FDA slaps Valeant with a warning letter. Will Allergan slap it, too?

In a protracted takeover battle and war for investors' favor, the last thing you want to do is give your opponent ammo. But Valeant Pharmaceuticals (VRX) may have done just that.

Tuesday, the company said the FDA had served up a warning letter about its Sculptra Aesthetic manufacturing, citing problems it observed during a June 2014 inspection. The missteps from manufacturing standards might just fuel the fire from hostile buyout target Allergan ($AGN).

Never mind that the letter pertains to the company's contract manufacturers, rather than Valeant's own internal manufacturing. Never mind that it doesn't prevent manufacturing or distribution of Sculptra--or any of Valeant's products, for that matter. And never mind that J. Michael Pearson's company unloaded Sculptra to Galderma in a deal this July.

As Pharmalot notes, Allergan still may use the letter to back up its argument that Valeant's business model---a.k.a. buying a company, slashing costs and moving on to the next--is not sustainable and would jeopardize Allergan's focus on things like R&D and patient safety. That's a tune Allergan has been singing for months now. Just this week, it attacked Valeant's sales model, claiming its rosy Q3 predictions weren't all the company claimed them to be.

But Allergan's manufacturing track record hasn't been spotless since Valeant made its first bid back in April, either. In early July, it received a complete response letter from the FDA, delaying approval of its inhaled migraine treatment over canister production concerns.

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