Acne vulgaris is a chronic inflammatory skin disease of the follicular sebaceous glandular unit that occurs in adolescence, mainly involving the face, accompanied by erythema, hyperpigmentation and scarring. The pathogenesis of acne has not yet been fully elucidated, and is mainly thought to be related to four aspects: overproduction of lipids by sebaceous glands, abnormal keratinization of follicular sebaceous gland ducts, proliferation of follicular microorganisms, such as Propionibacterium acnes, inflammation, and immune response. CD Formulation provides in vitro anti-acne testing to help clients efficiently conduct efficacy testing of cosmetic products, which can in turn benefit the development of cosmetic products.