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|Portola Pharmaceuticals Announces Topline Results from Phase 3 APEX Trial of Betrixaban for Prevention of Blood Clots in Acute Medically Ill Patients|
—Full Data Set to be Presented at
—Company to Hold Conference Call Today at 8:30 am ET—
APEX was designed to assess the relative risk (RR) in the composite endpoint of ultrasound-detected (asymptomatic) proximal deep venous thrombosis (DVT), symptomatic DVT, non-fatal pulmonary embolism (PE) or VTE-related death in high-risk acute medically ill patients treated with oral betrixaban for 35-47 days versus standard of care preventive anticoagulation with injectable enoxaparin dosed for 10±4 days. APEX enrolled 7,513 patients at more than 450 clinical sites worldwide.
The primary efficacy and safety analysis consisted of three pre-specified patient groups of increasing sample size: Cohort 1 - patients with elevated D-dimer levels (62 percent of the overall study population), Cohort 2 - patients with elevated D-dimer levels or age ≥75 years (91 percent of the overall study population), and the overall study population. By protocol definition, primary efficacy analysis testing of Cohort 1 was done first and required a p value of 0.05 or less in order to test Cohort 2, which in turn required a p value of 0.05 or less in order to test the overall study population.
Cohort 1 achieved a p value of 0.054, which did not meet the threshold. Cohort 2 and the overall study population achieved p values of 0.029 and 0.006, respectively. There was no statistical difference in major bleeding between the betrixaban and enoxaparin arms in any of these three patient groups. The number of fatal bleeds was balanced between the two arms, and the number of intracranial hemorrhages was numerically lower in the betrixaban arm. Positive net clinical benefit with betrixaban was observed.
“While we understand that the interpretation of these statistical and clinical results will be subject to discussions with regulatory agencies, we and the APEX Study academic leadership believe that the data in Cohort 1 were sufficiently strong to support a full assessment of Cohort 2 and the overall study population,” said
APEX is a groundbreaking study because it is the first thrombosis prevention trial to incorporate an enrichment strategy and statistical analysis plan derived from the
A summary of key topline efficacy and safety data follows:
*RR = relative risk calculated as the frequency of events with betrixaban divided by the frequency of events with enoxaparin
"VTE is a common disorder that contributes significantly to the burden of morbidity and mortality,” said
The APEX results will be presented at the
About VTE in Acute Medically Ill Patients
Conference Call Details