Current US Food and Drug Administration guidelines for long term followup are unfeasible for trial sponsors and patients, especially individual investigators on five-year NIH grants and less well-financed biotechnology companies. So concluded the Biological Response Modifiers Advisory Committee (BRMAC) of the FDA's Center for Biologics Evaluation and Research during its November 16–17 meeting. Citing high costs and multiple logistical issues—such as patient compliance, investigator relocation, companies abandoning trials or dissolving—the BRMAC recommended that at five years, data collection from gene therapy trial participants fall under the umbrella of a government or non-profit organization. The committee noted that this long-term followup should be observational and conducted through a series of postcards and telephone calls. BRMAC also concurred with current FDA guidelines that require clinical trials halted when gene therapy vector is detected in a patient's semen, and that all vectors less than 40 kb—including retrovirus, adenovirus and adeno-associated virus—be sequenced prior to phase I trials. The NIH plans to hold a policy conference on follow-up requirements for gene therapy research later this year.