Treatment Assignment and Randomization Treatment assignments will be stratified according to clinical center. The treatment assignments will be generated by the Data Coordinating Center (DCC) with the use of a pseudo-random-number generator with randomly permutated blocks that will be used to ensure balance between the number of subjects assigned to each treatment (ACTH or no ACTH). Before the study starts, the institutional research coordinator at each clinical center will be given a batch of 20 sealed, sequenced, opaque envelopes containing the treatment assignment and will have a unique identification number consisting of the clinical center stratum.