In short
KD033 is an investigational immunotherapy that combines an anti-PD-L1 antibody with interleukin-15 (IL-15). It is being studied in people with metastatic or locally advanced solid tumors. One completed Phase 1 trial (NCT04242147) enrolled 80 participants to evaluate safety, tolerability, and early signs of efficacy.
Key points
- KD033 is a clinical-stage immunocytokine made of an anti-PD-L1 antibody linked to IL-15.
- The only registered clinical trial is a Phase 1 study in metastatic or locally advanced solid tumors.
- The trial enrolled 80 participants and has been completed.
- Researchers tested bi-weekly and weekly intravenous dosing to find the maximum tolerated dose.
- The main goal was to measure dose-limiting toxicities and treatment-related side effects.
- Preclinical work showed the molecule can target IL-15 to PD-L1-expressing cells in a mouse model.
What is KD033?
KD033 is an investigational immunotherapy, meaning it has not been approved as a medicine. It is a clinical-stage immunocytokine: a laboratory-made molecule that joins an antibody to a signalling protein called a cytokine. The antibody part targets PD-L1, a protein found on many cancer cells and some immune cells. The cytokine part is human interleukin-15 (IL-15), a protein that can stimulate immune cells. The molecule is also known by the development code SAR445710.
How does KD033 work?
KD033 is designed to bring IL-15 directly to cells that carry PD-L1. PD-L1 is a checkpoint protein that can help tumours avoid attack by the immune system. The anti-PD-L1 antibody part of KD033 binds to PD-L1, while the IL-15 part is intended to activate immune cells such as T cells and natural killer cells. In a mouse model engineered to express human PD-1 and PD-L1, researchers showed that KD033 could deliver IL-15 to PD-L1-expressing cells in the body. This dual action is meant to focus immune stimulation on the tumour area rather than the whole body.
Which conditions is KD033 being studied for?
The registered clinical trial for KD033 included people with the following condition:
- Metastatic or locally advanced solid tumours — cancers that have spread to other parts of the body or grown into nearby tissues and cannot be removed by surgery alone.
How is KD033 given?
In the clinical trial, KD033 was given by intravenous infusion, which means it was delivered directly into a vein. The trial tested two dosing schedules: once every two weeks (bi-weekly) and once every week (weekly). The dose used in the reported intervention was 400 micrograms per kilogram of body weight.
What do the clinical trials show?
One Phase 1 trial of KD033 is registered in public records. The study, identified as NCT04242147, was completed after enrolling 80 participants with metastatic or locally advanced solid tumours. Phase 1 trials are the earliest stage of testing in humans. Their main purpose is to find out whether a treatment is safe, what doses can be tolerated, and how the body handles the drug.
The trial had two parts. The dose escalation part tested bi-weekly and weekly monotherapy dosing to determine safety, tolerability, and the maximum tolerated dose (MTD). The expansion part aimed to confirm safety and tolerability and look for early signals of efficacy.
The primary outcomes measured were dose-limiting toxicities (DLTs) — side effects severe enough to prevent giving a higher dose — during dose escalation, and treatment-emergent adverse events (TEAEs) and treatment-related adverse events by severity across all dose groups. Side effects were graded using the National Cancer Institute Common Terminology Criteria for Adverse Events Version 5.0 (NCI CTCAE v5.0).
What side effects are known?
The public registry record for the Phase 1 trial does not report results on specific side effects. The trial measured dose-limiting toxicities and treatment-emergent adverse events, but the outcomes themselves have not been published in the registry. The preclinical source does not describe side effects in humans. Therefore, no specific side effect profile for KD033 can be reported here.