Guselkumab in the Treatment of Pityriasis Rubra Pilaris (PRP)

Inclusion Criteria: * Diagnosis of PRP by clinical assessment * Male age 18-99, willing to use a reliable form of birth control if sexually active with a woman who is able to become pregnant. * Female age 18-99; either of non-childbearing potential or of childbearing potential who test negative for pregnancy and agree to use a reliable method of birth control or remain abstinent during the study and for at least 12 weeks following the last dose of guselkumab. * Involved body surface area (BSA) ≥ 10% at baseline (moderate-to-severe disease). * Are a candidate for phototherapy and/or systemic therapy. Exclusion Criteria: * Willingness to travel to Oregon Health and Science University (OHSU) for all study visits, or willing/able to participate in remote videoconferencing visits with access to a computer with internet and webcam capabilities. * Known malignancy or lymphoproliferative disease (except treated basal cell skin cancer, treated squamous cell skin cancer, or treated cervical carcinoma in situ) for at least 5 years. * Active, untreated, acute or chronic infection, or immunocompromised to an extent that such that participation in the study would pose an unacceptable risk to the subject. * Positive for human immunodeficiency virus, hepatitis B virus, or hepatitis C virus. * Have latent or active untreated tuberculosis (TB), a positive QuantiFERON-TB Gold test result, signs or symptoms of active TB on medical history or physical examination, or close contact with a perso…