Quick Comparison

CT-388Lemon Bottle
Half-LifeApproximately 168 hours (7 days), supporting once-weekly dosingComponents metabolized within hours; visible effects develop over 2-4 weeks
Typical DosagePhase 2 trials: doses up to 8 mg subcutaneous once weekly with stepwise escalation over 12-16 weeks. Phase 3 maintenance dosing being established. Higher and lower dose arms are being evaluated to balance weight loss against tolerability.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 (once weekly)Direct injection into subcutaneous fat (mesotherapy)
Research Papers2 papers1 papers
Categories

Mechanism of Action

CT-388

CT-388 is a once-weekly subcutaneous dual GLP-1/GIP receptor agonist, mechanistically similar to tirzepatide but with a distinct molecular structure designed for differentiated pharmacology. Activation of both receptors produces complementary metabolic effects: GLP-1 receptor agonism centrally suppresses appetite through hypothalamic and brainstem signalling, slows gastric emptying, and stimulates glucose-dependent insulin secretion from pancreatic beta cells, while GIP receptor agonism enhances beta-cell insulin response, modulates lipid handling in adipose tissue, and amplifies the central anorectic effect of GLP-1 through distinct hypothalamic neuronal circuits.

The molecule was engineered with a balanced potency profile across the two receptors and incorporates fatty acid acylation that enables strong albumin binding, extending half-life to approximately one week. This pharmacokinetic profile supports once-weekly subcutaneous dosing with stable plasma exposure across the dosing interval, which is associated with better gastrointestinal tolerability than less stable formulations that produce sharp peaks and troughs.

In the Phase 2 obesity trial of 469 participants, CT-388 produced up to 22.5% placebo-adjusted body weight reduction at 48 weeks at the highest dose. The weight-loss curve had not yet plateaued at the end of the trial, suggesting further reductions might be achievable with longer dosing. Roche acquired Carmot Therapeutics in late 2024 specifically to obtain CT-388, positioning it as their lead anti-obesity asset competing directly against tirzepatide and the next-generation Lilly and Novo Nordisk pipeline.

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

CT-388

Common

nausea, vomiting, diarrhea, constipation, decreased appetite, injection site reactions. Side-effect rates in Phase 2 were comparable to tirzepatide.

Serious

pancreatitis, gallstones, possible muscle mass loss, dehydration.

Rare

thyroid C-cell tumour class warning, severe allergic reactions. Long-term safety data not yet available.

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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