Sonnet announces ADC platform available for drug discovery partnerships

Sonnet BioTherapeutics (SONN) Holdings announced its plans to advance the development of its proprietary Antibody Drug Conjugate (ADC) platform which was designed to circumvent many of the technical challenges associated with ADCs. Additionally, the Company announced the release of a Virtual Investor “What This Means” segment to discuss plans for its ADC platform. The initial proof-of-concept construct was designated as SON-5010, which is produced through a two-step process whereby the targeting scaffold and payload domains are either expressed and purified from mammalian cells or chemically synthesized, respectively, and then joined to create the final ADC conjugate using a chemical linkage process. The SON-5010 ADC construct is comprised of an anti-HER2-FHAB-anti-HER2 targeting scaffold linked to a docking peptide that has 3 equally spaced lysine residues which serve as conjugation sites for monomethyl auristatin E, a synthetic antineoplastic agent that disrupts the microtubule network and suppresses cell proliferation and mitosis, including G2/M arrest. This initial SON-5010 ADC was used in a head-to-head comparison with an approved product, Kadcyla, which has a very similar anti-HER2 targeting domain and linker chemistry but is conjugated with a different toxin payload known as mertansine and a trastuzumab-MMAE complex, consisting of a humanized anti-HER2 receptor monoclonal antibody with the same linker chemistry and 3x MMAE DAR payload as SON-5010.