent monitoring advice. Xu and Zhang's letter sits between those positions, arguing neither resolves the gaps for real-world prescribing.

The strongest concrete example of what a gap looks like comes from bimekizumab's own trial program. Pooled two-year safety data published in JAAD found a hepatic adverse event rate of 3.5 per 100 patient-years, in line with placebo, adalimumab, secukinumab, and ustekinumab, and the authors proposed a specific stopping rule: recheck liver enzymes twice weekly if elevated, and discontinue if levels reach three times the upper limit of normal and twice baseline for two weeks running. That kind of drug-specific threshold does not appear anywhere in the 2019 AAD-NPF guideline, because the drug did not exist when the guideline was written.

A single case report sharpens the same point for a different drug class. A report describing risankizumab use in a liver transplant patient found that monitoring needs diverged sharply from the blanket "no routine labs needed" framing that IL-23 inhibitors typically get in guideline language. One case cannot establish a general monitoring protocol, but it illustrates exactly the kind of comorbid subgroup that population-level guidance tends to leave out.

The gap runs in both directions, which is where the debate gets more interesting than a simple call for more testing. A cross-sectional audit of 100 patients, published in JEADV Clinical Practice by Howard-James and Gilhooley, found that routine six-monthly monitoring as currently practiced carries real costs in clinic time, lab resources, and patient blood draws, with no clear evidence those draws are catching anything actionable in most patients. So the open question is not only whether current guidance misses newer drugs, but whether the existing testing cadence for older ones is itself doing more than the data support.

What the Xu-Zhang letter does not appear to touch, based on the surrounding literature it sits within, is biosimilar switching: whether moving a patient from an originator biologic to a biosimilar resets any of these monitoring clocks. It is a narrow, practical question that neither the 2019 guideline, the Lebwohl series, nor the Fenkel review addresses directly, and it is the kind of detail that tends to surface only once a formal body revisits its recommendations, which for psoriasis biologics is not scheduled until 2027.