Troubled Teva offers a surprise rival bid for NuPathe

Endo's ($ENDP) deal to buy NuPathe has triggered an unlikely bidding war. The troubled giant Teva Pharmaceutical Industries ($TEVA), which is struggling to restructure and launch new products, has come up with a much sweeter offer in the hope of landing a new migraine therapy.

In an SEC filing, Conshohocken, PA-based NuPathe ($PATH) revealed that Teva emailed an offer to buy the company and its pain patch Zecuity for $3.65 a share and an additional payout of up to $3.15 a share in contingent value rights if the product achieves certain sales milestones. That's considerably better than the $2.85-per share offer (plus $3.15 a share in potential sales milestones) that Endo needed to strike its takeover pact.

NuPathe shares shot up more than 30% this morning.

What's Teva after? The FDA approved Zecuity about a year ago as the first and only migraine pain patch, which delivers the widely prescribed sumatriptan through the skin. Endo was planning to launch the therapy in the next few months, but may have to revise its strategy in the wake of Teva's unexpected offer.

In addition to the sweetened per-share offer, Teva is adding 85 cents a share if sales of Zecuity break the $100 million mark over four consecutive quarters in the next 9 years, another $1 for $300 million and $1.30 for $450 million.

The biotech has traveled a long and rocky road to get to this point. The FDA initially rejected Zecuity back in 2011, citing safety concerns. NuPathe had to raise more cash, delay its other R&D work and cut half of its staff in order to regroup around the lead product. No one is paying much attention to its pipeline today, but NuPathe has preclinical efforts underway in Parkinson's and schizophrenia/bipolar disease.

- here's the SEC filing

Industry Voices: Industry Voices: Place your bets--A horse race emerges in the migraine space