EKR Therapeutics, a Cedar Knolls, N.J., specialty pharma founded in 2005, just raised an undisclosed sum in debt and equity financing in order to buy several heart drugs from PDL BioPharma, an unraveling biotech that is selling off assets in a restructuring. The twist here is that PDL originally acquired one of those drugs, a high blood-pressure treatment called Cardene, when it purchased another specialty pharma called ESP Pharmaceuticals in early 2005. That company, it turns out, was co-founded by none other than the current CEO of EKR, Howard Weisman.

EKR is getting its old drug back for a song. The comany will pay PDL $85 million upfront and up to another $85 million contingent on the successful development of new Cardene formulations and commercial sales milestones. (Three years ago, by contrast, PDL paid $475 million in cash and stock for ESP Pharma.) As part of the current deal, EKR is also acquiring Retavase, a clot-busting drug, and ularitide, an experimental heart-failure drug.

PDL, which hit the wall when a promising drug hit safety problem and its CEO resigned following a dust-up with an activist investor in the company, has now sold off all its existing commercial products. According to Wachovia Capital analyst George Farmer, who spoke to BusinessWeek, PDL now has no “meaningful” assets beyond a royalty stream deriving from its early discovery of ways to make antibody-based drugs more effective, a new manufacturing plant and roughly $200 million in net cash — plus $685 million of estimated operating losses. (The company has drugs in development, but opinions vary widely as to whether they’ll ever see the light of day.)

Weisman, meanwhile, is so happy to have Cardene back that he now expects EKR’s revenues to increase “ten-fold” as a result of the deal. That’s a pretty bullish assumption, particularly given that Cardene’s patent expires next year. (The new formulations are undoubtedly intended to extend that patent lifetime, although recent court decisions limiting the patentability of “obvious” modifications may make that more difficult.) Still, it’s got to be sweet to have a chance to profit a second time from the same drug.