Shares of Dynavax Technologies ( DVAX - Get Report) surged more than 50% in after-hours trading Wednesday after the biopharmaceutical company announced positive results in a phase II trial of Tolamba, its experimental hay fever drug.

In the two-year study, Tolamba significantly reduced patients' nasal symptoms compared with those treated with a placebo, Dynavax said. The company plans to start a phase III trial for the drug in the first half of this year. Shares jumped $2.25, or 52%, to $6.60 in late trading.

Hutchinson Technology ( HTCH) slipped after the company posted a sharp drop in its fiscal first-quarter profit and projected second-quarter earnings below Wall Street's forecasts. The company, which supplies suspension assemblies for disk drives, reported a profit of $6.1 million, or 22 cents a share, down from net income of $13.4 million, or 47 cents a share, in the year-earlier period. Excluding stock-compensation expenses, earnings were 24 cents a share, topping Thomson First Call's mean analyst estimate by 4 cents. Revenue for the quarter ended Dec. 25 increased 27% to $184.6 million.

For the second quarter, Hutchison projects earnings of 15 cents to 30 cents a share, below analysts' projection of 31 cents. The company anticipates sales, however, of $190 million to $205 million, above Wall Street's prediction of $179.7 million. Shares fell 62 cents, or 2%, to $30 in after-hours trading.

Shares of Spansion dropped after the semiconductor maker said its fourth-quarter loss widened to $48 million, or 63 cents a share, from $26.6 million, or 37 cents a share, a year earlier. Sales rose 15% to $592 million. Spansion, which is majority owned by Advanced Micro Devices ( AMD - Get Report), fell 66 cents, or 4.7%, to $13.25 in after-hours trading.

Lam Research ( LRCX - Get Report) rose after the semiconductor designer beat analysts' second-quarter earnings expectations. Lam earned $77.8 million, or 55 cents a share, for the quarter ended Dec. 25, compared with $83.6 million, or 59 cents a share, a year ago. Analysts expected the company to post earnings of 39 cents a share. Revenue for the quarter was $358.2 million, down from $379.8 million a year ago but above Wall Street's target of $344.1 million. Shares of Lam Research rose $3.69, or 9.6%, to $42.01 late Wednesday.