Closeout of Four Phase II Vanguard Trials and Patient Rollover into a Large International Phase III HIV Clinical Endpoint Trial

Abstract

Large phase III clinical trials typically require many years of planning and preparation. During this time, proposed study methods and overall trial feasibility can be assessed in smaller pilot studies. However, the patients enrolled in these pilot studies are not routinely included in the larger study. In preparation for a multinational randomized clinical end point trial of interleukin-2 in HIV-infected patients, four phase II “Vanguard” studies were initiated. These Vanguard trials served to increase safety and surrogate marker data in diverse patient cohorts, increase clinical experience with the study medication, and identify the optimal dose of medication for the phase III trial. These trials also served to assess patient recruitment potential and to develop international clinical trial coordination experience. The Vanguard trials were designed to allow continued follow-up of their patients as participants of the phase III trial once the feasibility of the phase III trial was confirmed. The purpose of this paper is to describe the steps taken in the closeout of these four phase II trials while reconsenting these patients to the phase III trial. Specifically, the reconsent process, the data collection transition plan, and the steps taken to minimize bias due to differential reconsent according to the assigned treatment arm in the phase II trial are described. The procedures employed are relevant to the reconsent of patients for long-term follow-up at the completion of clinical trials. Control Clin Trials 2001;22:42–48