Those of us who prescribe isotretinoin can likely recount stories of patients for whom the therapy made a significant impact not only on their disease, but on their life. Patients with severe nodular acne—those for whom isotretinoin is indicated3—may report physical discomfort, as well as embarrassment and impaired self-esteem, as a result of the condition. Isotretinoin is also commonly prescribed for moderate acne that is treatment-resistant or poses significant risk for physical scarring or psychosocial distress. When their acne is finally brought under control, these patients tend to be highly satisfied with therapy and so grateful to their dermatology providers.
A historical limitation of treatment with isotretinoin has been the bioavailability of standard oral formulations. Isotretinoin is a lipophilic molecule. As such, absorption has been impacted by the consumption—or non-consumption—of high-fat foods at the time of medicine administration. This had led us to advise our patients to take isotretinoin with a high-fat meal. Ironically, one of the possible adverse events of isotretinoin is increased lipids, especially triglycerides, which may lead to acute pancreatitis. In an effort to enhance absorption of isotretinoin independent of diet—thus reducing the onus on the patient—Absorica, featuring Lidose technology, was developed and came to market in 2012. Lidose lipid encapsulation technology allowed isotretinoin to be partially pre-solubilized in a lipid matrix, enhancing absorption even if the drug is not taken with fatty foods.
Approved by the FDA in 2019, a new and different technological innovation has further enhanced the bioavailability of isotretinoin without depending on dietary factors. Absorica LD is a unique formulation featuring micronized technology that actually reduces the size of isotretinoin. The result of this technological innovation is that the micronized drug is absorbed more efficiently in the gut—whether taken with food or in a fasted state. Several studies, as described and discussed in the pages ahead, demonstrate that the absorption of Absorica LD is superior to Absorica. In fact, compared to the older Absorica 40mg, Absorica LD 32mg is bioequivalent when taken with food. Actually, micronized drug absorption is doubled for Absorica LD compared to Absorica when taken without food.4
The availability of Absorica LD offers practical benefits. Because micronization improves isotretinoin absorption levels, it is possible to decrease the cumulative dose of isotretinoin required for a patient taking Absorica LD, compared to generic isotretinoin. It is worth noting that the American Academy of Dermatology (AAD) currently recommends a target cumulative dose for isotretinoin in the treatment of moderate to severe nodular acne of 120–150mg/kg. A lower relapse rate was seen for those treated with a cumulative dose of 120mg/kg and the therapeutic benefit may plateau at 150mg/kg.3 From a practical perspective, since the mg dosage of micronized Absorica LD is 20% less than conventional isotretinoin and old Absorica (with Lidose technology), and achieves similar drug levels under fed conditions, the target cumulative dose could be decreased by 20% as well to 100mg/kg–120mg/kg.3
In the past, dermatology providers advised their patients to take conventional isotretinoin with a high-fat meal in order to optimize drug absorption. We know such recommendations can be challenging for patients—especially adolescents—to adhere to on a daily basis, especially when patients may not eat a consistently-timed morning meal. Not to mention, such guidance may not encourage healthy eating habits. With Absorica LD, our patients no longer need to focus on administering isotretinoin in conjunction with a high-fat meal.