We continue to have a Neutral recommendation on Regeneron Pharmaceuticals Inc. ( REGN ) following the appraisal of fourth quarter and full-year 2011 results.

Regeneron suffered a wider year-over-year loss in the final quarter of 2011. The wider loss was attributable to higher operating expenses and lower revenues. (Read our full coverage of the earnings report at Regeneron's Loss Widens, Eylea Grows ).

Going forward, we expect investor focus to be on the sales ramp of eye-drug, Eylea, which was launched in the US in November 2011. Eylea, marketed for treating patients suffering from the neovascular form of age-related macular degeneration (wet AMD), registered sales of $24.8 million in the final quarter of 2011.

Encouraged by the initial sales ramp and the increased demand for the drug, which has been co-developed by Regeneron with the HealthCare unit of Bayer ( BAYRY ), management nearly doubled its 2012 projected Eylea sales to $250-$300 million on the fourth quarter conference call from $140-$160 million provided at the global healthcare conference of JPMorgan ( JPM ) in January 2012. We too expect Eylea to continue performing well thereby boosting the top line at Regeneron.

Moreover, the US approval of Eylea has provided additional options for patients suffering from the eye-disease, which currently has limited treatment options. Roche/Novartis ' ( RHHBY / NVS ) Lucentis is the key player in the wet AMD market. Eylea is under review for the wet AMD in other markets as well such as Japan and the EU. Approval in additional markets would strengthen Regeneron's top line further.

2012 is expected to be a key year for Regeneron with two key action dates coming up as it seeks to expand the labels of both its marketed drugs, Arcalyst (currently marketed for cryopyrin-associated periodic syndromes) and Eylea.

The FDA is expected to decide on Regeneron's marketing application to get Arcalyst approved for preventing gout flares in patients initiating uric acid-lowering therapy by July 30, 2012. The agency will decide on Regeneron's application to get Eylea cleared for the central retinal vein occlusion indication by September 23, 2012. Moreover, we are also impressed by Regeneron's efforts to develop the other candidates in its pipeline.

However, we prefer to adopt a wait-and-see approach if Eylea meets management expectations and realizes its commercial potential. Moreover, since multiple pipeline related news is expected in 2012, any negative news will pull down the stock. Consequently, we believe the stock to be fairly valued at current levels and hence retain our Neutral view on it.