Research & literature

The American Diabetes Association's 86th Scientific Sessions run June 5-8, 2026 in New Orleans, with GLP-1-based therapies featured in seven of eight major clinical-trial result sessions. Phase 3 REIMAGINE 1, 2 and 3 data for CagriSema (cagrilintide + semaglutide, Novo Nordisk) are scheduled to be presented for the first time on Sunday, June 7. Phase 2b data for the oral small-molecule GLP-1 agonist elecoglipron (AZD5004/ECC5004) in obesity (VISTA) and type 2 diabetes (SOLSTICE) are scheduled for June 7-8. Event/agenda noted here as scheduled; per site policy no efficacy figures are recorded until primary readouts are published. Flagged for capture in the next refresh.

Phase 3 TRANSCEND-T2D-1 (manufacturer-reported topline; Eli Lilly press release dated May 28, 2026 ahead of the ADA 86th Scientific Sessions; full results scheduled for presentation at the ADA retatrutide symposium on June 6, 2026): in adults with type 2 diabetes, retatrutide — an investigational once-weekly GIP/GLP-1/glucagon triple receptor agonist peptide — was reported to lower A1C by up to an average of 2.0% and body weight by up to an average of 36.6 lb (16.8%) at 40 weeks [human]. This is the peptide's first dedicated Phase 3 type 2 diabetes readout, complementing the obesity result in TRIUMPH-1 (ResearchArticles id 9). The figures are manufacturer-reported topline values and have not yet been peer-reviewed; retatrutide is not FDA-approved and is legally available only to participants in Lilly clinical trials. Primary source on file: PeptideSources id 37 (investor.lilly.com TRANSCEND-T2D-1 release).

Peer-reviewed pharmacovigilance study (Nature Health, 2026; DOI 10.1038/s44360-026-00108-y) applying large-scale natural-language analysis to 410,198 Reddit posts (May 2019-June 2025) mentioning semaglutide or tirzepatide. Of 67,008 users who self-reported use, 43.5% described at least one side effect. Gastrointestinal symptoms predominated: nausea (36.9%), fatigue (16.7%), vomiting (16.3%), constipation (15.3%) and diarrhoea (12.6%). The study surfaced under-recognised signals not well captured in current labelling or trials, notably reproductive symptoms (e.g., menstrual irregularities) and temperature-related complaints (e.g., chills, hot flushes). Authors conclude that large-scale social-media analysis can complement traditional pharmacovigilance for detecting emerging real-world safety signals of GLP-1 receptor agonists. Reported as observational real-world safety data; no dosing guidance recorded.

On May 22, 2026 the FDA granted accelerated approval to Hepcludex (bulevirtide-gmod), the first and only approved US treatment for chronic hepatitis delta virus (HDV) infection in adults without cirrhosis or with compensated cirrhosis. Bulevirtide is an HBV/HDV entry inhibitor (NTCP receptor blocker), a 47-amino-acid lipopeptide given subcutaneously. Approval was based on HDV RNA reduction and ALT normalization in the Phase 3 MYR301 study; clinical-outcome benefit not yet established (confirmatory trial required).

Phase 3 TRIUMPH-1 (Eli Lilly press release May 21, 2026): Retatrutide 12 mg produced 28.3% body weight loss (70.3 lb) over 80 weeks in adults with obesity without T2D. 9 mg: 25.9% (64.4 lb). 4 mg: 19.0% (47.2 lb). All doses met primary and key secondary endpoints. 45.3% of 12 mg patients achieved ≥30% weight loss (bariatric-surgery threshold). 104-week extension (BMI ≥35): 30.3% (85.0 lb). Additional readouts: TRIUMPH-4 (knee OA, 28.7%), TRANSCEND-T2D-1 (2.0% HbA1c drop). LDL-C reduction ~20% is a unique mechanistic signal. FDA NDA submission anticipated Q3–Q4 2026. Drug is not yet approved.

Partnership for Safe Medicines May 2026 roundup documenting safety risks across the GLP-1 weight-loss market: counterfeit Ozempic/Mounjaro seizures (US, Canada, Australia, India, UK), illicit online sales of unregistered semaglutide, tirzepatide and "research-use-only" retatrutide from non-FDA-registered foreign suppliers, and mass-compounding by 503A pharmacies operating at manufacturer scale. Cites concrete patient-harm cases: a Kentucky patient requiring a liver transplant after four weeks of compounded tirzepatide/B12, a Texas death linked to compounded semaglutide/B12 (Empower Pharmacy litigation), and multiple hospitalizations. Also summarizes FDA actions: 88 warning letters since Sept 2025 over false/misleading compounded GLP-1 marketing, the proposal to exclude semaglutide/tirzepatide/liraglutide from the 503B bulks list (comment period ends June 30, 2026), and several 503B outsourcers (ProRx, BPI Labs, Medisource, Olympia) exiting GLP-1 compounding.

FDA issued a warning to a 503B compounding pharmacy for producing tirzepatide after the official shortage ended, consistent with the agency's April 30, 2026 proposal to exclude GLP-1 drugs from the 503B bulks list.

FDA proposed (Apr 30, 2026; Federal Register May 1, 2026) to leave semaglutide, tirzepatide, and liraglutide OFF the 503B Bulk Drug Substances List, finding no clinical need for outsourcing-facility bulk compounding now that shortages have ended. Comment period closes June 29, 2026. Affects bulk compounding only; the drugs remain FDA-approved.

Peer-reviewed preclinical study (Nature, published 29 April 2026; DOI 10.1038/s41586-026-10427-5; Helmholtz Munich with Indiana Biosciences Research Institute and the Novo Nordisk Research Center Indianapolis). Reports a unimolecular quintuple agonist, GLP-1–GIP–lanifibranor, a peptide-drug conjugate that covalently tethers the small-molecule PPARα/γ/δ triple agonist lanifibranor to a GLP-1R/GIPR dual-incretin peptide backbone, delivering PPAR action selectively into GLP-1R- and GIPR-expressing cells. In vitro it is indistinguishable from GLP-1–GIP in incretin-receptor signalling and insulin secretion from isolated mouse islets. In vivo in obese, insulin-resistant mice it outperformed GLP-1R–GIPR co-agonism and semaglutide, further reducing body weight, food intake and hyperglycaemia via synergistic incretin and PPAR activity; the effect was blunted by genetic or pharmacological inhibition of GLP-1R, GIPR or PPARδ and absent in double incretin-receptor-knockout mice. Authors conclude the molecule has substantial therapeutic potential for obesity-linked metabolic dysfunction. Preclinical (mouse) data only; no human or dosing guidance recorded. A Publisher Correction was issued 18 May 2026 (DOI 10.1038/s41586-026-10619-z).

On April 15, 2026, FDA announced removal of 12 peptide bulk drug substances from Category 2 effective April 22, 2026, following withdrawal of nominations. No longer "significant safety risk" designation but not yet on 503A Bulks List. PCAC reviews July 23-24, 2026.

FDA primary source (Pharmacy Compounding Advisory Committee meeting notice; page content current as of 2026-04-15). The PCAC will meet July 23–24, 2026 at FDA White Oak Campus to discuss bulk drug substances nominated for inclusion on the Section 503A Bulks List. The confirmed agenda covers SEVEN peptides — not all twelve that were removed from Category 2 on April 22, 2026. Day 1 (July 23): BPC-157 (free base / acetate) — use evaluated: ulcerative colitis; KPV (free base / acetate) — wound healing and inflammatory conditions; TB-500 (free base / acetate) — wound healing; MOTS-C (free base / acetate) — obesity and osteoporosis. Day 2 (July 24): Emideltide / delta sleep-inducing peptide (DSIP) (free base / acetate) — opioid withdrawal, chronic insomnia, and narcolepsy; Semax (free base / acetate) — cerebral ischemia, migraine, and trigeminal neuralgia; Epitalon (free base / acetate) — insomnia. The listed conditions are the nominated uses FDA reviewed for each substance; they are not FDA endorsements of efficacy. PCAC recommendations are non-binding and inclusion on the 503A Bulks List has not been decided. The other five peptides removed from Category 2 in April 2026 (PEG-MGF, Melanotan II, LL-37, DiHexa, and injectable GHK-Cu) are NOT on this July agenda; their compounding status remains unresolved (they are not on the 503A Bulks List). Public docket: FDA-2025-N-6895. Comments received on or before July 9, 2026 will be provided to the Committee; the docket closes July 22, 2026. Requests to make oral presentations are due June 30, 2026. Factual regulatory reporting only; no efficacy or compounding-permission is asserted.

Health Canada public advisory (RA-81874, published 2026-04-09) warning consumers about serious health risks of unauthorized injectable peptide drugs sold online and marketed for anti-aging, weight loss, bodybuilding, athletic performance, injury recovery, sleep, mental focus, or general wellness. Health Canada has seized multiple such products and lists examples: BPC-157, CJC-1295, DSIP, Epitalon, GHK-Cu, HCG, Ipamorelin, KPV, Melanotan I and II, MOTS-C, NAD+, SS-31, TB-500, and Retatrutide, noting many other unauthorized peptide drugs exist. In Canada peptides are generally regulated as prescription drugs. Unauthorized products are illegal, have not been assessed for safety, efficacy or quality, and may contain too much, too little, none of, or unlisted/dangerous ingredients, as well as contaminants (solvents, heavy metals, particulates, microbials). Stated risks include hormonal imbalance, mood swings, blood sugar imbalance, liver or kidney damage, blood clots, growth of cancerous tumours, infections and allergic reactions. The agency stresses that "For Research Use Only - Not for Human Consumption" labelling does not make these products legal, and is working with the Canada Border Services Agency to stop unauthorized shipments. Recorded as a regulatory safety advisory; no dosing or usage guidance stored.

FDA approved Foundayo (orforglipron) April 1, 2026. First oral GLP-1 receptor agonist for weight management in adults with obesity or overweight. Eli Lilly.

FDA approved Icotyde (icotrokinra) March 17, 2026. First-in-class oral macrocyclic peptide IL-23R antagonist for moderate-to-severe plaque psoriasis. J&J / Protagonist Therapeutics.

FDA approved Yuviwel (navepegritide) Feb 27, 2026 for pediatric achondroplasia. PEGylated CNP analog activating NPR-B to promote bone growth. BioMarin.