pTag9aa peptide tag (pTag9aa)

pTag9aa is a synthetic 9-amino acid peptide tag developed by Strike Pharma as a core component of their Adaptable Drug Affinity Conjugate (ADAC) technology [2]. It serves as a high-affinity docking site for a specialized single-chain variable fragment (scFv) that is recombinantly fused to a therapeutic antibody, such as an agonistic anti-CD40 antibody [1, 4]. This system allows for the rapid, non-covalent, and modular attachment of various peptide antigens, such as tumor neoantigens, to the antibody carrier [2, 5]. The primary biological function of the pTag9aa system is to facilitate the targeted delivery of these antigens to antigen-presenting cells (APCs) to stimulate a robust immune response [1, 3]. By co-delivering immune-stimulating signals and specific antigens, the pTag9aa-based platform aims to improve the efficacy of personalized cancer immunotherapies [2, 8]. The tag was optimized through the trimming of an 18-amino acid precursor to minimize potential immunogenicity while maintaining picomolar binding affinity (approximately 9.4 pM) [2, 3]. In preclinical studies, drugs utilizing this tag, such as STRIKE2001, have shown significant anti-tumor activity and a favorable safety profile compared to traditional systemic agonists [4, 6].

Other names

pTag9aa pTagTrimmed pTagADAC peptide tag

High-affinity non-covalent binding to a specific scFv to facilitate modular cargo delivery