ADC Assets

Why choose Biocytogen's BsADC assets?

Targeting two tumor-associated antigens with a bispecific ADC (bsADC) is a therapeutic strategy to reduce off-tumor toxicity and improve antitumor efficacy. To enable discovery of novel bsADCs for this purpose, our team developed a large-scale bsADC platform with these key advantages:

• Fully Human, Common Light Chain Antibodies: Our RenLite mice produce genetically diverse, fully human common light chain antibody backbones, which can be assembled into Y-shaped bispecific antibodies to facilitate the CMC process.
• Novel Linker/Payload: Use of a proprietary linker/payload system, BLD1102, which is composed of a super hydrophilic and cleavable linker, and a novel topoisomerase I inhibitor payload BCPT02 with high potency and strong bystander killing effect. It also demonstrated a favorable safety profile in cynomolgus monkey.

Our BsADC projects

Our TAA antibody library

Selected assets overview

Biocytogen has reached some agreements with ADC companies around the world, including IDEAYA, ABL Bio, Ona Therapeutics and ADC Therapeutics. Contact us today to explore evaluation, licensing, or co-development opportunities!

PTK7 x EGFR bsADC

BCG017 Highlights

• PTK7 and EGFR co-expressed in various solid tumors
• BCG017 exhibited a synergistic effect and effectively addressed tumor heterogeneity
• By leveraging moderate-affinity EGFR arm, the approach demonstrated reduced internalization and potency when interacting with EGFR alone, potentially reducing EGFR-driven toxicity in normal tissues
• Excellent plasma stability (<0.5% free payload after 21 days of incubation, less than Enhertu)

Superior efficacy in various PDX models

PDX	cancer type	PTK7 H score	EGFR H score	bsADC vs bencchmark ADCs
BP1395	breast	61	241	superior
BP0595	breast	107	188	superior
BP0847	CRC	29	215	superior
BP1013	gastric	124	96	superior
BP0634	gastric	ultra low	84	comparable
BP0554	NSLCL	6	265	superior
BP0865	esophagus	73	269	comparable
BP0203	pancreatic	27	266	comparable

Co-expression of PTK7 x EGFR in multiple cancer cell types

Strongest binding when both targets are expressed

PTK7 x TROP2 BsADC (BCG033)

Highlights of our assets:

• The clinical efficacy of TRODELVY is limited by the toxicity of this single-target agent. To improve the therapeutic window and increase the efficacy, we sought to develop a TROP2-related bsADC for metastatic TNBC.
• PTK7 is highly expressed in breast cancer, especially in TNBC. PTK7 also is enriched in tumor-initiating cells.
• BCG033 is a novel anti-PTK7 x TROP2 bsADC, which exhibited superior anti-tumor efficacy to the benchmark ADCs in vivo.

Co-expression of PTK7 x TROP2 in multiple cancer cell types

Superior anti-tumor efficacy to benchmark ADCs in xenograft models