Two additional phase 3 studies of PCSK9 inhibitor deliver positive topline results

Two additional Phase 3 bococizumab trials, SPIRE-HR (High Risk) and SPIRE-FH (Familial Hypercholesterolemia), met their primary endpoint, demonstrating a significant reduction in the percent change from baseline in low-density lipoprotein cholesterol (LDL-C) at 12 weeks compared to placebo among adults at high and very high risk for cardiovascular events who were receiving a maximally tolerated dose of a highly effective statin.

SPIRE-HR and SPIRE-FH are the third and fourth of six SPIRE lipid-lowering Phase 3 studies to complete and show positive results. The two remaining SPIRE lipid-lowering studies are anticipated to complete later in 2016. Both SPIRE-HR and SPIRE-FH continued for 52 weeks to assess the longer-term efficacy and safety of bococizumab, an investigational Proprotein Convertase Subtilisin Kexin type 9 inhibitor (PCSK9i), in patients at high and very high risk for cardiovascular events.

The double-blind, randomized, placebo-controlled, parallel-group, multicenter, 52-week SPIRE-HR study evaluated the efficacy, safety and tolerability of bococizumab to lower LDL-C compared to placebo. The study included 711 adults with primary hyperlipidemia or mixed dyslipidemia at high and very high risk for cardiovascular events receiving a maximally tolerated dose of statin therapy whose LDL-C ≥70 mg/dL.

Patients in the SPIRE-HR study were considered at high and very high risk for a future cardiovascular event if they had a known history of cardiovascular disease, including coronary heart disease or atherosclerotic diseases, diabetes or chronic kidney disease.

The SPIRE-FH double-blind, randomized, placebo-controlled, parallel-group, multicenter, 52-week study evaluated the efficacy, safety and tolerability of bococizumab to lower LDL-C compared to placebo. The study included 370 adults with heterozygous familial hypercholesterolemia (HeFH) and at high and very high risk of cardiovascular events receiving a maximally tolerated dose of statin.

Patients with HeFH in the SPIRE-FH study were considered at high and very high risk for a future cardiovascular event if they had a known history of cardiovascular disease, diabetes or chronic kidney disease and an LDL-C ≥ 70 mg/dL or without a known history of cardiovascular disease, diabetes or chronic kidney disease with an LDL-C ≥100 mg/dL; patients were required to be on the highest locally approved dose of an eligible statin or on the maximally tolerated dose.

Bococizumab was generally safe and well tolerated in both trials. Overall, the proportion of patients experiencing adverse events was similar among treatment groups, with one exception of a higher incidence of injection site reactions seen for patients on bococizumab compared to those on placebo in both trials. The majority of reported injection site reactions were mild.

Complete study results from the SPIRE-HR and SPIRE-FH trials will be presented at a future scientific forum and will be part of the potential future regulatory filing for bococizumab.
 Press release Pfizer June 28, 2016