The FDA has approved Amgen’s colon-cancer drug Vectibix (panitumumab), setting the scene for a price war with rival drug Erbitux from Imclone Systems. Vectibix, the first cancer treatment from Amgen, is expected to be available by mid-October. To jump-start competition with Erbitux, Amgen will price Vectibix approximately 20% lower than its rival, at roughly $8,000 a month. Amgen CEO Kevin Sharer said Vectibix should generate as much as $2 billion in annual sales. Amgen acquired Vectibix in April when it acquired its maker, biotech firm Abgenix, for $2.2 billion. Erbitux, which was approved for use against colon cancer more than two years ago, brought in US sales of $413 million in 2005. It is sold by Bristol-Myers Squibb in the US and by Merck KGaA outside the US.