In 2003, alefacept became the first Food and Drug Administration (FDA)-approved biologic for psoriasis.1 Dozens of immune-targeting therapies have since been approved for myriad dermatologic conditions from psoriasis, atopic dermatitis and hidradenitis suppurativa to cutaneous malignancy, with novel agents continuously in development. The advent of these immunomodulators, such as monoclonal antibodies and small molecule inhibitors, introduces the corresponding need for improved patient education. The burden on the dermatologist to distill the complexities of the immune system, and mechanisms of drugs which target it, is steadily increasing as more patients transition from traditional immunosuppressive medications to newer immunomodulator therapies. Many have been treated with traditional immunosuppressives such as cyclosporine, mycophenolate mofetil, or methotrexate for years, and are naturally curious about the mechanisms of their new treatments.
In the 2016 “Voice of the Patient” forum hosted by the FDA, psoriasis patients expressed concerns about potential side effects and “compromising the immune system” as significant deterrents to initiating biologics.2 Studies of non-dermatologic diseases have demonstrated similar patient concerns regarding side effects and immunocompromise,3,4 suggesting that enhanced patient education on immunomodulators’ mechanism of action may improve willingness to use and compliance with biologics over traditional immunosuppressives.
Psoriasis serves as the archetype for immunomodulatory therapy, but given the increasing number of dermatoses treated via these agents, a broad and understandable approach to explaining the mechanism of action of targeted therapies may be valuable to augment patient understanding, reduce fears associated with treatment regimens, improve willingness to transition to or begin immunomodulators, and bolster medication adherence. We propose the following educational aid to help clinicians explain the immune system and mechanisms of immune targeting therapies in a succinct, relatable fashion (Figure 1).
When counseling patients, the complex immune system can be simplified and compared to an upside-down tree. The trunk represents the immune system as a whole. Large branches arising from the trunk are analogous to upstream immune pathway targets, ie, various cell types and physical barriers. Each large branch further divides into smaller branches, which represent more specific downstream immunological pathways. Finally, the leaves represent effectors of the immune system which characterize both immunocompetence and immune-mediated disease.