Argireline (Acetyl hexapeptide-3) is composed of chains of amino acids known as peptides. Argireline significantly inhibits Ca2+ dependent neurotransmitter release (acetylcholine) at the neuromuscular junction.

Selective, high affinity, non-competitive α1A adrenoceptor antagonist (Ki = 0.35 nM). Exhibits no significant activity against a range of other GPCRs, including α2A, β1 and β2 adrenoceptors. Antagonizes effects of phenylephrine on isolated rabbit prostate muscle in vitro and on intra-urethral pressure in rats.

Mc-Val-Cit-PAB-Cl can be used to conjugate MMAE and antibody to form antibody-MC-vc-MMAE.