Pyrilutamide (developmental code name KX-826) is a nonsteroidal antiandrogen (NSAA) – specifically, a selective high-affinity silent antagonist of the androgen receptor (AR) – which is under development by Suzhou Kintor Pharmaceuticals, inc., a subsidiary of Kintor Pharmaceutical Limited, for the potential treatment of androgenic alopecia (androgen-dependent scalp hair loss)[1][2][3] As of October 2022, it is in phase 3 clinical trials for androgenic alopecia and phase 2 trials for acne.[2]

Development

The primary endpoint is the change from baseline in non-vellus target area hair count (TAHC) at the end of week 24. The drug will be dosed at 10 mg (0.5% BID) per patient per day in the trial.[4]

Adverse effects

Pyrilutamide is generally well-tolerated. The most common adverse event is contact dermatitis.[5]

Pharmacology

Plasma concentration of pyrilutamide and metabolite KX-982 in different dose groups in phase Ib clinical trials in China

Pharmacodynamics

Pyrilutamide binds to the androgen receptor with a very high affinity with an IC50 of 0.28 nM. [3] Reference drug bicalutamide had an IC50 of 3.1 nM. [3]

References

  1. ^ Saceda-Corralo D, Domínguez-Santas M, Vañó-Galván S, Grimalt R (January 2023). "What's New in Therapy for Male Androgenetic Alopecia?". American Journal of Clinical Dermatology. 24 (1): 15–24. doi:10.1007/s40257-022-00730-y. PMID 36169916.
  2. ^ a b "Pyrilutamide - Suzhou Kintor Pharmaceuticals". AdisInsight. Springer Nature Switzerland AG.
  3. ^ a b c CA patent 2829322, Tong Y, "Substituted Thioimidazolidinone Androgen Receptor Antagonists and Uses Thereof", published 2012-03-08, issued 2017-01-10, assigned to Suzhou Kintor Pharmaceuticals, Inc 
  4. ^ "Kintor Pharma Announces the Primary Endpoint of Phase II Clinical Study for KX-826's Treatment of Androgenetic Alopecia Was Met".
  5. ^ "Kintor Pharmaceutical (9939 HK) Specializing in AR-related innovative therapies" (PDF).