Shares in NuPathe has rocketed nearly 50% by late afternoon trading yesterday on news that the firm has caught the eye of Endo.

The companies have entered into a definitive agreement under which Endo will acquire NuPathe for $2.85 per share in cash, which equates to $105 million. 

The deal gets Endo access to NuPathe's migraine treatment Zecuity, the only FDA-approved migraine patch on the US market, and NuPathe shareholders will receive rights to additional cash payments of up to $3.15 per share if sales meet expectations.

Zecuity is a disposable, single-use, battery-powered transdermal patch that actively delivers sumatriptan, the most widely prescribed migraine medication, through the skin, which clinical trials showed to be effective at relieving pain and nausea two hours after activation.

Explaining Endo's interest in the deal, president and chief executive Rajiv De Silva expressed excitement at the opportunity to launch Zecuity, which "could be an option for millions of migraine patients, including those with migraine-related nausea".

Also, the move bolsters the firm's own branded pharmaceuticals portfolio, and falls in line with its strategy of acquiring late-stage products for commercialisation, he noted.

On the other hand, the deal "will increase the potential for Zecuity to make a meaningful difference for patients", said Armando Anido, NuPathe's CEO.

Endo plans to launch Zecuity during the first half of next year, leveraging its existing commercial expertise in pain and migraine management.

Just last month, the group announced plans to acquire Canadian specialty pharma Paladin Labs in a stock and cash transaction valued at around $1.6 billion, and its intention to form a new Irish holding company.