Efficacy and Safety Study of Tazarotene (Tazorac) for the Treatment of Brittle Nails

Inclusion Criteria: * Patient has provided IRB-approved written informed consent prior to conducting any study-related procedures * Men and female patients 18 to 75 years of age * Have had a diagnosis of brittle nails * Have two target fingernails identified at baseline * Have evidence of at least two of the following signs and symptoms of brittle nails in each of the selected nail plates or severe signs (one or more) on each target nail: * trachyonychia (surface roughness) * lamellar onychoschizia (horizontal layering) * longitudinal cracking or splitting of the distal edge * Female patient of childbearing potential (not surgically sterile or at least 2 years postmenopausal) has a negative pregnancy test at baseline/day 1 and is not lactating * Sexually active female subject who is not surgically sterile or 2 years post menopausal must agree to use contraception/birth control measure while on study (e.g., oral contraceptives, diaphragms with spermicide, condoms with spermicide, intrauterine devices, Norplant System, Depo-Provera, tubal ligation) * Patients will agree to self-administer topical study medication, and will agree to complete all study procedures * Patient is judged to be in good health by medical history and physical examination * Must be able to adhere to the study visit schedule and other protocol requirements Exclusion Criteria: * Have a history of surgery of the affected fingernails * Are pregnant, nursing, or planning pregnancy prior to study enrollment * Have a disturbance of the shape of the affected fingernails (e.g., due to malformation of the underlying bone) that would interfere with the investigator's ability to evaluate photographs * Have onycholysis (lifting of the nail plate off the nailbed) of the affected fingernails * Have a fungal infection of the affected fingernails * Have a history of psoriasis or lichen planus involving any nail, or active contact dermatitis involving the affected fingernails * Have used any topical cosmetics or medicated products on the affected nails within 2 weeks of baseline visit * Have received oral antifungal treatment within 3 months of baseline visit * Have a known or suspected history of a genetic condition affecting the nails (e.g., Darier's disease, nail-patella syndrome, tuberculosis sclerosis) * Immune compromise due to HIV infection, organ transplantation, or treatment of malignancy * Chronic liver, heart, kidney, or ( untreated) thyroid disease * Have used any investigational drug within the previous 1 month or 5 half-lives of the investigational agent, whichever is longer, or 3 months for any biologic of unknown half-life * Are known to have had a substance abuse (drug or alcohol) problem within the previous 3 years * Unlikely to comply with the study protocol and prescribed treatment or is unsuitable for any other reason in the opinion of the investigator * Have current signs or symptoms of severe, progressive, or uncontrolled renal, hepatic, hematologic, gastrointestinal, endocrine, pulmonary, cardiac, neurologic, or cerebral disease; * Currently have any known malignancy or have a history of malignancy other than non-melanoma skin cancer * Are known to be infected with human immunodeficiency virus (HIV), hepatitis B or hepatitis C * Have signs of bacterial, fungal or viral skin lesions that may interfere with measurement of the target lesions.