--- title: "ASC39 | PepTracker Pro" url: https://peptrackerpro.com/peptides/asc39 description: "ASC39 is Ascletis Pharma's investigational once-daily oral small-molecule amylin-selective amylin receptor agonist for obesity. In head-to-head preclinical assays it matched Eli Lilly's injectable peptide eloralintide on amylin-receptor potency, selectivity over the calcitonin receptor, and weight loss in diet-induced obese rats. Ascletis plans to file a U.S. FDA IND for ASC39 - and for a fixed-dose combination with its oral GLP-1 agonist ASC30 - in the third quarter of 2026." lang: en --- Skip to main content **Educational information only.** This site does not provide medical advice. Read full disclaimer (https://peptrackerpro.com/disclaimer) **Research-only content.** This page is for educational purposes and does not constitute medical advice. Read full disclaimer → (https://peptrackerpro.com/research-disclaimer) # ASC39 Low Evidence ASC39 is Ascletis Pharma's investigational once-daily oral small-molecule amylin-selective amylin receptor agonist for obesity. In head-to-head preclinical assays it matched Eli Lilly's injectable peptide eloralintide on amylin-receptor potency, selectivity over the calcitonin receptor, and weight loss in diet-induced obese rats. Ascletis plans to file a U.S. FDA IND for ASC39 - and for a fixed-dose combination with its oral GLP-1 agonist ASC30 - in the third quarter of 2026. Aliases Ascletis ASC39 +4 more Evidence Low Evidence Last Updated 2026-07-30 Reading Time 5 min ## What It Is ASC39 is an oral, once-daily small-molecule agonist of the amylin receptor being developed by Ascletis Pharma (HKEX: 1672) for obesity. Amylin is a pancreatic hormone co-secreted with insulin that promotes satiety, slows gastric emptying, and - unlike some appetite pathways - tends to preserve lean mass during weight loss, making it one of the most clinically validated non-GLP-1 targets in obesity medicine. Amylin signals through the calcitonin receptor (CTR) and through the amylin receptors AMY1/AMY2/AMY3 (each the calcitonin receptor paired with a receptor-activity-modifying protein, RAMP1/2/3). The current amylin front-runners are almost all peptides given by subcutaneous injection - cagrilintide, petrelintide and Eli Lilly's selective agonist eloralintide - so a potent oral small molecule that reproduces their pharmacology would be a meaningful differentiator, both as a standalone pill and as a combination partner. ASC39 is designed to be that molecule: an 'eloralintide-like' amylin-selective agonist delivered as a once-daily tablet. Ascletis has reported head-to-head preclinical data that put ASC39 essentially on par with eloralintide. In cyclic-AMP (cAMP) activation assays, ASC39's half-maximal effective concentration (EC50) at the human amylin 1 receptor was 21.4 pM versus 21.2 pM for eloralintide, while its EC50 at the human calcitonin receptor was 846.1 pM versus 1,350.8 pM for eloralintide - indicating comparable potency at the amylin receptor and similar (indeed marginally greater) selectivity away from the calcitonin receptor, which is the receptor most linked to amylin-associated nausea and food aversion. In diet-induced obese (DIO) rats, oral ASC39 produced significant placebo-adjusted weight loss of 6.6%, compared with 5.6% for eloralintide in the same study. Ascletis presented these findings at the American Diabetes Association (ADA) 2026 Scientific Sessions (New Orleans, June 5-8, 2026) alongside clinical data for its oral GLP-1 agonist ASC30 and preclinical data for its triple agonist ASC37. Ascletis selected ASC39 as a clinical development candidate in early 2026 and expects to submit a U.S. FDA Investigational New Drug (IND) application for ASC39 oral tablets in obesity in the third quarter of 2026. In parallel, the company selected a fixed-dose combination, ASC30_39 FDC, that pairs ASC39 with ASC30 (a Phase III-ready once-daily oral small-molecule GLP-1 receptor agonist reported to cause about half the vomiting of orforglipron under weekly titration) into a single once-daily tablet; in a head-to-head dog study the combination tablet showed excellent oral bioavailability, high drug exposure and a half-life of up to 12 hours, along with good compatibility, room-temperature stability and a small pill size. An IND for the ASC30_39 FDC is likewise planned for the third quarter of 2026. ASC39 reflects two converging 2026 themes in obesity drug development: the 'amylin renaissance,' in which amylin-based, lean-mass-sparing mechanisms are pursued as the next pillar beyond GLP-1, and the race to move these mechanisms from weekly injections into convenient oral small molecules. Also known as: Ascletis ASC39, ASC-39, oral amylin receptor agonist ASC39, amylin-selective small molecule agonist, ASC30_39 FDC component ## Regulatory Status Investigational Preclinical / IND-enabling as of mid-2026. Selected as a clinical development candidate in early 2026; Ascletis plans to submit a U.S. FDA IND for ASC39 oral tablets (and for the ASC30_39 fixed-dose combination) for obesity in Q3 2026. No IND cleared and no human trials begun as of July 2026. Not approved in any jurisdiction. Effective: 2026 View FDA Source (https://www.prnewswire.com/news-releases/oral-small-molecule-amylin-receptor-agonist-asc39-demonstrated-eloralintide-like-amylin-selectivity-and-efficacy-in-preclinical-models-302715843.html) ## Why Researchers Study It ASC39 is watched because it tests whether the amylin pathway - one of the most validated non-GLP-1 obesity mechanisms, and one prized for sparing lean mass - can be captured in a convenient oral small molecule rather than a weekly injection. Ascletis has reported preclinical potency, calcitonin-receptor selectivity and weight loss essentially matching Eli Lilly's injectable peptide eloralintide, so ASC39 serves as a proof-of-concept that oral chemistry can reproduce best-in-class amylin peptide pharmacology. It is also a building block for combination therapy: paired with the oral GLP-1 agonist ASC30 in the ASC30_39 fixed-dose tablet, it could enable an all-oral GLP-1-plus-amylin regimen, the oral analog of the injectable CagriSema/MariTide combination strategy. Finally, it is a leading example of the 2026 'amylin renaissance' and the broader push to convert injectable obesity biology into once-daily pills. ## Proposed Mechanisms - Agonizes the amylin receptor (calcitonin receptor paired with RAMP proteins) to promote satiety, slow gastric emptying and reduce food intake - Amylin-selective: comparable potency at the human amylin 1 receptor (EC50 ~21.4 pM) with substantially weaker activity at the human calcitonin receptor (EC50 ~846 pM), the receptor linked to amylin-related nausea and aversion - Aims to preserve lean mass during weight loss, a hallmark attributed to amylin-pathway signaling - Formulated as a once-daily oral small-molecule tablet rather than a subcutaneous peptide injection - Designed as a combination partner with the oral GLP-1 agonist ASC30 (ASC30_39 fixed-dose combination) for additive weight loss in a single pill ## Evidence Snapshot Low Evidence Low Medium High | Study Type | Model | Outcome | Link | | --- | --- | --- | --- | | Preclinical (in vitro) | Human amylin 1 receptor and calcitonin receptor cAMP activation assays (head-to-head vs eloralintide) | ASC39 EC50 at human amylin 1 receptor 21.4 pM vs 21.2 pM for eloralintide; EC50 at human calcitonin receptor 846.1 pM vs 1,350.8 pM for eloralintide - comparable amylin-receptor potency and similar/greater selectivity over the calcitonin receptor | Source: https://www.prnewswire.com/news-releases/oral-small-molecule-amylin-receptor-agonist-asc39-demonstrated-eloralintide-like-amylin-selectivity-and-efficacy-in-preclinical-models-302715843.html | | Preclinical (in vivo) | Diet-induced obese (DIO) rats, oral dosing (head-to-head vs eloralintide) | Significant placebo-adjusted weight loss of 6.6% for ASC39 vs 5.6% for eloralintide | Source: https://www.prnewswire.com/news-releases/ascletis-reinforces-its-differentiated-obesity-portfolio-at-american-diabetes-association-ada-2026-scientific-sessions-showcasing-asc30-clinical-data-and-exciting-preclinical-findings-from-asc37-and-asc39-302793255.html | | Preclinical (combination) | ASC30_39 fixed-dose combination tablet, oral dosing in dogs | Excellent oral bioavailability, high drug exposure and half-life up to 12 hours; good compatibility, room-temperature stability and small pill size supporting a once-daily single-pill GLP-1-plus-amylin regimen | Source: https://www.prnewswire.com/news-releases/ascletis-announces-fixed-dose-combination-of-asc30-once-daily-oral-small-molecule-glp-1r-agonist-and-asc39-once-daily-oral-small-molecule-amylin-selective-amylin-receptor-agonist-for-clinical-development-302735615.html | | Company / development | Ascletis Pharma obesity pipeline | ASC39 selected as clinical development candidate in early 2026; U.S. FDA IND for ASC39 oral tablets and for the ASC30_39 fixed-dose combination planned for Q3 2026 | Source: https://www.prnewswire.com/news-releases/ascletis-announces-fixed-dose-combination-of-asc30-once-daily-oral-small-molecule-glp-1r-agonist-and-asc39-once-daily-oral-small-molecule-amylin-selective-amylin-receptor-agonist-for-clinical-development-302735615.html | ## Commonly Discussed Benefits Weight Management: https://peptrackerpro.com/benefits/weight-management Metabolism: https://peptrackerpro.com/benefits/metabolism Fat Loss: https://peptrackerpro.com/benefits/fat-loss Muscle Preservation: https://peptrackerpro.com/benefits/muscle-preservation Researching ASC39? Track it, set reminders, and keep notes in the free app. Track in App (https://app.peptrackerpro.com/?add=asc39) ## Safety & Cautions - Preclinical / IND-enabling only - no human safety or efficacy data yet, and no IND cleared as of July 2026 - Cross-species translation is uncertain: eloralintide-matching potency and weight loss in rats and cell assays may not reproduce in humans - Human tolerability of an amylin-selective oral agonist (nausea, vomiting, GI effects) is unproven - Human weight-loss magnitude, durability and lean-mass benefit are unknown - Combination (ASC30_39 FDC) benefit and safety are likewise unproven in people - Not available outside eventual clinical trials; not FDA-approved and not a compounding-eligible peptide - Any 'ASC39' offered by a vendor is unverified - it is a proprietary investigational small molecule ## Comparisons See how ASC39 compares to related peptides: ASC39 vs ALV-200: https://peptrackerpro.com/compare/asc39-vs-alv-200 ASC39 vs Amycretin: https://peptrackerpro.com/compare/asc39-vs-amycretin ASC39 vs ASC30: https://peptrackerpro.com/compare/asc39-vs-asc30 ASC39 vs Cagrilintide: https://peptrackerpro.com/compare/asc39-vs-cagrilintide ASC39 vs Eloralintide: https://peptrackerpro.com/compare/asc39-vs-eloralintide ASC39 vs Petrelintide: https://peptrackerpro.com/compare/asc39-vs-petrelintide ## Calculator Tools Use our research tools to explore dosing and reconstitution data: Reconstitution Calculator: https://peptrackerpro.com/calculators ## Citations 1. [1] Ascletis - Oral Small Molecule Amylin Receptor Agonist ASC39 Demonstrated Eloralintide-like Amylin Selectivity and Efficacy in Preclinical Models (Mar 17, 2026) PubMed (https://www.prnewswire.com/news-releases/oral-small-molecule-amylin-receptor-agonist-asc39-demonstrated-eloralintide-like-amylin-selectivity-and-efficacy-in-preclinical-models-302715843.html) 2. [2] Ascletis Announces Fixed-Dose Combination of ASC30 (oral GLP-1R agonist) and ASC39 (oral amylin-selective agonist) for Clinical Development (Apr 7, 2026) PubMed (https://www.prnewswire.com/news-releases/ascletis-announces-fixed-dose-combination-of-asc30-once-daily-oral-small-molecule-glp-1r-agonist-and-asc39-once-daily-oral-small-molecule-amylin-selective-amylin-receptor-agonist-for-clinical-development-302735615.html) 3. [3] Ascletis Reinforces Its Differentiated Obesity Portfolio at ADA 2026 - ASC30 Clinical Data and Preclinical Findings from ASC37 and ASC39 (June 2026) PubMed (https://www.prnewswire.com/news-releases/ascletis-reinforces-its-differentiated-obesity-portfolio-at-american-diabetes-association-ada-2026-scientific-sessions-showcasing-asc30-clinical-data-and-exciting-preclinical-findings-from-asc37-and-asc39-302793255.html) 4. [4] BioWorld - Ascletis Pharma selects ASC-39 as clinical development candidate PubMed (https://www.bioworld.com/articles/729670-ascletis-pharma-selects-asc-39-as-clinical-development-candidate) ### Keep researching in the app - Log ASC39 to your private tracker - Set a dosing reminder - Compare it side-by-side with your stack Open PepTracker Pro Free: https://app.peptrackerpro.com/?add=asc39 Browse more peptides: https://peptrackerpro.com/peptides ## Related Peptides ### ALV-200 Low Evidence ALV-200 is Alveus Therapeutics' highly selective amylin receptor 3 (AMYR3) peptide agonist in IND-enabling development for obesity, designed to capture amylin's weight-loss and lean-mass-preserving benefits while avoiding the nausea and aversion tied to calcitonin-receptor activation. It is engineered for once-weekly dosing. View Details: https://peptrackerpro.com/peptides/alv-200 \+ Compare: https://peptrackerpro.com/compare?select=alv-200 Track in App: https://app.peptrackerpro.com/?add=alv-200 ### Amycretin Medium Evidence A unimolecular GLP-1 and amylin receptor dual agonist in Phase 3 trials, available in both subcutaneous and oral formulations, with up to 22% weight loss in Phase 1b/2a. Weight Management (https://peptrackerpro.com/benefits/weight-management)Appetite Regulation (https://peptrackerpro.com/benefits/appetite-regulation)Metabolism (https://peptrackerpro.com/benefits/metabolism)Fat Loss (https://peptrackerpro.com/benefits/fat-loss)+1 more View Details: https://peptrackerpro.com/peptides/amycretin \+ Compare: https://peptrackerpro.com/compare?select=amycretin Track in App: https://app.peptrackerpro.com/?add=amycretin ### ASC30 Low Evidence An oral once-daily small-molecule GLP-1 receptor agonist developed by Ascletis Pharma, showing 5.4–7.7% placebo-adjusted weight loss at 13 weeks in Phase 2, with in vitro potency 2–3x greater than orforglipron. Weight Management: https://peptrackerpro.com/benefits/weight-management Appetite Regulation: https://peptrackerpro.com/benefits/appetite-regulation Metabolism: https://peptrackerpro.com/benefits/metabolism Fat Loss: https://peptrackerpro.com/benefits/fat-loss View Details: https://peptrackerpro.com/peptides/asc30 \+ Compare: https://peptrackerpro.com/compare?select=asc30 Track in App: https://app.peptrackerpro.com/?add=asc30 ### Cagrilintide High Evidence A long-acting amylin analog studied for appetite regulation; NDA filed for CagriSema (cagrilintide + semaglutide) combination in December 2025, with FDA review expected in 2026. Weight Management: https://peptrackerpro.com/benefits/weight-management Appetite Regulation: https://peptrackerpro.com/benefits/appetite-regulation Metabolism: https://peptrackerpro.com/benefits/metabolism View Details: https://peptrackerpro.com/peptides/cagrilintide \+ Compare: https://peptrackerpro.com/compare?select=cagrilintide Track in App: https://app.peptrackerpro.com/?add=cagrilintide ### Eloralintide Medium Evidence A selective, long-acting amylin receptor agonist in Phase 3 trials for obesity, offering a GLP-1-independent weight loss mechanism with up to 20.1% weight loss in Phase 2. View Details: https://peptrackerpro.com/peptides/eloralintide \+ Compare: https://peptrackerpro.com/compare?select=eloralintide Track in App: https://app.peptrackerpro.com/?add=eloralintide ### Petrelintide Medium Evidence A long-acting amylin analog in late-stage clinical development for chronic weight management, designed to deliver double-digit weight loss with a tolerability profile comparable to placebo. Weight Management: https://peptrackerpro.com/benefits/weight-management Metabolism: https://peptrackerpro.com/benefits/metabolism Fat Loss: https://peptrackerpro.com/benefits/fat-loss Appetite Regulation: https://peptrackerpro.com/benefits/appetite-regulation View Details: https://peptrackerpro.com/peptides/petrelintide \+ Compare: https://peptrackerpro.com/compare?select=petrelintide Track in App: https://app.peptrackerpro.com/?add=petrelintide ## Structured data ```json [ { "@context": "https://schema.org", "@type": "Organization", "name": "PepTracker Pro", "url": "https://peptrackerpro.com", "logo": "https://peptrackerpro.com/favicon.png", "description": "Evidence-based educational resource dedicated to improving peptide research literacy.", "contactPoint": { "@type": "ContactPoint", "email": "hello@peptrackerpro.com", "contactType": "customer support" }, "sameAs": [] }, { "@context": "https://schema.org", "@type": "MedicalWebPage", "name": "ASC39", "description": "ASC39 is Ascletis Pharma's investigational once-daily oral small-molecule amylin-selective amylin receptor agonist for obesity. 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ASC39 is Ascletis Pharma's investigational once-daily oral small-molecule amylin-selective amylin receptor agonist for obesity. In head-to-head preclinical assays it matched Eli Lilly's injectable peptide eloralintide on amylin-receptor potency, selectivity over the calcitonin receptor, and weight loss in diet-induced obese rats. Ascletis plans to file a U.S. FDA IND for ASC39 - and for a fixed-dose combination with its oral GLP-1 agonist ASC30 - in the third quarter of 2026." } }, { "@type": "Question", "name": "Those tracking amylin-selective, lean-mass-sparing mechanisms and how they compare to eloralintide, cagrilintide and petrelintide?", "acceptedAnswer": { "@type": "Answer", "text": "ASC39 is a research peptide studied in preclinical models. ASC39 is Ascletis Pharma's investigational once-daily oral small-molecule amylin-selective amylin receptor agonist for obesity. In head-to-head preclinical assays it matched Eli Lilly's injectable peptide eloralintide on amylin-receptor potency, selectivity over the calcitonin receptor, and weight loss in diet-induced obese rats. Ascletis plans to file a U.S. FDA IND for ASC39 - and for a fixed-dose combination with its oral GLP-1 agonist ASC30 - in the third quarter of 2026." } }, { "@type": "Question", "name": "Individuals interested in all-oral GLP-1-plus-amylin combinations (ASC30_39 FDC) as an oral analog of CagriSema/MariTide?", "acceptedAnswer": { "@type": "Answer", "text": "ASC39 is a research peptide studied in preclinical models. ASC39 is Ascletis Pharma's investigational once-daily oral small-molecule amylin-selective amylin receptor agonist for obesity. In head-to-head preclinical assays it matched Eli Lilly's injectable peptide eloralintide on amylin-receptor potency, selectivity over the calcitonin receptor, and weight loss in diet-induced obese rats. Ascletis plans to file a U.S. FDA IND for ASC39 - and for a fixed-dose combination with its oral GLP-1 agonist ASC30 - in the third quarter of 2026." } }, { "@type": "Question", "name": "Researchers and investors watching Ascletis's obesity portfolio and the 2026 'amylin renaissance'?", "acceptedAnswer": { "@type": "Answer", "text": "ASC39 is a research peptide studied in preclinical models. ASC39 is Ascletis Pharma's investigational once-daily oral small-molecule amylin-selective amylin receptor agonist for obesity. In head-to-head preclinical assays it matched Eli Lilly's injectable peptide eloralintide on amylin-receptor potency, selectivity over the calcitonin receptor, and weight loss in diet-induced obese rats. Ascletis plans to file a U.S. FDA IND for ASC39 - and for a fixed-dose combination with its oral GLP-1 agonist ASC30 - in the third quarter of 2026." } } ] } ] ```