CSL Behring recently reported new results from its phase III clinical development program designed to evaluate Idelvion®. The findings were presented at the 58th Annual Meeting of the American Society of Hematology (ASH), held December 3-6, 2016, in San Diego, CA.

First approved by the US Food and Drug Administration in March, 2016, Idelvion® is indicated for on-demand control and prevention of bleeding episodes, management of bleeding following surgery and as a routine preventive (prophylaxis) measure to reduce the incidence of bleeding episodes in patients with hemophilia B, or factor IX (FIX) deficiency. The therapy combines or “fuses” recombinant FIX with albumin, a protein found in blood plasma that helps factor IX stay active in the bloodstream longer.

The purpose of the study was to pool data from CSL’s global PROLONG-9FP program and assess the relationship between estimated FIX levels and clinical bleeding risk in adult hemophilia B patients using Idelvion®, either prophylactically or on-demand. PROLONG-9FP included a total of 478 bleeding episodes in 57 adult patients with hemophilia B and FIX activity levels of less than 2%.

An examination of the study data showed that adult patients achieving sustained FIX activity levels above 5% or 10%, have approximately 80% lower risk of bleeding events over one year compared with patients having FIX levels below these thresholds. CSL investigators noted the significance of linking specific pharmacokinetic (the processing and duration of a drug’s effect in the body) targets with positive clinical outcomes. 

“This new analysis of Phase III IDELVION clinical trials shows a strong association between high and prolonged factor IX levels and efficacy of IDELVION in reducing bleeding risk in adult hemophilia B patients,” said John Roberts, PhD, Director of Clinical Pharmacology, CSL Behring, and lead investigator. “These findings provide additional clinical rationale for targeting and maintaining factor IX trough activity levels above 5 or 10 percent to optimize treatment outcomes, aligning with World Federation of Hemophilia clinical guidelines for the management of hemophilia.”

Source: PRNewswire, December 3, 2016