Friday, FDA announced the first Rx to OTC switch for a topical retinoid to treat acne. Patients will soon be able to obtain Differin Gel 0.1%( the generic name of which is adaplene) as an OTC product in their local pharmacy or grocery store. Is this big news? I think so. Back in October 2013, I wrote a blog post about the first inhaled nasal steroid (here), stating that I was surprised that FDA took the bold step in permitting an inhaled corticosteroid to treat allergic rhinitis. Now the Agency surprises me again by approving the first retinoid OTC product.
Why so surprised? The retinoids do have adverse events, the most important of which are related to potential birth defects, however, as FDA states in its announcement “While there have been no adequate and well-controlled studies of Differin Gel 0.1% in pregnant women, there is no specific evidence that Differin Gel 0.1%, when used topically as directed, causes birth defects in humans. Some other retinoid drugs have been shown to cause birth defects.” Thus, after review of available information and additional testing, adapalene is not significantly systemically absorbed, the FDA appears to be certain that adapalene’s OTC use should not be of concern.
FDA notes that in addition to the five clinical studies that originally supported the safe and effective use of Differin, “[T]o support approval for OTC marketing, the data accrued from 1996-2016 on post-marketing safety, data from consumer studies (a label comprehension study, a self-selection study, and an actual use trial), and data from a maximal use trial were submitted.”
“Overall, results from the consumer studies showed that consumers can understand the information on the OTC label, appropriately select whether the product is right for them, and use the product appropriately. The maximal use trial, a study of absorption of the drug through acne-affected skin when applied daily over a large surface area (face, shoulders, upper back and chest), demonstrated that absorption is limited, thus supporting safe use of Differin Gel 0.1% by people using it OTC. “
This OTC approval continues to signal that the Agency continues to perhaps view RX-to-OTC switch products a bit differently than it did years ago.