UPDATE 1-Daiichi, Ranbaxy say deal is final but shares fall

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NEW DELHI, July 17 (Reuters) - Daiichi Sankyo (4568.T) and Ranbaxy Laboratories (RANB.BO) on Thursday said the Japanese drugmaker's deal to take over the Indian firm was "binding and final", but the statement failed to halt Ranbaxy shares slide.

Shares in Ranbaxy, India's leading drugmaker by sales, erased early gains and fell more than 8 percent in the morning on uncertainty over a U.S. investigation into allegations the company had introduced adulterated and misbranded drugs.

Details of the investigation had sent Ranbaxy shares tumbling 23 percent on Monday and Tuesday on concerns it would derail the $4.6 billion deal by Daiichi to take a controlling stake and also that its generic sales in the key U.S. market could be affected.

On Wednesday, Ranbaxy shares had rebounded 15 percent after Chief Executive Malvinder Singh said it would give U.S. authorities all information needed for the probe within the next month and that the Daiichi deal was on track.

"Daiichi Sankyo, Ranbaxy and the Singh family stand by the deal and confirm that the terms of the deal remain unchanged," the two companies said in joint statement said on Thursday.

The Singh family is currently the largest shareholder of Ranbaxy.

By 0619 GMT, Ranbaxy shares were down 4.1 percent at 451.25 rupees after falling as much as 8.4 percent. The stock had risen 5 percent in early trade.

"There is still uncertainty, so it's kind of wait and watch," said K.K. Mital of Globe Capital.

Shares in Daiichi Sankyo in Tokyo were down 1.7 percent. (Reporting by Devidutta Tripathy; Editing by Ranjit Gangadharan)