A multicentre, efficacy and safety study of methotrexate to increase response rates in patients with uncontrolled gout receiving pegloticase (MIRROR): 12-month efficacy, safety, immunogenicity, and pharmacokinetic findings during long-term extension of an open-label study

Table 2 Efficacy endpoints through month 12/week 52

Efficacy endpoint	mITT population
Maintained SU < 6 mg/dL for at least 80% of the time during
Month 3, n (%) [95% CI], N = 14	11 (78.6%) [49.2 − 95.3]
Month 6, n (%) [95% CI], N = 14	11 (78.6%) [49.2 − 95.3]
Months 3 and 6 (overall), n (%) [95% CI], N = 14	11 (78.6%) [49.2 − 95.3]
Month 9, n (%) [95% CI], N = 13	10 (76.9%) [46.2 − 95.0]
Month 12, n (%) [95% CI], N = 13	9 (69.2%) [38.6 − 90.9]
SU change from baseline, mg/dL, mean ± SD (median [min, max])^a
Week 24, mean ± SD (median [min, max]), n = 11	− 9.3 ± 2.8 (− 9.1 [− 15.8, − 4.7])
Week 36, mean ± SD (median [min, max]), n = 8^b	− 9.4 ± 3.3 (− 9.3 [− 15.8, − 4.7])
Week 52, mean ± SD (median [min, max]) n = 8^b	− 9.4 ± 3.3 (− 9.3 [− 15.8, − 4.7])

Confidence intervals (CI) based on exact Clopper-Pearson CI
mITT Modified intent to treat (all patients exposed to pegloticase), SU Serum urate
^a Includes patients remaining on treatment; values below the lower limit of detection were set to 0; baseline is the last observation prior to the first pegloticase infusion
^b Change from baseline was − 8.1 ± 4.0 mg/dL at week 36 and − 8.2 ± 4.1 mg/dL at week 52 for all 10 patients remaining in the study through week 52

ISSN: 1478-6362