AstraZeneca has unveiled plans to start a Phase III clinical trial programme for PN400, a pain drug in development under a partnership with US group Pozen.

The UK drug giant said it will launch the programme in the third quarter of this year, and that a submission to US regulatory authorities is planned for the first half of 2009.

PN 400 combines naproxen and esomeprazole in a single pill using Pozen’s proprietary formulation technology, and is targeted for patients with arthritic pain who need chronic non-steroidal anti-inflammation drug treatment but are at risk from developing gastric ulcers associated with this class of analgesics.

The groups sealed their research pact to develop the combination in August last year, but have since amended the terms of their agreement. AstraZeneca will now pay Pozen: $30 for successful proof-of-concept; $55 million on achievement of certain development and regulatory milestones; and $260 million as sales performance milestones if certain goals are met. Under the original terms, development and regulatory milestones totalled $160 million while sales performance ones totalled $175 million.

New royalty structure

In addition, the groups have also amended the royalty structure in the US, switching from a tiered model to one low double-digit rate for the life of the partnership. But the multi-tiered structure has only had some minor changes in other regions, with royalties ranging from mid-single digits to high-teens, the groups said.

Both companies are stumping up cash for the drug’s development, with Pozen taking responsibility for the USA and AstraZeneca elsewhere, although the UK group will take charge of all aspects of manufacturing, marketing, sales and distribution on a worldwide basis By Selina McKee

FluMist manufacturing problems sorted out

Meantime, MedImmune, which was recently acquired by AstraZeneca, in a $15.2 billion deal, says that it has “resolved the observations” made by the US Food and Drug Administration in a warning letter in May during an inspection of the company's manufacturing facility in Speke, UK, where its FluMist influenza vaccine is made.

MedImmune noted that it is currently working with the FDA to make sure that shipping of FluMist to customers can soon begin for the upcoming influenza season. The firm added that it can now also take the necessary regulatory steps to seek the agency’s final approval of the company's supplemental biologics licensing application requesting expansion of the vaccine's indication to include children below the age of five.