Background Although the use of biological agents (BA) for the treatment of psoriasis is widespread in clinical practice, studies on its persistence over time are scarce.

Purpose To estimate the persistence of treatment with BA in patients diagnosed with psoriasis receiving their first biological treatment (FBT).

Material and methods A retrospective observational study of all patients diagnosed with psoriasis who initiated FBT since its commercialisation until August 2011 (at least 5 years of follow-up) was conducted. Variables: age, sex, treatment start and discontinuation date, PASI (psoriasis area severity index) and reason for discontinuation. Persistence was defined as time (days) from the start of treatment until its discontinuation for periods greater than 3 months to include optimisation regimen. Persistence was calculated with Kaplan–Meier survival curves (log rank test).

Results 132 patients (56.8% men) were included. 7.6% (n=10), 16.7% (n=22), 25% (n=33), 46.2% (n=61) and 4.5% (n=6) received FBT with infliximab, efalizumab (until its market withdrawal), adalimumab, etanercept and ustekinumab, respectively. Mean age was 44.61 years (SD=14.5). Median overall persistence was 239 days (95%CI 181.3–296.7). Persistence for infliximab was 339 days (95% CI 0.0–780.61), efalizumab 184 days (95% CI 43.8–324.2), adalimumab 337 days (95% CI 26.4–388.7), etanercept 176 days (95% CI 177,5–234,5) and ustekinumab 350 days (95% CI 0.0–880.0). No significant differences were found for median persistence between FBT (p=0.121). 3% of patients continued, 94% discontinued and 3% were lost to follow-up.

Mean PASI at the beginning (90 unknown) was 14.5 (SD=6.6) and at the discontinuation date (84 unknown) was, for clinical improvement/remission, 0.4 (SD=1) and for the remainder, 9.2 (SD=6,9).

Conclusion Median overall persistence was low (less than a year). Persistence was approximately 1 year for infliximab, adalimumab and ustekinumab and 6 months for efalizumab and etanercept. These outcomes could indicate they are not well tolerated or ineffective. However, the main reason for discontinuation was clinical improvement/remission, followed by failure.

References and/or acknowledgements To everyone in the Department of Pharmacy who have collaborated in the collection of data and analysis.

No conflict of interest