A group sequential Holm procedure with multiple primary endpoints.

We propose a group sequential Holm procedure when there are multiple primary endpoints. This method addresses multiplicities arising from multiple primary endpoints and from multiple analyses in a group sequential design. It has been shown to be a closed testing procedure and preserves the familywise error rate in the strong sense. When multiple endpoints are the only concern without an interim analysis, the method simplifies to the weighted Holm procedure. The proposed method is more powerful than the parallel group sequential method and avoids the need to anticipate the testing order as in the fixed sequence testing scheme.