Side-by-side · Research reference

LiraglutidevsMK-677

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

AFDA-ApprovedVerified14/45 cited

BPhase 2Reviewed13/45 cited

Liraglutide

Daily GLP-1 RA · FDA-Approved

0.6–3.0 mgDaily doseSAXENDA (liraglutide) injectio 2014

5–10%Body-weight ↓SAXENDA (liraglutide) injectio 2014

~13 hrHalf-lifeSAXENDA (liraglutide) injectio 2014

SQ · Abdomen / thigh / arm · Once daily

MK-677

Oral GHS · Ibutamoren

10–25 mgDaily dose (oral)Nass 2008

Phase 2Evidence levelMurphy 1998 Nass 2008

~24 hrHalf-lifeNass 2008

Oral capsule · 1×/day

01Mechanism of Action

Parameter

Liraglutide

MK-677

Primary target

GLP-1 receptor (GLP-1R)SAXENDA (liraglutide) injectio 2014

Ghrelin receptor (GHS-R1a)Murphy 1998

Pathway

GLP-1R agonism → ↑glucose-dependent insulin, ↓glucagon, ↓gastric emptying, ↓appetiteSAXENDA (liraglutide) injectio 2014 Marso 2016

GHS-R1a → Gαq → Ca²⁺ → sustained GH pulses across 24 hrNass 2008

Downstream effect

Glycemic improvement, modest body-weight reduction, cardiovascular event reduction in high-risk T2DMarso 2016

Sustained GH + IGF-1 elevation; appetite stimulation; lean mass preservationNass 2008

Feedback intact?

Glucose-dependent insulin release preserves physiological feedback

Pulsatile pattern preserved despite long half-lifeMurphy 1998

Origin

Modified GLP-1(7-37) with Lys26 substitution (Arg34) and C-16 palmitoyl-glutamate acylation for albumin bindingSAXENDA (liraglutide) injectio 2014

Non-peptide spiroindane-piperidine small molecule designed at MerckMurphy 1998

Antibody development

—

02Dosage Protocols

Parameter

Liraglutide

MK-677

Standard dose (T2D, Victoza)

1.2–1.8 mg / daySAXENDA (liraglutide) injectio 2014

—

Standard dose (weight, Saxenda)

3.0 mg / day (after 5-week titration)SAXENDA (liraglutide) injectio 2014

—

Frequency

Once daily, same time each day

Once daily, oral

Titration schedule

0.6 → 1.2 → 1.8 → 2.4 → 3.0 mg over 5 weeks

Mitigates GI side effects.

—

Evidence basis

FDA-approved · Phase 3 RCTs (LEADER, SCALE)Marso 2016 SAXENDA (liraglutide) injectio 2014

Phase 2 trials (Nass 2008, Murphy 1998)Nass 2008 Murphy 1998

Duration

Indefinite for chronic indication

8–16 weeks per cycle (off-cycle to reset receptor sensitivity)

Reconstitution

Pre-filled commercial pen (no reconstitution)

Oral, no reconstitution

Timing

Any time of day; consistent

Pre-sleep preferred for natural GH pulse alignment

Half-life

~13 hrSAXENDA (liraglutide) injectio 2014

~24 hrNass 2008

Once-daily dosing covers 24 hours.

Standard dose

—

10–25 mg / day oralNass 2008

25 mg used in Nass 2008 elderly trial; 10–15 mg common community dose.

Lower / starter dose

—

5 mg / day

04Side Effects & Safety

Parameter

Liraglutide

MK-677

GI symptoms

Nausea, vomiting, diarrhea (very common during titration)SAXENDA (liraglutide) injectio 2014

—

Pancreatitis risk

Rare; discontinue if suspected

—

Thyroid C-cell tumours

Boxed warning — contraindicated in MEN2 / MTC historySAXENDA (liraglutide) injectio 2014

—

Hypoglycemia

Low risk as monotherapy; elevated with sulfonylureas / insulin

—

Heart rate

Modest ↑ resting HR (~2-3 bpm)

—

Cardiovascular benefit

↓ MACE in high-risk T2D (LEADER trial)Marso 2016

—

Pregnancy / OB

Contraindicated

Avoid

Increased appetite

—

Strong appetite increase via ghrelin agonism

Water retention

—

Mild edema, paresthesias

Glucose tolerance

—

↑ HbA1c +0.3–0.5% in 2-yr elderly trialNass 2008

IGF-1 elevation

—

+50–100% sustainedNass 2008

Cancer risk

—

Contraindicated in active malignancy (GH/IGF-1 axis)

Cardiovascular

—

No clear adverse signal in trials; congestive heart failure caution

Drowsiness

—

Common, especially during initial weeks

Absolute Contraindications

Liraglutide

·MTC personal or family history; MEN2
·Pregnancy / breastfeeding
·Hypersensitivity to liraglutide

MK-677

·Active malignancy
·Pregnancy / breastfeeding
·Disrupted hypothalamic-pituitary axis
·Congestive heart failure (caution)

Relative Contraindications

Liraglutide

·Severe gastroparesis
·History of pancreatitis
·Severe gastrointestinal disease

MK-677

·Untreated diabetes
·Pre-diabetes
·Severe insulin resistance

05Administration Protocol

Parameter

Liraglutide

MK-677

1. Reconstitution / device

Commercial pre-filled pen, no reconstitution required.

Capsule or oral solution. No injection.

2. Injection site

SQ — abdomen, thigh, or upper arm. Rotate sites.

Oral. Take with or without food.

3. Timing

Once daily, same time each day. Take with or without food.

Pre-sleep preferred — aligns with natural GH pulse.

4. Storage

Refrigerate 2–8 °C unopened; room temp ≤30 °C up to 30 days after first use.

Capsule: room temp ≤25 °C, dry place.

5. Needle

Pen-supplied 32G needle.

Monitor HbA1c every 8–12 weeks during chronic use.