Monitoring drug levels may be a useful tactic for directing the therapeutic strategy in patients with psoriasis, according to a study published in the September issue of JAMA Dermatology.1
Monoclonal antibodies have shown great efficacy at treating psoriasis and, specifically,this recent study indicates that adequate and early treatment exposure to ustekinumab (Janssen Immunology), which targets IL-12 and IL-23, may positively inf luence clinical outcome. Researchers found a statistically significant association between early drug levels and six-month Psoriasis Area and Severity Index (PASI) 75 response in patients with psoriasis taking ustekinumab.
Ustekinumab therapy is weight-based with patients >100 kg receiving 90 mg and patients <100 kg receiving 45 mg. It is postulated that treatment failure in patients may be related to sub-therapeutic dosing of this medication. In this study, Teresa Tsakok, M.A., MRCP, and colleagues from the St John's Institute of Dermatology in London examined the association between drug level and response on the same day the drug level was measured, as well as the association between early drug level and response at six months.
The authors invited all UK adults who fulfilled inclusion criteria for the Biomarkers of Systemic Treatment Outcomes in Psoriasis study, and who were enrolled in the British Association of Dermatologists Biologic and Immunomodulators Register to participate. Clinical response to ustekinumab was assessed longitudinally using PASI scoring. Blood samples were collected between June 2009 and December 2016 to measure levels of ustekinumab and anti-drug antibodies.
1. Tsakok T, Wilson N, Dand N, et al. Association of Serum Ustekinumab Levels With Clinical Response in Psoriasis. JAMA Dermatol. 2019;155(11):1235-43.