Development and Implementation of a Double-Blind Corticosteroid-Tapering Regimen for a Clinical Trial

Abstract EN

We describe the design and operationalization of a blinded corticosteroid-tapering regimen for a randomized trial of tocilizumab in giant cell arteritis (GCA).

To our knowledge, no clinical trial in any disease has ever employed a blinded corticosteroid-tapering regimen, but this was necessary to the design of our trial which is likely to be relevant to other investigations of steroid-sparing regimens.

Two standardized corticosteroid-tapering regimens are required for this GCA trial: a 6-month regimen in 3 arms (taken with tocilizumab 162 mg subcutaneously weekly or every other week or with placebo) and a 12-month regimen with placebo (fourth arm).

Investigators select initial prednisone doses, tapered in an open-label fashion until 20 mg/day.

Doses <20 mg/day are blinded.

At least 27 blinded blister packs are required to ensure blinding and encourage compliance.

This permits all possible daily doses but requires ≤5 capsules/day.

The number of capsules taken at any point during tapering is identical across groups.

Our approach may be extrapolated to trials beyond GCA.