Abstract
Purpose :
The Sirolimus Study Assessing Double-masKed Uveitis TReAtment (SAKURA) Program, which consisted of two Phase III multinational randomized clinical trials, compared the effects of intravitreal (IVT) sirolimus 440 µg vs 44 µg (low dose) in subjects with non-infectious uveitis of the posterior segment (NIU-PS). A post-hoc comparison of study eyes (SEs) and untreated fellow eyes (FEs) was performed to evaluate the impact of the absence of a placebo control in the SAKURA Program on the estimation of the effect size of IVT sirolimus on best-corrected visual acuity (BCVA).
Methods :
Subjects with active NIU-PS (vitreous haze ≥1.5+) in the study eye who were randomized to every-other-month IVT sirolimus 44 or 440 μg (n=208 in each group) and 96 untreated FEs with VH≥1.5+ from all treatment groups were included in this analysis. Post-hoc comparisons of ≥1-, ≥2-, and ≥3-line improvements in BCVA at Month 5 were performed in SEs and untreated FEs with active disease and baseline BCVA ≤70 letters (≤20/40).
Results :
A total of 253 SEs (n=127, 44 μg; n=126, 440 μg) and 52 FEs met the criteria for this post hoc analysis. The proportion of SEs with ≥1-line improvement in BCVA at Month 5 (44 μg, 44.9%; 440 μg, 48.4%) was significantly greater than that in the FE group (21.2%; p=0.003 vs 44 μg, p<0.001 vs 440 μg). The proportion of SEs with ≥2-line improvement (44 μg, 35.4%; 440 μg, 31.0%) was also significantly greater than that in the FE group (13.5%; p=0.003 vs 44 μg, p=0.015 vs 440 μg). The proportion of SEs in the 44 μg group with ≥3-line improvement was significantly greater than that in the FE group (24.4% vs 7.7%, p=0.011), however, the difference between the 440 μg and FE groups was not statistically significant (17.5% vs 7.7%, p=0.093). The mean change in BCVA from baseline in treated eyes was greater than that in the FE group at all analysis time points up to Month 5.
Conclusions :
Post hoc analysis of BCVA response rates in the SAKURA Program suggests that 44 μg IVT sirolimus has some therapeutic activity, suggesting the effect size of the 440 μg dose would have been greater if a placebo group were used as a control.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.