Category: Professional Posters
Purpose: The incredibly high cost and inevitable side effects of specialty drugs in the treatment of plaque psoriasis and psoriatic arthritis continue to present challenges for managed care organizations. Currently, ustekinumab (Stelara) is the last line agent. Medication utilization evaluation can help determine the appropriate use of ustekinumab for plaque psoriasis or psoriatic arthritis as substantial variance may occurs between dermatologists and rheumatologists in terms of treatment plans. The objective of this study is to compare the prescribing trend of ustekinumab between dermatologists and rheumatologists and to evaluate physician adherence to Kaiser Permanente's drug guidelines for plaque psoriasis and psoriatic arthritis.
Methods: The study was a retrospective chart review of 24 adult patients who have received a prescription for ustekinumab from January 2015 to August 2018 for the treatment of plaque psoriasis or psoriatic arthritis at Kaiser Permanente Downey Medical Center. Patient charts were reviewed using the Health Connect electronic medical record system. Age, gender, types of prescriber, and prescription drugs for plaque psoriasis or psoriatic arthritis were extracted from patient charts. Exclusion criteria include patients who are deceased, were pregnant at any point after diagnosis of plaque psoriasis or psoriatic arthritis, or are no longer active at Kaiser Permanente. Medication use evaluation and structural chart reviews were used to determine the adherence of physician prescribing patterns of ustekinumab with the current stepwise therapy for the treatment of plaque psoriasis or psoriatic arthritis under Kaiser Permanente drug guideline.
Results: Out of the 28 patients reviewed, 24 subjects were included. There was a greater number of patients diagnosed with plaque psoriasis (n=20, 83.3%) compared to psoriatic arthritis (n=10, 41.7%) with 6 patients diagnosed with both plaque psoriasis and psoriatic arthritis. There were a total of 12 patients that did not meet the minimum criteria in order to be initiated ustekinumab. Out of the 12 patients, 10 patients (83.3%) using ustekinumab that were not adherent to Kaiser Permanente’s drug guideline were prescribed by dermatologists (p=0.81). Dermatologists appeared to be prescribing ustekinumab more to the older population (>45 years of age) while rheumatologists were prescribing more to the younger population ( < 45 years of age). It also observed that many of the biologics were only utilized for a short period of time (approximately 1 to 2 years) before switching to another agent. However, there is no significant difference between dermatologists and rheumatologists in terms of prescribing adherence to the Kaiser Permanente drug guideline.
Conclusion: This study was limited by not being able to reach power for statistical significance due to small subject size. However, it is observed that there is no significant difference between dermatologists and rheumatologists in terms of prescribing habit and adherence to the Kaiser Permanente's drug guideline. Next step is to discuss with the chief of service the results and to initiate physician education if appropriate.