Pfizer drug helps patients with hard-to-treat cholesterol

Pfizer has announced results from a Phase 2b study of bococizumab, its candidate for patients with hard-to-treat raised cholesterol.

Bococizumab (RN316) is one of a new class of drugs which inhibit PCSK9, a protein that keeps LDL ('bad' cholesterol) levels elevated in the bloodstream.

Pfizer is in competition with rivals to develop the best in class, with the race to become first to market closely run. Rival molecules are being developed by Amgen and by a partnership between Sanofi and Regeneron. The partners released late last year promising phase III data showing their drug alirocumab worked well as a monotherapy – lowering LDL cholesterol three times more than Merck's Zetia (ezetimibe)

The bococizumab study met its primary endpoint in all doses of the the dose-ranging study, showing that it significantly reduced LDL cholesterol from baseline compared to placebo in adults with high cholesterol also taking statin therapy.

Pfizer is famous for having marketed Lipitor, the cholesterol lowering statin drug that became the world's biggest selling drug before going off patent in 2011. The firm is now looking to pioneer a next generation of cholesterol treatments, although PCSK9 drugs won't be prescribed as routinely as statins, but will instead be reserved for patients with the most hard to treat cholesterol problems.

Pfizer says elevated LDL-C is recognised as a major risk factor for cardiovascular disease, the number one cause of death worldwide despite the widespread availability of statin therapy.

"I am hopeful that bococizumab, as a member of the PCSK9 class, will play an important role in understanding and addressing the unmet need for patients at high risk for cardiovascular events. The Phase 3 CV outcome studies for this class of medicine will be the most critical in defining future clinical practice," said Christie M Ballantyne, Chief of the Section of Cardiology and Cardiolvascular Research from Baylor College of Medicine.

Large outcomes trials

Pfizer's Phase 3 programme includes two cardiovascular outcome studies in populations at high risk from cardiovascular events.

The bococizumab Phase 3 programme consists of two cardiovascular outcome studies as well as multiple lipid-lowering studies in more than 22,000 patients. One of the two CV outcome studies, SPIRE-1, will assess whether lowering LDL-C to levels well below current guideline-recommended targets will lead to further reduction in cardiovascular events. This study includes a high-risk patient population with baseline levels of LDL-C ranging from 70 to 100 mg/dL.

The second study, SPIRE-2, will evaluate bococizumab in a range of high-risk patients who have not achieved LDL levels lower than 100 mg/dL despite the use of high-dose statins or who are partially or completely statin intolerant. The Phase 3 programme will evaluate the efficacy and safety of 150 mg twice monthly as a starting dose.

Pfizer's data follows close behind the release of phase 3 data from Amgen for its drug evolocumab, but the company did not release detailed results.

Links

Amgen cholesterol drug hits trial target