Chemistry:Deuterated testosterone

Deuterated testosterone

Clinical data
Other names	AVA-291; AVA291; d-Testosterone; d3-Testosterone; d3-T; Deutestosterone; Testosterone-19-d3; 17β-Hydroxyandrost-4-en-3-one-19,19,19-D3
Routes of administration	Oral, transdermal, parenteral
Drug class	Androgen; Anabolic steroid
Identifiers
IUPAC name (8R,9S,10R,13S,14S,17S)-17-hydroxy-13-methyl-10-(trideuteriomethyl)-1,2,6,7,8,9,11,12,14,15,16,17-dodecahydrocyclopenta[a]phenanthren-3-one
CAS Number	69660-28-2
PubChem CID	56619059
ChemSpider	129395050
UNII	6BBK8AP9G8
Chemical and physical data
Formula	C19H28O2
Molar mass	288.431 g·mol−1
3D model (JSmol)	Interactive image
SMILES [2H]C([2H])([2H])[C@]12CCC(=O)C=C1CC[C@@H]3[C@@H]2CC[C@]4([C@H]3CC[C@@H]4O)C
InChI InChI=1S/C19H28O2/c1-18-9-7-13(20)11-12(18)3-4-14-15-5-6-17(21)19(15,2)10-8-16(14)18/h11,14-17,21H,3-10H2,1-2H3/t14-,15-,16-,17-,18-,19-/m0/s1/i1D3 Key:MUMGGOZAMZWBJJ-RJSKNYPQSA-N

Deuterated testosterone (developmental code name AVA-291), also known as d3-testosterone (d3-T), is an androgen or androgen receptor agonist which is under development for the treatment of breast cancer, female sexual dysfunction, hypogonadism, decreased libido, fatigue, and muscular atrophy. It is taken orally, transdermally, or parenterally.

The drug is an isotopologue of testosterone. More specifically, the three hydrogen atoms on the C19 methyl group have been replaced with the deuterium isotopes. Unlike testosterone, deuterated testosterone is highly resistant to metabolism into estradiol by aromatase, showing a half-life that is 4 to 7 times longer than that of testosterone in an aromatase-containing system in vitro (55.9–79.9 minutes vs. 7.7–18.5 minutes, respectively). On the other hand, they were metabolized at similar rates in rat and human hepatocytes. In addition, deuterated testosterone had similar potency and efficacy as testosterone as an androgen receptor agonist in vitro. As such, deuterated testosterone is expected to retain activity as an androgen similarly to testosterone but to lack or have greatly reduced estrogenic activity. Accordingly, deuterated testosterone showed 1,000-fold lower potential in stimulating breast cancer cell proliferation compared to testosterone.

The chemical synthesis of deuterated testosterone has been described.

Deuterated testosterone was first described in the scientific literature by 1978. It is under development by Lennham Pharmaceuticals and Aviva Biopharm. As of December 2025, the drug is in the preclinical research stage of development. A phase 1 trial is being planned for early 2026. Deuterated testosterone was patented in 2021. It is expected to have improved tolerability and safety relative to testosterone in certain contexts, for instance avoiding gynecomastia (male breast development) or treating estrogen-sensitive breast cancer.

See also

• List of investigational sex-hormonal agents
• List of investigational sexual dysfunction drugs

External links

• d-Testosterone - Pipeline - Lennham Pharmaceuticals
• The Science / Our Innovation (Meet d3-Testosterone: A Molecular Reinvention) - Aviva Bio
• Lennham Pharmaceuticals Announces Discovery of Next Generation Testosterone Candidate - Lennham Pharmaceuticals

{{Navbox

| name = Androgens and antiandrogens
| title = Androgens and antiandrogens
| state = collapsed
| listclass = hlist
| groupstyle = text-align:center;

| group1 = Androgens
(incl. AAS)

| list1 =

AR agonists

Testosterone derivatives: Androstenediol dipropionate Boldenone undecylenate Clostebol Clostebol acetate Clostebol caproate Clostebol propionate Cloxotestosterone acetate Prasterone (dehydroepiandrosterone, DHEA) Prasterone enanthate (DHEA enanthate) Prasterone sulfate (DHEA sulfate) Quinbolone Testosterone# Testosterone esters (e.g., testosterone cypionate, testosterone enanthate]], testosterone propionate]], testosterone undecanoate]], testosterone ester mixture]]s (Deposterona, Omnadren, Sustanon, Testoviron Depot)) Dihydrotestosterone derivatives: Androstanolone (stanolone, dihydrotestosterone, DHT) Androstanolone esters Bolazine capronate Drostanolone propionate (dromostanolone propionate) Epitiostanol Mepitiostane Mesterolone Metenolone acetate (methenolone acetate) Metenolone enanthate (methenolone enanthate) Stenbolone acetate 19-Nortestosterone derivatives: Bolandiol dipropionate Nandrolone esters (e.g., nandrolone decanoate, nandrolone phenylpropionate) Norclostebol Norclostebol acetate Oxabolone cipionate (oxabolone cypionate) Trenbolone acetate Trenbolone hexahydrobenzylcarbonate (trenbolone cyclohexylmethylcarbonate) 17α-Alkylated testosterone derivatives: Bolasterone Calusterone Chlorodehydromethyltestosterone (CDMT) Fluoxymesterone Formebolone Metandienone (methandienone, methandrostenolone) Methandriol (methylandrostenediol) Methandriol bisenanthoyl acetate Methandriol dipropionate Methandriol propionate Methyltestosterone Methyltestosterone 3-hexyl ether Oxymesterone Penmesterol Tiomesterone (thiomesterone) 17α-Alkylated dihydrotestosterone derivatives: Androisoxazole Furazabol Mebolazine (dimethazine) Mestanolone Oxandrolone Oxymetholone Stanozolol 17α-Alkylated 19-nortestosterone derivatives: Ethylestrenol Mibolerone Norethandrolone Normethandrone (methylestrenolone, normethisterone) Propetandrol (propethandrol) 17α-Vinyltestosterone derivatives: Norvinisterone (vinylnortestosterone) 17α-Ethynyltestosterone derivatives: Danazol Gestrinone Progestins (e.g., ethisterone (ethynyltestosterone), levonorgestrel, norgestrel, norethisterone (norethindrone), [[Chemistry:Lynestrlynestrenol, Norgestrienone|norgestrienone]]) Tibolone Progesterone derivatives: Medroxyprogesterone acetate

Progonadotropins

Antiestrogens (e.g., tamoxifen, Chemistry:Clomifene

| group2 = Antiandrogens
| list2 = {{Navbox|child
| groupstyle = text-align:center;
| groupwidth = 9em;

  | group1 = AR antagonists
  | list1 =

• Steroidal: Abiraterone acetate
• Canrenone
• Chlormadinone acetate
• Cyproterone acetate
• Delmadinone acetate
• Dienogest
• Drospirenone
• Medrogestone
• Megestrol acetate
• Nomegestrol acetate
• Osaterone acetate
• Oxendolone
• Potassium canrenoate
• Spironolactone

• Nonsteroidal: Apalutamide
• Bicalutamide
• Cimetidine
• Darolutamide
• Enzalutamide
• Flutamide
• Ketoconazole
• Nilutamide
• Seviteronel^†
• Topilutamide (fluridil)

  | group2 = Steroidogenesis
inhibitors

| list2 =

5α-Reductase	Alfatradiol Dutasteride Epristeride Finasteride Saw palmetto extract
Others	Abiraterone acetate Aminoglutethimide Bifluranol Cyproterone acetate Flutamide Ketoconazole Nilutamide Seviteronel† Spironolactone

  | group3 = Antigonadotropins
  | list3 =

• D₂ receptor antagonists (prolactin releasers) (e.g., domperidone, metoclopramide, risperidone, haloperidol, chlorpromazine, sulpiride)
• Estrogens (e.g., bifluranol, [[diethylstilbestrol, estradiol, estradiol esters, ethinylestradiol, ethinylestradiol sulfonate, paroxypropione)
• GnRH agonists (e.g., leuprorelin)
• GnRH antagonists (e.g., cetrorelix)
• Progestogens (incl., chlormadinone acetate, [[cyproterone acetate, hydroxyprogesterone caproate, gestonorone caproate, [[Chemistry:Medroxyprogesterone medroxyprogesterone acetate, Chemistry:Megestrol acetate|megestrol acetate]])

  | group4 = Others
  | list4 =

• Androstenedione immunogens: Androvax (androstenedione albumin)
• Ovandrotone albumin (Fecundin)

}}

| liststyle = background:#DDDDFF;

| list3 =

• ^#WHO-EM
• ^‡Withdrawn from market
• Clinical trials:
  • ^†Phase III
  • ^§Never to phase III

See also

Androgen receptor modulators

Estrogens and antiestrogens

Progestogens and antiprogestogens

List of androgens/anabolic steroids

}}