Safety, Tolerability, and Efficacy Study of LFX453 in Actinic Keratosis Patients

Key Inclusion Criteria: * Male patients, and female patients of non-childbearing potential, age ≥ 18 to ≤ 75 years (at the time of the screening visit), and in general good health as determined by past medical history, physical examination, vital signs, electrocardiogram, and laboratory tests at screening * Patients with at least five clinically typical, visible or palpable non-hyperkeratotic AK lesions within a contiguous area of 25 cm2, or within 2 areas for a maximum total of 25cm2, on the face (at least 2 cm from the periocular areas, lips, nares and ears) and/or balding scalp * Presence of at least one additional visible or palpable non hyperkeratotic AK lesion outside of the selected area amenable to the collection of a skin biopsy, and located at least at 2 cm from the limits of the area to receive treatment * Male patients had to agree to use adequate contraception for the duration of the study. Key Exclusion Criteria: * Known hypersensitivity to any constituents of the study drugs (including local anesthetics if consenting to biopsies) or known allergies to imiquimod or to drugs of similar chemical classes or history of serious allergic reaction. * Presence of atopic dermatitis, eczema, psoriasis, rosacea or other possible confounding skin conditions on face or balding scalp even outside of the treatment area. * Invasive tumors within the treatment area, e.g., merkel cell carcinoma, melanoma, squamous cell carcinoma (SCC), basal cell carcinoma, the latter being accepted if completely surgically removed. * Women of child-bearing potential, defined as all women physiologically capable of becoming pregnant. * History of hypertrophic scarring. * Concurrent disease that suppresses the immune system.