A Study to Evaluate and Compare the Efficacy and Pharmacokinetics of MK-0873 for the Treatment of Plaque Psoriasis (MK-0873-022)

Inclusion Criteria

Is a male or female 18 to 65 years of age
Female subjects of reproductive potential must have a negative serum pregnancy test at screening and agree to use and/or have their partner use two (2) acceptable methods of birth control
Has a Body Mass Index (BMI) ≤36 kg/m^2 (up to 40 kg/m^2 may be enrolled, in consultation with Sponsor)
Has diagnosis of plaque-type psoriasis at least 6 month prior to administration of study drug (participants with concurrent psoriatic arthritis may be enrolled)

Has plaque-type psoriasis with at least two pairs of symmetrically located plaque lesions that exhibit similar baseline TLS values (TLS in each plaque ≥6 and

± 2 points difference between left and right plaque lesions)

Has plaque-type psoriasis with lesion severity score ≥4 covering at least 1 to 20% of total body surface area at screening and at baseline.
Is judged to be in good health based on medical history, physical examination, vital sign measurements, electrocardiogram assessment, and laboratory safety tests

Exclusion Criteria

Has nonplaque forms of psoriasis (e.g., Erythrodermic, guttate, or pustular).
Has current drug-induced psoriasis (e.g., a new onset of psoriasis or an exacerbation of psoriasis from beta blockers, calcium channel blockers or lithium).
Has received phototherapy or any systemic medications/treatments that could affect psoriasis or TLS evaluation (including but not limited to oral or injectable corticosteroids, retinoids, 1, 25-dihydroxy vitamin D3 and analogues, psoralens, sulfsalazine, hydroxyurea, fumaric acid derivatives, or herbal treatments) within 4 weeks of study drug administration.
Has used topical medications/treatments that could affect psoriasis or TLS evaluation (e.g., corticosteroids, coal tar, anthralin, calcipotriene, topical vitamin D derivatives, retinoids, tazarotene, methoxsalen, trimethyl psoralens) within 2 weeks of study drug administration.
Has used any systemic immunosuppressants (e.g., Methotrexate, azathioprine, cyclosporine, 6-thioguanine, mercaptopurine, mycophenolate mofetil, hydroxyurea, or tacrolimus) within 4 weeks of study drug administration or biologics (e.g., anti-tumor necrosis factor [TNF], anti-interleukins) within 3 months of study drug administration.