This is the story that just won’t go away. We recently wrote about Botox maker Allergan rejecting a takeover bid by Canadian pharmaceutical company Valeant. But it seems Valeant have rhino hide, and won’t be letting rejection put them off.

It’s been reported that the conglomerate will this week launch an exchange offer for Allergan Inc, which will allow them to bypass the board of Directors and take their hostile bid directly to shareholders.

Allergan has already rejected Valeant’s $53 billion offer, but the company’s largest shareholder, Pershing Square Capital Management, has indicated it will be seeking a special meeting later this year to change most of Allergan’s board.

To trigger the meeting, Pershing needs to ensure the support of 25% of Allergan’s shareholders – an increase of 15.3% on its own holding of 9.7%.

Despite the challenge ahead, Valeant’s Chief Financial Officer Howard Schiller is bullish about their chances of shoring up the support. He pointed out that more than 50% of Allergan’s shares have traded since news of Valeant’s offer first leaked out on 21st April.

Talking about the controversy surrounding their approach to Allergan, Valeant’s Chief Executive Officer Mike Pearson, said:

“Hostile is not our preferred approach. But this deal was so strategic and financially compelling that it really makes sense.”

It increasingly seems that it’s a question of when, not if, this deal will finally go ahead.