Shares of Intermune ( ITMN) were under heavy selling pressure Thursday, a day after the biopharma company lowered its full-year revenue outlook because of weaker-than-expected sales of its key drug Actimmune.

The company now expects $145 million to $165 million in total product revenue in 2003. In April, the company had said product sales would be $170 million to $195 million for the year. At least five Wall Street firms, including Banc of America, Bear Stearns and RBC Capital Markets, lowered their ratings on the stock following the news.

Lately the stock was dropping $7.49, or 30%, to $17.61. More than 13 million shares of Intermune had traded by midday. During an average Nasdaq session, a little more than 700,000 shares trade. Intermune's stock has so far traded in a range of $17.25 to $18.24 today.

Broad biotech sector measures were also giving up ground. The Amex Biotech Index was losing 1.3% and the Nasdaq Biotech Index was down 0.3%.

Despite the big decline in Intermune and the sluggishness in the sector overall this day, the biotechs have been running higher for the last several weeks, and some analysts expect that trend to continue. Established companies have seen investors flock to their shares in 2003, as have some of the smaller and, in some cases, more speculative names.

One of the small-cap stocks going higher today was Ariad Pharmaceuticals ( ARIA), which rose 7% to $4.70 after saying it expects $1 million in license payments over the next 20 months.

Elsewhere in the sector, Cell Therapeutics ( CTIC) was gaining 12% to $13.63 on word the Food and Drug Administration approved the company's supplemental new drug application related to the manufacturing and labeling of leukemia drug Trisenox. Curis ( CRIS) jumped 30% to $4.90 after striking a licensing deal with Genentech ( DNA).

Meanwhile, generic drugmakers were attracting buying interest on hopes that President Bush will call for new rules that ultimately will make the companies more competitive with brand-name pharmaceutical manufacturers by speeding generic drug approvals.

Teva Pharmaceuticals ( TEVA) was gaining 6% to $54.60, Mylan Labs ( MYL) was up 4% to $33.10, and Taro Pharmaceutical Industries ( TARO) was higher by 5% at $54.73. Pharmaceutical Resources ( PRX) was better by 3% at $46.75, and Barr Labs ( BRL) was adding 3% to $63.14.

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