If an AIDS vaccine is shown to be safe and efficacious in Phase III clinical trials, regulatory authorities review the data submitted by trial sponsors and decide whether or not to permit its introduction into the market. In the US, for example, the Food and Drug Administration conducts such reviews. In South Africa, the Medicines Control Council handles this task. In any case, every vaccine must be approved for use by the regulatory authorities of each of the countries where it is to be introduced. Regulators examine—and subsequently monitor—everything from the processes of vaccine production, the benefits and risks associated with the vaccine, its degree of efficacy, and the label and packaging that will be used to inform the public about the product. Regulatory agencies sometimes require sponsors to perform a second Phase III trial to confirm and expand on the initial study, testing, for example, how effective the vaccine is in populations other than those enrolled in the initial efficacy study.

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