Biogen Idec and partner PDL BioPharma say that an ongoing Phase II trial of their humanised monoclonal antibody daclizumab has met its primary endpoint in relapsing multiple sclerosis.

The companies said 230 patients being treated with interferon beta received daclizumab 2mg/kg subcutaneously every two weeks and the data showed a significant reduction in the number of new or enlarged gadolinium-contrast-enhancing lesions at week 24. They now plan to initiate a Phase II monotherapy trial of daclizumab.

Biogen and PDL entered into a deal in 2005 to co-develop and commercialise daclizumab and the firms are also co-developing volociximab (also known as M200), an antibody in Phase II development for the treatment of various solid tumours. PDL is also separately working with Roche for the clinical development and potential commercialization of daclizumab as a treatment for asthma and transplant maintenance and the Swiss firm currently sells the drug under the name Zenapax for acute organ rejection in patients receiving renal transplants.