A non-invasive method for measuring the expression folate receptors on tumour cells can identify which patients with advanced lung cancer are likely to derive greater benefit from combination chemotherapy with the investigational drug vintafolide, researchers report at ESMO 2014.

At the meeting, medical oncologist Dr Rohit Lal from Guy’s & St Thomas’ NHS Foundation Trust in London, reported results from the phase II TARGET trial, which included 199 patients with non-small cell lung cancer who had already been treated with other drugs, and whose tumours all expressed the folate receptor.

Folic acid and folates are key to the synthesis of DNA and RNA, and abnormalities in folate pathways and folate receptors are involved in many cancers including lung cancer, Lal explains.

Vintafolide is a drug targeted to the folate receptor, and is being developed together with an imaging agent that enables non-invasive imaging of folate receptor expression in tumours.

“Our results show a statistical improvement in overall survival and a promising progression-free survival signal with vintafolide and docetaxel for advanced lung adenocarcinoma patients selected by an imaging biomarker for the folate receptor. These patients also had a higher rate of radiological disease control. More patients treated in the vintafolide combination arm required dose adjustment. The results warrant confirmation in a phase III study,” Lal said.

"In this phase II trial, adenocarcinoma patients treated with the vintafolide combination were half as likely to have succumbed from their disease than patients in the docetaxel group. These results will need to be validated in a phase III trial," Lal said.

“Choosing treatments based on tumour biopsy tests is well established. The TARGET trial results show a positive outcome for 2nd-line advanced lung adenocarcinoma patients and may show that by using a scan we can select advanced stage lung cancer patients that may derive a greater benefit from combination chemotherapy.”

“This group reports the results of a revolutionary study employing a non-invasive method to detect folate receptor expression in NSCLC cells and the relation to treatment with vintafolide, targeting the folate receptor,” Rosell noted.

“The preliminary results are promising, indicating that the combination of vintafolide and docetaxel could be effective in advanced lung adenocarcinoma patients selected by imaging tracer for the folate receptor.”

Source: ESMO