When studying a new drug, it can sometimes take many years to learn whether the drug actually provides a real effect on how a patient survives, feels, or functions. A positive therapeutic effect that is clinically meaningful in the context of a given disease is known as “clinical benefit.” Mindful of the fact that it may take an extended period to measure a drug’s intended clinical benefit, in 1992 FDA instituted the Accelerated Approval regulations, allowing drugs for serious conditions that filled an unmet medical need to be approved based on a surrogate endpoint. Using a surrogate endpoint enabled the FDA to approve these drugs faster. Accelerated approval has been used primarily in settings in which the disease course is long, and an extended period would be required to measure the intended clinical benefit of a drug. [1]
The FDA may grant accelerated approval to drugs which include regenerative medicine therapies, “for a serious or life-threatening disease or condition…upon a determination that the product has an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit, or on a clinical endpoint that can be measured earlier than irreversible morbidity or mortality, that is reasonably likely to predict an effect on irreversible morbidity or mortality or other clinical benefit, taking into account the severity, rarity, or prevalence of the condition and the availability or lack of alternative treatments.”
Sponsors of drugs that have been granted accelerated approval have been required to conduct post-approval confirmatory studies to verify and describe the anticipated effects of their products on irreversible morbidity and mortality or other clinical benefit.