Topilutamide (fluridil)

updated

Topilutamide (fluridil) is a topical anti-androgen studied for androgenetic alopecia in two small, old studies: a 3-month placebo-controlled study in 43 men that reported a higher anagen percentage, and an open 9-month study in 11 women that found no change in anagen percentage. No drug approval was found, nothing has been registered or replicated, and both studies come from one group whose first author is listed with a company named as a licensor of fluridil rights.

Androgen receptor antagonist (topical)

  • No drug approval was found: openFDA Drugs@FDA returned no record and DailyMed returned no label for fluridil, topilutamide or Eucapil, and ClinicalTrials.gov returned no records for fluridil, topilutamide, Eucapil or NP-619, on 10 October 2026.
  • In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind placebo-controlled study of 2% fluridil, the anagen percentage did not change on placebo and rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months; the abstract gives no arm sizes, p values, hair counts or hair density.
  • In 11 women on a cyproterone acetate and ethinylestradiol pill, an open 9-month study found no change in anagen percentage (92.86% at baseline, 92.69% at 9 months) and a rise in hair stem diameter (P < 0.001 at 9 months).
  • No fluridil or its catabolites were found in serum at a 5 ng/mL method limit in the women's study, and the paper cites earlier work finding none at that limit in 40 men.
  • A PubMed search on 10 October 2026 returned 2 records for fluridil, Eucapil, BP-766 or topilutamide, and no randomized trial against minoxidil or finasteride, no registered trial, no independent replication and no study after 2006 was found.
  • The studied product, Eucapil, is a 2% solution in anhydrous isopropanol that a 2006 paper calls a cosmetic product, and fluridil is unstable in water, so a product that is not an anhydrous solution is not shown to match it.

What is topilutamide (fluridil), and has anyone approved it?

Topilutamide and fluridil are one compound, a topical anti-androgen. No drug approval was found on 10 October 2026, a 2006 paper calls the studied product, Eucapil, a cosmetic, and a 2008 company press release said it was sold outside the US.

Topilutamide and fluridil are one PubChem record: CID 9930988, C13H11F6N3O5, 403.23 g/mol, CAS 260980-89-0, with synonyms BP-766 and topilutamidum. The IUPAC name is 2-hydroxy-2-methyl-N-[4-nitro-3-(trifluoromethyl)phenyl]-3-[(2,2,2-trifluoroacetyl)amino]propanamide. The studied product, Eucapil, is a cosmetic solution of 2% fluridil in anhydrous isopropanol.

openFDA Drugs@FDA returned no record and DailyMed returned no label for fluridil, topilutamide or Eucapil, and ClinicalTrials.gov returned no records for fluridil, topilutamide, Eucapil or NP-619, all on 10 October 2026. The 2006 clinical paper calls Eucapil a cosmetic product. A 2008 company press release said North Park Aesthetics acquired worldwide rights from Biophysica, Inc. and Interpharma Praha, named fluridil the main ingredient of NP-619 as its phase 2 product for androgenetic alopecia, and said Eucapil was sold outside the US. No NP-619 trial record or result was found, and whether any fluridil product is currently marketed was not established.

PubChem: topilutamide and fluridil are one record

Chemical identity record

National Library of Medicine. PubChem compound record CID 9930988 (topilutamide, fluridil).

Topilutamide and fluridil are one PubChem record: CID 9930988, C13H11F6N3O5, 403.23 g/mol, CAS 260980-89-0, with synonyms BP-766 and topilutamidum. IUPAC name 2-hydroxy-2-methyl-N-[4-nitro-3-(trifluoromethyl)phenyl]-3-[(2,2,2-trifluoroacetyl)amino]propanamide. The studied product, Eucapil, is a cosmetic solution of 2% fluridil in anhydrous isopropanol.

Participants / model
Chemical identity, not a clinical population
Treatment
Defined molecule
Follow-up
Not applicable
Study design
NLM chemical record
Funding
not stated in the source

Identity record only; it says nothing about efficacy or safety.

Read the original source
Drugs@FDA, DailyMed and ClinicalTrials.gov, 10 October 2026: nothing; 2008 company statement: sold outside the US

Regulatory record

U.S. Food and Drug Administration, openFDA Drugs@FDA, DailyMed, U.S. National Library of Medicine, and ClinicalTrials.gov: searches run on 10 October 2026 for fluridil, topilutamide, Eucapil and NP-619. With a 2008 North Park Aesthetics press release (BioSpace copy).

openFDA Drugs@FDA returned no record and DailyMed returned no label for fluridil, topilutamide or Eucapil, and ClinicalTrials.gov returned no records for fluridil, topilutamide, Eucapil or NP-619, all on 10 October 2026. The 2006 clinical paper calls Eucapil a cosmetic product. A 2008 press release (company statement) said North Park Aesthetics acquired worldwide rights from Biophysica, Inc. and Interpharma Praha, named fluridil the main ingredient of NP-619 as its phase 2 product for androgenetic alopecia, and said Eucapil was sold outside the US. No NP-619 trial record or result was found.

Participants / model
Not a clinical population
Treatment
Drug applications, labels, registry, and a company press release
Follow-up
Searches run on 10 October 2026; press release from 2008
Study design
FDA record and registry searches, with a company press release (sponsor's own account)
Funding
not stated in the source

The absence of a US record is a US-scoped statement. Whether any fluridil product is currently marketed was not established beyond the 2006 paper and the 2008 company statement.

Read the original source
Women: 11 on Eucapil for 9 months, anagen share unchanged, stem diameter up

Human study

Scripta Medica (Brno). 2006;79(1):35-48. Open, uncontrolled 9-month study of Eucapil in women. The journal is not indexed in PubMed.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil (2% fluridil in anhydrous isopropanol, applied daily) did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change), which the authors attribute to the prior antiandrogen use. Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. Two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA. Serum testosterone and SHBG were interpreted against the women's concurrent cyproterone acetate pill use, which limits what these values can show. The paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing.

Participants / model
11 women aged 22 to 45 with androgenetic alopecia (Ludwig stage I to II) on a cyproterone acetate and ethinylestradiol pill; serum data also cited from 40 men in earlier work
Treatment
Topical Eucapil (2% fluridil in anhydrous isopropanol) once daily
Follow-up
9 months
Study design
Open-label study, no control group
Funding
not stated in the source

The authors attribute the unchanged anagen percentage to the prior antiandrogen use. The study has no control group, and the serum hormone values are limited by the women's concurrent pill use. The journal is not indexed in PubMed.

Read the original source

What did the studies in men find?

A double-blind placebo-controlled study in 43 men reported the anagen percentage unchanged on placebo and rising from 76% to 85% on 2% fluridil at 3 months. The abstract gives no arm sizes, p values, hair counts or hair density, and no replication exists.

After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation.

In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind, placebo-controlled study of 2% fluridil, the anagen percentage on phototrichogram did not change in placebo subjects but rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months. Former placebo subjects rose from 76% to 85% after 6 months on fluridil. The authors report normal sexual function, libido, hematology and blood chemistry throughout, with no stated instrument for sexual function in the abstract. The abstract gives no arm sizes, p values, hair counts or hair density.

Men: 43 with AGA on 2% fluridil, anagen share 76% to 85%; patch test in 20 men

Clinical trial

Sovak M et al. Dermatol Surg. 2002;28(8):678-85. PMID 12174057.

After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation. In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind, placebo-controlled study of 2% fluridil, the anagen percentage on phototrichogram did not change in placebo subjects but rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months; former placebo subjects rose from 76% to 85% after 6 months on fluridil. The authors report normal sexual function, libido, hematology and blood chemistry throughout, and no fluridil or its decomposition product BP-34 in serum at 0, 3 or 90 days. The abstract gives no arm sizes, p values, hair counts or hair density, and it notes that at 3 months, in the spring, serum testosterone rose within the normal range equally in placebo and fluridil groups.

Participants / model
20 men (patch test); 43 men with androgenetic alopecia, Norwood II to Va
Treatment
Topical 2% fluridil solution in isopropanol, daily; forearm patches with 2, 4 and 6% fluridil
Follow-up
21-day patch test; 3-month blinded period, with follow-up to 9 months
Study design
Double-blind placebo-controlled study; arm sizes are not stated in the abstract
Funding
not stated in the source

The blinded, placebo-controlled period was 3 months in 43 men. The endpoint was anagen percentage, a hair-cycle proxy, not hair count or density. Because former placebo subjects were later treated with fluridil, data beyond the blinded period are not placebo-controlled. The PubMed record has no conflict-of-interest statement, and the first author is listed with Biophysica, Inc. in the 2006 paper, a company that the 2008 release names as a licensor of fluridil rights. No independent replication was found.

Read the original source

How reliable is the study in men?

Thin. The blinded period was 3 months in 43 men, the endpoint was a hair-cycle proxy, arm sizes are not stated, and the first author is listed with a company named as a licensor of fluridil rights. No independent replication was found.

The blinded, placebo-controlled period was 3 months in 43 men. The endpoint was the anagen percentage, a hair-cycle proxy, not hair count or density, and the abstract does not state arm sizes. Because former placebo subjects were later treated with fluridil, the data beyond the blinded period are not placebo-controlled. The abstract also notes that at 3 months, in the spring, serum testosterone rose within the normal range equally in placebo and fluridil groups.

The PubMed record for the 2002 paper has no conflict-of-interest statement, and its first author is listed with Biophysica, Inc. in the 2006 paper. A 2008 company press release names Biophysica, Inc. as a licensor of fluridil rights. A PubMed search on 10 October 2026 found no randomized trial against minoxidil or finasteride, no registered trial, no independent replication and no study after 2006. The arm sizes, p values and hair count data would need the full paper, which was not read.

Men: 43 with AGA on 2% fluridil, anagen share 76% to 85%; patch test in 20 men

Clinical trial

Sovak M et al. Dermatol Surg. 2002;28(8):678-85. PMID 12174057.

After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation. In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind, placebo-controlled study of 2% fluridil, the anagen percentage on phototrichogram did not change in placebo subjects but rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months; former placebo subjects rose from 76% to 85% after 6 months on fluridil. The authors report normal sexual function, libido, hematology and blood chemistry throughout, and no fluridil or its decomposition product BP-34 in serum at 0, 3 or 90 days. The abstract gives no arm sizes, p values, hair counts or hair density, and it notes that at 3 months, in the spring, serum testosterone rose within the normal range equally in placebo and fluridil groups.

Participants / model
20 men (patch test); 43 men with androgenetic alopecia, Norwood II to Va
Treatment
Topical 2% fluridil solution in isopropanol, daily; forearm patches with 2, 4 and 6% fluridil
Follow-up
21-day patch test; 3-month blinded period, with follow-up to 9 months
Study design
Double-blind placebo-controlled study; arm sizes are not stated in the abstract
Funding
not stated in the source

The blinded, placebo-controlled period was 3 months in 43 men. The endpoint was anagen percentage, a hair-cycle proxy, not hair count or density. Because former placebo subjects were later treated with fluridil, data beyond the blinded period are not placebo-controlled. The PubMed record has no conflict-of-interest statement, and the first author is listed with Biophysica, Inc. in the 2006 paper, a company that the 2008 release names as a licensor of fluridil rights. No independent replication was found.

Read the original source
Women: 11 on Eucapil for 9 months, anagen share unchanged, stem diameter up

Human study

Scripta Medica (Brno). 2006;79(1):35-48. Open, uncontrolled 9-month study of Eucapil in women. The journal is not indexed in PubMed.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil (2% fluridil in anhydrous isopropanol, applied daily) did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change), which the authors attribute to the prior antiandrogen use. Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. Two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA. Serum testosterone and SHBG were interpreted against the women's concurrent cyproterone acetate pill use, which limits what these values can show. The paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing.

Participants / model
11 women aged 22 to 45 with androgenetic alopecia (Ludwig stage I to II) on a cyproterone acetate and ethinylestradiol pill; serum data also cited from 40 men in earlier work
Treatment
Topical Eucapil (2% fluridil in anhydrous isopropanol) once daily
Follow-up
9 months
Study design
Open-label study, no control group
Funding
not stated in the source

The authors attribute the unchanged anagen percentage to the prior antiandrogen use. The study has no control group, and the serum hormone values are limited by the women's concurrent pill use. The journal is not indexed in PubMed.

Read the original source
Drugs@FDA, DailyMed and ClinicalTrials.gov, 10 October 2026: nothing; 2008 company statement: sold outside the US

Regulatory record

U.S. Food and Drug Administration, openFDA Drugs@FDA, DailyMed, U.S. National Library of Medicine, and ClinicalTrials.gov: searches run on 10 October 2026 for fluridil, topilutamide, Eucapil and NP-619. With a 2008 North Park Aesthetics press release (BioSpace copy).

openFDA Drugs@FDA returned no record and DailyMed returned no label for fluridil, topilutamide or Eucapil, and ClinicalTrials.gov returned no records for fluridil, topilutamide, Eucapil or NP-619, all on 10 October 2026. The 2006 clinical paper calls Eucapil a cosmetic product. A 2008 press release (company statement) said North Park Aesthetics acquired worldwide rights from Biophysica, Inc. and Interpharma Praha, named fluridil the main ingredient of NP-619 as its phase 2 product for androgenetic alopecia, and said Eucapil was sold outside the US. No NP-619 trial record or result was found.

Participants / model
Not a clinical population
Treatment
Drug applications, labels, registry, and a company press release
Follow-up
Searches run on 10 October 2026; press release from 2008
Study design
FDA record and registry searches, with a company press release (sponsor's own account)
Funding
not stated in the source

The absence of a US record is a US-scoped statement. Whether any fluridil product is currently marketed was not established beyond the 2006 paper and the 2008 company statement.

Read the original source
PubMed, 10 October 2026: 2 records; no replication, registered trial or study after 2006

PubMed search record

PubMed searches run on 10 October 2026: fluridil[tiab] OR Eucapil[tiab] OR "BP-766"[tiab] OR topilutamide[tiab] (2 records); fluridil androgenetic alopecia topical antiandrogen (1 record).

The first search returned 2 records: the 2002 male trial and a 2018 review of laboratory assays for nonsteroidal anti-androgens that lists topilutamide among first-generation antiandrogens. A broader search, fluridil androgenetic alopecia topical antiandrogen, returned 1 record, the same male trial. No randomized trial against minoxidil or finasteride, no registered trial, no independent replication, and no study after 2006 was found.

Participants / model
Records reviewed, not a population
Treatment
Not applicable
Follow-up
Searches run on 10 October 2026
Study design
Literature search
Funding
not stated in the source

A search result shows what PubMed returned on that date. It is not proof that no unindexed study exists.

Read the original source

What did the open study in women find?

In an open, uncontrolled 9-month study in 11 women taking a cyproterone acetate and ethinylestradiol pill, the anagen percentage did not change while hair stem diameter rose (P < 0.001 at 9 months). Two women stopped early for application-site itching and reddening or dryness.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil, 2% fluridil in anhydrous isopropanol applied daily, did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change). The authors attribute that to the prior antiandrogen use.

Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. The study has no control group, and the journal, Scripta Medica (Brno), is not indexed in PubMed.

Women: 11 on Eucapil for 9 months, anagen share unchanged, stem diameter up

Human study

Scripta Medica (Brno). 2006;79(1):35-48. Open, uncontrolled 9-month study of Eucapil in women. The journal is not indexed in PubMed.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil (2% fluridil in anhydrous isopropanol, applied daily) did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change), which the authors attribute to the prior antiandrogen use. Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. Two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA. Serum testosterone and SHBG were interpreted against the women's concurrent cyproterone acetate pill use, which limits what these values can show. The paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing.

Participants / model
11 women aged 22 to 45 with androgenetic alopecia (Ludwig stage I to II) on a cyproterone acetate and ethinylestradiol pill; serum data also cited from 40 men in earlier work
Treatment
Topical Eucapil (2% fluridil in anhydrous isopropanol) once daily
Follow-up
9 months
Study design
Open-label study, no control group
Funding
not stated in the source

The authors attribute the unchanged anagen percentage to the prior antiandrogen use. The study has no control group, and the serum hormone values are limited by the women's concurrent pill use. The journal is not indexed in PubMed.

Read the original source

Is fluridil absorbed into the blood?

No fluridil or its catabolites were found in serum at a 5 ng/mL limit in the 11-woman study, and earlier work cited by the paper found none at that limit in 40 men. That supports no detectable serum drug in small series, not proof of no systemic effect.

In the women's study, blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA.

The 43-man trial reports no fluridil or its decomposition product BP-34 in serum at 0, 3 or 90 days. Serum testosterone and SHBG in the women were interpreted against their concurrent cyproterone acetate pill use, which limits what those values can show. These are small series.

Women: 11 on Eucapil for 9 months, anagen share unchanged, stem diameter up

Human study

Scripta Medica (Brno). 2006;79(1):35-48. Open, uncontrolled 9-month study of Eucapil in women. The journal is not indexed in PubMed.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil (2% fluridil in anhydrous isopropanol, applied daily) did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change), which the authors attribute to the prior antiandrogen use. Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. Two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA. Serum testosterone and SHBG were interpreted against the women's concurrent cyproterone acetate pill use, which limits what these values can show. The paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing.

Participants / model
11 women aged 22 to 45 with androgenetic alopecia (Ludwig stage I to II) on a cyproterone acetate and ethinylestradiol pill; serum data also cited from 40 men in earlier work
Treatment
Topical Eucapil (2% fluridil in anhydrous isopropanol) once daily
Follow-up
9 months
Study design
Open-label study, no control group
Funding
not stated in the source

The authors attribute the unchanged anagen percentage to the prior antiandrogen use. The study has no control group, and the serum hormone values are limited by the women's concurrent pill use. The journal is not indexed in PubMed.

Read the original source
Men: 43 with AGA on 2% fluridil, anagen share 76% to 85%; patch test in 20 men

Clinical trial

Sovak M et al. Dermatol Surg. 2002;28(8):678-85. PMID 12174057.

After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation. In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind, placebo-controlled study of 2% fluridil, the anagen percentage on phototrichogram did not change in placebo subjects but rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months; former placebo subjects rose from 76% to 85% after 6 months on fluridil. The authors report normal sexual function, libido, hematology and blood chemistry throughout, and no fluridil or its decomposition product BP-34 in serum at 0, 3 or 90 days. The abstract gives no arm sizes, p values, hair counts or hair density, and it notes that at 3 months, in the spring, serum testosterone rose within the normal range equally in placebo and fluridil groups.

Participants / model
20 men (patch test); 43 men with androgenetic alopecia, Norwood II to Va
Treatment
Topical 2% fluridil solution in isopropanol, daily; forearm patches with 2, 4 and 6% fluridil
Follow-up
21-day patch test; 3-month blinded period, with follow-up to 9 months
Study design
Double-blind placebo-controlled study; arm sizes are not stated in the abstract
Funding
not stated in the source

The blinded, placebo-controlled period was 3 months in 43 men. The endpoint was anagen percentage, a hair-cycle proxy, not hair count or density. Because former placebo subjects were later treated with fluridil, data beyond the blinded period are not placebo-controlled. The PubMed record has no conflict-of-interest statement, and the first author is listed with Biophysica, Inc. in the 2006 paper, a company that the 2008 release names as a licensor of fluridil rights. No independent replication was found.

Read the original source

Does topilutamide avoid the systemic sexual effects of anti-androgens?

Partly supported by small developer-linked studies. Topical anti-androgen for androgenetic alopecia is accurate as a studied use. Avoiding systemic sexual effects rests on no detectable serum levels in small series and normal reported libido and sexual function in a 3-month, 43-man trial, not on an adequately powered or independent trial.

Sellers describe topilutamide (fluridil) as a topical anti-androgen for androgenetic alopecia that avoids systemic sexual side effects. The first part is accurate as a studied use: two small human studies tested 2% fluridil on the scalp.

The second part rests on no detectable serum drug at a 5 ng/mL limit in small series, and on normal libido and sexual function reported in a 3-month, 43-man trial, with no stated instrument in the abstract. No adequately powered or independent trial shows it, and no randomized trial against minoxidil or finasteride, no registered trial and no study after 2006 was found in a PubMed search on 10 October 2026.

Men: 43 with AGA on 2% fluridil, anagen share 76% to 85%; patch test in 20 men

Clinical trial

Sovak M et al. Dermatol Surg. 2002;28(8):678-85. PMID 12174057.

After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation. In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind, placebo-controlled study of 2% fluridil, the anagen percentage on phototrichogram did not change in placebo subjects but rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months; former placebo subjects rose from 76% to 85% after 6 months on fluridil. The authors report normal sexual function, libido, hematology and blood chemistry throughout, and no fluridil or its decomposition product BP-34 in serum at 0, 3 or 90 days. The abstract gives no arm sizes, p values, hair counts or hair density, and it notes that at 3 months, in the spring, serum testosterone rose within the normal range equally in placebo and fluridil groups.

Participants / model
20 men (patch test); 43 men with androgenetic alopecia, Norwood II to Va
Treatment
Topical 2% fluridil solution in isopropanol, daily; forearm patches with 2, 4 and 6% fluridil
Follow-up
21-day patch test; 3-month blinded period, with follow-up to 9 months
Study design
Double-blind placebo-controlled study; arm sizes are not stated in the abstract
Funding
not stated in the source

The blinded, placebo-controlled period was 3 months in 43 men. The endpoint was anagen percentage, a hair-cycle proxy, not hair count or density. Because former placebo subjects were later treated with fluridil, data beyond the blinded period are not placebo-controlled. The PubMed record has no conflict-of-interest statement, and the first author is listed with Biophysica, Inc. in the 2006 paper, a company that the 2008 release names as a licensor of fluridil rights. No independent replication was found.

Read the original source
Women: 11 on Eucapil for 9 months, anagen share unchanged, stem diameter up

Human study

Scripta Medica (Brno). 2006;79(1):35-48. Open, uncontrolled 9-month study of Eucapil in women. The journal is not indexed in PubMed.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil (2% fluridil in anhydrous isopropanol, applied daily) did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change), which the authors attribute to the prior antiandrogen use. Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. Two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA. Serum testosterone and SHBG were interpreted against the women's concurrent cyproterone acetate pill use, which limits what these values can show. The paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing.

Participants / model
11 women aged 22 to 45 with androgenetic alopecia (Ludwig stage I to II) on a cyproterone acetate and ethinylestradiol pill; serum data also cited from 40 men in earlier work
Treatment
Topical Eucapil (2% fluridil in anhydrous isopropanol) once daily
Follow-up
9 months
Study design
Open-label study, no control group
Funding
not stated in the source

The authors attribute the unchanged anagen percentage to the prior antiandrogen use. The study has no control group, and the serum hormone values are limited by the women's concurrent pill use. The journal is not indexed in PubMed.

Read the original source
PubMed, 10 October 2026: 2 records; no replication, registered trial or study after 2006

PubMed search record

PubMed searches run on 10 October 2026: fluridil[tiab] OR Eucapil[tiab] OR "BP-766"[tiab] OR topilutamide[tiab] (2 records); fluridil androgenetic alopecia topical antiandrogen (1 record).

The first search returned 2 records: the 2002 male trial and a 2018 review of laboratory assays for nonsteroidal anti-androgens that lists topilutamide among first-generation antiandrogens. A broader search, fluridil androgenetic alopecia topical antiandrogen, returned 1 record, the same male trial. No randomized trial against minoxidil or finasteride, no registered trial, no independent replication, and no study after 2006 was found.

Participants / model
Records reviewed, not a population
Treatment
Not applicable
Follow-up
Searches run on 10 October 2026
Study design
Literature search
Funding
not stated in the source

A search result shows what PubMed returned on that date. It is not proof that no unindexed study exists.

Read the original source

How does topilutamide work, and does the formulation matter?

Fluridil is an anti-androgen applied to the scalp, described as a locally acting androgen receptor antagonist. It is unstable in water, so the studied product was an anhydrous 2% solution in isopropanol, and a product that is not an anhydrous solution is not shown to match it.

Fluridil is an anti-androgen applied to the scalp, described as a locally acting androgen receptor antagonist. A PubMed search on 10 October 2026 returned a 2018 review of laboratory assays for nonsteroidal anti-androgens that lists topilutamide among first-generation antiandrogens. No half-life or Tmax is given in the sources reviewed, because no drug was detectable in serum at the 5 ng/mL limit.

The 2006 paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing. The male-study abstract describes fluridil as highly hydrophobic and hydrolytically degradable, and names BP-34 as its decomposition product. The studied product, Eucapil, was 2% fluridil in anhydrous isopropanol, so a vendor product that is not an anhydrous solution is not shown to match the studied one.

Men: 43 with AGA on 2% fluridil, anagen share 76% to 85%; patch test in 20 men

Clinical trial

Sovak M et al. Dermatol Surg. 2002;28(8):678-85. PMID 12174057.

After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation. In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind, placebo-controlled study of 2% fluridil, the anagen percentage on phototrichogram did not change in placebo subjects but rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months; former placebo subjects rose from 76% to 85% after 6 months on fluridil. The authors report normal sexual function, libido, hematology and blood chemistry throughout, and no fluridil or its decomposition product BP-34 in serum at 0, 3 or 90 days. The abstract gives no arm sizes, p values, hair counts or hair density, and it notes that at 3 months, in the spring, serum testosterone rose within the normal range equally in placebo and fluridil groups.

Participants / model
20 men (patch test); 43 men with androgenetic alopecia, Norwood II to Va
Treatment
Topical 2% fluridil solution in isopropanol, daily; forearm patches with 2, 4 and 6% fluridil
Follow-up
21-day patch test; 3-month blinded period, with follow-up to 9 months
Study design
Double-blind placebo-controlled study; arm sizes are not stated in the abstract
Funding
not stated in the source

The blinded, placebo-controlled period was 3 months in 43 men. The endpoint was anagen percentage, a hair-cycle proxy, not hair count or density. Because former placebo subjects were later treated with fluridil, data beyond the blinded period are not placebo-controlled. The PubMed record has no conflict-of-interest statement, and the first author is listed with Biophysica, Inc. in the 2006 paper, a company that the 2008 release names as a licensor of fluridil rights. No independent replication was found.

Read the original source
Women: 11 on Eucapil for 9 months, anagen share unchanged, stem diameter up

Human study

Scripta Medica (Brno). 2006;79(1):35-48. Open, uncontrolled 9-month study of Eucapil in women. The journal is not indexed in PubMed.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil (2% fluridil in anhydrous isopropanol, applied daily) did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change), which the authors attribute to the prior antiandrogen use. Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. Two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA. Serum testosterone and SHBG were interpreted against the women's concurrent cyproterone acetate pill use, which limits what these values can show. The paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing.

Participants / model
11 women aged 22 to 45 with androgenetic alopecia (Ludwig stage I to II) on a cyproterone acetate and ethinylestradiol pill; serum data also cited from 40 men in earlier work
Treatment
Topical Eucapil (2% fluridil in anhydrous isopropanol) once daily
Follow-up
9 months
Study design
Open-label study, no control group
Funding
not stated in the source

The authors attribute the unchanged anagen percentage to the prior antiandrogen use. The study has no control group, and the serum hormone values are limited by the women's concurrent pill use. The journal is not indexed in PubMed.

Read the original source
PubChem: topilutamide and fluridil are one record

Chemical identity record

National Library of Medicine. PubChem compound record CID 9930988 (topilutamide, fluridil).

Topilutamide and fluridil are one PubChem record: CID 9930988, C13H11F6N3O5, 403.23 g/mol, CAS 260980-89-0, with synonyms BP-766 and topilutamidum. IUPAC name 2-hydroxy-2-methyl-N-[4-nitro-3-(trifluoromethyl)phenyl]-3-[(2,2,2-trifluoroacetyl)amino]propanamide. The studied product, Eucapil, is a cosmetic solution of 2% fluridil in anhydrous isopropanol.

Participants / model
Chemical identity, not a clinical population
Treatment
Defined molecule
Follow-up
Not applicable
Study design
NLM chemical record
Funding
not stated in the source

Identity record only; it says nothing about efficacy or safety.

Read the original source
PubMed, 10 October 2026: 2 records; no replication, registered trial or study after 2006

PubMed search record

PubMed searches run on 10 October 2026: fluridil[tiab] OR Eucapil[tiab] OR "BP-766"[tiab] OR topilutamide[tiab] (2 records); fluridil androgenetic alopecia topical antiandrogen (1 record).

The first search returned 2 records: the 2002 male trial and a 2018 review of laboratory assays for nonsteroidal anti-androgens that lists topilutamide among first-generation antiandrogens. A broader search, fluridil androgenetic alopecia topical antiandrogen, returned 1 record, the same male trial. No randomized trial against minoxidil or finasteride, no registered trial, no independent replication, and no study after 2006 was found.

Participants / model
Records reviewed, not a population
Treatment
Not applicable
Follow-up
Searches run on 10 October 2026
Study design
Literature search
Funding
not stated in the source

A search result shows what PubMed returned on that date. It is not proof that no unindexed study exists.

Read the original source

What risks and side effects were reported?

Two of 11 women stopped early for application-site itching and reddening or dryness, which the authors attribute to the isopropanol. A 20-man patch test found no sensitization or irritation, but the studies are small, old and developer-linked, so long-term safety is unknown.

In the women's study, two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range. After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation.

The authors of the 43-man trial report normal sexual function, libido, hematology and blood chemistry throughout, with no stated instrument for sexual function in the abstract. The studies are small and old, both come from one group linked to a licensor of fluridil rights, and no independent safety data were found, so long-term and large-sample safety is unknown. The women's hormone values were measured while they took a cyproterone acetate and ethinylestradiol pill, which limits what they show.

Women: 11 on Eucapil for 9 months, anagen share unchanged, stem diameter up

Human study

Scripta Medica (Brno). 2006;79(1):35-48. Open, uncontrolled 9-month study of Eucapil in women. The journal is not indexed in PubMed.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil (2% fluridil in anhydrous isopropanol, applied daily) did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change), which the authors attribute to the prior antiandrogen use. Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. Two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA. Serum testosterone and SHBG were interpreted against the women's concurrent cyproterone acetate pill use, which limits what these values can show. The paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing.

Participants / model
11 women aged 22 to 45 with androgenetic alopecia (Ludwig stage I to II) on a cyproterone acetate and ethinylestradiol pill; serum data also cited from 40 men in earlier work
Treatment
Topical Eucapil (2% fluridil in anhydrous isopropanol) once daily
Follow-up
9 months
Study design
Open-label study, no control group
Funding
not stated in the source

The authors attribute the unchanged anagen percentage to the prior antiandrogen use. The study has no control group, and the serum hormone values are limited by the women's concurrent pill use. The journal is not indexed in PubMed.

Read the original source
Men: 43 with AGA on 2% fluridil, anagen share 76% to 85%; patch test in 20 men

Clinical trial

Sovak M et al. Dermatol Surg. 2002;28(8):678-85. PMID 12174057.

After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation. In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind, placebo-controlled study of 2% fluridil, the anagen percentage on phototrichogram did not change in placebo subjects but rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months; former placebo subjects rose from 76% to 85% after 6 months on fluridil. The authors report normal sexual function, libido, hematology and blood chemistry throughout, and no fluridil or its decomposition product BP-34 in serum at 0, 3 or 90 days. The abstract gives no arm sizes, p values, hair counts or hair density, and it notes that at 3 months, in the spring, serum testosterone rose within the normal range equally in placebo and fluridil groups.

Participants / model
20 men (patch test); 43 men with androgenetic alopecia, Norwood II to Va
Treatment
Topical 2% fluridil solution in isopropanol, daily; forearm patches with 2, 4 and 6% fluridil
Follow-up
21-day patch test; 3-month blinded period, with follow-up to 9 months
Study design
Double-blind placebo-controlled study; arm sizes are not stated in the abstract
Funding
not stated in the source

The blinded, placebo-controlled period was 3 months in 43 men. The endpoint was anagen percentage, a hair-cycle proxy, not hair count or density. Because former placebo subjects were later treated with fluridil, data beyond the blinded period are not placebo-controlled. The PubMed record has no conflict-of-interest statement, and the first author is listed with Biophysica, Inc. in the 2006 paper, a company that the 2008 release names as a licensor of fluridil rights. No independent replication was found.

Read the original source

Why does topilutamide sit in C tier?

C fits a plausible local mechanism and two small human studies, but the data are thin and old, come from one group linked to a licensor of fluridil rights, and have never been registered or replicated. No drug approval was found.

Two small human studies, one placebo-controlled in 43 men for 3 months, report a higher anagen share in men, no detectable serum drug at a 5 ng/mL limit, and normal sexual function in men. The male trial reports a hair-cycle proxy without arm sizes or p values, the women's study was open-label with no control group and showed no change in anagen share, and nothing has been registered or replicated in more than two decades.

The product is a cosmetic outside the US with no drug approval found. The supplier claim of avoiding systemic sexual effects is not shown by any adequately powered or independent trial.

Men: 43 with AGA on 2% fluridil, anagen share 76% to 85%; patch test in 20 men

Clinical trial

Sovak M et al. Dermatol Surg. 2002;28(8):678-85. PMID 12174057.

After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation. In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind, placebo-controlled study of 2% fluridil, the anagen percentage on phototrichogram did not change in placebo subjects but rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months; former placebo subjects rose from 76% to 85% after 6 months on fluridil. The authors report normal sexual function, libido, hematology and blood chemistry throughout, and no fluridil or its decomposition product BP-34 in serum at 0, 3 or 90 days. The abstract gives no arm sizes, p values, hair counts or hair density, and it notes that at 3 months, in the spring, serum testosterone rose within the normal range equally in placebo and fluridil groups.

Participants / model
20 men (patch test); 43 men with androgenetic alopecia, Norwood II to Va
Treatment
Topical 2% fluridil solution in isopropanol, daily; forearm patches with 2, 4 and 6% fluridil
Follow-up
21-day patch test; 3-month blinded period, with follow-up to 9 months
Study design
Double-blind placebo-controlled study; arm sizes are not stated in the abstract
Funding
not stated in the source

The blinded, placebo-controlled period was 3 months in 43 men. The endpoint was anagen percentage, a hair-cycle proxy, not hair count or density. Because former placebo subjects were later treated with fluridil, data beyond the blinded period are not placebo-controlled. The PubMed record has no conflict-of-interest statement, and the first author is listed with Biophysica, Inc. in the 2006 paper, a company that the 2008 release names as a licensor of fluridil rights. No independent replication was found.

Read the original source
Women: 11 on Eucapil for 9 months, anagen share unchanged, stem diameter up

Human study

Scripta Medica (Brno). 2006;79(1):35-48. Open, uncontrolled 9-month study of Eucapil in women. The journal is not indexed in PubMed.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil (2% fluridil in anhydrous isopropanol, applied daily) did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change), which the authors attribute to the prior antiandrogen use. Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. Two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA. Serum testosterone and SHBG were interpreted against the women's concurrent cyproterone acetate pill use, which limits what these values can show. The paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing.

Participants / model
11 women aged 22 to 45 with androgenetic alopecia (Ludwig stage I to II) on a cyproterone acetate and ethinylestradiol pill; serum data also cited from 40 men in earlier work
Treatment
Topical Eucapil (2% fluridil in anhydrous isopropanol) once daily
Follow-up
9 months
Study design
Open-label study, no control group
Funding
not stated in the source

The authors attribute the unchanged anagen percentage to the prior antiandrogen use. The study has no control group, and the serum hormone values are limited by the women's concurrent pill use. The journal is not indexed in PubMed.

Read the original source
Drugs@FDA, DailyMed and ClinicalTrials.gov, 10 October 2026: nothing; 2008 company statement: sold outside the US

Regulatory record

U.S. Food and Drug Administration, openFDA Drugs@FDA, DailyMed, U.S. National Library of Medicine, and ClinicalTrials.gov: searches run on 10 October 2026 for fluridil, topilutamide, Eucapil and NP-619. With a 2008 North Park Aesthetics press release (BioSpace copy).

openFDA Drugs@FDA returned no record and DailyMed returned no label for fluridil, topilutamide or Eucapil, and ClinicalTrials.gov returned no records for fluridil, topilutamide, Eucapil or NP-619, all on 10 October 2026. The 2006 clinical paper calls Eucapil a cosmetic product. A 2008 press release (company statement) said North Park Aesthetics acquired worldwide rights from Biophysica, Inc. and Interpharma Praha, named fluridil the main ingredient of NP-619 as its phase 2 product for androgenetic alopecia, and said Eucapil was sold outside the US. No NP-619 trial record or result was found.

Participants / model
Not a clinical population
Treatment
Drug applications, labels, registry, and a company press release
Follow-up
Searches run on 10 October 2026; press release from 2008
Study design
FDA record and registry searches, with a company press release (sponsor's own account)
Funding
not stated in the source

The absence of a US record is a US-scoped statement. Whether any fluridil product is currently marketed was not established beyond the 2006 paper and the 2008 company statement.

Read the original source
PubMed, 10 October 2026: 2 records; no replication, registered trial or study after 2006

PubMed search record

PubMed searches run on 10 October 2026: fluridil[tiab] OR Eucapil[tiab] OR "BP-766"[tiab] OR topilutamide[tiab] (2 records); fluridil androgenetic alopecia topical antiandrogen (1 record).

The first search returned 2 records: the 2002 male trial and a 2018 review of laboratory assays for nonsteroidal anti-androgens that lists topilutamide among first-generation antiandrogens. A broader search, fluridil androgenetic alopecia topical antiandrogen, returned 1 record, the same male trial. No randomized trial against minoxidil or finasteride, no registered trial, no independent replication, and no study after 2006 was found.

Participants / model
Records reviewed, not a population
Treatment
Not applicable
Follow-up
Searches run on 10 October 2026
Study design
Literature search
Funding
not stated in the source

A search result shows what PubMed returned on that date. It is not proof that no unindexed study exists.

Read the original source

Studies and sources

PubChem: topilutamide and fluridil are one record

Chemical identity record

National Library of Medicine. PubChem compound record CID 9930988 (topilutamide, fluridil).

Topilutamide and fluridil are one PubChem record: CID 9930988, C13H11F6N3O5, 403.23 g/mol, CAS 260980-89-0, with synonyms BP-766 and topilutamidum. IUPAC name 2-hydroxy-2-methyl-N-[4-nitro-3-(trifluoromethyl)phenyl]-3-[(2,2,2-trifluoroacetyl)amino]propanamide. The studied product, Eucapil, is a cosmetic solution of 2% fluridil in anhydrous isopropanol.

Participants / model
Chemical identity, not a clinical population
Treatment
Defined molecule
Follow-up
Not applicable
Study design
NLM chemical record
Funding
not stated in the source

Identity record only; it says nothing about efficacy or safety.

Read the original source
Drugs@FDA, DailyMed and ClinicalTrials.gov, 10 October 2026: nothing; 2008 company statement: sold outside the US

Regulatory record

U.S. Food and Drug Administration, openFDA Drugs@FDA, DailyMed, U.S. National Library of Medicine, and ClinicalTrials.gov: searches run on 10 October 2026 for fluridil, topilutamide, Eucapil and NP-619. With a 2008 North Park Aesthetics press release (BioSpace copy).

openFDA Drugs@FDA returned no record and DailyMed returned no label for fluridil, topilutamide or Eucapil, and ClinicalTrials.gov returned no records for fluridil, topilutamide, Eucapil or NP-619, all on 10 October 2026. The 2006 clinical paper calls Eucapil a cosmetic product. A 2008 press release (company statement) said North Park Aesthetics acquired worldwide rights from Biophysica, Inc. and Interpharma Praha, named fluridil the main ingredient of NP-619 as its phase 2 product for androgenetic alopecia, and said Eucapil was sold outside the US. No NP-619 trial record or result was found.

Participants / model
Not a clinical population
Treatment
Drug applications, labels, registry, and a company press release
Follow-up
Searches run on 10 October 2026; press release from 2008
Study design
FDA record and registry searches, with a company press release (sponsor's own account)
Funding
not stated in the source

The absence of a US record is a US-scoped statement. Whether any fluridil product is currently marketed was not established beyond the 2006 paper and the 2008 company statement.

Read the original source
Men: 43 with AGA on 2% fluridil, anagen share 76% to 85%; patch test in 20 men

Clinical trial

Sovak M et al. Dermatol Surg. 2002;28(8):678-85. PMID 12174057.

After a 21-day occlusive forearm patch test with 2, 4 and 6% fluridil in 20 men, the authors report neither fluridil nor isopropanol showed sensitization or irritation. In 43 men with androgenetic alopecia (Norwood II to Va) in a double-blind, placebo-controlled study of 2% fluridil, the anagen percentage on phototrichogram did not change in placebo subjects but rose from 76% to 85% on fluridil at 3 months and to 87% at 9 months; former placebo subjects rose from 76% to 85% after 6 months on fluridil. The authors report normal sexual function, libido, hematology and blood chemistry throughout, and no fluridil or its decomposition product BP-34 in serum at 0, 3 or 90 days. The abstract gives no arm sizes, p values, hair counts or hair density, and it notes that at 3 months, in the spring, serum testosterone rose within the normal range equally in placebo and fluridil groups.

Participants / model
20 men (patch test); 43 men with androgenetic alopecia, Norwood II to Va
Treatment
Topical 2% fluridil solution in isopropanol, daily; forearm patches with 2, 4 and 6% fluridil
Follow-up
21-day patch test; 3-month blinded period, with follow-up to 9 months
Study design
Double-blind placebo-controlled study; arm sizes are not stated in the abstract
Funding
not stated in the source

The blinded, placebo-controlled period was 3 months in 43 men. The endpoint was anagen percentage, a hair-cycle proxy, not hair count or density. Because former placebo subjects were later treated with fluridil, data beyond the blinded period are not placebo-controlled. The PubMed record has no conflict-of-interest statement, and the first author is listed with Biophysica, Inc. in the 2006 paper, a company that the 2008 release names as a licensor of fluridil rights. No independent replication was found.

Read the original source
Women: 11 on Eucapil for 9 months, anagen share unchanged, stem diameter up

Human study

Scripta Medica (Brno). 2006;79(1):35-48. Open, uncontrolled 9-month study of Eucapil in women. The journal is not indexed in PubMed.

An open, uncontrolled 9-month study enrolled 11 women aged 22 to 45 (average 35) with Ludwig stage I to II androgenetic alopecia who had taken the cyproterone acetate and ethinylestradiol product Diane 35 for at least 3 months (mean use almost 2.5 years). Eucapil (2% fluridil in anhydrous isopropanol, applied daily) did not change the anagen percentage (92.86% at baseline, 93.13% at 6 months, 92.69% at 9 months; no significant change), which the authors attribute to the prior antiandrogen use. Hair stem diameter rose significantly (P < 0.02 at 6 months and P < 0.001 at 9 months), and the diameter rose in all 9 patients measured at 9 months. Six women had mildly improved global scalp views at the end. Two women stopped early for itching and reddening or dryness at the application site, which the authors attribute to the isopropanol. Blood and biochemistry values stayed in the normal range, and no fluridil or its catabolites were found at the method limit of 5 ng/mL in any serum sample at enrollment or at 3, 6 and 9 months. Questionnaires covering libido, nipple tension and sexual function disturbances showed no reported change in general health. The paper cites earlier work finding no detectable drug at the same 5 ng/mL limit in 40 men with AGA. Serum testosterone and SHBG were interpreted against the women's concurrent cyproterone acetate pill use, which limits what these values can show. The paper says the active ingredient is unstable in an aqueous setting, so the study kept the product to dry-scalp application with limits on shampooing.

Participants / model
11 women aged 22 to 45 with androgenetic alopecia (Ludwig stage I to II) on a cyproterone acetate and ethinylestradiol pill; serum data also cited from 40 men in earlier work
Treatment
Topical Eucapil (2% fluridil in anhydrous isopropanol) once daily
Follow-up
9 months
Study design
Open-label study, no control group
Funding
not stated in the source

The authors attribute the unchanged anagen percentage to the prior antiandrogen use. The study has no control group, and the serum hormone values are limited by the women's concurrent pill use. The journal is not indexed in PubMed.

Read the original source

Why is Topilutamide (fluridil) in C tier?

C fits a plausible local mechanism and two small human studies, one placebo-controlled in 43 men for 3 months, that report a higher anagen share in men, no detectable serum drug at a 5 ng/mL limit and normal sexual function. The data are thin and old: the male trial reports a hair-cycle proxy without arm sizes or p values, the women's study was open-label with no control and showed no change in anagen share, nothing has been registered or replicated in more than two decades, and the product is a cosmetic outside the US with no drug approval found.