AVEO Pharmaceuticals, Inc. (NASDAQ:AVEO) announced that it has received written feedback from the U.S. Food and Drug Administration regarding a potential pivotal study for tivozanib in the treatment of NRP-1 low colorectal cancer (CRC). Tivozanib is an oral, potent, selective inhibitor of vascular endothelial growth factor (VEGF) with a long half-life and activity against all three VEGF receptors.

AVEO recently presented results from the BATON-CRC study, a 265 patient randomized trial exploring the combination of mFOLFOX6 and tivozanib or bevacizumab as first-line treatment in patients with advanced metastatic CRC, at the 2015 American Association for Cancer Research (AACR) Tumor Angiogenesis and Vascular Normalization Conference. Among the predefined biomarkers explored in this study, neuropilin-1 (NRP-1), a signaling protein known to bind to VEGF-A in serum, was found to be a potential prognostic marker for angiogenesis inhibitor activity and may be predictive of tivozanib activity relative to bevacizumab.

Results from this study and the Company’s ongoing assay development efforts were presented to the FDA. Updated analyses from the Company’s assay development efforts, which are similar to those presented at the AACR conference, will be presented at the upcoming European Society of Medical Oncology 17th World Congress on Gastrointestinal Cancer taking place July 1-4, 2015 in Barcelona Spain.

In response to questions from AVEO regarding a proposed pivotal phase 3 trial of tivozanib in CRC, the FDA suggested that the Company continue work on the development of its biomarker assay to address variability between assays presented, and that, at present, “insufficient data exists to determine the appropriateness of this [NRP-1 low] subgroup” for the proposed phase 3 study. This feedback is consistent with the Company’s current clinical strategy and discussions with cancer research cooperative groups. As such, AVEO plans to evaluate options to confirm the activity of tivozanib and FOLFOX in NRP-1 low CRC through a prospectively defined, randomized Phase 2 study, while continuing to work on the development of a commercially viable assay.

“NRP-1 expression is a biomarker of growing interest for malignancies treated with angiogenesis inhibitors,” said Michael Bailey, president and chief executive officer of AVEO. “As part of our effort to develop a commercial companion diagnostic, we continue to evaluate alternative NRP-1 assays. Feedback from the FDA reinforces the importance of these ongoing efforts prior to embarking on a pivotal trial. We look forward to continuing our dialogue with the Agency and cooperative groups toward the design and potential conduct of an appropriate confirmatory study and the development of a companion diagnostic.” (Original Source)

In reaction, shares of AVEO Pharmaceuticals are trading down 22.22% in after-market trading. AVEO has a 1-year high of $3.50 and a 1-year low of $0.61. The stock’s 50-day moving average is $1.82 and its 200-day moving average is $1.28.

On the ratings front, RBC analyst Adnan Butt upgraded AVEO to Hold, with a price target of $3, in a report issued on March 9. The current price target implies an upside of 38.2% from current levels. According to TipRanks.com, Butt has a total average return of -1.4%, a 51.0% success rate, and is ranked #2970 out of 3621 analysts.

AVEO Pharmaceuticals Inc is a biopharmaceutical company. It is involved in discovering, developing and commercializing novel cancer therapeutics.