SkyePharma PLC welcomes announcement by its partner GlaxoSmithKline that the US Food & Drug Administration (FDA) has approved an additional therapeutic application for Paxil CR (paroxetine hydrochloride Controlled Release) for the intermittent treatment of premenstrual dysphoric disorder (PMDD). Paxil is a leading selective serotonin reuptake inhibitor (SSRI) antidepressant and Paxil CR is in the US for the treatment of depression, panic disorder, social anxiety and for the continuous treatment of PMDD. SkyePharma developed the controlled release formulation used in Paxil CR and receives a royalty on GlaxoSmithKline's sales.

Michael Ashton, SkyePharma's chief executive officer, commented: "Paxil CR is currently our leading source of royalty income. According to IMS market data, Paxil CR accounts for about one in twelve new US prescriptions for SSRI antidepressants. The intermittent PMDD indication for Paxil CR should expand the market opportunity for the product since the original version of Paxil was never approved for the PMDD indication.''

PMDD is a condition that affects about 5 per cent of menstruating women and is characterised by severe and disabling mood swings and physical symptoms around the end of the menstrual cycle. With the new intermittent dosing option, women suffering from PMDD can take Paxil CR once a day during the two week period prior to the onset of their menstrual cycle rather than throughout the month.

In Paxil CR GlaxoSmithKline's SSRI antidepressant Paxil was reformulated using SkyePharma's Geomatrix oral drug delivery technology in which a multi-layered tablet controls the rate of dissolution and site of absorption of the drug in the body. Clinical studies have demonstrated that Paxil CR significantly reduces the incidence of nausea, a common and troublesome early side-effect that results in poor compliance with many SSRI antidepressants. The low drop-out rate for patients on Paxil CR may increase the likelihood that patients will obtain the full therapeutic benefit. For example, a study published in the February 2004 issue of the Journal of Clinical Psychiatry on the use of Paxil CR in treating social anxiety disorder showed that about three times as many patients taking Paxil CR achieved remission compared with placebo. In addition, the drop-out rate due to adverse events such as sexual dysfunction was low and comparable to the placebo level.

GlaxoSmithKline launched Paxil CR in the USA in April 2002. The FDA has already approved Paxil CR for the treatment of major depressive disorder, panic disorder and social anxiety and for the continuous treatment of PMDD. Paxil CR offers flexible dosing and is available in three different dosing strengths: 12.5 mg, 25 mg and 37.5 mg. In 2003, US sales of Paxil and Paxil CR were 1.2 billion (US$1.9 billion). SkyePharma receives ongoing royalty payments on GlaxoSmithKline's net sales of Paxil CR.