UPDATE 1-Daiichi Sankyo buys 63.9 pct stake in Ranbaxy

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TOKYO Nov 7 (Reuters) - Daiichi Sankyo Co (4568.T), Japan's No. 3 drugmaker, said on Friday it had completed the takeover of India's Ranbaxy Laboratories Ltd (RANB.BO), buying a 63.9 percent stake for 199.8 billion Indian rupees ($4.20 billion).

Daiichi Sankyo agreed with the generic drugmaker in June to buy a stake of at least 50.1 percent for up to $4.6 billion through a tender offer, the private placement of new shares and the purchase of outstanding shares from the founding family.

The Japanese firm bought Ranbaxy, seeking to secure revenue streams over a long run amid intensifying competition and price pressure in the branded drug market globally.

Daiichi Sankyo, which last week cut its full-year earnings forecast because of costs to buy German biotech firm US Pharma AG, plans to unveil the impact of the Ranbaxy deal on its earnings in January.

It could book in the year to March an appraisal loss on the owenership of Ranbaxy shares, which it bought for 737 rupees each, as they have plunged to less than a third of the price amid a scandal in the United States and a stock market meltdown. (Reporting by Yumiko Nishitani)