Quick Comparison

AT7687Lemon Bottle
Half-LifeApproximately 7-10 days, supporting once-weekly dosingComponents metabolized within hours; visible effects develop over 2-4 weeks
Typical DosagePhase 1 first-in-human trial: ascending single and multiple subcutaneous doses. Dose ranges and Phase 2 protocols still being established. The mechanism does not require dose escalation for tolerability the way GLP-1 drugs do — appetite is not the primary target.Localized injection: 1-5 vials injected directly into subcutaneous fat per session, depending on treatment area. Sessions spaced 1-2 weeks apart, 3-5 sessions recommended per treatment area. Administered by trained practitioners only.
AdministrationSubcutaneous injection (likely once weekly based on pharmacokinetics)Direct injection into subcutaneous fat (mesotherapy)
Research Papers1 papers1 papers
Categories

Mechanism of Action

AT7687

AT7687 is a long-acting GIP receptor antagonist designed to reduce fat storage rather than suppress appetite — a fundamentally different mechanism from every other obesity drug currently on the market or in late-stage development. The rationale is grounded in human genetics: loss-of-function variants in the GIP receptor are associated with lower body mass index and reduced cardiometabolic risk, suggesting that pharmacologically blocking GIP signalling should reproduce these protective effects.

GIP (glucose-dependent insulinotropic polypeptide) normally functions as a fat-storage signal — released from intestinal K-cells in response to food intake, it instructs adipose tissue to take up and store circulating fatty acids. By blocking the GIP receptor specifically on adipocytes, AT7687 prevents this fat-storage signal from being transmitted, leading to reduced lipid uptake into fat cells and a metabolic shift favouring fat oxidation in muscle and liver. Because the mechanism does not depend on suppressing hunger or slowing gastric emptying, the gastrointestinal side effects that limit GLP-1 drug tolerability are largely absent.

This mechanism is the conceptual mirror of MariTide (which combines GLP-1 agonism with GIP antagonism in a single molecule) — AT7687 isolates the GIP-antagonist component to test whether it can produce meaningful weight loss alone or in future combination with GLP-1 agonists. Antag Therapeutics' first-in-human Phase 1 results in 2026 showed acceptable tolerability with mild GI symptoms, plus reductions in LDL cholesterol and resting heart rate — early signals consistent with the predicted cardiometabolic benefit profile. Phase 2 trials are expected to define the magnitude of weight loss achievable in obese patients.

Lemon Bottle

Lemon Bottle uses a combination of three active ingredients that work through complementary mechanisms to achieve localized fat cell disruption. The primary active component is lecithin (phosphatidylcholine), an amphiphilic phospholipid that, when injected directly into subcutaneous fat, acts as a detergent on adipocyte cell membranes. Phosphatidylcholine inserts into the lipid bilayer of fat cells, destabilizing membrane integrity and causing cell lysis — physically rupturing fat cells and releasing their stored triglyceride contents into the surrounding interstitial space.

Bromelain, a proteolytic enzyme complex derived from pineapple stems, serves as the second active component. Once fat cells are ruptured, bromelain helps break down the released cellular debris and protein structures, facilitating the body's inflammatory cleanup response. It also has anti-inflammatory properties that may help moderate the significant tissue swelling that occurs after injection lipolysis. The third component, riboflavin (vitamin B2), is a precursor to FAD (flavin adenine dinucleotide), a coenzyme essential for mitochondrial fatty acid beta-oxidation.

The overall process relies on the body's natural inflammatory and metabolic clearance systems — macrophages phagocytose cellular debris, released fatty acids are transported to the liver for processing, and the treated area gradually reduces in volume over 2-4 weeks. It is important to note that this is a localized cosmetic treatment, not a systemic weight loss solution, and the scientific evidence supporting its efficacy is primarily anecdotal rather than derived from controlled clinical trials.

Risks & Safety

AT7687

Common

mild gastrointestinal symptoms (notably milder than GLP-1 agonists in early data), injection site reactions.

Serious

long-term effects on bone health unknown — GIP signalling has roles in bone metabolism.

Rare

limited human safety data so far. Cardiovascular profile in Phase 1 included reductions in LDL cholesterol and resting heart rate, suggesting a metabolically favourable safety signal.

Lemon Bottle

Common

swelling, bruising, redness, and tenderness at injection site lasting several days.

Serious

tissue death if injected into the wrong area, uneven fat reduction, lumpy or irregular skin surface.

Rare

infection, allergic reaction, persistent hard lumps under skin.

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