There are numerous research opportunities in psoriasis and in psoriatic arthritis, with unmet needs in both areas. Mild to moderate psoriasis is the most common form, and there is a great need for topical therapies that can be used long-term. High-potency topical glucocorticoids are effective but should not be used chronically because they can cause skin atrophy and striae. A topical formulation of the phosphodiesterase-4 inhibitor roflumilast is being investigated for the treatment of plaque psoriasis; however, long-term safety and efficacy must be established. We currently have highly effective injectable biologic therapies for moderate to severe plaque psoriasis. We also have some oral therapies such as apremilast, which has moderate efficacy in chronic plaque psoriasis. Thus, the development of oral therapies that have efficacy and safety profiles that are similar to those of the biologic agents would be a major advancement.

There are also many important unanswered questions with respect to the development of psoriatic arthritis, which occurs at some point in approximately 30% of those with psoriasis. We are not yet able to predict which patients with psoriasis will develop psoriatic arthritis and which patients with psoriatic arthritis will progress. Further, patients with psoriasis are also at an increased risk for metabolic syndrome and atherosclerotic disease, but we currently lack a regulatory pathway to approve systemic therapies for both psoriasis and cardiovascular risk reduction. That is a major need that I anticipate might be addressed in the future. The same need exists in the treatment of other chronic immunoinflammatory diseases that are associated with increased cardiovascular risk, such as rheumatoid arthritis.

Finally, there are significant needs related to the access to and affordability of the newer targeted therapies. The underdiagnosis and undertreatment of psoriasis is a complex problem that has been described in detail in numerous studies over the years. A key contributing factor to undertreatment, in my view, is that many clinicians may be reluctant to use some of the most effective therapies because of issues such as the administrative burden of biologic therapy and the out-of-pocket costs to patients. In settings that lack staff dedicated to attend to such issues (eg, prior authorizations, step therapy, documenting medical necessity), all of the pressures and incentives favor the use of less effective, less expensive therapies that are preferred by payors and covered by insurance plans.