ECYT has applied for approval in Europe last November. The filed with data from a phase IIb trial, this is called the PRECEDENT trial, for ovarian cancer. Vintafolide is compared against current standard of care, which is called PLD (pegylated liposomal doxorubicin). At the time of the readout, patients that were 100% folate positive (more on that in a minute) had a PFS of 24 weeks compared to 6.6 weeks in the PLD treated patients. PFS is a surrogate end point called progression free disease. The real end point is remission and/or survival, and the data is still being collected as long as the patients continue on this trial. ECYT also has a diagnostic agent that can tell them which patients have folate positive cancer or not, those that are folate+ will have a much more favorable response to Vintafolide.
A phase III trial is currently underway, which essentially is a repeat of the trial described above. This on is called PROCEED. Data from that trial will be used to seek FDA approval in the US. I am not clear on the strategy of why ECYT did not file with the FDA with the same phase IIb data they used for the EU filing.