Endo International has succeeded with a sweetened bid to acquire the USA's Auxilium Pharmaceuticals in a cash-and-stock transaction valued at $2.6 billion.

Last month, the Ireland-domiciled group’s $2.2 billion offer was rejected by Auxilium, which was itself planning to acquire Canadian eye specialist QLT, a deal that would have lowered its taxes. However the new $33.25 bid by Endo, which represents a 55% premium to Auxilium's closing price on September 16, has won the day.

Auxilium has now called off its proposed merger with QLT, which will receive a $28.4 million termination fee. Endo said the deal, which is expected to be immediately accretive after closing next year, will generate about $175 million in annual cost savings.

Auxilium’s lead drug is Xiaflex (collagenase clostridium histolyticum). It is approved in the USA for Dupuytren's contracture, which affects the connective tissue beneath the skin in the palm of the hand, and Peyronie's disease, which causes a bothersome curvature of the penis during sex. It has a total of 12 Food and Drug Administration-approved products, including Stendra (avanafil), an oral erectile dysfunction drug.

Meantime, generics firm Impax Laboratories is spending $700 million to acquire Tower Holdings (including its subsidiaries CorePharma and Amedra Pharmaceuticals) and Lineage Therapeutics.

The deal gives Impax access to a “highly-profitable portfolio” that consists of four branded products, including Albenza (albendazole) for invasive tapeworm infections, seven complimentary commercialised generics and an epinephrine auto-injector product. This portfolio, in combination with “several products that the companies plan to launch during the fourth quarter of 2014” are expected to generate 2014 revenues of $215-$225 million.