What were the KX-826 Phase 3 results?

In March 2026 Kintor reported that the Phase 3 stage of its China pivotal trial met its primary endpoint. In 666 men treated for 24 weeks, target-area non-vellus hair count rose by 15.33 hairs/cm² at 1.0% twice daily and 14.46 at 0.5% twice daily, versus 4.68 for vehicle, a placebo-adjusted gain of about 10.65 and 9.78 hairs/cm² respectively (p below 0.0001). No drug-related serious adverse events were reported.

Has pyrilutamide been approved anywhere?

No. As of October 2026 there is no marketing authorisation for pyrilutamide in any country. Kintor has said it plans to file a new drug application in China following the Phase 3 result. Until a regulator approves it, it remains an investigational drug, and outside a trial it exists only as a research chemical.

Did the US Phase 2 trial fail?

It is unclear, and that is the honest answer. Kintor's May 2023 release on the 123-man US Phase 2 reported a statistically significant gain from baseline at 0.5% twice daily (about 10 hairs/cm², p=0.0088) but only said hair counts 'indicated an improvement' versus placebo, with no placebo-adjusted p value. A result reported that way is usually one that did not reach significance against placebo.

How does the Phase 3 result compare to minoxidil and finasteride?

Cautiously. Cross-trial comparisons are unreliable because populations, counting methods and durations differ. The 2022 JAMA Dermatology network meta-analysis of 23 studies found oral dutasteride and finasteride ahead of topical minoxidil on 24-week hair count, with differences between agents of roughly 7 to 15 hairs/cm². KX-826's 10.65 placebo-adjusted gain is a clinically meaningful figure in that landscape, but not a ranking against any of them.

Are the KX-826 trial results peer reviewed?

Mostly not. The Phase 2 and Phase 3 results so far exist as company press releases and stock exchange announcements. A full peer-reviewed publication of the pivotal trial has not appeared as of October 2026. Press-release data is real data, but it has not been checked by independent reviewers.

Does the trial data apply to pyrilutamide sold as a research chemical?

No. The trials tested Kintor's pharmaceutical tincture at defined concentrations under medical supervision. Research-grade pyrilutamide from any supplier, including Norwood Labs, is not that product and is not sold for human use. The trial data tells you about the molecule's biology, not about the safety of any material outside the trial.

Pyrilutamide (KX-826) Clinical Trial Results

Key facts (as of October 2026)

China male Phase 2 (reported September 2021): 120 men, primary endpoint met at week 24.
China female Phase 2 (reported December 2022): 160 women, placebo-adjusted gain of 11.39 hairs/cm² at 0.5% (p=0.0087).
US Phase 2 (reported May 2023): 123 men, change from baseline reported but no statistically significant placebo-adjusted result.
China pivotal trial, Phase 3 stage (reported March 2026): 666 men, 10.65 hairs/cm² placebo-adjusted gain at 24 weeks.
No drug-related serious adverse events were reported in the Phase 3 stage.
No US Phase 3 had started and no marketing authorisation existed anywhere as of October 2026.

The short version

Pyrilutamide (KX-826) is the only topical androgen receptor antagonist with a positive Phase 3 result: in March 2026 Kintor reported a 10.65 hairs/cm² placebo-adjusted gain at 24 weeks in 666 Chinese men, with no drug-related serious adverse events.
Earlier trials were mixed: China Phase 2 positive (2021), China female Phase 2 positive (2022), US Phase 2 reported only as a gain from baseline with no placebo-adjusted significance (2023).
Nothing is approved anywhere yet, and the data is company-reported rather than peer reviewed. Promising, not proven.

Why this page exists

Pyrilutamide is unusual in this niche. RU-58841 was shelved before a single human trial completed. Clascoterone's hair-loss programme is still unreported in detail. Pyrilutamide, developed by Kintor Pharmaceutical in Suzhou, has gone through a full clinical programme in two countries, and most of what circulates online is a half-remembered version of one or two press releases. This page lists every trial Kintor has reported, in order, with the numbers as the company stated them and a note on what was left out. For what the molecule is and how it works, start with What is pyrilutamide?

1. China Phase 2, male AGA (reported September 2021)

A multicentre, randomised, double-blind, placebo-controlled study in 120 Chinese men. The primary endpoint was change from baseline in target-area non-vellus hair count (TAHC) at week 24 versus placebo. Kintor announced that the endpoint was met with a statistically significant and clinically meaningful result, that most adverse events were mild with no serious adverse events, and that 0.5% was selected for Phase 3 [1]. The release did not give the hair-count figures. That omission is the pattern to watch for across this programme: endpoints are announced; full tables often are not.

2. China Phase 2, female AGA (reported December 2022)

160 women with Savin scale D3 to D6 hair loss were randomised across four KX-826 arms and placebo. At 24 weeks the 0.5% once-daily arm showed a placebo-adjusted TAHC gain of 11.39 hairs/cm² (p=0.0087), with efficacy visible from week 12. Most treatment-emergent adverse events were mild and similar to placebo, and none led to withdrawal [2]. This is one of very few controlled results for any antiandrogen in female pattern hair loss, where oral 5-alpha-reductase inhibitors are generally avoided.

3. US Phase 2, male AGA (reported May 2023)

This is the trial that complicates the story. 123 American men with Hamilton-Norwood III vertex, IV or V hair loss were randomised to 0.25% once daily, 0.5% once daily, 0.5% twice daily or placebo. Kintor's release stated that the 0.5% twice-daily group gained about 10 hairs/cm² from baseline at 24 weeks (p=0.0088), that KX-826 "indicated an improvement" versus placebo with a dose-response relationship, and that adverse events were mostly mild scalp sensitivity [3]. What the release does not contain is a placebo-adjusted difference or a p value for the primary comparison against placebo. Trials that beat placebo say so. The community reads this as a miss on the primary endpoint, and that reading is reasonable, though the company never used the word. No US Phase 3 has started.

4. China long-term safety Phase 3 (reported March 2025)

An open-label, 16-centre, 52-week study of 0.5% twice daily, with incidence of treatment-emergent adverse events as the primary endpoint. Kintor reported low overall adverse-event incidence, no deaths and no drug-related sexual dysfunction. As secondary measures, 46% of patients gained at least 10 hairs/cm² from baseline and 20% gained at least 20; investigator-rated improvement was seen in 53% of men and 48% of women [4]. Open-label and uncontrolled, so the efficacy numbers are soft, but a year of exposure data without a systemic antiandrogen signal is the main value of this study.

5. Observational combination study with minoxidil (reported May 2025)

A small open-label, randomised study in 75 Chinese men designed to inform Phase 3 planning. KX-826 0.5% twice daily plus minoxidil 5% twice daily produced a TAHC gain of 30.54 hairs/cm² from baseline at 24 weeks, about 10.29 hairs/cm² more than minoxidil alone [5]. Two centres, no blinding, company-reported, but the first controlled signal that a topical AR antagonist adds to minoxidil rather than merely matching it. See RU58841 vs minoxidil for why that matters mechanistically.

6. China pivotal trial, Phase 2 stage (reported July 2025)

Kintor redesigned its pivotal programme as a seamless Phase 2/3 with adaptive design, testing 1.0% and 0.5% twice daily against vehicle. The Phase 2 stage enrolled 90 men. At 24 weeks the 0.5% arm gained 22.39 hairs/cm² from baseline and the 1.0% arm 21.87, against 8.73 for placebo: placebo-adjusted gains of 13.66 (p=0.002) and 13.14 (p=0.004). No drug-related sexual adverse events were seen, and the independent data monitoring committee recommended proceeding to Phase 3 without changes [6].

7. China pivotal trial, Phase 3 stage (reported March 2026)

The headline result. 666 men across 26 centres, randomised, double-blind, vehicle-controlled, 24 weeks of treatment. TAHC rose by 15.33 hairs/cm² from baseline at 1.0% twice daily and 14.46 at 0.5% twice daily, versus 4.68 for placebo. The placebo-adjusted gains were 10.65 and 9.78 hairs/cm² respectively, both p below 0.0001. No drug-related serious adverse events occurred, and adverse-event rates did not differ meaningfully between active and placebo arms [7]. Kintor said it intends to begin a new drug application in China for the 1.0% tincture, and noted that Cosmo Pharmaceuticals' clascoterone, which targets the same receptor, reported positive Phase 3 results in December 2025 and is seeking US and EU approval.

What the numbers mean, and what they do not

Three honest observations. First, the placebo-adjusted effect shrank from about 13 hairs/cm² in the 90-patient Phase 2 stage to about 10 in the 666-patient Phase 3 stage. That is normal; small studies overestimate, and 10 hairs/cm² over placebo at 24 weeks is a real effect. For scale, Gupta and colleagues' 2022 network meta-analysis of 23 studies found differences between the licensed agents (dutasteride, finasteride, oral and topical minoxidil) of roughly 7 to 15 hairs/cm² at 24 weeks, so KX-826's effect sits in the range where approved treatments operate, without being directly comparable to any of them [8]. Second, none of this is peer reviewed yet. Press releases and posters are where the field sees data first, but the full tables, dropout handling and secondary endpoints have not been examined by independent reviewers. Third, the one trial outside China did not report a placebo-adjusted win. A single country's regulator may be satisfied; a global claim is not yet supportable.

Safety across the programme

The consistent finding in every release is mild, local adverse events (scalp sensitivity, irritation) at rates similar to placebo, with no drug-related sexual dysfunction in any trial including the 52-week open-label study. That is the result a topical AR antagonist is designed to deliver: receptor occupancy in the skin, rapid clearance of what gets through. It is also company-reported, and the absence of a signal in a few hundred men over a year is not the same as long-term safety established. We go through the adverse-event detail in Pyrilutamide side effects.

What this means for research material

Trial data describes Kintor's pharmaceutical tincture, applied under protocol, to people screened and monitored by investigators. It does not describe pyrilutamide powder or solution sold as a research chemical, by Norwood Labs or anyone else. We publish sample reports from a third-party analytical laboratory so researchers can see what the named samples contained; those reports say nothing about safety or efficacy in humans, and our material is supplied for laboratory research only. For how pyrilutamide sits against the other compound in this niche, read RU-58841 vs pyrilutamide.

References

Kintor Pharmaceutical. Kintor Pharma announces the primary endpoint of Phase II clinical study for KX-826's treatment of androgenetic alopecia was met. Press release, 8 September 2021. EQS News
Kintor Pharmaceutical. Primary endpoint of Phase II clinical study for KX-826's treatment of female androgenetic alopecia in China was met. Press release, 1 December 2022. kintor.com.cn
Kintor Pharmaceutical. Successful completion of Phase II clinical trial of KX-826 for treatment of androgenetic alopecia in the US. Press release, 11 May 2023. kintor.com.cn
Kintor Pharmaceutical. Long-term safety Phase III clinical trial of KX-826 for the treatment of AGA reached primary endpoint. Press release, 20 March 2025. kintor.com.cn
Kintor Pharmaceutical. Superior efficacy of clinical observational study in KX-826 in combination with minoxidil over minoxidil monotherapy. Press release, 2 May 2025. kintor.com.cn
Kintor Pharmaceutical. Phase II stage of pivotal clinical trial of KX-826 tincture 1.0% for male AGA reached primary endpoint. Press release, 24 July 2025. kintor.com.cn
Kintor Pharmaceutical. Phase III KX-826 tincture 1.0% for AGA reached primary endpoint. Press release, 18 March 2026. kintor.com.cn
Gupta AK, Venkataraman M, Talukder M, Bamimore MA. Relative efficacy of minoxidil and the 5-α reductase inhibitors in androgenetic alopecia treatment of male patients: a network meta-analysis. JAMA Dermatol. 2022;158(3):266-274. PMC8811710