This is a two-arm, single center placebo-controlled double-blind proof of concept study which will evaluate the safety and efficacy of topical cidofovir (both 1% and 3%)compared to placebo for the prevention of hair growth.

This is a phase II randomized, placebo controlled double blind, dose-ranging clinical trial of topical cidofovir for the prevention of hair growth. This proof of concept study will evaluate 1% and 3% cidofovir in petrolatum topically applied once a day to the target treatment area on the hair bearing area of the face known as the beard area. This target area will be of a circular shape with a diameter of three centimeters along the jaw line of one side of the face.The first 14 enrolled subjects in the study will be randomized in a 1:1 fashion to receive either 1% topical cidofovir and placebo or 3% topical cidofovir and placebo. The last cohort of subjects to be enrolled in the study to achieve a total of 16 evaluable subjects will all receive the 3% formulation and placebo. Subjects will also be randomized as to which side of their face (left or right) will receive active drug versus placebo.

Subjects will be treated for up to eight weeks. Any subject who achieves 100% alopecia (which corresponds to a 0 on the PGA of Hair Density) in the treated area prior to eight weeks will be classified as a responder and will discontinue active treatment and begin the four week observation period. From the time of discontinuing treatment, subjects will be followed for four weeks during which time safety data will be collected.

Inclusion Criteria:

1. Subjects must be able to give informed consent.
2. Subjects must be male, age 18 years or older.
3. Score of 4 or 5 on the Physician's Global Assessment of Hair Density at baseline
4. Subjects must have to shave at least once a day to avoid a visible beard with a hair length that is above the skin line.
5. Male subjects who are sexually active with female partners and are capable of fertilization must ensure that their female partners will either be postmenopausal, surgically incapable of childbearing, or will use a medically acceptable method of contraception throughout the entire study period. Medically acceptable methods of contraception that may be used by the subject and/or partner include oral contraceptives or patch, diaphragms with spermicide, IUD, condom with spermicide, or progestin implant or injection. Female partners taking oral contraceptives must have taken them consistently for at least two months prior to subject receiving study medication.
6. Subjects must be able to limit the use of alcohol to 2 or fewer drinks per day for the duration of the study period. One drink corresponds to 6 oz of wine, 12 oz of beer or 1 oz of hard liquor.
7. Subjects must be willing and able to avoid exposure of the study drug to others
8. Subjects must be able to understand and comply with drug storage and application procedures

Exclusion Criteria:

1. Use of an investigational medication 180 days prior to study enrollment (day 0).
2. Use of topical medication that can affect hair growth during the 8 weeks prior to the baseline visit (e.g. minoxidil, eflornithine HCl).
3. Use of a systemic medication that can affect hair growth during the 180 days prior to the baseline visit (e.g. minoxidil, cyclosporine A, finasteride).
4. Clinically significant abnormality in liver function, renal function, chemistry panel or CBC (AST or ALT ≥ 2 times the laboratory's upper limit of normal, hemoglobin < 10.0 g/dL, platelet count <125,000/cm3, white blood count <3,500 cells/cm3 or > 15,000 cells/cm3, or serum creatinine ≥ 1.5 mg/dL) within two weeks of the baseline visit.
5. Proteinuria or hematuria upon urine analysis within two weeks of the baseline visit.
6. Active inflammatory skin disease in the treatment area (e.g. acne, cysts) or neoplasms in the treatment area that in the judgment of the investigator precludes enrollment.
7. History of skin cancer or actinic keratoses in the treatment area.
8. Concomitant use of any topical medication in the target areas during the study.
9. Previous history of alopecia areata.
10. Use of a nephrotoxic medication (tobramycin, gentamycin, amikacin, amphotericin B, foscarnet, vancomycin, non-steroidal anti-inflammatory agents) 7 days prior to the baseline visit.