Table 2.
Flare outcomes during pivotal clinical trials of urate-lowering therapy for gout
| Trials | Flare outcomes in the early trial period | Flare outcomes in the late trial period | Flare outcomes for the entire trial period | Ref. |
|---|---|---|---|---|
| FACT (Becker et al. 2005) | Day 1 to week 8: more participants with gout flare in the febuxostat 120 mg group than in the allopurinol group (36% vs 21%; P < 0.001) |
Weeks 9–52: no difference in the proportion of participants with gout flare in the febuxostat 120 mg group compared with the allopurinol group (70% vs 64%) Weeks 49–52: no difference in the proportion of participants with gout flare in the febuxostat 120 mg group compared with the allopurinol group (6% vs 11%) |
Not reported | 24 |
| C0405 and C0406 (Sundy et al. 2011) |
Months 1–3: higher gout flare incidence in the bi-weekly pegloticase group than in the placebo group (75% vs 53%; P = 0.02) Months 1–3: more gout flares in the bi-weekly pegloticase group than in the placebo group (mean 2.3 vs 1.2; P = 0.001) |
Months 4–6: lower gout flare incidence in the bi-weekly pegloticase group than in the placebo group (41% vs 67%; P = 0.007) Months 4–6: fewer gout flares in the bi-weekly pegloticase group than in the placebo (mean 0.8 vs 1.3; P = 0.06) |
Not reported | 26 |
| CLEAR-1 (Saag et al. 2017) | Not reported | Months 7–12: no difference in the lesinurad 400 mg group and the placebo group (mean 0.51 vs 0.58; P = 0.61) | Not reported | 33 |
| Doherty et al. 2018 | Year 1: more participants in the nurse-led group than in the usual care group experienced ≥2 gout flares (54% vs 40%, risk ratio 1.36 (95% CI 1.05–1.77)) | Year 2: fewer participants in the nurse-led group than in the usual care group experienced ≥2 gout flares (8% vs 24%, risk ratio 0.33 (95% CI 0.19–0.57)) | Not reported | 25 |
| CSP594 (O’Dell et al. 2022) |
Weeks 0–48: proportion of participants experiencing one or more gout flares not reported Secondary end point: weeks 0–24: no difference in gout flare rate in the allopurinol group and the febuxostat group (2.09 vs 2.25 flares per person years; rate ratio 0.93 (95% CI 0.81–1.06)) Secondary end point: weeks 25–48: no difference in gout flare rate in the allopurinol group and the febuxostat group (1.60 vs 1.59 flares per person years; rate ratio 1.00 (95% CI 0.85–1.18)) |
Primary end point: weeks 49–72: fewer participants with gout flares in the allopurinol group than in the febuxostat group (36.5% vs 43.5%; risk ratio −7 (95% CI −∞ to −1.2); P < 0.001 for non-inferiority of allopurinol) Secondary end point: weeks 49–72: fewer gout flares in the allopurinol group than in the febuxostat group (1.48 vs 2.02 flares per person years; rate ratio 0.73 (95% CI 0.63–0.86)) |
Proportion of participants experiencing one or more gout flares over the entire study period not reported Gout flare rate over the entire study period reported in the manuscript: fewer gout flares in the allopurinol group than in the febuxostat group (1.73 vs 1.97 flares per person-years, rate ratio 0.88 (95% CI 0.81–0.96)) |
27 |
Trials in this table represent the major phase III trials for urate-lowering therapy approved by the FDA since 2009 or large investigator-initiated strategy trials (>500 participants). Where more than one dose was tested, data for the highest dose are presented.