A Study to Evaluate Safety and Efficacy of Toreforant (JNJ-38518168) in Participants With Moderate to Severe Plaque-type Psoriasis

Inclusion Criteria:

Participant must have a diagnosis of plaque-type psoriasis (with or without psoriatic arthritis [PsA]) for at least 6 months before the first administration of study drug
Participant must have a Psoriasis Area and Severity Index (PASI) Greater Than or equal to (>=) 12 at screening and at baseline
Participant must have an Investigator's Global Assessment (IGA) >=3 at screening and at baseline
A woman of childbearing potential must have a negative urine pregnancy test at screening and at Week 0
A man who is sexually active with a woman of childbearing potential and has not had a vasectomy must agree to use a barrier method of birth control during the study and for 4 months after receiving the last administration of study drug. All men must also agree to not donate sperm during the study and for 4 months after receiving the last administration of study drug

Exclusion Criteria:

Participant has a history or current signs or symptoms of severe, progressive, or uncontrolled renal, hepatic, hematologic, gastrointestinal, endocrine, pulmonary, cardiac, neurologic, cerebral, or psychiatric disease
Participant has a current malignancy or history of malignancy within 5 years before screening (with the exception of a nonmelanoma skin cancer that has been adequately treated with no evidence of recurrence for at least 3 months before the first study drug administration, or cervical carcinoma in situ that has been treated with no evidence of recurrence for at least 1 year before the first study drug administration)
Participant has a history of lymphoproliferative disease, including lymphoma; a history of monoclonal gammopathy of undetermined significance (MGUS); or signs and symptoms suggestive of possible lymphoproliferative disease, such as lymphadenopathy or splenomegaly
Participant has a history of chronic or recurrent infectious disease, including but not limited to chronic renal infection, chronic chest infection (eg, bronchiectasis), recurrent urinary tract infection (recurrent pyelonephritis or chronic nonremitting cystitis), fungal infection (mucocutaneous candidiasis), or open, draining, or infected skin wounds or ulcers
Participant has a history of an infected joint prosthesis, or has received antibiotics for a suspected infection of a joint prosthesis, if that prosthesis has not been removed or replaced
Participant has ever received any previous biologic therapy for psoriasis or psoriatic arthritis