New analysis of Soliris in patients with PNH presented at ASH Annual Meeting

Independent investigators reported today that patients with paroxysmal nocturnal hemoglobinuria (PNH) who were treated long-term with Soliris^® (eculizumab) achieved survival comparable to that of an age- and gender-matched normal population. Findings from this investigator-led analysis were reported in an oral presentation today at the 52^nd American Society of Hematology (ASH) Annual Meeting and Exposition in Orlando. Soliris is a first-in-class terminal complement inhibitor developed by Alexion Pharmaceuticals, Inc. (Nasdaq: ALXN).

“In these patients, we observed far fewer thromboses than expected during long-term treatment with Soliris compared with the thromboses seen pre-treatment. This is important because thromboses are common and deadly complications of PNH”

PNH is an ultra-rare, life-threatening blood disorder in which uncontrolled activation of the complement system causes the chronic destruction of red blood cells (hemolysis). Historically, up to 35% of patients with PNH die within five years of diagnosis due to serious clinical outcomes including thromboembolism (TE) and chronic kidney disease (CKD).

Investigator-Led Analysis Showed Sustained Efficacy and Improved Survival with Soliris

In the analysis presented today titled, "Long Term Treatment with Eculizumab In Paroxysmal Nocturnal Hemoglobinuria (PNH): Sustained Efficacy and Improved Survival," researchers from St. James's University Hospital in Leeds, UK, compared data from 79 patients with PNH treated with Soliris for up to eight years (mean 39 months) with an age- and gender-matched normal population based on data from the UK Office of National Statistics. Nearly half of the PNH patients in this analysis participated in the Soliris PNH clinical trials.

The analysis reported in the published abstract demonstrated comparable survival between patients with PNH treated with Soliris and the normal population. There were fewer thrombotic events among patients with PNH following Soliris therapy, with 34 thrombotic episodes occurring in 21 patients prior to treatment, and only two thromboses occurring in those same patients after the start of Soliris treatment. Of 64 patients treated with Soliris for at least one year, 66% became transfusion-independent for more than 12 months, and the remaining 34% showed a significant 41% reduction in the mean units transfused>

"In these patients, we observed far fewer thromboses than expected during long-term treatment with Soliris compared with the thromboses seen pre-treatment. This is important because thromboses are common and deadly complications of PNH," noted Peter Hillmen, M.D., Ph.D., consultant hematologist at the Leeds Teaching Hospitals NHS Trust and lead study investigator. "The comparable survival rates observed between patients with PNH treated with Soliris in this analysis and the general population in the UK is very important for patients with a disease in which life expectancy is reduced substantially. This finding underlines the key role of uncontrolled complement activity in the most important adverse consequences of PNH and that protecting PNH cells from this uncontrolled attack is critical to the effective targeted therapy of the disease."

Clinical Study Demonstrates Long-Term Safety and Efficacy of Soliris

In a poster presentation today titled, "Long Term Safety and Efficacy of Sustained Eculizumab Treatment in Patients with Paroxysmal Nocturnal Hemoglobinuria (PNH)," researchers reported clinical findings from a multi-center study that included all 195 patients from the pilot and Phase 3 clinical trials of Soliris, as well as from subsequent extension studies. Patients were treated with Soliris for up to 5.5 years (median 29 months). Efficacy findings were reported for patients at 36 months of Soliris treatment.

Within one week, hemolysis, as assessed by levels of LDH, was reduced in 100% of patients treated with Soliris and was sustained throughout the treatment period (p<0.000001). Overall survival was 97.6% (95% CI 93.7-99.1) at 36 months. In addition, TE events were reduced by 81%, from 52 pre-treatment events to 10 events during Soliris therapy using matched time analysis (P<0.0005). The prevalence of CKD was reduced from 69% of patients at baseline to 31%>

Soliris was well-tolerated during the treatment period. The most common adverse events reported included headache (55%), nasopharyngitis (50%), upper respiratory tract infection (41%), diarrhea (35%), and nausea (32%). There were two cases of meningococcal sepsis, which were both successfully treated without sequelae.

"These long-term data show that the compelling clinical benefits and safety profile of Soliris seen in shorter-term studies were sustained over 36 months," said lead investigator Robert A. Brodsky, M.D., director of the Division of Hematology and professor of medicine and oncology at Johns Hopkins Medicine in Baltimore. "Soliris is the first and only medication approved for the treatment of patients with PNH, and we now have evidence that this therapy can provide long-term reduction in hemolysis with documented safety for patients with this life-threatening condition."