Bayer is developing vardenafil, an orally active phosphodiesterase (PDE) 5 inhibitor for the potential treatment of erectile dysfunction (ED) [314382]. NDAs were filed in September 2001 in the US and Mexico [423096], and vardenafil was submitted for Canadian approval in October 2001. As of November 2001, Bayer was expecting a response from the FDA in the second half of 2002 [429499]; the EMEA accepted a filing in January 2002, following a December 2001 submission [438163]. By October 2000, phase III trials were underway in Japan [384751] and by December 2001, a Japanese NDA had been filed; at the same time an application was filed in South Africa [426526], [433060]. At this time Japanese launch was expected in 2003 [434758]. By February 2001, Bayer was also investigating a nasal formulation of vardenafil for the potential treatment of erectile dysfunction [397608]. In November 2001, Bayer and GlaxoSmithKline signed a worldwide copromotion agreement for vardenafil, under which Bayer was to be responsible for all regulatory work required to obtain approval [429499]. In February 1999, Lehman Brothers predicted a 10% probability that vardenafil would reach the market, with launch in 2002. Peak Japanese sales of US$600 million were predicted for 2014 [319225]. In May 2000, Bayer predicted peak sales of Euro900 million [397137]. In July 2001, Lehman Brothers predicted a 75% chance that vardenafil would reach the market, and forecast peak sales of US $0.85 billion worldwide; the analyst also speculated that Bayer would seek a comarketing partner [414766].