Swiss biotechnology group Serono has unveiled new long-term data underscoring the efficacy and long-term benefit of its Raptiva (efalizumab) in patients with psoriasis.

At a meeting in London yesterday the firm presented results of the CLEAR trial, which illustrated that 47.5% of patients showing significant disease improvement (as measured by the Psoriasis Area Severity Index) after taking Raptiva for 12 weeks achieved a 75% or greater improvement with extended therapy of 24 weeks.

In addition, more than 40% of patients with a Physician Global Assessment rating of ‘good’ after 12 weeks of treatment attained a rating of ‘excellent’ or ‘cleared’ with extended therapy.

Commenting on the findings, Prof Wolfram Sterry, director of the Clinic of Dermatology, Venereology and Allergology at the Charité in Berlin, said: “Biological treatments give us new hope of providing psoriasis patients with improved therapies that will be easier to manage. Raptiva has a favorable benefit-risk profile during continuous therapy in responders and should be considered as one of the best choice biological treatments for moderate-to-severe psoriasis.”

Dr Kim Papp from Probity Medical Research in Waterloo, Canada, explained to PharmaTimes News Online that these results are so significant as they mark the only long-term data available for any psoriasis therapy. Because of this, it is impossible draw any meaningful comparisons with other treatments, he said, but pointed out that some traditional therapies with similar efficacy are dogged with safety issues, such as the potential for renal damage at certain doses, thus providing Raptiva with an immediate advantage over its rivals.

But the drug does have some safety issue of its own, though somewhat less severe than those associated with other psoriasis agents. Recently, Serono’s US partner Genentech added a warning its label highlighting an increased risk of developing a certain type of anaemia, after two cases were observed in clinical trials and two further incidences reported after the drug obtained approval [[22/07/05g]]. Although the company says that a causal relationship has not been established, it cannot be excluded.

Raptiva is a humanized therapeutic antibody which blocks the action of T-cells responsible for psoriasis symptoms. The agent, representing one of Serono’s big hopes with a peak annual sales forecast of $250-$400 million, won the regulatory nod in Europe in September last year [[230904a]]. It has been available in the USA since 2003, where it is marketed by biotechnology giant Genentech and its partner Xoma [[28/10/03a]].