FDA has issued a draft guidance to help companies evaluate evidence to justify health claims. Titled “Guidance for Industry: Evidence-Based Review System for the Scientific Evaluation of Health Claims,” this document describes the evidence-based review system that FDA intends to use to evaluate the publicly available scientific evidence for significant scientific agreement (SSA) health claims or qualified health claims on the relationship between a substance and a disease or health-related condition.

According to David Mark, PhD, president, dmark consulting LLC, Maynard, MA, the proposed language of the Draft Guidance is not that different from what is already in practice. “Intervention studies (randomized, controlled trials) are strongly preferred to observational studies. However, reviews and meta-analyses are not counted as evidence and the same goes for studies of flawed design or execution (FDA to define flawed),” he said. “For studies that are accepted as evidence, FDA will assign a quality rating.”

Dr. Mark says the Draft Guidance also reiterates that health claims are for “healthy” people, so studies in which people already have a health problem will not be accepted as evidence (e.g., when people with osteoarthritis get pain relief and improved function with glucosamine or chondroitin, that is not evidence for a health claim).

Lastly, Dr. Mark points out, “A very short list of surrogate endpoints are accepted as evidence for maintaining health, including total cholesterol, LDL cholesterol, blood pressure, bone density, blood sugar, insulin resistance and colon polyps. Currently, the list does not include measures such as triglycerides, C-reactive protein, platelet aggregability, knee joint space narrowing, any mental functions, or any strength or coordination functions. (More details on the new Draft Guidance can be found in this month’s “Research Process” column, which starts on page 32.)