Current Guidelines for Psoriasis Treatment: A Work in Progress

Treatment in Special Populations

Psoriasis patients often present with comorbidities or a complicated medical history, which can make it challenging to decide which therapy is most suitable. Patients with comorbid diseases (eg, PsA, risk of major cardiac event, IBD) or a history of NMSC and those who are pregnant or are lactating require special considerations to ensure treatment safety and efficacy.

Tumor necrosis factor α (TNF-α) and IL-17 inhibitors are used in the treatment of joint disorders and should be considered in patients with PsA. IL-23/IL-12 inhibition appears to have less benefit in patients with PsA, but studies on IL-23 inhibition (p19 antibodies) alone are ongoing.¹⁶ It has been reported that TNF-α inhibition may be beneficial in patients at risk for major cardiac events.^8,17 In patients with IBD, IL-17 inhibitors should be avoided because they may exacerbate the condition; however, TNF-α and IL-23/IL-12 inhibition have shown to be safe in patients with IBD and many agents in these classes are approved by the US Food and Drug Administration for use in this population.^18,19

Although biologics may increase the risk of developing NMSC²⁰ and should generally be avoided in patients with any active malignancy, specific guidelines for screening and initiation of treatment in patients with a history of cancer are not clearly outlined. Prior to initiating systemic therapy in any patient, a careful medical history should be obtained. These agents often are not prescribed in patients with a history of cancer until remission has been established for at least 5 years, with the exception of patients with a history of treated NMSC.⁸ Annual skin monitoring for NMSC should be undertaken for psoriasis patients on most immunomodulating systemic therapies.

Recommendations for biologic treatment in psoriasis patients who are pregnant or lactating also are limited. European guidelines have noted pregnancy as an absolute contraindication to treatment with biologics,⁷but the regulatory guidance has recently changed for some agents, so this recommendation also may evolve.²¹ British⁸ and US⁵ guidelines do not consider pregnancy a contraindication for treatment with biologics.

Information on the safety of TNF-α antagonists during pregnancy comes primarily from use in patients with IBD and rheumatologic disease. To date, reports on the incidence of congenital malformations have been generally reassuring. Because IgG antibodies are actively transferred across the placenta in the late-second or the third trimesters, neonates born to mothers on biologic treatments may have high levels of some biologic drugs at birth. As a result, live vaccination should be avoided in neonates whose mothers were treated with IgG-based biologics.

Changing Treatment Agents

Patients may need to stop and change treatment agents due to ineffectiveness, personal preference, or worsening disease. When transitioning from any systemic or biologic agent to another (other than MTX), the British Association of Dermatologists recommends a washout period of at least 1 month before initiating a new therapy.⁸ Most guidelines do not define parameters for therapy escalation when patients fail multiple systemic agents, so physicians should use clinical judgment along with consideration of patient preference and comorbidity profile to ascertain which agent is most appropriate.

Conclusion

Keeping psoriasis treatment guidelines updated can be difficult, especially as new therapeutic options for psoriasis and treatment regimens rapidly evolve. Regulatory recommendations also vary worldwide, but most guidelines are reasonably consistent without being overly prescriptive, appropriately allowing for flexibility for application in clinical practice. Nonetheless, physicians should keep in mind new or changing guidelines while tailoring psoriasis treatment recommendations to best suit their individual patients.