Technetium (99mTc) etarfolatide is an investigational non-invasive, folate receptor-targeting companion imaging agent that is being developed by Endocyte.

[1] Etarfolatide consists of a small molecule targeting the folate receptor and an imaging agent, which is based on technetium-99m.

[2] Etarfolatide is currently being investigated together with the corresponding small molecule drug conjugate (SMDC) vintafolide in a Phase 3 study in platinum-resistant ovarian cancer and in a Phase 2b study in non-small cell lung cancer.

It identifies patients with metastases that are positive for the folate receptor and therefore more likely to respond to treatment with vintafolide.

[3][4] The European Medicines Agency (EMA) is reviewing the Marketing Authorization Application (MAA) filings for both vintafolide and etarfolatide, for the treatment of patients with folate receptor-positive platinum-resistant ovarian cancer in combination with pegylated liposomal doxorubicin (PLD).