Ambien

SkyePharma received $4m (€3m) on signing of the agreement, and hopes to receive a further $11m during the development phase and on product approval, and a further $20m in sales related payments.

The sleep-inducing product, currently known as SKP-1041, is a non-benzodiazepine hypnotic agent formulated using SkyePharma's patented GeoClock technology.

Although now bound by tight confidentiality restrictions following the Somnus deal, in-PharmaTechnologist.com has spoken to SkyePharma in the past about its GeoClock technology and its potential applications in delayed-release drug treatments.

The technology platform allows 'chronotherapy-focused' tablets, with the active drug loaded inside an outer tablet layer consisting of a mixture of hydrophobic wax and brittle material, which results in a pH-independent time lag before the drug is released at a predetermined rate.

The dry coating is designed to allow the timed delivery of both slow- and immediate release active cores, by releasing the inner tablet first, followed by the gradual disintegration of the surrounding outer shell.

The technology has already been applied in Lodotra (prednisone), a rheumatoid arthritis drug developed on behalf of Swiss firm Nitec Pharma, a spin-out company from Merck KGaA.

Back in June last year, managing director of SkyePharma's European operations Francesco Patalano, told in-PharmaTechnologist.com of the company's plans to apply the GeoClock technology to a sleep therapy.

He said that the product would be aimed at patients who have trouble maintaining continuity of sleep rather than problems dropping off to sleep in the first place, and that the company was aiming for the drug to be launched by 2011.

Speaking to Ken Cunningham, SkyePharma's chief operating officer, regarding the Somnus deal, in-PharmaTechnologist heard that this timescale could be altered depending on Somnus' decisions.

The product itself is still at the pre-clinical formulation stage, but Cunningham anticipated Phase I trials to begin in six to nine months' time.

SkyePharma is hoping to capture 10-15 per cent of the market with its delayed-release sleep therapeutic, which would work out at around $300m-£400m. SkyePharma itself is set to receive mid-high single digit royalties on sales of the drug, but it will still be a minor player in the company's portfolio compared to its asthma treatment Flutiform (fluticasone and formoterol) which the company foresees as a blockbuster billion dollar product.

Although non-benzodiazepine hypnotics are quite a well-known class of drugs and there are several products already on the market, Cunningham claims that SKP-1041 is novel in terms of what is currently available.

Other non-benzodiazepine sleep therapeutics out on the market include Sanofi-Aventis' Ambien (zolpidem) (which generated sales of over €2bn in 2006 with the company's two other zolpidem based products), King Pharmaceuticals' Sonata (zaleplon) and Sepracor's Lunesta (eszopiclone).