SynTum™ is Phrontline Bio's proprietary platform for Dual-Linker Payload ADCs (DLP-ADCs) — a new architecture designed to deliver two payloads with distinct mechanisms of action in a single molecule.

Each DLP-ADC is engineered for selective payload release within the tumor microenvironment (TME), whether through cleavage of its dual linkers by tumor-associated enzymes or local pH, or through target-mediated internalization and release of conjugated payloads. This precisely localized release allows both payloads to act in concert, producing synergistic tumor cell killing beyond what either mechanism could achieve alone.

Phrontline Bio has built a versatile toolkit of four distinct linker-payload modalities — spanning topoisomerase inhibitors, microtubule inhibitors, DNA alkylators, and PTM enzyme inhibitors — enabling tailored payload combinations across diverse tumor biology.

Combination chemotherapy works because tumors rarely escape two mechanisms at once. SynTum™ brings that principle to antibody‒drug conjugates.

Two targets. Our bispecific and biparatopic antibodies are tuned for each target’s affinity, so they bind tumors that co-express both antigens, internalize faster, and stay active where expression of either antigen alone is low or heterogeneous.

Two payloads, one linker. Our proprietary DLP™ linkers are pre-assembled, branched constructs that carry two payloads with distinct mechanisms of action. Because both payloads sit on the same linker, they are attached to the antibody in a single conjugation step, giving a fixed payload ratio and a well-defined,

homogeneous product [confirm: DAR per payload], with simpler CMC than sequential dual conjugation.

A modular toolkit. Four linker-payload classes (topoisomerase I inhibitors, microtubule inhibitors, DNA alkylators and PTM-enzyme inhibitors), plus targeted small-molecule payloads , let us match the payload pair to the tumor biology.

Clinically tested. TJ102, the first SynTum™ bispecific dual-payload ADC, entered a global Phase I/II trial in September 2026