Two important milestones for Raptiva (efalizumab) – Merck Serono’s biological therapy for psoriasis – were reached this weekend.

Safety data from 10 years of clinical development and postmarketing experience were presented at the European Academy of Dermatology and Venereology congress, in Istanbul, Turkey. The data show that known adverse events have remained stable throughout the post-marketing period and confirm a favourable safety profile in the long-term treatment of moderate to severe chronic plaque psoriasis, said Andreas Katsambas of University of Athens in Greece.

“As of April 2008, some 50,000 patients have received Raptiva corresponding to more than 40,000 patient-years of exposure. Raptiva has one of the largest experimental databases in psoriasis,” he said. The EADV presentation comes hot on the heels of efficacy data published in this month’s British Journal of Dermatology.

Results from the three-year continuous dosing study (the longest for any biological therapy) show that Raptiva is effective for many patients with psoriasis; at three years 73% of responding patients achieved at least a 75% improvement in disease activity (Psoriasis Area and Severity Index [PASI 75]) and almost half (40%) of patients achieved and maintained a 90% improvement in symptoms (PASI 90).

Clinical benefit of Raptiva continuously improved over the first 18 months and was maintained during three years of continuous therapy. The safety profile was stable, with no new or no increase in common adverse events.

A spokesman for Merck Serono said the new long term safety and efficacy data were important and should provide a ‘tipping point’ for the market development of Raptiva, which is now available in more than 60 countries. He confirmed that a Phase IV multidisciplinary study is currently being planned which will investigate potential benefits of Raptiva on inflammation-mediated psoriasis co-morbidities.

Recent research has shown that people with psoriasis die ten years younger than people who do not suffer from the condition and are more likely to die from cardiovascular disease than the general population.