The US FDA draft guidance on the safety and effectiveness data for over-the-counter sunscreen fails to reflect the current science on ingredient safety assessment, according to industry and NGOs.
The draft guidance, "Over-the-counter sunscreens: safety and effectiveness data", was issued for public comment in November. Once finalised, it will reflect the FDA’s “current thinking” on the data needed to determine if an active ingredient for use in nonprescription sunscreen is “generally recognised as safe and effective (Grase)”.
The Public Access to SunScreens (PASS) coalition – a stakeholder group that includes health NGOs, chemical and sunscreen manufacturers, and dermatologists – says that the approach outlined in the guidance “falls short”.
Specific issues raised include that:
- the FDA relies on the maximal usage trial (MUsT) as part of its assessment, despite there being no “established protocol” for its use on sunscreen ingredients;
- the evidence of dermal absorption safety threshold, referenced in the guidance, “applies a new and arbitrary scientific standard regarding carcinogenicity and toxicity tests”; and
- several of the agency’s assumptions - including those regarding body surface coverage area, its required number of test subjects and the number of formulations to be tested - should all be revised.
PASS says: “By calling for manufacturers to complete new tests prior to marketing – including tests never before used on sunscreen ingredients, tests required by no other countries and for which there is no agreed-upon protocol – the FDA’s proposal may simply continue to deny Americans access to the latest skin cancer prevention products available throughout the rest of the world.”
It adds that a risk-benefit analysis that weighs the risk of skin cancer against ingredient safety risk is “crucial”.
Gradient Corporation, a toxicology consultancy, says in comments that several test methods were absent from the guidance, including:
- adverse outcome pathway (AOP) paradigm;
- structure-activity relationships and read-across approaches; and
- high throughput in vitro and in silico screening tools.
In a joint release from the Personal Care Products Council (PCPC) and the Consumer Healthcare Products Association (CHPA), the trade groups say: “With few exceptions, FDA’s thinking is not reflective of the current state-of-the-art ingredient safety assessment framework, recognised and used by the majority of health authorities worldwide.”
They have called on the agency to convene hearings or workshops “to allow further discussion to attempt to reconcile these differences”, and for it to “[revise] its position to reflect the current science of ingredient safety assessments”.
The draft’s issuances come under the implementation of the 2014 Sunscreen Innovation Act (SIA). This was intended to streamline the FDA’s approval process for sunscreen ingredients in over-the-counter (OTC) products.
The FDA last approved a new sunscreen ingredient in the 1990s, and has a backlog of eight substance applications that date to as early as 2002.
A spokesperson for the agency said it "will take into account all comments received, as well as other relevant considerations, in finalising the draft guidance document".
The FDA intends to finalise the guidance by 26 November, as required by the SIA.
This article was amended on 4 March to include a comment from the FDA.