UPDATE 2-Roche to meet bond investors next week -sources

(Adds details on banks, background on Pfizer deal)

LONDON, Feb 12 (Reuters) - Swiss drugmaker Roche Holding AG (ROG.VX) is to hold a European roadshow next week for a bond issue to help fund its planned buyout of Genentech Inc DNA.N, three sources familiar with the situation said on Thursday.

Roche launched a hostile $42 billion tender on Monday for the 44 percent of the U.S. biotechnology group it does not already own.

Spokesman Daniel Piller confirmed the Basel-based company planned to go first to the bond market to secure financing, but declined to give details about any meetings or say how large the bond issue might be.

BNP Paribas and Deutsche Bank are among the banks managing the meetings, the sources said.

One person said Roche was likely to be looking for about $10 billion from the bond market and a $25 billion loan from a syndicate of 12 banks -- supplemented by $7 billion of its own cash -- to pay for Genentech.

This could be topped up by commercial paper and further cash on its balance sheet to put upwards of $50 billion at Roche's disposal, the source added.

Roche Chairman Franz Humer said last month the Swiss group planned to use a combination of its own funds, bonds, commercial paper and bank financing.

The hostile move on Genentech comes hot on the heels of an agreed deal for Pfizer Inc (PFE.N) to buy smaller rival Wyeth WYE.N for $68 billion, backed by a $22.5 billion loan.

The availability of funding for two such bumper acquisitions indicates that debt markets for cash-rich drugmakers are far from dead, although sources said the richly priced Pfizer loan could vacuum up cash and make financing more tricky for Roche.

Buying Genentech would give Roche control of all revenue for blockbuster cancer drugs Avastin and Herceptin, as well as an attractive portfolio of other medicines, and reflects the pharmaceutical industry's push to acquire biotech assets to fill sparse new-product pipelines.

Genentech gets U.S. revenue from its medicines, while Roche sells the drugs outside the United States.

Roche is offering $86.50 a share in cash for the rest of Genentech -- far short of the $112 Genentech's advisers suggested as a reasonable price and below the $89 proposed by Roche back in July. (Reporting by Tessa Walsh, Natalie Harrison and Ben Hirschler; Editing by David Holmes and Andrew Macdonald)