Valeant Pharmaceuticals has confirmed it is set to return with a fresh bid for Allergan, the company behind the Botox anti-wrinkle treatment.
Canadian firm Valeant has already had one offer for the business turned down, but the company revealed that it is planning to go back in with another bid by the end of the month.
Allergan rejected the $47 billion (£27.9 billion) offer for its business from Valeant, but may come under increasing pressure in the next few weeks to sell up to the larger firm.
Valeant said in a letter posted to its shareholders that the offer made recently was rejected without Allergan having had any discussions with Valeant.
Chief executive of Valeant Michael Pearson said in the statement: "We will not stop our pursuit of this combination until we hear directly from Allergan shareholders that you prefer Allergan's 'stay the course plan' to a combination with Valeant."
Allergan board chair and chief executive David E.I. Pyott stated that Valeant's proposal creates "significant risks and uncertainties" and this is why it has been turned down by the board. He added that the board of the firm "believes that the Valeant business model is not sustainable".
The share price of Valeant Pharmaceuticals fell by 0.4 per cent yesterday, with the firm suffering from a further 0.04 per cent drop in the value of its stocks in after-hours trading.
Mr Pearson added that Valeant remains "resolute" in its attempts to purchase the Botox company, noting: "We are excited about the value creation opportunity for all shareholders from the enormous strategic and financial synergies that result from this transaction."
Valeant has a target of becoming the fifth largest pharmaceutical company in the US in the next few years and in a bid to hit that goal, the firm recently bought eye health company Bausch & Lomb. Headlines are currently being made in the UK by US company Pfizer, which has had an initial offer for British drugmaker AstraZeneca turned down.
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