NEW YORK (CNN/Money) - Stocks headed higher at the open Monday, taking Friday's rally that brought the major indexes to multi-month highs one step further as investors awaited a national reading on manufacturing.

At 9:35 a.m. ET, the Dow Jones industrial average (up 61.69 to 8911.95, Charts) and the S&P 500 index (up 6.49 to 970.08, Charts) scored moderate advances, but the Nasdaq composite (up 15.90 to 1611.81, Charts), with a gain of more than 1 percent, moved to its highest level in a year.

At the close of trading Friday, the Dow stood at its best level in almost six months and the S&P 500 at its best level in nine months.

Investors eagerly awaited the Institute for Supply Management's index of manufacturing activity, due at 10 a.m. ET, after a Chicago area reading on Friday showed a big jump in the region. Economists expect activity rose in May to 47.6 from 45.4 in April, according to a consensus of economists polled by Reuters.

While Friday's report on Chicago-area manufacturing showed a rise above 50 -- a sign of expansion in the sector -- the national index is still expected to hold below that level.

Meanwhile, the dollar rallied against the euro but declined versus the yen. The dollar's gains were attributed to President Bush's comments over the weekend at a G8 meeting that seemed to support a strong dollar and contradicted recent comments by Treasury Secretary John Snow.

On the corporate front, biotech shares were among leading gainers.

Genentech (DNA: up $7.48 to $70.09, Research, Estimates) jumped more than 11 percent in early trading after the company presented findings at a weekend meeting of the American Society of Clinical Oncology that showed its experimental colon cancer treatment helped patients live 50 percent longer than standard chemotherapy.

In addition, ImClone (IMCLE: up $8.60 to $37.10, Research, Estimates) presented findings from a study by its European partner that showed its cancer treatment Erbitux was as effective as the company originally claimed. It's shares also rose nearly 30 percent at the open.

Elsewhere in the market, shares of business software maker J.D. Edwards (JDEC: up $1.48 to $13.29, Research, Estimates) soared after rival PeopleSoft (PSFT: down $0.67 to $15.72, Research, Estimates) said it would acquire the company for $1.7 billion in stock.

Walt Disney (DIS: up $0.28 to $19.93, Research, Estimates) shares rose more than 1 percent in European trading after the studio's latest collaboration with Pixar Animation Studios (PIXR: up $2.85 to $59.40, Research, Estimates), "Finding Nemo," set an opening record for an animated film of $70.4 million.

European markets were higher at midday, while Asian stocks finished higher Monday, with Tokyo's Nikkei rising 1.5 percent to close at a three-month high.

Treasury prices fell in early trading, with the 10-year note losing 10/32 of a point in price to yield 3.40 percent, up from 3.36 percent late Friday.

Brent oil futures for July delivery gained 23 cents to $26.55 a barrel in London. Gold for August delivery slipped $1.20 to $364.40 an ounce in New York.