New data from three studies presented here today at the prestigious World Congress of Dermatology show that Propecia Pill(TM) (finasteride 1 mg), Merck & Co. Inc.’s investigational oral treatment for men with male pattern hair loss, prevented further hair loss in treated men and increased hair growth in both frontal and vertex areas of the scalp in many men. These new results broaden knowledge about the potential role for Propecia Pill in men with mild-to-moderate male pattern hair loss (androgenetic alopecia). Data from two Phase III clinical trials of 1,553 men with predominant thinning in the vertex (top of the head), presented earlier this year at the American Academy of Dermatology, demonstrated significant improvement in hair in men taking Propecia Pill compared to those receiving a placebo.

In those studies, 86 percent of men maintained or showed an increase in the amount of their hair based on hair counts during the course of the studies, compared with 42 percent of men receiving placebo.

The application for Propecia Pill is under review by the U.S. Food and Drug Administration. Upon clearance, Propecia Pill would be the first oral treatment taken once-a-day for the prevention of further hair loss and for regrowth in the most common sites of hair thinning in men. Upon marketing, it will be indicated for use in men only.

In the first presentation of the Phase III frontal hair loss study results, data show Propecia Pill significantly increased frontal scalp hair counts from baseline for patients taking Propecia Pill compared to those taking placebo. Cosmetic improvement was assessed by patients, investigators and an expert panel of dermatologists who viewed patient photographs.

Results of this 12-month study of 326 men aged 20 to 41 with mild-to-moderate frontal hair thinning show:

– In the patient assessment, 53 percent of men with frontal hair loss reported that treatment with Propecia Pill led to an improvement in the appearance of their hair, versus 30 percent of men taking placebo. Significant improvements were seen in men as early as Month 3 and were generally maintained or improved throughout the one-year study.

– Clinical investigators rated 52 percent of patients treated with Propecia Pill as showing increased hair growth versus 31 percent of men treated with placebo.

– An expert panel of dermatologists evaluating patient photographs rated 37 percent of patients treated with Propecia Pill as having increased hair growth. By comparison, only 7 percent of patients on placebo were reported to show improvement.

Using another measurement technique in this trial, investigators reported a significant improvement for men treated with Propecia Pill compared to those taking placebo in the hair density and pattern in three sections of the scalp — frontal, mid-area and vertex.

In this multicenter, randomized, double-blind, placebo-controlled study, hair counts were measured in a representative 1 cm2 area of thinning hair in the frontal scalp.

“The frontal study is unique because hair loss studies in men typically evaluate hair growth at the vertex,” said Keith Kaufman, M.D., senior director, clinical research, Merck Research Laboratories, Rahway, NJ. “Frontal thinning is commonly seen in men and it is what they may first notice when they look in the mirror.”

The frontal study results presented today are the third component of the Phase III clinical trial program for Propecia Pill, which has involved a total of 1,879 men in the United States and worldwide.

Results of the studies with Propecia Pill in preventing further hair loss also were described. A comprehensive analysis of the two Phase III trials on vertex hair loss confirmed that Propecia Pill prevented further hair loss in treated men. Hair loss in the placebo group was confirmed in each study demonstrating the progressive natural history of the hair loss process.

Based on hair counts in the two 12-month studies of men with vertex hair loss, only 14 percent of men in the group taking Propecia Pill lost hair, based on any decrease in hair count from baseline, while 58 percent of men in the placebo group continued to lose hair. In the patient questionnaire, 68 percent of men taking Propecia Pill reported that their hair loss had slowed compared to 45 percent of those taking placebo. At Month 3, figures from the patient questionnaire were 54 and 44 percent respectively.

In the frontal study, men treated with Propecia Pill also reported that their hair loss was slowing by Month 3 with 65 percent citing it by Month 12. After a year, only 45 percent of men treated with placebo reported any decrease in their hair loss.

Scientists believe that male pattern hair loss is genetically linked and triggered by the presence of dihydrotestosterone or DHT. “The ability to increase hair growth and prevent further hair loss, by specifically lowering DHT with finasteride 1 mg, provides a potential new oral therapeutic option with an excellent risk-benefit ratio for the treatment of men with male pattern hair loss,” Dr. Kaufman said.

Drug Very Well-Tolerated in Men

The tolerability of Propecia Pill was reinforced by the new data. The drug was very well tolerated, with most patients reporting no significant side effects. In the Phase III studies of 1,879 men, the overall safety profile for Propecia Pill and placebo was similar.

Side effects were infrequent and occurred in a small number of men. The only ones occurring in more than one percent of patients were decreased libido (1.8 percent of patients treated with Propecia Pill versus 1.3 percent on placebo) and erectile dysfunction (1.3 percent Propecia Pill versus 0.7 percent placebo). Decreased volume of ejaculate was reported by 0.8 percent of men treated with Propecia Pill versus 0.4 percent of those taking placebo.

“For the overwhelming majority of men — 96 percent — who took finasteride, ranging in age in our studies from 18 to 41, these side effects were not reported,” Dr. Kaufman noted. “These side effects were reversible in men who discontinued therapy and even resolved in many of these patients who preferred to continue treatment.”

Contraindicated in Pregnant Women

Propecia Pill is for use by men only. Women who are or may be pregnant must not use Propecia Pill, since it may cause a specific birth defect in a male fetus (hypospadias).

Getting to the Root of the Problem

Propecia Pill works by treating an underlying cause of male pattern hair loss by inhibiting the production of DHT, which is believed to be a major cause of hair loss. The enzyme Type II 5-alpha-reductase is involved in the production of DHT. Propecia Pill inhibits the action of Type II 5-alpha-reductase, thereby decreasing DHT concentrations in treated men by approximately 60 percent.

“This approach represents an important advance in our understanding of the science of hair loss,” Dr. Kaufman commented. “Male pattern hair loss is characterized by progressive miniaturization of hair follicles and finasteride inhibits a key factor responsible for this miniaturization. This leads to a reversal of the process of scalp hair loss in many men.”

Merck submitted new drug applications beginning in December 1996 for clearance to market Propecia Pill worldwide. “If cleared for marketing, we believe Propecia Pill will be an important product as the first oral medication for the treatment of men with male pattern hair loss,” Dr. Kaufman added.