Beyond statins: LDL diversity
Beyond statins: PCSK9 inhibitors slash LDL; but not for all patients
No fewer than 20 companies are working on next-generation lipid-lowering agents intended to improve upon the benefits of statins, which lower LDL-C and reduce the risk of cardiovascular events but still leave millions of people above target LDL-C levels. While most are developing their compounds in similar settings - generally as add-ons to high-dose statins in patients not achieving LDL-C goals - emerging data suggest different mechanisms may turn out to be appropriate for different populations.
In March two mAbs that inhibit proprotein convertase subtilisin/kexin 9 made headlines with new clinical data.
As reported as the American College of Cardiology (ACC) meeting, REGN727 (SAR236553) from Regeneron Pharmaceuticals Inc. and Sanofi, and Amgen Inc.'s AMG 145 both showed some of the highest reductions in LDL-C seen in patients on high-dose statins.
The mAbs are at the front of at least eight programs targeting PCSK9 (see "PCSK9 Bandwagon," A10) .
"The PCSK9 pathway is in my opinion one of the most exciting in cardiovascular drug development and perhaps in all of drug development today," Amgen SVP of Global Development and CMO Michael Severino told BioCentury.
However, researchers who spoke to BioCentury noted other emerging therapeutic classes may be more appropriate for patients with mixed dyslipidemia and for patients with the most severe forms of hypercholesterolemia that are caused by deficiencies in LDL receptors.
Patients with severe disease caused by defective or missing LDL receptors are being targeted with inhibitors of microsomal triglyceride transfer protein (MTP) and apolipoprotein B-100 (APOB-100). This group includes patients with severe heterozygous and homozygous familial hypercholesterolemia (FH).
Anti-PCSK9 mAbs also may face competition from cholesteryl ester transfer protein (CETP) inhibitors. This class of small molecules is known more for raising HDL levels, but some compounds have been shown to significantly