AstraZeneca and Nektar Therapeutics have entered into an exclusive worldwide licence agreement for two drug development programmes developed by Nektar.

The first programme involves NKTR-118, a late-stage investigational product being evaluated for the treatment of opioid-induced constipation. The second involves NKTR-119, an early-stage programme aimed at treating pain without constipation side effects.

Nektar Therapeutics president and chief executive officer Howard W Robin said that AstraZeneca is the ideal development and commercial partner for the NKTR-118 and NKTR-119 programmes.

“This partnership validates Nektar’s successful strategy to create novel oral small molecule drug candidates with our advanced polymer conjugate technology platform,” Robin said.

Under the terms of the agreement, AstraZeneca will assume responsibility for the continued development of the NKTR-118 and NKTR-119 programmes, including late-stage clinical studies for NKTR-118.

Nektar will receive an upfront payment of $125m for NKTR-118 and NKTR-119. Nektar will also be eligible to receive up to $235m in aggregate milestone payments, as well as additional tiered sales milestone payments of up to $375m based on commercial success.

Nektar will also be eligible to receive significant double-digit royalty payments on net sales of NKTR-118 worldwide.

AstraZeneca will be responsible for global manufacturing and marketing for both programmes and has announced that the design of the Phase III programme will be completed in the near term, with an official drug filing set for 2013.