Preliminary data release for randomized clinical trials of noninferiority: A new proposal

Noninferiority trials often require a long follow-up period for the data to reach the maturity needed for definitive analysis. A proposal is presented that allows for early release of outcome data from a carefully specified subset of noninferiority trials. This subset is defined so that the early release of the data will be potentially useful to patients who face a treatment decision but will not compromise the integrity of the trial or interfere with the completion of the trial to its definitive analysis. In particular, the release of the data will only occur after the last participant has been randomly assigned and is off treatment-arm-specific therapy and only if it is unlikely that subsequent treatment and/or follow-up practices will change based on the knowledge of released data. In contrast to standard interim monitoring, (1) the release of the data would be automatic and independent of the observed data, and (2) the trial would continue on to its planned final analysis and not be stopped. Examples are given demonstrating how the proposal would work, along with a discussion of possible objections to the proposal.