Ralaniten acetate

Last updated
Ralaniten acetate
Ralaniten acetate.svg
Clinical data
Other namesEPI-506
Routes of
administration
By mouth
Drug class Nonsteroidal antiandrogen
Identifiers
  • (2S)-3-[4-(2-[4-[(2S)-2-(Acetyloxy)-3-chloropropoxy]phenyl]propan-2-yl)phenoxy]propane-1,2-diyl diacetate
CAS Number
UNII
KEGG
Chemical and physical data
Formula C27H33ClO8
Molar mass 521.00 g·mol−1

Ralaniten acetate (developmental code name EPI-506) is a first-in-class antiandrogen that targets the N-terminal domain (NTD) of the androgen receptor (AR) developed by ESSA Pharmaceuticals and was under investigation for the treatment of prostate cancer. [1] [2] This mechanism of action is believed to allow the drug to block signaling from the AR and its splice variants. [3] [4] EPI-506 is a derivative of bisphenol A [5] and a prodrug of ralaniten (EPI-002), one of the four stereoisomers of EPI-001, and was developed as a successor of EPI-001. [6] The drug reached phase I/II prior to the discontinuation of its development. [1] It showed signs of efficacy in the form of prostatic specific antigen (PSA) decreases (4–29%) predominantly at higher doses (≥1,280 mg) in some patients but also caused side effects and was discontinued by its developer in favor of next-generation AR NTD inhibitors with improved potency and tolerability. [7]

Contents

See also

Related Research Articles

<span class="mw-page-title-main">Antiandrogen</span> Class of pharmaceutical drugs

Antiandrogens, also known as androgen antagonists or testosterone blockers, are a class of drugs that prevent androgens like testosterone and dihydrotestosterone (DHT) from mediating their biological effects in the body. They act by blocking the androgen receptor (AR) and/or inhibiting or suppressing androgen production. They can be thought of as the functional opposites of AR agonists, for instance androgens and anabolic steroids (AAS) like testosterone, DHT, and nandrolone and selective androgen receptor modulators (SARMs) like enobosarm. Antiandrogens are one of three types of sex hormone antagonists, the others being antiestrogens and antiprogestogens.

<span class="mw-page-title-main">Abiraterone acetate</span> Chemical compound

Abiraterone acetate, sold under the brand name Zytiga among others, is a medication used to treat prostate cancer. Specifically it is used together with a corticosteroid for metastatic castration-resistant prostate cancer (mCRPC) and metastatic high-risk castration-sensitive prostate cancer (mCSPC). It should either be used following removal of the testicles or along with a gonadotropin-releasing hormone (GnRH) analog. It is taken by mouth.

<span class="mw-page-title-main">Enzalutamide</span> Antiandrogen medication used in treatment of prostate cancer

Enzalutamide, sold under the brand name Xtandi, is a nonsteroidal antiandrogen (NSAA) medication which is used in the treatment of prostate cancer. It is indicated for use in conjunction with castration in the treatment of metastatic castration-resistant prostate cancer (mCRPC), nonmetastatic castration-resistant prostate cancer, and metastatic castration-sensitive prostate cancer (mCSPC). It is taken by mouth.

<span class="mw-page-title-main">Cabazitaxel</span> Chemical compound

Cabazitaxel, sold under the brand name Jevtana, is a semi-synthetic derivative of a natural taxoid. It is a microtubule inhibitor, and the fourth taxane to be approved as a cancer therapy.

The first antiandrogen was discovered in the 1960s. Antiandrogens antagonise the androgen receptor (AR) and thereby block the biological effects of testosterone and dihydrotestosterone (DHT). Antiandrogens are important for men with hormonally responsive diseases like prostate cancer, benign prostatic hyperplasia (BHP), acne, seborrhea, hirsutism and androgen alopecia. Antiandrogens are mainly used for the treatment of prostate diseases. Research from 2010 suggests that ARs could be linked to the disease progression of triple-negative breast cancer and salivary duct carcinoma and that antiandrogens can potentially be used to treat it.

<span class="mw-page-title-main">Galeterone</span> Chemical compound

Galeterone is a steroidal antiandrogen which was under development by Tokai Pharmaceuticals for the treatment of prostate cancer. It possesses a unique triple mechanism of action, acting as an androgen receptor antagonist, androgen receptor down regulator, and CYP17A1 inhibitor, the latter of which prevents the biosynthesis of androgens. As a CYP17A1 inhibitor, galeterone shows selectivity for 17,20-lyase over 17α-hydroxylase.

EPI-001 is the first inhibitor of the androgen receptor amino-terminal domain. The single stereoisomer of EPI-001, EPI-002, is a first-in-class drug that the USAN council assigned a new stem class "-aniten" and the generic name "ralaniten". This distinguishes the anitens novel molecular mechanism from anti androgens that bind the C-terminus ligand-binding domain and have the stem class "lutamide". EPI-001 and its stereoisomers and analogues were discovered by Marianne Sadar and Raymond Andersen, who co-founded the pharmaceutical company ESSA Pharma Inc for the clinical development of anitens for the treatment of castration-resistant prostate cancer (CRPC).

<span class="mw-page-title-main">Nonsteroidal antiandrogen</span>

A nonsteroidal antiandrogen (NSAA) is an antiandrogen with a nonsteroidal chemical structure. They are typically selective and full or silent antagonists of the androgen receptor (AR) and act by directly blocking the effects of androgens like testosterone and dihydrotestosterone (DHT). NSAAs are used in the treatment of androgen-dependent conditions in men and women. They are the converse of steroidal antiandrogens (SAAs), which are antiandrogens that are steroids and are structurally related to testosterone.

<span class="mw-page-title-main">Seviteronel</span> Chemical compound

Seviteronel is an experimental cancer medication which is under development by Viamet Pharmaceuticals and Innocrin Pharmaceuticals for the treatment of prostate cancer and breast cancer. It is a nonsteroidal CYP17A1 inhibitor and works by inhibiting the production of androgens and estrogens in the body. As of July 2017, seviteronel is in phase II clinical trials for both prostate cancer and breast cancer. In January 2016, it was designated fast-track status by the United States Food and Drug Administration for prostate cancer. In April 2017, seviteronel received fast-track designation for breast cancer as well.

Darolutamide, sold under the brand name Nubeqa, is an antiandrogen medication which is used in the treatment of non-metastatic castration-resistant prostate cancer in men. It is specifically approved to treat non-metastatic castration-resistant prostate cancer (nmCRPC) in conjunction with surgical or medical castration. The medication is taken by mouth twice per day with food.

<span class="mw-page-title-main">Apalutamide</span> Chemical compound

Apalutamide, sold under the brand name Erleada among others, is a nonsteroidal antiandrogen (NSAA) medication which is used in the treatment of prostate cancer. It is specifically indicated for use in conjunction with castration in the treatment of non-metastatic castration-resistant prostate cancer (NM-CRPC). It is taken by mouth.

<span class="mw-page-title-main">Proxalutamide</span> Chemical compound

Proxalutamide 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 COVID-19, prostate cancer, and breast cancer. It was approved in Paraguay for the treatment of COVID-19 in July 2021, but has not been approved at this time in other countries.

Ketodarolutamide is a nonsteroidal antiandrogen (NSAA) and the major active metabolite of darolutamide, an NSAA which is used in the treatment of prostate cancer in men. Similarly to its parent compound, ketodarolutamide acts as a highly selective, high-affinity, competitive silent antagonist of the androgen receptor (AR). Both agents show much higher affinity and more potent inhibition of the AR relative to the other NSAAs enzalutamide and apalutamide, although they also possess much shorter and comparatively less favorable elimination half-lives. They have also been found not to activate certain mutant AR variants that enzalutamide and apalutamide do activate. Both darolutamide and ketodarolutamide show limited central nervous system distribution, indicating peripheral selectivity, and little or no inhibition or induction of cytochrome P450 enzymes such as CYP3A4, unlike enzalutamide and apalutamide.

Ralaniten is an N-terminal domain antiandrogen which was never marketed. It is a derivative of bisphenol A and one of the four stereoisomers of EPI-001. A prodrug of ralaniten, ralaniten acetate (EPI-506), was under development for the treatment of prostate cancer.

Dimethylcurcumin is a nonsteroidal antiandrogen and a synthetic curcuminoid which is under development by AndroScience Corporation as a topical medication for the treatment of acne vulgaris. It has also been under investigation for the treatment of male pattern hair loss, spinal muscular atrophy, and wounds, but no development has been reported for these indications. There has been interest in the drug for the potential treatment of prostate cancer as well. As of 2017, it is in phase II clinical trials for acne vulgaris.

<span class="mw-page-title-main">BMS-641988</span> Chemical compound

BMS-641988 is a nonsteroidal antiandrogen which was developed by Bristol-Myers Squibb for the treatment of prostate cancer but was never marketed. It acts as a potent competitive antagonist of the androgen receptor (AR) (Ki = 10 nM; IC50 = 56 nM). The drug was found to have 20-fold higher affinity for the AR than bicalutamide in MDA-MB-453 cells, and showed 3- to 7-fold the antiandrogenic activity of bicalutamide in vitro. It may have some weak partial agonist activity at the androgen receptor. BMS-641988 is transformed by CYP3A4 into BMS-570511, and this metabolite is then reduced to BMS-501949 by cytosolic reductases. All three compounds show similar antiandrogenic activity. In addition to its antiandrogenic activity, BMS-641988 shows activity as a negative allosteric modulator of the GABAA receptor, and can produce seizures in animals at sufficiently high doses. It also shows some drug-induced QT prolongation. BMS-641988 reached phase I clinical trials prior to the discontinuation of its development. The clinical development of BMS-641988 was terminated due to the occurrence of a seizure in a patient during a phase I study.

<span class="mw-page-title-main">EM-5854</span> Chemical compound

EM-5854 is a steroidal antiandrogen which was under development by Endoceutics, Inc. for the treatment of prostate cancer. It was first described in a patent in 2008, and was further characterized in 2012. EM-5854 reached phase I/II clinical trials for the treatment of prostate cancer but development was discontinued in March 2019.

EPI-7386 is an N-terminal domain antiandrogen, or antagonist of the N-terminal domain (NTD) of the androgen receptor (AR), which is under development for the treatment of prostate cancer. 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). EPI-7386 shows 20-fold higher antiandrogenic potency than ralaniten in vitro (IC50 = 535 nM vs. 9,580 nM, respectively), as well as greater stability in human hepatocytes. It is planned to enter phase I clinical trials in 2020.

<span class="mw-page-title-main">Rezvilutamide</span> Chemical compound

Rezvilutamide (INN), sold under the brand name Ariane, is a nonsteroidal antiandrogen which is approved for the treatment of prostate cancer in China and is or was under development for the treatment of breast cancer. It is a selective androgen receptor antagonist with reduced brain distribution compared to the structurally related nonsteroidal antiandrogen enzalutamide. The drug was developed by Jiangsu Hengrui Medicine. Other structural analogues of rezvilutamide that are also used as antiandrogens besides enzalutamide include apalutamide and proxalutamide.

References

  1. 1 2 "Ralaniten acetate - ESSA Pharma". AdisInsight. Springer Nature Switzerland AG.
  2. Martinez-Ariza G, Hulme C (2015). "Recent advances in allosteric androgen receptor inhibitors for the potential treatment of castration-resistant prostate cancer". Pharmaceutical Patent Analyst. 4 (5): 387–402. doi:10.4155/ppa.15.20. PMID   26389532.
  3. "A phase 1/2 open-label study of safety and antitumor activity of EPI-506, a novel AR N-terminal domain inhibitor, in men with metastatic castration-resistant prostate cancer (mCRPC) with progression after enzalutamide or abiraterone". Journal of Clinical Oncology. ISSN   0732-183X. Archived from the original on 2016-03-06. Retrieved 2016-02-27.
  4. Silberstein JL, Taylor MN, Antonarakis ES (April 2016). "Novel Insights into Molecular Indicators of Response and Resistance to Modern Androgen-Axis Therapies in Prostate Cancer". Current Urology Reports. 17 (4): 29. doi:10.1007/s11934-016-0584-4. PMC   4888068 . PMID   26902623.
  5. Monaghan AE, McEwan IJ (2016). "A sting in the tail: the N-terminal domain of the androgen receptor as a drug target". Asian Journal of Andrology. 18 (5): 687–94. doi: 10.4103/1008-682X.181081 . PMC   5000789 . PMID   27212126.
  6. Myung JK, Banuelos CA, Fernandez JG, Mawji NR, Wang J, Tien AH, et al. (July 2013). "An androgen receptor N-terminal domain antagonist for treating prostate cancer". The Journal of Clinical Investigation. 123 (7): 2948–60. doi:10.1172/JCI66398. PMC   3696543 . PMID   23722902.
  7. "ESSA Pharma Announces Results from the Phase 1 Clinical Trial of EPI-506 for Treatment of mCRPC and Updates Clinical and Strategic Plans" (Press release). ESSA Pharma.