ImClone Systems, Inc., which is counting on regulatory approval of a blockbuster cancer drug, got a vote of confidence from an analyst on Monday.

Cowen and Co. analyst Eric Schmidt upgraded ImClone shares to Outperform from Neutral, saying that study data from the Erbitux colon cancer drug is likely to be seen in a positive light by officials at the Food and Drug administration.

Erbitux is in the midst of clinical trials. Last September, ImClone and partner Bristol Myers Squibb Co. released results from a study which they said showed the drug increased the chances of survival for patients who had a common type of lung cancer.

Discussions with lung cancer specialists indicate that should FLEX (study data) demonstrate a modest growth improvement in median survival, the data will be viewed as clinically relevant, Schmidt said in a note to investors.

He believes Erbitux sales could range from $500 million to $1 billion, capturing 40 percent of the market from rival drug Avastin from Genentech, Inc.