PK Results for OXPzero Naproxen vs. Naprosyn

Oxford Pharmascience Group plc

("Oxford Pharmascience" or "the Company")

Pharmacokinetic (PK) Study Resultsfor OXPzero™ Naproxen vs. Naprosyn®

Oxford Pharmascience, the specialty pharmaceutical company that redevelops medicines to make them better, safer and easier to take, is pleased to announce the positive full results of the pilot comparative pharmacokinetic (PK) study for OXPzeroTM Naproxen (OXP005), which - based on mean values - demonstrates an immediate release profile and bioequivalence to standard US and EU naproxen treatment.

OXP005 delivers 250mg of reduced gastric irritation naproxen via the Company's patent protected OXPzero™ technology. The full results of the study follow on from the headline data previously announced on 27 March.

The two-arm, pilot PK study was conducted in 10 healthy adult participants with each subject receiving both the OXP005 and the Naprosyn® treatments in a crossover design. The PK data show that all subjects had equivalent absorption of naproxen from OXP005 and of Naprosyn®, as indicated by area under the curve (AUC), with OXP005 being 100.5% of that observed for Naprosyn®. Mean maximum concentrations (Cmax) were 82.8% of that observed with Naprosyn®. In addition, both the mean half-life, time to maximum concentration and time to first measurable naproxen levels for OXP005 were comparable to Naprosyn®.

The amount of naproxen contained within the OXP005 tablets used for the PK trial was slightly low at 95.5% of the target naproxen dose, due to low tablet weight. Adjusting the PK results to account for the actual naproxen dose in both products tested provides mean relative values for absorption (from the AUC measurements) and maximum concentration (Cmax) of 102.8% and 84.3% respectively. The mean values for AUC and Cmax are within the guidelines for bioequivalence (80.0 to 125.0%). The fully powered bioequivalence study in later development will be designed to show that the 90% confidence intervals also fall within these limits, as per the FDA and EU guidelines.

These pilot PK study results demonstrate that, based on mean values, OXP005 is bioequivalent to Naprosyn® and therefore the Company is progressing to a proof of concept endoscopy study comparing the extent of gastroduodenal irritation between the OXP005 and Naprosyn. Dosing for this study is on track to start imminently with approvals required for the study in place and potential study subjects identified.

Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the most widely used classes of drugs, with more than 30 million users worldwide consuming NSAIDs each day and combined annual sales in excess of $12 billion (source: Evaluate Pharma). However, chronic use of NSAIDs causes well-documented gastrointestinal side effects, including ulcers and bleeding, and leads to significant morbidity and mortality in a substantial number of patients, with significant healthcare costs arising as a result of these side effects. The OXPzero™ platform technology reduces these risks and is being selectively applied to the most commonly used molecules in the NSAID category, namely ibuprofen, naproxen, diclofenac and aspirin.

Naproxen is an important NSAID with total sales of c $1bn at MSP (manufacturers' selling prices), mostly in North America.1 Naproxen was first approved for prescription use in the US in 1976 and was made available for OTC use as Aleve® (naproxen sodium 220 mg) in the US in 1994. Outside North America, naproxen is mostly used by prescription only. While naproxen has a somewhat higher risk of causing adverse GI effects as compared with ibuprofen2 it has some distinct advantages: Naproxen offers longer lasting relief and therefore requires less frequent dosing. Importantly, based on published analysis, naproxen is thought to have a reduced risk of cardiovascular events than all other NSAIDs3. It is therefore the preferred NSAID for long-term use in people with a high risk of cardiovascular complications4 and increasingly the preferred prescription option for patients with chronic conditions commonly treated with NSAIDs.

Marcelo Bravo, Chief Executive Officer of Oxford Pharmascience commented: 

"These pilot study results with OXP005 support further development of our gastric safe naproxen and support our vision to revolutionise the NSAID treatment market. We are advancing development of a new pain relief treatment option for patients that offers improved gastrointestinal safety over the well-known NSAIDs, leading with the NSAID offering the safest cardiovascular profile, naproxen."

1. Euromonitor & Evaluate Pharma

2. Individual NSAIDs and Upper Gastrointestinal Complications, A Systematic Review and Meta-Analysis of Observational Studies (the SOS Project), Drug Saf. 2012; 35(12): 1127-1146. Published online 2012 Dec 13. doi: 10.1007/BF03261999

3. ALEVE® & NAPROSYN® ANAPROX® , Briefing Document for US Food and Drug Administration Advisory Committee Meeting, Bayer Healthcare LLC, Consumer Care Division Whippany, New Jersey and Hoffmann-La Roche Inc. Nutley, New Jersey ADVISORY COMMITTEE BRIEFING MATERIALS, 10 January 2014

4. Primer: managing NSAID-induced ulcer complications-balancing gastrointestinal and cardiovascular risks, Nature Clinical Practice Gastroenterology & Hepatology (2006) 3, 563-573

doi:10.1038/ncpgasthep0610 doi help removed

Received 4 January 2006 | Accepted 25 July 2006

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About Oxford Pharmascience Group Plc

Oxford Pharmascience Group Plc uses a range of proprietary technology platforms to re-develop existing medicines to make them better, safer or easier to take. The Company does not manufacture or sell its own pharmaceutical products direct to consumers but instead seeks to license its technologies and dossiers to a network of partners, mainly leading pharmaceutical companies with Rx (prescription) and OTC (Over the Counter) branded portfolios.

Oxford Pharmascience Group Plc focuses on existing medicines that are proven to be safe and effective but nevertheless still have associated issues and side effects often affecting compliance. By working with such medicines the Company is able to develop new innovative products for a fraction of the cost, in much quicker timescales and without the high risk of failure associated with developing new drugs.