- Hepatocytes may be subject to on-target toxicity for DR5 pathway agonism.
- Previous tetravalent DR5 agonists failed in the clinic due to hepatotoxicity—likely due to hyper-clustering by anti-drug antibodies.
- In vitro hepatic cell (HepaRG) death assay recapitulates toxicity of TAS266 + pre-existing anti-drug antibodies (PE-ADAs) in pooled human immunoglobulins.
- Proper valency is key: Hexavalent (Hex-1F5) is also hepatotoxic.
![Inbrx 109 Graphic](https://inhibrx.com/wp-content/uploads/2020/08/inbrx-109-graphic.jpg)
The Candidate
Our tetravalent DR5 agonist.
INBRX-109, our tetravalent DR5 agonistic antibody, is designed to exploit tumor-biased direct cell death induction by DR5 activation in numerous cancer types.
With a valency of four, it has the ability to potently agonize DR5 through efficient receptor clustering, causing cell death, but by way of our sdAb platform, also eliminates recognition by pre-existing anti-drug antibodies (ADAs) to lessen the potential for hyper-clustering.
Valency Drives DR5-Mediated Apoptosis
Apoptosis is the death of cells that occurs as a normal and controlled part of an organism’s growth or development. DR5 requires the proper valency to trigger apoptosis of cancer cells—and spare healthy cells.
![Inbrx 109 Graphic](https://inhibrx.com/wp-content/uploads/2020/08/inbrx-109-graphic.png)
Engineered to Avoid Hepatotoxicity
Human Hepatocyte Toxicity Assay
![Inbrx 109 Chart](https://inhibrx.com/wp-content/uploads/2020/08/inbrx-109-chart.jpg)
![Inhibrx Block 01](https://inhibrx.com/wp-content/uploads/2020/08/inhibrx-block-01.jpg)
INBRX-109 Clinical Trial
The Phase 1 trial for INBRX-109 is currently enrolling combination treatment cohorts in Ewing sarcoma and SDH-deficient gastrointestinal stromal tumor (GIST).
The registration-enabling Phase 2 trial for INBRX-109 is currently enrolling patients with unresectable or metastatic conventional chondrosarcoma.
Phase 1 Trial Phase 2 Trial