Retatrutide 20mg+Tirzepatide 40mg

• No health or weight-management benefit has been established for the blend
• Separate trials show pharmacologic activity for each single agent, but both engage GIP and GLP-1 receptors and no evidence demonstrates that combining them improves outcomes versus either agent alone
• The scientifically supportable uses of this material are limited to properly controlled analytical, formulation, stability or exploratory in vitro research.

CAS

Confirm per batch COA

Formula

Not applicable — mixture or multi-component material

Molecular weight

Component-specific; no single molecular weight

Appearance

Lyophilized material; confirm released-lot appearance on the COA

Purity

Per batch COA

Storage

Store and ship according to the batch COA and validated stability data for this exact two-component formulation. Single-agent labels do not establish stability for a mixed lyophilizate or reconstituted blend. Require component-specific recovery, degradation and ratio-stability data across temperature, light, container, diluent and freeze-thaw conditions.

MOQ

1 kit (10 vials) per SKU

Lead time

Confirmed with quote

This catalogue item is a vendor-defined physical mixture labelled as 20 mg retatrutide plus 40 mg tirzepatide. It is not an Eli Lilly product, an FDA-approved fixed-dose combination or a formulation evaluated in a qualifying clinical or preclinical co-administration study identified in this review. Retatrutide is an investigational GIP/GLP-1/glucagon receptor agonist; tirzepatide is an approved GIP/GLP-1 receptor agonist only in specific regulated drug products. Evidence for either component alone cannot be used to claim additive efficacy, acceptable exposure or safety for this mixture. FDA currently states that retatrutide cannot be used in compounding under U.S. federal law and has not been found safe and effective for any condition.

• No clinical indication applies to this mixture
• Suitable research questions include component-specific LC-MS quantitation, blend homogeneity, ratio recovery, forced-degradation and compatibility studies, and carefully controlled in vitro receptor assays
• Obesity, diabetes, liver-fat and cardiovascular results belong to the individual agents and are not indications for the blend.

Retatrutide and tirzepatide are distinct long-acting lipidated peptides. Retatrutide activates GIP, GLP-1 and glucagon receptors; tirzepatide activates GIP and GLP-1 receptors. A mixture therefore contains overlapping GIPR/GLP-1R agonism plus retatrutide's GCGR activity, but receptor occupancy, bias, desensitization, protein binding, exposure and tolerability for co-administration have not been established. Mechanistic overlap is not evidence of synergy.

• No combination-specific clinical safety, pharmacokinetic, toxicology, immunogenicity or dose-escalation data exist
• Individual-agent adverse-event and warning information cannot quantify risk for the mixture
• The FDA boxed warning and contraindications apply to approved tirzepatide products; retatrutide has no FDA-approved label, and FDA currently states that it cannot be used in compounding under U.S. federal law
• This material is for laboratory research only and not for human or veterinary administration.

Interactions reported in the literature

• The current FDA Zepbound label does not recommend tirzepatide coadministration with other tirzepatide-containing products or any GLP-1 receptor agonist
• Retatrutide is an investigational GLP-1/GIP/glucagon agonist, so this limitation is directly relevant to the proposed pairing
• No validated compatibility, synergy, mitigation peptide or additional stacking protocol exists for the mixture.

Laboratory: Manufacturer's QC laboratoryTests: HPLC purity · MS identity · endotoxin · fill amount

• 60 mg

Previews are blurred on purpose so the documents cannot be reused; third-party reports show their first page only. Sales sends the clear full version for the product and strength you ask about.

Independent test fails? Full refund.

On every batch COA: HPLC purity · MS identity · endotoxin · fill amount · Verify LyoPep

Ask for the current packet, not a generic certificate

• A visual check cannot verify a two-peptide blend
• Require independent identity confirmation for both components by high-resolution intact mass and sequence-confirming MS/MS or peptide mapping; orthogonal chromatographic separation; component-specific net content showing the claimed 20:40 mg amount and 1:2 ratio; blend homogeneity and vial-to-vial uniformity; impurity and degradant profiles for each peptide; counterions, water, residual solvents, endotoxin or microbiological claims where applicable; and stability data demonstrating ratio retention
• A single aggregate HPLC purity percentage is not sufficient.

Store and ship according to the batch COA and validated stability data for this exact two-component formulation. Single-agent labels do not establish stability for a mixed lyophilizate or reconstituted blend. Require component-specific recovery, degradation and ratio-stability data across temperature, light, container, diluent and freeze-thaw conditions.

State the destination and timing so receipt can be planned, then move the material into its stated storage condition on arrival.

• The 2023 NEJM retatrutide phase 2 trial, 2024 Nature Medicine liver-fat substudy and Lilly’s May 2026 TRIUMPH-1 release describe retatrutide alone. SURMOUNT-1, tirzepatide safety reviews and the current FDA Zepbound label describe tirzepatide alone. ClinicalTrials.gov NCT06662383 compares retatrutide with tirzepatide in separate arms; it does not co-administer them. FDA’s current unapproved-GLP-1 information states that retatrutide cannot be used in compounding under U.S. federal law. No qualifying source reviewed evaluates this 20 mg plus 40 mg mixture.

1. 01

   Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial

   New England Journal of Medicine · 2023 · peer-reviewed original research (randomized, double-blind, placebo-controlled phase 2 trial)

   Open source
2. 02

   Triple Agonism Based Therapies for Obesity

   Current Cardiovascular Risk Reports · 2025 · peer-reviewed narrative review

   Open source
3. 03

   Triple hormone receptor agonist retatrutide for metabolic dysfunction-associated steatotic liver disease: a randomized phase 2a trial

   Nature Medicine · 2024 · peer-reviewed original research (randomized, double-blind, placebo-controlled phase 2a substudy)

   Open source
4. 04

   Tirzepatide Once Weekly for the Treatment of Obesity

   New England Journal of Medicine · 2022 · peer-reviewed original research (randomized, double-blind, placebo-controlled phase 3 trial)

   Open source
5. 05

   A systematic review of the safety of tirzepatide-a new dual GLP1 and GIP agonist - is its safety profile acceptable?

   Frontiers in Endocrinology · 2023 · peer-reviewed systematic review

   Open source
6. 06

   Lilly's triple agonist, retatrutide, delivered powerful weight loss in pivotal Phase 3 obesity trial

   Eli Lilly and Company (Investor Relations) · 2026 · company press release / official investor communication

   Open source
7. 07

   FDA Approves New Medication for Chronic Weight Management

   U.S. Food and Drug Administration · 2023 · regulatory document / official government press announcement

   Open source

• How to read a peptide COA without confusing purity, identity and content
• Peptide purity versus peptide content: a buyer’s method map
• Questions to ask a research peptide supplier before the first purchase order