Draft:Anitens

• Comment: This reads like a wiktionary entry Sulfurboy (talk) 03:19, 8 September 2026 (UTC)

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Anitens

Definition

Anitens are a new pharmacological class recognized by United States Adopted Names (USAN) Council.  They are defined as a drug designed to bind to the androgen receptor N-terminal domain such as ralaniten. and masofaniten.

Mechanism and Clinical Trials

• Anitens were discovered by Dr. Marianne D Sadar and Dr. Raymond J Andersen for the treatment of pathologies driven by androgen receptor such as prostate cancer .
• EPI-001 (racemic mixture containing ralaniten/EPI-002) was the first mixture of anitens discovered.
• The mechanism of EPI-001 and other anitens involves: 1) binding to the N-terminal domain within the activation function-1 region of the androgen receptor; 2) inhibition of interactions of androgen receptor with coregulatory proteins; 3) blocking androgen receptor interaction with androgen-response elements on target genes; 4) prevention of androgen-induced proliferation; and 5) cytoreduction of castration-resistant prostate cancer xenografts that were dependent on androgen receptor for growth and survival without causing toxicity.
• Iodo-ralaniten (¹²³I-EPI-002) was proposed as an imaging agent to reveal tumors expressing full-length androgen receptor and truncated constitutively active splice variants.
• Ralaniten/ralaniten triacetate (EPI-506) and masofaniten were the first discovered small molecules to reach clinical trials NCT02606123; NCT04421222; NCT05075577; NCT05295927) that directly bind to the intrinsically disordered transactivation domain of the androgen receptor, which was previously considered ‘undruggable’.
• Ralaniten-triacetate (EPI-506) was the first drug that binds to any intrinsically disordered protein to enter first-in-human clinical trials NCT02606123;
• Masofaniten [18] entered Phase1/2 clinical trials for the treatment of prostate cancer (NCT04421222; NCT05075577; NCT05295927)).
• Together these clinical trials with anitens provided proof-of-concept of activity in some patients as well as the safety and tolerability of the drug scaffold.
• Anitens provided the first evidence that small molecules that bind intrinsically disordered transactivation domains may tune their transcriptome
• Some anitens have binding coefficients in the picomolar or low nanomolar range, marking a major advance in drug discovery against intrinsically disordered proteins that were previously considered undruggable.