Inclusion Criteria:
Subjects must meet all of the following criteria to be included in the study:
1. Must be able to comprehend and willing to sign an informed consent form (ICF).
2. Must complete a signed Health Information Portability and Accountability Act (HIPAA) authorization form which permits the use and disclosure of the subject's individually identifiable health information.
3. Must be at least 18 years of age.
4. Must have a minimum of 5 eligible facial, truncal, intertriginous, or extremity SKTLs. A maximum of 10 SKTLs will be targeted for treatment. An eligible SKTL must :
1. Have one or more of the following clinical features throughout the entirety of the lesion consistent with SKs: stuck-on, sharply demarcated, warty, waxy, scaly, milia-like cyst, tan to black
2. For subjects randomized for eligibility assessment with dermoscopy, SKs must also have one or more of the following dermoscopy features throughout the entirety of the lesion: crypts (comedo-like openings), milia cysts, hairpin vessels with white halo, sharp demarcation, blue-white pigmentation/veil as long as milia and crypts are present within, more than one color, cerebriform structure (network-like pattern/gyri and sulci/ridges and fissures/fat fingers), irregular vessels (inframammary only), granularity at periphery, stalactite/Tsingy pattern, plate-like/fractured pattern (Simionescu et al., 2012)
3. Have a Physician's Lesion Assessment (PLA) of 2 (a thickness that is ≤1mm)
4. Have a greatest diameter that is \>5mm but ≤15mm
5. Be a discrete, well-defined, separate lesion
6. Not be covered with hair which, in the Investigator's opinion, would interfere with the study gel treatment or the study evaluations
7. Not be pedunculated
8. Not be on the eyelid
9. Not be within 5mm of the orbital rim
5. Must be free of any known disease state or physical condition which, in the Investigator's opinion, might impair evaluation of any SKTL or which exposes the subject to an unacceptable risk by study participation.
6. Must be willing and able to follow all study instructions and to attend all study visits.
7. Must be willing to have all partial, incompletely, or non-responding SKTLs removed surgically by shave excision during the final visit.
Exclusion Criteria:
Subjects meeting any of the following criterion will be ineligible and excluded from this study:
1. Positive urine pregnancy test, pregnant, lactating, or female of childbearing potential who does not agree to use an active method of birth control (such as oral contraceptive pills (OCPs), Intrauterine devices (IUDs), birth control implants, vaginal rings, or injections) for the duration of the study.
2. SK lesions that are clinically atypical and/or rapidly growing in size or number.
3. SK lesions that have any of the following features indicative of malignancy under dermoscopy: pinpoint vessels, smooth blue-white pigmentation/veil without milia or crypts within, hairpin vessels without white halo, white artifacts, irregular vessels (except for inframammary lesions). Additionally, for lesions randomized to dermoscopy, SK lesions must not have a moth-eaten border or fingerprint structures indicative of lentigos or a network pattern indicative of a melanocytic lesion.
4. Presence of multiple eruptive SK lesions (sign of Leser-Trelat).
5. Current systemic malignancy.
6. Any use of the following systemic therapies within the specified period, or unwilling to meet the following washouts, prior to the Baseline visit and while on study:
1. Retinoids; 180 days
2. Chemotherapy; 180 days
3. Immunosuppressive therapy; 28 days
4. Biologics (e.g., interferon, interferon inducers, or immunomodulators); 28 days
5. Glucocorticosteroids; 28 days
6. Anti-metabolites (e.g., methotrexate); 28 days
7. Vismodegib; 180 days
8. Known photosensitizing medications or CYP3A inducers/inhibitors; 28 days
7. Any use of the following topical therapies within the specified period, or unwilling to meet the following washouts, prior to the Baseline visit and while on study, on or in a proximity to any SKTL that, in the Investigator's opinion, could interfere with the investigational product study treatment applications or the study assessments:
1. Laser, light or other energy-based therapy \[e.g., intense pulsed light (IPL), photo-dynamic therapy (PDT)\]; 180 days
2. Liquid nitrogen, electrodesiccation, curettage, imiquimod, 5-fluorouracil, or ingenol mebutate; 60 days
3. Retinoids; 28 days
4. Microdermabrasion or superficial chemical peels; 14 days
5. Glucocorticosteroids or antibiotics; 14 days
8. Occurrence or presence of any of the following within the specified period prior to the Baseline visit on or in the proximity of any SKTL that, in the Investigator's opinion, could interfere with the investigational product study treatment applications or the study assessments:
1. Cutaneous malignancy; 180 days
2. Sunburn; currently
3. A pre-malignancy (e.g., actinic keratosis); currently
4. Body art (e.g., tattoos, piercing, etc.); currently
9. History of sensitivity to any of the ingredients in the investigational product.
10. Any current skin disease (e.g., psoriasis, atopic dermatitis, eczema, sun damage, etc.), or other condition(s) (e.g., sunburn, excessive hair, open wounds, lupus, photosensitive disorders etc.) that, in the opinion of the Investigator, might put the subject at undue risk by study participation or interfere with the study conduct or evaluations.
11. Participation in an investigational drug trial in which administration of an investigational study medication occurred within 30 days prior to the Screening visit.
12. History of hypertrophic scarring or keloid formation.
