Masofaniten

Masofaniten
Clinical data
Other namesEPI-7386
Routes of
administration		By mouth
Drug classN-Terminal domain antiandrogen
Identifiers
  • ''N''-[4-[[4-[2-[3-chloro-4-(2-chloroethoxy)-5-cyanophenyl]propan-2-yl]phenoxy]methyl]pyrimidin-2-yl]methanesulfonamide
CAS Number
PubChem CID
ChemSpider
UNII
ChEMBL
Chemical and physical data
FormulaC24H24Cl2N4O4S
Molar mass535.44 g·mol−1
3D model (JSmol)
  • CC(C)(C1=CC=C(C=C1)OCC2=NC(=NC=C2)NS(=O)(=O)C)C3=CC(=C(C(=C3)Cl)OCCCl)C#N
  • InChI=1S/C24H24Cl2N4O4S/c1-24(2,18-12-16(14-27)22(21(26)13-18)33-11-9-25)17-4-6-20(7-5-17)34-15-19-8-10-28-23(29-19)30-35(3,31)32/h4-8,10,12-13H,9,11,15H2,1-3H3,(H,28,29,30)
  • Key:GVCZSODXLFBYSS-UHFFFAOYSA-N

Masofaniten, also known by its developmental code name EPI-7386, is an N-terminal domain antiandrogen, or antagonist of the N-terminal domain (NTD) of the androgen receptor (AR), which was under development for the treatment of prostate cancer. The development of masofaniten has been discontinuted.

Development history

The compound was developed as a successor of previous drugs in the EPI series such as EPI-001, ralaniten (EPI-002), and ralaniten acetate (EPI-506). Masofaniten showed a 20-fold improved potency than ralaniten in vitro (IC50Tooltip Half-maximal inhibitory concentration = 535 nM vs. 9,580 nM, respectively), as well as greater stability in human hepatocytes.

It entered phase I clinical trials in 2020. Preliminary results of a phase I/II clinical trial were published in 2023. A combination of masofaniten and enzalutamide (ClinicalTrials.gov Identifier: NCT06312670) was tested in clinical trials for treatment-naïve metastatic hormone-sensitive prostate cancer and showed efficacy with an acceptable safety profile suggesting that further investigation was warranted.

The development of masofaniten was discontinued by ESSA Pharma Inc in 2024 .

References

  1. 1 2 "Masofaniten". AdisInsight. 9 October 2025. Retrieved 15 October 2025.
  2. 1 2 3 Le Moigne R, Banuelos CA, Mawji NR, Tam T, Wang J, Jian K, et al. (2020). "IND candidate EPI-7386 as an N-terminal domain androgen receptor inhibitor in development for the treatment of prostate cancer". Journal of Clinical Oncology. 38 (6_suppl): 142. doi:10.1200/JCO.2020.38.6_suppl.142. S2CID 213003338.
  3. 1 2 3 Moigne R, Zhou HJ, Mawji NR, Banuelos CA, Wang J, Jian K, et al. (2019). "Next generation N-terminal domain androgen receptor inhibitors with improved potency and metabolic stability in castration-resistant prostate cancer models". Journal of Clinical Oncology. 37 (7_suppl): 220. doi:10.1200/JCO.2019.37.7_suppl.220. ISSN 0732-183X. S2CID 88047727.
  4. 1 2 3 4 Sadar MD (May 2020). "Discovery of drugs that directly target the intrinsically disordered region of the androgen receptor". Expert Opinion on Drug Discovery. 15 (5): 551–560. doi:10.1080/17460441.2020.1732920. PMC 8693730. PMID 32100577. S2CID 211523793.
  5. ↑ Laccetti AL, Chatta GS, Iannotti N, Kyriakopoulos C, Villaluna K, Le Moigne R, et al. (2023-02-20). "Phase 1/2 study of EPI-7386 in combination with enzalutamide (enz) compared with enz alone in subjects with metastatic castration-resistant prostate cancer (mCRPC)". Journal of Clinical Oncology. 41 (6_suppl): 179. doi:10.1200/JCO.2023.41.6_suppl.179. ISSN 0732-183X. S2CID 257549466.
  6. ↑ Laccetti AL, Chatta G, Kyriakopoulos C, Iannotti N, Hotte SJ, Markowski MC, et al. (2023). "1813P Phase I/II trial of oral EPI-7386 in combination with enzalutamide (enz) compared to enz alone in metastatic castration-resistant prostate cancer (mCRPC) subjects: Current phase I (PI) results". Annals of Oncology. 34: S982–S983. doi:10.1016/j.annonc.2023.09.2761. S2CID 264383200.
  7. 1 2 Jang A, Fowler P, Helminiak K, Kumar HL, Pasucal J, Delong V, et al. (January 2026). "EXTRA-PC: a phase II trial of masofaniten (EPI-7386) and enzalutamide for patients with treatment-naïve metastatic hormone-sensitive prostate cancer". The Oncologist. 31 (2) oyaf434. doi:10.1093/oncolo/oyaf434. PMC 12861977. PMID 41467749.
  8. ↑ Rashid A (4 November 2024). "ESSA Pharma Pulls Plug on Masofaniten Prostate Cancer Drug After Disappointing Trial Results Against Xtandi". Xtalks. Retrieved 15 October 2025.