Interim Monitoring of Non-inferiority Trials
Year of Publication
Oden, N; Van Veldhuisen, P
Society for Clinical Trials (SCT) 37th Annual Meeting
Montreal, Quebec, Canada
HIV; Interim monitoring; Lan DeMets; Non-inferiority; ophthalmic; opioid dependent; viral suppression
We show that a non-inferiority trial can be viewed as a somewhat modified superiority trial, for which methods for interim monitoring already exist. We apply this idea to the interim monitoring of existing normal based and binary-based randomized non-inferiority trials. The normal-based ophthalmic trial compares two treatments for macular edema secondary to central retinal vein occlusion. The binary-based trial tests non-inferiority of a medication treatment compared with treatment as usual with respect to viral suppression of HIV among opioid-dependent participants in HIV clinics. We show by simulation that, in both cases, type I error is appropriately controlled via the popular Lan/DeMets alpha-spending approach under the inferiority null, and there is good power under a commonly used non-inferiority alternative hypothesis.