Timeline on regorafenib (Stivarga) development

Three months after landing FDA fast-track review status for regorafenib, Bayer's top cancer prospect, today the agency delivered an approval as a treatment for colorectal cancer. The approval comes after a tumultuous lawsuit filed in 2009 by Onyx Pharmaceuticals ($ONXX), claiming the compound can be distinguished from Nexavar by only a single atom. Here's a look back at regorafenib's history:

May 15, 2009 
Onyx Pharmaceuticals files a complaint in the U.S. District Court for Northern California alleging that the compound regorafenib can be distinguished from Nexavar by only a single atom. Report

May 7 2010
Germany's Bayer Schering Pharma marches ahead into a Phase III study of regorafenib for colorectal cancer, gambling it can successfully fend off a legal attack from its U.S. partner Onyx. Onyx filed suit against Bayer in 2009 saying the new cancer drug can be distinguished from Nexavar by only a single atom. Report

February 4, 2011
Regorafenib is granted orphan drug status for the treatment of patients with gastrointestinal stromal tumors by the FDA. Report

May 10, 2011
Bayer Healthcare receives the FDA's fast track designation for regorafenib. This comes after the company initiated a randomized, double-blind, placebo-controlled Phase III study of the drug in January. Report

October 12, 2011
Bayer and Onyx patch up the long-running dispute over who owns the rights to a Phase III cancer drug. Bayer retains control of regorafenib's development and commercialization efforts, while Onyx gets a hefty $160 million check and a promise of up to $15 million more, a 20% royalty share on worldwide sales and rights to co-promote the treatment in the U.S. Report | See the 8-K

October 26, 2011
Investigators say regorafenib hit its primary endpoint for improving overall survival among metastatic patients, triggering a move to unblind the study and offer the drug to patients in the placebo arm. Report

December 20, 2011
Bayer predicts that four of its late-stage programs--including regorafenib--are likely blockbusters. The company commits 2 billion euros, or two thirds of its total R&D budget, for drug research in 2012. Report

January 18, 2012
Investigators report that regorafenib improved the median overall survival rate of metastatic patients by 29%, with the drug arm demonstrating a 6.4 month overall survival rate while advanced patients who had already failed standard therapy survived a median average of 5 months on a placebo. Report

April 3, 2012
In a trial, Dana Farber's George Demetri studied regorafenib in advanced cancer patients who weren't responding to existing medications. Bayer says the treatment hit its primary endpoint on progression-free survival. Report

June 3, 2012
Regorafenib offers late-stage data which show the drug put the brakes on stomach cancer among a group of patients who had failed two standards of care. The median progression-free survival time for the regorafenib arm of the study was 4.8 months compared to only 0.9 months in the placebo arm. Report

June 28, 2012
FDA gives regorafenib promising treatment priority review status, which is projected to shave four months off the standard 10-month review. That lands the deadline for a marketing decision in late October. Report

August 30, 2012
Bayer files for approval of regorafenib to treat gastrointestinal cancer. Report