Dose Modification in Biologic Therapy for Moderate to Severe Psoriasis: A Descriptive Analysis in a Clinical Practice Setting.

INTRODUCTION: In biologic therapy, dose modification in carefully selected patients when psoriasis is in remission could reduce treatment costs and the risks associated with drug exposure. MATERIAL AND METHODS: Observational, descriptive, crosssectional study, performed in January 2014, of 112 patients with moderate to severe psoriasis who had been on biologic therapy for at least 6 months. The therapeutic objective in all cases was to achieve and maintain a 75% reduction in Psoriasis Area and Severity Index (PASI 75). All the patients had started treatment with the standard regimen. During treatment, the dose had been reduced in patients who achieved the therapeutic objective and escalated in those who failed to respond adequately to standard doses. RESULTS: At the time of the study, 42.9% of the patients were receiving the standard dose, 50% were on a reduced dose, and 7.1% were on an escalated regimen. The agent with which the dose was most often reduced was adalimumab (57.7%), and the agents with which therapy was most often escalated were ustekinumab (17.9%) and infliximab (12.5%). Patients who received reduced doses had significantly longer-standing disease (P=.049) and longer treatment duration with the same biologic agent (P=.009). In the group that did not fulfill the criteria for dose reduction, the proportion of patients with psoriatic arthritis was significantly higher (P=.023). Cost savings were as follows: 21.5% with adalimumab, 13.8% with etanercept, .9% with ustekinumab, and .55% with infliximab. CONCLUSIONS: Patients with longer-standing disease and longer treatment duration with the same biologic agent were significantly more likely to be candidates for dose reduction. The proportion of patients with psoriatic arthritis was greater in the group of patients who did not fulfill the conditions for dose reduction. The overall cost saving achieved using the dose modification algorithm described in this study was 13%. Controlled studies are needed to define the profile of the patients best suited for dose reduction strategies without loss of treatment efficacy.