Oxford Pharmascience (the sponsor) is developing a new formulation of Ibuprofen (OXP001 - the study drug) which it is proposed will have less of the side effects than are currently reported with standard prescription strength Ibuprofen.

This study will compare the study drug to an already marketed formulation of prescription strength Ibuprofen (the reference product) by looking at how the drug is taken up by the body and also by performing a specialist procedure called an endoscopy (or more specifically a gastroscopy). The safety and tolerability of the study drug will also be assessed.

The study will involve approximately 44 healthy male and female subjects. Subjects will be randomly assigned to receive either the study drug or reference product for 8 days. On Day 1, subjects will receive a single 800 mg dose of ibuprofen. On Days 2 to 9, subjects will receive 800 mg ibuprofen three times a day.

Inclusion Criteria:

• Healthy subjects
• Aged 18-55 years
• Normal, healthy upper gastrointestinal tract

Exclusion Criteria:

• History of or concurrent gastric irritation or ulcers
• History of allergy to non-steroidal anti-inflammatory drugs (NSAIDs)