An ovarian cancer drug, which targets the alpha folate receptor (FRα), is set to enter Phase II trials.
Idetrexed (formerly known as BTG945, ONX-0901 and CT900) was created by scientific teams in what is now The Institute of Cancer Research (ICR) Centre for Cancer Drug Discovery, London, UK.
The drug has already shown particular promise in ovarian cancer in a first-in-human, Phase I trial led by researchers at the ICR and The Royal Marsden NHS Foundation Trust.
The Phase II trial is part of a new agreement between US-based pharmaceutical company Algok Bio and BTG International, which partnered with the ICR earlier in the drug’s development. Cancer Research UK also helped to fund earlier research.
Algok Bio’s exclusive license agreement with BTG grants the former the rights to develop and commercialise idetrexed worldwide. Algok Bio will soon initiate pivotal studies for registering idetrexed for ovarian cancer treatment. Additional clinical programmes exploring other indications and combination regimens with standard care will also be pursued.
Comparable efficacy to antibody drug conjugates
Idetrexed is a potent thymidylate synthase inhibitor that triggers cell death while selectively targeting the alpha folate receptor (FRα), which is highly expressed in cancer cells compared to normal tissues across a variety of solid tumours.
Over 90% of ovarian cancer cases express FRα, with high levels of overexpression also observed in endometrial, triple-negative breast cancer, and mesothelioma. Kidney, lung, colorectal, and gastric cancers also exhibit varying degrees of expression.
Professor Udai Banerji, Principal Investigator of the idetrexed Phase I study and Co-Director of Drug Development at the ICR and The Royal Marsden, said: “Idetrexed is a small molecule targeting FRα-overexpressing cancers that has shown significant single agent activity in Phase I clinical trials. In a similar stage of development, idetrexed has shown comparable efficacy to drugs such as antibody drug conjugates that have gone on to successful late phase development.”
