Enlicitide Decanoate (MK-0616, Lipfendra)
Enlicitide Decanoate (MK-0616, Lipfendra) is a novel, orally bioavailable macrocyclic peptide that acts as a PCSK9 inhibitor. It is designed to lower low-density lipoprotein cholesterol (LDL-C) by preventing PCSK9 from binding to LDL receptors, thereby increasing the clearance of LDL-C from the bloodstream. Clinical trials have shown it can reduce LDL-C by up to 60% when added to statin therapy.
01Dosing reference
Amount
20 mg
Frequency
Once daily
Cycle
Continuous daily use as prescribed
Reference figures, not a recommendationThese values reflect amounts described in the literature and vendor documentation this database indexes. Use the reconstitution calculator to convert them into syringe units.
02Mechanism of action
01
PCSK9 Binding
Enlicitide Decanoate binds with high affinity to the proprotein convertase subtilisin/kexin type 9 (PCSK9) protein in the bloodstream.
02
Receptor Interaction Blockade
By binding to PCSK9, it prevents PCSK9 from interacting with low-density lipoprotein (LDL) receptors on the surface of liver cells.
03
Increased LDL Clearance
With PCSK9 blocked, more LDL receptors remain available on the cell surface to bind and remove LDL cholesterol from the blood, leading to significantly lower circulating LDL-C levels.
03Human evidence
In the Phase 2b CORALreef Lipids trial, MK-0616 significantly reduced LDL-C by up to 60.9% compared to placebo at week 8 across various doses (6 mg to 30 mg daily).
Randomized, double-blind, placebo-controlled trial involving 381 adults with hypercholesterolemia and a broad spectrum of ASCVD risk, many of whom were on background statin therapy.
In the Phase 3 CORALreef Lipids trial, Lipfendra reduced LDL-C by 56% (up to 60% in post-hoc analysis) compared to placebo at week 24.
Randomized, double-blind, placebo-controlled study enrolling 2,904 patients with hypercholesterolemia and a history of or elevated risk for a major cardiovascular event.
In the Phase 3 CORALreef HeFH trial, Lipfendra reduced LDL-C by 59% compared to placebo at week 24 in patients with heterozygous familial hypercholesterolemia.
Trial involving 303 patients with heterozygous familial hypercholesterolemia. Diarrhea and dizziness were slightly more frequent in the treatment group.
04Preclinical evidence
MK-0616 displayed high affinity (Ki = 5pM) for PCSK9 in vitro and demonstrated sufficient safety and oral bioavailability in preclinical models to enable clinical advancement.
In vitro binding assays and preclinical pharmacokinetic/pharmacodynamic animal models.
The macrocyclic peptide design allowed MK-0616 to achieve the potency and selectivity of an antibody while maintaining a size and structure suitable for oral administration.
Structural biology and medicinal chemistry optimization using mRNA display technology.
05What is known vs. unknown
Reasonably established
- Enlicitide Decanoate is the first FDA-approved oral PCSK9 inhibitor, offering a once-daily pill alternative to injectable PCSK9 inhibitors.
- It effectively lowers LDL-C by approximately 55-60% in patients with hypercholesterolemia, including those on background statin therapy.
- The drug utilizes a novel macrocyclic peptide structure and a permeation enhancer (sodium caprate) to achieve oral bioavailability.
- It has shown efficacy in both general hypercholesterolemia populations and those with heterozygous familial hypercholesterolemia (HeFH).
Unknowns & limits
- While it significantly lowers LDL-C, data on its long-term impact on cardiovascular morbidity and mortality (e.g., reducing heart attacks and strokes) are still pending from the ongoing CORALreef Outcomes trial.
- The long-term safety profile and potential rare adverse events require further monitoring as the drug enters wider clinical use.
- Optimal positioning and cost-effectiveness compared to established injectable PCSK9 inhibitors and other novel lipid-lowering therapies remain to be fully determined.
06Safety & regulatory context
Regulatory statusEnlicitide Decanoate (Lipfendra) was approved by the FDA in July 2026 as an adjunct to diet and exercise to reduce LDL cholesterol in adults with hypercholesterolemia, including heterozygous familial hypercholesterolemia. In clinical trials, it was generally well-tolerated. The most common adverse reactions reported at higher frequencies than placebo included diarrhea and dizziness. No serious adverse events considered related to the treatment were reported in the Phase 2b trial. It is administered as a once-daily 20 mg oral tablet. As with any new medication, long-term safety and cardiovascular outcomes are being actively monitored in ongoing large-scale trials.
07Compared with Evolocumab (Repatha) or Alirocumab (Praluent)
Enlicitide Decanoate (MK-0616, Lipfendra) vs. Evolocumab (Repatha) or Alirocumab (Praluent)
Key difference
Enlicitide Decanoate is an orally administered macrocyclic peptide, whereas Evolocumab and Alirocumab are monoclonal antibodies that require subcutaneous injection.
When researchers discuss each
Researchers discuss Enlicitide when focusing on improving patient adherence and overcoming barriers associated with injectable therapies, while Evolocumab and Alirocumab are discussed in the context of established, long-term cardiovascular outcome benefits and their proven track record in clinical practice.
08Glossary
PCSK9
Proprotein convertase subtilisin/kexin type 9; a protein that regulates the number of LDL receptors on the surface of liver cells, thereby controlling the levels of LDL cholesterol in the blood.
Macrocyclic Peptide
A type of molecule consisting of a ring of amino acids. This structure can provide high binding affinity to targets (like antibodies) while being small enough to potentially be absorbed orally.
Hypercholesterolemia
A condition characterized by high levels of cholesterol in the blood, specifically high levels of low-density lipoprotein (LDL) cholesterol, which increases the risk of cardiovascular disease.
Heterozygous Familial Hypercholesterolemia (HeFH)
A genetic disorder inherited from one parent that causes extremely high levels of LDL cholesterol from birth, leading to an increased risk of early heart disease.
09Knowledge check
Q1What is the primary mechanism of action of Enlicitide Decanoate (MK-0616)?
Why: Enlicitide Decanoate is a PCSK9 inhibitor. It binds to the PCSK9 protein, blocking its interaction with LDL receptors, which allows more receptors to remain on the cell surface to clear LDL cholesterol from the blood.
Q2What is a key advantage of Enlicitide Decanoate compared to earlier PCSK9 inhibitors like Evolocumab?
Why: A major breakthrough with Enlicitide Decanoate (Lipfendra) is that it is the first FDA-approved oral PCSK9 inhibitor, offering a more convenient pill form compared to the injectable monoclonal antibodies previously available.
Q3Which documented limitation of the current evidence for Enlicitide Decanoate is stated in the dossier?
Why: The dossier explicitly notes that long-term safety and potential rare adverse events require further monitoring as the drug enters wider clinical use.
Q4According to the dossier, in which research context is Enlicitide Decanoate most likely to be emphasized compared with injectable PCSK9 monoclonal antibodies?
Why: The dossier says researchers discuss Enlicitide when focusing on improving adherence and overcoming barriers associated with injectable therapies, while Evolocumab/Alirocumab are discussed for their established long-term outcome benefits.
Q5Which statement about the regulatory and safety context of Enlicitide Decanoate is supported by the dossier?
Why: The dossier states FDA approval in July 2026 for adults with hypercholesterolemia as an adjunct to diet and exercise, and notes diarrhea and dizziness occurred more often than with placebo; it also notes no serious adverse events considered related were reported in the Phase 2b trial and that ongoing monitoring is occurring.
10Sources
- Other Merck’s MK-0616, an Investigational Oral PCSK9 Inhibitor, Significantly Reduced LDL-C in Patients with Hypercholesterolemia in Phase 2b Study
- Journal Phase 2b Randomized Trial of the Oral PCSK9 Inhibitor MK-0616
- Other FDA Approves Lipfendra to reduce LDL-C in Adults with Hypercholesterolemia
- Journal Orally Bioavailable Macrocyclic Peptide That Inhibits Binding of PCSK9 to the Low Density Lipoprotein Receptor
Research and educational use onlyNothing on this site is medical advice, a prescription, or a recommendation for human use. Compounds documented here are research chemicals. Consult a qualified clinician before making any health decision.