Eligibility Criteria:
Inclusion Criteria:
* Healthy adult males and females at least 18 years of age
* Subjects of any Fitzpatrick skin type or race provided their degree of skin pigmentation does not, in the Investigator or designee's opinion, interfere with study assessments
* Subject has no signs of irritation (i.e., a Reaction Grade of "0") at patch application sites on the back prior to the initial patch application on Day 1
* Subject must have read, understood, and signed the informed consent form prior to any study-related procedure being performed
* Subject is willing and able to comply with all scheduled study visits, urine pregnancy tests (if applicable), contraception requirements (male and female), and other study requirements
* Subject is willing to avoid extensive sun exposure, phototherapy, or use of a tanning salon for the duration of the study
Exclusion Criteria:
* Women who are pregnant or lactating
* Women of childbearing potential who are sexually active and are not willing to use a highly effective method of birth control during the study period that includes double barrier, IUD, or hormonal contraceptive combined with single barrier, or abstinence
* Women of childbearing potential who have had unprotected sexual intercourse within 30 days prior to Day 1
* Males who are sexually active and not willing to use a condom, and have a partner who is capable of becoming pregnant, if neither has had surgery to become sterilized, and/or who are not willing to use double barrier or whose partner is not using a highly effective method of birth control (e.g., IUD, or hormonal contraception combined with single barrier)
* Subject has any skin condition that, in the Investigator's opinion, could interfere with the study assessments or put the subject at undue risk by study participation
* Subject has severe atopic dermatitis/eczema, psoriasis or chronic asthma
* Subject has tattoos, excessive hair, moles, scarring, etc. which would interfere with patching
* Subject has a history of sensitivity to any component of any of the Test Materials
* Use of any of the following medications:
* Systemic or topical glucocorticoids within 4 weeks prior to Day 1
* Systemic or topical analgesics (e.g., NSAIDs, high dose aspirin, etc.) within 1 week prior to Day 1. Note: Daily use of ≤325 mg of aspirin for cardiovascular disease or prophylaxis is allowed. Maximum daily use of Tylenol ≤3000 mg is allowed.
* Antihistamines within 1 week prior to Day 1. Note: H2 blockers such as Pepcid, Zantac, and Tagamet are permitted.
* Anti-inflammatories within 1 week prior to Day 1
* Immunosuppressant medications (e.g., TNF-alpha inhibitors, topical tacrolimus, etc.) within 4 weeks prior to Day 1 (or within 6 half-lives prior to Day 1 for biologics)
* Subject has had previous treatment with SM04755
* Subject has an active infection of hepatitis B or C or human immunodeficiency virus (HIV) infection as determined by an interview
* Participation in a clinical research trial that included the receipt of an investigational product or any experimental therapeutic procedure within 8 weeks prior to Screening, or planned participation in any such trial; the last date of participation in the trial, not the last date of receipt of investigational product, must be at least 8 weeks prior to Screening