CBT-501 (genolimzumab) is an immunotherapy that CBT Pharmaceutical is developing to combat solid tumors.

It is called a PD-1 inhibitor because it targets a protein called programmed cell death 1, or PD-1, on the surface of immune cells.

How CBT-501 works

Many cancers have an ability to escape immune system detection.

Immunotherapies are a new type of treatment. They work not by attacking cancer cells directly but by teaching the immune system to recognize and kill the cells.

PD-1 helps shield tumors from the immune system. Blocking it eliminates the shield, allowing the immune system to destroy the cancer.

CBT-501 in clinical trials

CBT Pharmaceuticals’ preclinical-trial studies showed that CBT-501 was as effective as two approved PD-1 inhibitors, Bristol-Myers Squibb’s Opdivo (nivolumab) and Merck’s Keytruda (pembrolizumab), against solid tumors. The study also showed it to be safe and to generate low toxicity.

CBT-501 ‘s clinical trial program is in its early stages.

A Phase 1 trial (NCT03053466), which started in March 2017, continues to recruit people with solid tumors in Australia. Its main objectives are to determine CBT-501’s safety, patients’ ability to tolerate it, and a recommended dose for a Phase 2 trial.

Patients in the Phase 1 trial have advanced-stage solid tumors that have stopped responding to other  therapies.

Researchers hope to recruit 50 people for the trial. They can have a variety of cancers, including either colorectal, endometrial, gastric, head and neck, liver, lung, mesothelioma, ovarian, or kidney tumors.


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