Phase I Study of INNA 1605 Ointment in Healthy Adults

INTERVENTION: MAD group (multiple‐dose dose escalation study) B1 group:Randomly apply 160mg of INNA1605 ointment or placebo to the skin of the subjects in a ratio of 6:2.;Group A1 of SAD (Single Dose Escalation Study):Randomly apply 60mg of INNA1605 ointment or placebo to the skin of the subjects in a ratio of 6:2.;MAD group (multiple‐dose dose escalation study) B2 group:Randomly apply 320mg of INNA1605 ointment or placebo to the skin of the subjects in a ratio of 6:2.;SAD Group (Single dose escalation study) Group A2:Randomly apply 180mg of INNA1605 ointment or placebo to the skin of the subjects in a ratio of 6:2.;SAD Group (Single dose escalation study) Group A3:Randomly apply 270mg of INNA1605 ointment or placebo to the skin of the subjects in a ratio of 6:2.;SAD Group (Single dose escalation study) Group A4:Randomly apply 270mg of INNA1605 ointment or placebo to the skin of the subjects in a ratio of 6:2.; CONDITION: Psoriasis PRIMARY OUTCOME: Safety and tolerability outcomes;Local skin tolerability outcomes; SECONDARY OUTCOME: Pharmacokinetic outcomes in the MAD study;Pharmacokinetic outcomes in the SAD study; INCLUSION CRITERIA: 1. Participants must sign the informed consent form, fully understand the study content, procedures and possible adverse reactions, and record the date of signature. 2. Healthy Chinese male or female participants aged 18 to 55 years inclusive. 3. Male participants must have a body weight of at least 50 kg, and female participants must have a body weight of at least 45 kg. Body mass inde Xmust be within 19.0 to 26.0 kg/m^2 inclusive. 4. Participants must be generally healthy, as assessed by the investigator based on medical history, surgical history, complete physical examination, vital signs, 12‐lead ECG and laboratory test results, with no evidence suggesting active or chronic disease. 5. Participants and their partners must have no pregnancy plan, including sperm donation or egg donation, from 2 weeks before screening to 3 months after the last dose, and must voluntarily use effective contraceptive measures. Non‐pharmacological contraception must b