Image
By: George Tidmarsh, M.D., Ph.D., Director, Center for Drug Evaluation and Research
Like all drugs, sunscreens must meet rigorous standards for safety and efficacy. Because consumers rely on sunscreens as an essential part of cancer prevention and many people use them daily throughout their lives, it is critical to understand not only their protective benefits but also any potential risks from long-term use.
In September 2021, the U.S. Food and Drug Administration issued a proposed order to improve over-the-counter (OTC) sunscreen product quality, safety, and efficacy by revising the OTC sunscreen monograph. An OTC drug monograph establishes conditions, such as active ingredients, uses (indications), doses, routes of administration, labeling, and testing, under which an OTC drug in a given therapeutic category is generally recognized as safe and effective (GRASE) for its intended use. Individual products that meet the requirements of an applicable OTC monograph, among other requirements, can be marketed without product-specific premarket approval. Issued under the CARES Act, which modernized the agency’s approach to regulating OTC drugs, the 2021 proposed sunscreen order has not yet been finalized. Until it is, the proposed changes remain under review.
Under the proposed order, sunscreens containing zinc oxide and titanium dioxide would be classified as GRASE. For sunscreens containing several other widely used active ingredients—including oxybenzone, avobenzone, homosalate, octinoxate, octisalate, octocrylene, and ensulizole—the proposed order stated that additional data are required before the FDA can make a final GRASE determination.
As part of its broader mission to advance innovation in drug development, the FDA is committed to reducing reliance on animal testing. This commitment includes active collaboration with U.S. federal partners such as the National Toxicology Program’s Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM) and the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM), along with engagement from nongovernmental organizations and industry.
The FDA has taken a number of steps to reduce and minimize animal testing for sunscreens. For example, the FDA does not require animal testing of individual sunscreen products marketed under the sunscreen monograph; instead, all individual sunscreen products marketed under the monograph can be formulated in reliance on testing on active ingredients conducted to support a positive GRASE determination and establishment of monograph conditions. To make GRASE determinations for sunscreen, given the long marketing history of most sunscreen active ingredients, the FDA does not request testing in large animal species such as dogs or non-human primates. For sunscreen active ingredients, the FDA minimizes testing in rodents by not requesting 1, 3, or 6-month toxicity studies. Further, for sunscreen active ingredients that are minimally absorbed through the skin into the body and have limited safety signals, the FDA does not request fertility studies or cancer studies in a second species.
As the FDA continues to evaluate the most effective strategies to ensure sunscreen safety, the FDA strongly encourages companies to continue to develop new, reliable ways to minimize animal testing and to provide the data necessary for the FDA to make a GRASE determination for sunscreen active ingredients.
