Just over 13 months after the original deal was made, in August 2006, POZEN and AstraZeneca have mutually agreed to amend certain terms of their collaboration and licence agreement for the development and commercialisation of PN 400, a fixed dose combination of the proton pump inhibitor esomeprazole magnesium with the NSAID, naproxen, in a single tablet. The product is indicated for the management of pain and inflammation associated with conditions such as osteoarthritis and rheumatoid arthritis in patients who are at risk for developing NSAID-associated gastric ulcers. The value of the changed deal terms to both POZEN and AstraZeneca is discussed, and other comparable deal amendments are outlined.