Merck’s Oral PCSK9 Candidate Cuts LDL by Up to 60%
Merck is reporting positive Phase 3 results for its oral PCSK9 inhibitor enlicitide, showing LDL-cholesterol reductions approaching 60% with a safety profile comparable to placebo. In the 2,900-patient study, adults with or at risk for atherosclerotic cardiovascular disease (ASCVD) taking once-daily enlicitide saw a 55.8% LDL-C reduction at week 24 versus placebo in the primary analysis, according to the company. A post-hoc reanalysis that removed five implausible baseline values showed a 59.7% drop.
LDL reductions remained durable through one year, Merck says, with declines of 47.6% (primary) and 52.4% (post-hoc). Enlicitide also reduced non-HDL-C, ApoB, and Lp(a), meeting all key secondary endpoints.
Safety results were largely indistinguishable from placebo, it says, with similar adverse event rates, serious events, and discontinuations (3.1% with enlicitide vs. 4.1% with placebo). Study adherence exceeded 97%, it adds.
Two-thirds of patients on enlicitide hit an aggressive combined goal: at least a 50% LDL reduction and an on-treatment LDL below 55 mg/dL at week 24. Only 1.2% of placebo patients met that bar.
“This drug delivered impressive LDL reductions with placebo-like safety,” a Merck release says. “Despite multiple available therapies, most ASCVD patients still don’t reach LDL targets. An oral PCSK9 inhibitor could be practice-changing.”
Enlicitide is described as a macrocyclic peptide designed to reproduce the biological mechanism of injectable PCSK9 monoclonal antibodies in a pill. If approved, it would become the first oral agent in the class.
Merck plans to submit data from CORALreef Lipids alongside two other pivotal programs — CORALreef HeFH and CORALreef AddOn — to regulators worldwide. The company is also running a 14,500-patient cardiovascular outcomes study, CORALreef Outcomes, which has completed enrollment.