Treatment patterns and costs for anti-TNFα biologic therapy in patients with psoriatic arthritis

BACKGROUND: Real-world data regarding anti-tumor necrosis factor alpha (anti-TNFα) biologic therapy use in psoriatic arthritis (PsA) are limited; therefore, we described treatment patterns and costs of anti-TNFα therapy in PsA patients in the United States. METHODS: PsA patients (N = 990) aged ≥18 years who initiated anti-TNFα therapy were selected from MarketScan claims databases (10/1/2009 to 9/30/2010). Number of patients on first- (n = 881), second- (n = 72), or third- or greater (n = 37) line of anti-TNFα therapy, persistence, time-to-switch or modification, pharmacy and medical costs (measured per patient per month [PPPM]) for each line of therapy were observed during the 3-year follow-up. RESULTS: PsA patients receiving only one line of anti-TNFα therapy remained on first-line for ~17 months while those who switched to second- or third- or greater persisted on first-line for ~11 to 12 months, respectively. Time to first-line modification was longer for patients who switched to third- or greater line therapy (7 months) than those who did not switch or switched to second-line (range, ~2 to 4 months). Time-to-switch and time to first-line modification was progressively shorter with each line of therapy for patients who received third- or greater line. PPPM medical costs were higher for patients who did not switch ($322) than those who switched to second- ($167) or third- or greater ($217) line. PPPM pharmacy costs were greater for patients with third- or greater line therapy ($2539) than those who did not switch ($1985) or switched to second-line ($2045). CONCLUSION: While the majority of patients received only one line of anti-TNFα therapy, a subset of patients switched to multiple lines of therapy during the 3-year follow-up period. Persistence and therapy modifications differed between these patients and those receiving only one line. Overall medical costs were highest for patients who did not switch, and pharmacy costs increased as patients switched to each new line of therapy.