Safety, Tolerability, PK, PD and Preliminary Efficacy of ONO-4685

A Randomised, Multi-centre, Double-blind, Placebo-controlled, Single Ascending Dose, Multiple Dose Study to Assess Safety, Tolerability, PK, PD & Preliminary Efficacy of IV Doses of ONO-4685 in Patients With Plaque Psoriasis

This is an early phase study to assess the safety and tolerability of ONO-4685 in patients with psoriasis. In addition, the study will assess how the drug is distributed and eliminated by the body (pharmacokinetics) and how the drug affects the body (pharmacodynamics). This will be done by measuring the amount of drug in the blood and measuring other markers in the body that might have been affected by ONO-4685. The study will also look at preliminary information on whether ONO-4685 might be effective in treating psoriasis.

The study will be split into three parts. Part A will assess a single dose of ONO-4685 in small groups of patients, each group planned to receive a higher dose than the last group. In Part B and C, patients will receive multiple doses of ONO-4685 over a period of 4 weeks.

Inclusion Criteria

• Subjects must be willing and able to participate in the study
• A diagnosis of plaque-type psoriasis for ≥6 months.
• Plaque-type psoriasis involving ≥3% of body surface area (BSA) (Parts B and C).
• Willing to provide skin biopsies (Parts B and C).
• Subjects in good health, as judged by medical history, medical examination, vital signs, ECG and clinical laboratory tests.
• Subjects willing to comply with the contraception and sperm and ova donation requirements of the protocol.

Exclusion Criteria

• Subjects with any clinically significant abnormality in screening tests.
• Guttate, erythrodermic or pustular psoriasis as sole or predominant form of the psoriasis, or other skin condition (eg eczema).
• Presence or history of alcohol or drugs abuse.
• Heavy smokers (more than 20 cigarettes or use more than ½ ounce (12.5 grams) of tobacco each day).
• Subjects have had any 'live' vaccines (excluding COVID-19 vaccine) during the 3 months before the first dose of study medicine.
• Subjects have had a first COVID-19 vaccine within 6 weeks or second and booster COVID-19 vaccinations within 2 weeks before the first dose of study medicine.
• Subjects have had any clinically significant disease or infection, including tuberculosis.
• Presence or history of malignancy (cancer) including lymphoproliferative disorders.
• Subject is pregnant, lactating, or breastfeeding.
• Subjects have received treatment with biologics in the last 3 months, immunosuppressant medicine or prescription medicine for psoriasis within 4 weeks before admission to the ward; have used phototherapy from 2 weeks before admission to the ward; have used highly potent or potent topical steroids within 2 weeks before admission to the ward.
• Subjects have used topical corticosteroids or Vitamin D analogues within 7 days before admission to the ward (Parts B and C).