Laura Ferris, MD, PhD
Biologic therapy is generally reserved for patients with more moderate-to-severe psoriasis, often defined as BSA ≥10% or PASI of ≥10. Notably, these criteria are all clinician-performed. The Dermatology Life Quality Index (DLQI) measures the impact of the disease on the patient with a score of 0-5, 6-10, and 11-30 indicating mild, moderate, and severe disease, respectively. In a cross-sectional, observational study, 72.4% of psoriasis patients who qualified for systemic therapy initiation based on PASI and/or BSA had a DLQI of less than 10. Conversely, 10.4% of patients with a DLQI score higher than 10 did not qualify for systemic therapy based on PASI and/or BSA. This study highlights the complementary value of considering both clinician and patient determinants of disease severity when choosing a psoriasis therapy (Barbieri JS et al.)
With so many therapeutic options, it is increasingly common for patients to switch from one biologic to another. Many factors that go into the decision to switch therapies. A retrospective study of 115 adult patients with psoriasis found that the primary factor driving switching was lack of sufficient efficacy in treating skin disease. Having concomitant psoriatic arthritis increased the likelihood of switching by 2.69-fold (Akdogan N et al.). These findings suggest that shared decision making with dermatology, rheumatology, and the patient may help in choosing a treatment plan that best addresses both skin and joints.
One consideration when counseling patients about their likelihood of response to a second or third biologic is that in several clinical trials, biologic-naïve patients tend to have higher PASI responses to biologics than do heavier and biologic-experienced patients. A recent retrospective study found that receiving one or more biologic receiving was associated with a lower likelihood of achieving a PASI75 response to guselkumab (Hung YT et al.). However, in a real-life multicenter study including 57 adult patients with moderate-to-severe psoriasis receiving risankizumab, more biologic-experienced patients reached PASI 100 at weeks 36 and 52 (71.8% and 69.2%, respectively) compared with biologic-naïve patients (50.0% and 37.5%, respectively) (Gerdes S et al.). While both studies were small and no firm conclusions or comparisons can be drawn, real-world data from large multicenter studies that evaluate multiple therapies may guide us in choosing the best therapy for challenging patients who are often underrepresented in clinical trials. Understanding how switching within vs. between classes (TNF, IL-17, and IL-23 inhibitors) impacts efficacy will also help in making choices about biologic switches.