Category Archives: Androgen Receptors

Silencing the Androgen Receptor Gene via siRNA

siRNA Androgen Receptor Gene Silencing
Using siRNA to silence the androgen receptor gene and thereby cause hair regrowth. Source: Journal of Medicinal Chemistry.

I have covered small interfering ribonucleic acid (siRNA) and its significant hair growth potential a number of times on this blog. In particular, two posts stand out:

  1. In 2023, Bioneer (South Korea) via its siRNAgen subsidiary released a siRNA based topical hair growth cosmeceutical product called CosmeRNA. It targets the androgen receptor (AR) via self-assembled micelle inhibitory RNA (SAMiRNA) nanoparticle-type siRNA. More details about this product can be read in a Nature magazine study from January 2022.
  2. In 2025, OliX Pharmaceuticals (South Korea) filed a Phase 1b/2a clinical trial plan for its hair loss treatment candidate OLX104C. This drug uses asymmetric siRNA to inhibit male pattern hair loss gene expression. Scientists from the company published a detailed study about this in 2022 titled: “Efficacy of asymmetric siRNA targeting androgen receptors for the treatment of androgenetic alopecia.”

Silencing the Androgen Receptor Gene via siRNAs for Androgenetic Alopecia Therapy

And now in October 2025, we got another new study that finds siRNAs to be of use in treating hair loss. This one is from China and is titled: “Efficient silencing of androgen receptor gene via UTR-targeting siRNAs for androgenetic alopecia therapy”. The “UTR” stands for “untranslated regions”.

The Chinese scientists screened a series of siRNA sequences targeting the non-coding region of the androgen receptor gene. They then identified a lead siRNA candidate (AR-27) that is conserved between Homo sapiens and Mus musculus (the house mouse).

Subsequently, they evaluated the chemically modified and cholesterol-conjugated candidate (AR-27 E-Chol) in both cells and in a DHT-induced AGA mice model. It was found that AR-27 E-Chol stimulated dorsal hair regrowth and significantly downregulated AR gene expression in skin tissues. Their conclusion:

“These findings support the clinical potential of AR-27 E-Chol as an effective therapeutic candidate for AGA.”

Note that AR-27 E-Chol does not bind to the androgen receptor (as is the case with existing anti-androgens). Nor does it alter any hormones, such as dihydrotestosterone (DHT), testosterone of estrogen (as is the case with hair loss drugs finasteride and dutasteride). Instead, it directly silences the androgen receptor gene. And it is given topically rather than orally or via injection. The effect will be localized to the area of the scalp where the gel is applied. And it seems like there will be no side effects or systemic absorption.

I was not planning to write an entire post on this study, till reader “Alvaro” posted the below embedded recent auto-dubbed video. It is a presentation by Dr. Oscar Muñoz Moreno-Arrones from Spain, who has become an important influencer in the hair loss world. For his main job, he is a dermatologist and a hair transplant surgeon based in Madrid per his website. One interesting thing that the doctor mentions is that this topical gel might even stop your beard growth if applied to the face.

KX-826 (Pyrilutamide) Cosmetic Launched

Price Drop Alert — The new Kintor Green Version with 0.5% KX-826 plus various natural ingredients is currently on sale for almost 70% off (after including the coupon option below the discounted price). So it will cost just $28 after taxes. Very strange, as the other two products are not similarly discounted.


See my regularly updated post on China-based Kintor Pharmaceutical’s clinical trials for their two main topical androgen receptor targeting products. Both may come out in the next few years if Phase 3 trials are successful.

Meanwhile, the company launched a KX-826 (Pyrilutamide) based cosmetic product in 2024 after receiving International Nomenclature Cosmetic Ingredient (INCI) approval.

Update: June 2025

Kintor now sells three versions of its KX-826 spray for hair loss.

  • The purple version with 0.9% KX-826.
  • The blue version with 0.5% KX-826.
  • The new green version with 0.5% KX-826. It comes with a plant-based extract essence that promotes scalp blood circulation and nutrition to hair follicles. The full list of natural ingredients can be seen here.
Kintor KX-826 Spray
The Kintor KX-826 spray for hair loss now comes in three versions.

July 26, 2024

KX-826 Hair Growth Spray Launched

The blue version is priced at $69 for a 1-month supply (plus a 5% off coupon) and contains 0.5% KX-826 (pyrilutamide). Update: The enhanced 0.9% KX-826 purple version is also on Amazon now. Both are made by Koshine Biomedica (China) in Hong Kong.

Each product comes as a topical spray. There are no reviews or product ratings at the time of writing this post. The product description mentions that it is a dihydrotestosterone (DHT) blocker, and reduces sebum excretion and scalp oiliness.

Note that the actual androgen receptor antagonist KX-826 is still in Phase 3 clinical trials in the US and China. The cosmetic product (image below) is a way for the company to release a topical product faster.

Kintor KX-826 Cosmetic
Kintor Pharmaceutical (China)’s KX-826 Cosmetic Androgen Receptor Antagonist. Made by Koshine Biomedica (China).

Also of interest, one of the images on Amazon implies more rapid hair growth from this spray product in comparison to FDA approved Minoxidil:

KX-826 versus Minoxidil
KX-826 versus Minoxidil hair growth comparison.

Usage Instructions

The instructions on using this KX-826 spray are as follows:

  1. Open the outer packaging and insert the spray head onto the bottle.
  2. Find your area of hair loss, use your fingers to expose the scalp, and then apply th30e anti-hair loss liquid spray.
  3. Use once in the morning and once in the evening. For a total of 6-8 sprays each time, which equates to about 1ml.
  4. Massage the scalp for about 3 minutes after the spray has been applied.

Note: Only meant to be used when your scalp and hair are both dry.