Spain’s Almirall Prodesfarma has licensed European rights to GW Pharmaceuticals cannabis-based treatment for pain in multiple sclerosis patients, Sativex, from UK firm GW Pharmaceuticals.

The £46 million licensing deal reflects the improved prospects for Sativex (delta-9-tetrahydrocannabinol plus cannabidiol), which has had a long and winding road to approval but is now available in its first market, Canada, where it is sold by Bayer HealthCare. Bayer also has rights to the drug in the UK, but regulators there asked for an additional clinical trial last year, saying that more evidence of efficacy was needed to support approval. GW had originally hoped to win UK approval for Sativex in 2003.

The deal with Almirall – Spain’s biggest pharmaceutical company – gives GW a £12 million upfront fee, milestone payments for the completion of ongoing Phase III trials and a share of Sativex revenues.

Sativex is in Phase III trials for the treatment of MS symptoms (neuropathic pain and spasticity), neuropathic pain (peripheral and general) and cancer pain. Under the agreement GW is responsible for completing the development of Sativex in these three indications.

For GW, the deal brings a welcome cash injection and hikes the firm’s reserves up to £22 million. In June, the company reported a net loss in the first-half of £5.1 million, down from £6.9 million a year earlier.