NicOx announces U.S. phase 2a results for PF-03187207 and gives an update on continuing NO-prostaglandin program

www.nicox.com

NicOx S.A. (Euronext Paris: COX) today announced the results of a U.S. phase 2 study, conducted by its partner Pfizer Inc, which compared the safety and efficacy of various doses of PF-03187207 to Xalatan® (latanoprost) 0.005% in patients with primary open-angle glaucoma and ocular hypertension. The higher doses of PF-03187207 demonstrated a clinically significant reduction in diurnal intraocular pressure (IOP) from baseline and the highest dose showed consistently more IOP lowering than Xalatan® 0.005%, at all study visits and at all individual time points, suggesting a beneficial effect of nitric oxide donation. PF-03187207 is a nitric oxide-donating prostaglandin analog, which is covered by the companies' August 2004 agreement.

On the primary endpoint at 28 days, PF-03187207 showed a 12% improvement over Xalatan® 0.005% which did not reach statistical significance. However, a statistically significant advantage over Xalatan® 0.005% was observed on a number of secondary endpoints (p < 0.05).

Pfizer has taken the decision not to launch a global phase 3 development program for PF-03187207. Nevertheless, Pfizer has reaffirmed its commitment to the ongoing joint research program with NicOx, which aims to identify the most active nitric oxide-donating prostaglandin analogs for development on a global basis.

David Eveleth, Vice-President, Ophthalmology Development at Pfizer, commented: "We believe this phase 2 study for PF-03187207 has provided interesting data. While the study did not meet its primary clinical endpoint and our criteria for launching a global phase 3 program for this compound, we remain committed to our joint research program with NicOx, where the follow-up compounds to PF-03187207 have produced encouraging results."

The research to identify improved nitric oxide-donating prostaglandin analogs is one of the programs covered by the companies' March 2006 agreement. Several follow-up compounds from this agreement have generated promising results in a validated in vivo model of abnormally high IOP, compared to a commonly used reference drug. Pfizer's option to obtain an exclusive worldwide license to these compounds currently runs until May 2009 and their successful development and launch would result in milestone payments of EUR 102 million and industry standard royalties on sales.

Pfizer is currently conducting a phase 2 study for PF-03187207 in Japan and has indicated that it would consider continuing the development of PF- 03187207 for potential registration in Asia, including Japan, depending on the results of this study which are expected in Q3 2008. NicOx and Pfizer are currently in discussions regarding the rest-of-world rights to PF- 03187207. Asia currently accounts for 20% of Pfizer's Xalatan® sales (source: IMS) (see NOTE).

Michele Garufi, Chairman and Chief Executive Officer of NicOx, commented. "We believe these results for PF-03187207 suggest nitric oxide donation can bring therapeutic benefit through improved intraocular pressure lowering. Although Pfizer has decided that PF&#8209;03187207 does not meet its specific requirements for the US and European markets, we believe this phase 2 study demonstrates a clear commercial potential for PF-03187207 and we are exploring possible strategies with Pfizer to unlock this value. Moreover, the promising results from our joint research program make us confident that a follow-up candidate will be selected by Pfizer with the potential for further improvement over existing treatments."

Results of the U.S. phase 2 study

The phase 2 dose-finding study for PF-03187207 was initiated in the United States in March 2007 and was designed to compare the safety and efficacy of several doses of PF-03187207 to the marketed dose of Xalatan® 0.005%. The randomized, double masked study enrolled 215 patients with primary open- angle glaucoma or ocular hypertension, in one or both eyes. Patients were randomized to receive 28 days of treatment with either morning or evening doses of Xalatan 0.005%, or various doses of PF-03187207 (five different doses of PF-03187207 were tested, some of which were tested with both morning or evening dosing arms). Patients' IOP was measured at 8am, 10am, 1pm and 4pm, at baseline and on days 7, 14, 21 and 28.

The primary objective of the study was to determine if any PF-03187207 dose was superior to Xalatan® 0.005% for the reduction of elevated diurnal IOP (mean over the day, based on the values obtained at 8am, 10am, 1pm and 4pm) and the primary endpoint compared the two treatments in terms of the change in mean IOP from baseline at day 28. On this primary endpoint, evening administration of the highest dose of PF-03187207 showed a 12% (approximately 1 mmHg) greater reduction in diurnal IOP than evening administration of Xalatan® 0.005%, although this difference did not reach statistical significance.

On a secondary endpoint of the study (IOP lowering from baseline at 4 pm, as an average across all study visits), evening administration of PF- 03187207 was statistically significantly better than evening dosing of Xalatan® 0.005% by 22%, which was approximately 1.4 mmHg in absolute terms (p < 0.05). This difference occurred approximately 20 hours after study drug administration, suggesting a potential clinical advantage for PF- 03187207.