UPDATE 1-Crucell shares surge on Wyeth takeover talks

* Value may reach 1.3 billion euros or more

* Crucell shares at 16-month high on Wyeth talks

* Talks may trigger bidding war

(Adds analyst comment, background, updates shares)

By Harro ten Wolde

AMSTERDAM, Jan 8 (Reuters) - Shares in Dutch biotechnology firm Crucell (CRCL.AS) rose 35 percent on Thursday after the company said it was in talks with U.S. drug maker Wyeth WYE.N about a takeover of the Leiden-based company.

"My impression is Crucell will play hard to get and eventually Sanofi or Novartis will appear in the stage," Petercam analyst Jan van den Bossche said.

Crucell, which was valued at 757 million euros ($1 billion) before news of merger talks hit, is seen fetching at least 1.3 billion euros. Crucell said late on Wednesday that discussions were at a preliminary stage. [ID:nN07501131]

The bid for Crucell underlines the big drug companies' growing appetite for vaccines -- once viewed as a low-margin, slow-growing business -- but now offering some of the best prospects for promising new products.

Crucell is developing an influenza vaccine with Sanofi-Aventis (SASY.PA), based on its PER.C6 gene technology, which uses human cells as a platform to produce drugs.

Novartis (NOVN.VX) provides four of the five vaccine components of Quinvaxem, a vaccine cocktail for the childhood diseases diphtheria, tetanus, whooping cough and hepatitis B.

Shares in Crucell were up 35 percent at 15.78 euros at a 16-month high by 0928 GMT, outperforming a 2 percent higher Amsterdam midcap index .AMX.

MORE THAN 20 EUROS/SHR

The Wall Street Journal, citing persons familiar with the situation, said in its online edition late on Wednesday that a deal which could be reached within a week, could be valued at more than $1.35 billion.

Van den Bossche said the number appeared to be a little on the low side. "Shares could go to more than 20 euros in case of a bidding war," he added, which would value the company at 1.3 billion euros ($1.8 billion).

Wyeth is one of the world's most prominent vaccine makers, whose products include the blockbuster Prevnar vaccine to protect infants and young children from infections with pneumococcal bacteria.

Crucell is one of the world's few remaining independent vaccine makers. Another one is Austria's Intercell (ICEL.VI), whose shares were up 6.3 percent at 24.00 euros on the news.

Crucell posted its first-ever quarterly profit in November boosted by strong sales in its Quinvaxem, which was acquired in 2006 through the acquisition of Berna Biotech. ($1=.7332 euros) (Additional reporting by Ben Hirschler; Editing by Mike Nesbit)