Peptide News Digest

Pharming Joenja Pediatric APDS Approval, Penn Nature Health GLP-1 Reddit Study, Pediatrics 310x GLP-1 in Kids

Pharming Joenja wins pediatric APDS approval, Penn Nature Health flags GLP-1 side effects from 400K Reddit posts, Pediatrics finds 310x pediatric GLP-1 rise.

6 stories · Covering regulatory, research, clinical-trials, industry

Editor's Note

Saturday news coverage bridged Friday's Pharming Joenja pediatric APDS FDA approval and a pair of Penn/AAP publications that reshaped the pediatric obesity treatment conversation in the same week Novo Nordisk announced the STEP Young Phase 3 win in children aged 6 to under 12. A University of Pennsylvania Engineering team published in Nature Health an AI analysis of 400,000+ Reddit posts from 70,000+ GLP-1 users that surfaced reproductive and thermoregulation side effects underreported in clinical trials — the finding does not establish causation but flags safety signals worth investigating in a class now prescribed to millions of adults and increasingly to children. Separately, the AAP Pediatrics journal published a Sept 4 study documenting a 310-fold increase in GLP-1 prescribing in children aged 8-11 without diabetes and with obesity between 2019 and mid-2026, from 0.03% to 9.3% — the population most enriched with severe obesity (93.7%) and cardiometabolic comorbidities (65.2%). Mabwell's anti-ST2 monoclonal antibody 9MW1911 posted an 81% reduction in moderate-to-severe COPD exacerbations at the high dose in a Phase 1b/2a trial presented at ERS Congress. Roivant analyst chorus continued through the weekend, with Leerink flagging up to $10 billion peak sales potential for mosliciguat across multiple pulmonary hypertension indications. Corbus CANYON-1 Phase 1b topline for the peripherally-restricted CB1 inverse agonist CRB-913 drops Monday morning.

FDA Approves Pharming's Joenja (Leniolisib) as First Treatment for Children Aged 4-11 With Activated Phosphoinositide 3-Kinase Delta Syndrome (APDS); U.S. Launch October 2026

Pharming Group N.V. (NASDAQ: PHAR) announced Friday September 11, 2026 that the FDA approved the company's supplemental new drug application (sNDA) for Joenja (leniolisib, an oral selective phosphoinositide 3-kinase delta (PI3Kδ) inhibitor) at 40 mg and 50 mg twice-daily dosing for children aged 4 to 11 years weighing at least 27 kg with activated phosphoinositide 3-kinase delta syndrome (APDS). Joenja becomes the first FDA-approved treatment for children aged 4-11 with APDS, a rare primary immunodeficiency driven by gain-of-function mutations in the PIK3CD or PIK3R1 genes producing constitutive PI3Kδ pathway activation and recurrent sinopulmonary infections. Approval follows the February 2026 complete response letter, which required additional supportive data. The newly approved doses will be available through Pharming's specialty distribution network and patient-support infrastructure starting October 2026. Joenja was originally approved in March 2023 for APDS patients aged 12 and older; the pediatric label expansion extends the treated population substantially.

University of Pennsylvania Engineering Publishes Nature Health AI Analysis of 400,000+ Reddit Posts from GLP-1 Users; Flags Menstrual, Temperature, and Fatigue Side Effects Underreported in Clinical Trials

A University of Pennsylvania School of Engineering and Applied Science team led by Neil K.R. Sehgal, Sharath Chandra Guntuku, Lyle Ungar, and Jena Shaw Tronieri published in Nature Health (Vol. 1, Issue 8, page 806; DOI 10.1038/s44360-026-00108-y) an AI-driven analysis of 410,198 Reddit posts from 67,008 users self-reporting use of semaglutide (Ozempic, Wegovy, Rybelsus) or tirzepatide (Mounjaro, Zepbound) between May 2019 and June 2025. Gastrointestinal side effects dominated as expected (nausea 36.9%, fatigue 16.7%, vomiting 16.3%, constipation 15.3%, diarrhea 12.6%), and 43.5% of users reported at least one side effect. Two categories emerged as underreported in trials and worth investigation: reproductive symptoms including menstrual cycle changes and heavy bleeding (~4%), and thermoregulation symptoms (chills, hot flashes). The authors caution that Reddit users skew younger, male, and U.S.-based and note the analysis cannot establish causation. The hypothalamus regulates hunger, hormones, reproduction, and body temperature — a plausible biological substrate. Coverage syndicated Saturday September 12, 2026 (ScienceDaily and other outlets) after the Sept 13 journal publication date.

AAP Pediatrics Journal Study: GLP-1 Prescribing in U.S. Children Aged 8-11 With Obesity Rose 310-fold From 2019 to Mid-2026 (0.03% to 9.3%); 93.7% Have Severe Obesity, 65.2% Have Comorbidities

A study published September 4, 2026 in the American Academy of Pediatrics journal Pediatrics (DOI: 10.1542/peds.2026-077048) documented a 310-fold increase in GLP-1 receptor agonist prescribing in U.S. children aged 8 to 11 without diabetes and with obesity between 2019 and mid-2026 — from 0.03% of eligible children in 2019 to 9.3% in 2026. Prescribing captured liraglutide, semaglutide, and tirzepatide across the age group. Recipient characteristics: 93.7% had class II or III severe obesity at baseline, 65.2% had at least one weight-related comorbidity, and approximately 25% had prediabetes. Socioeconomic gradients were substantial: children in upper-income communities were prescribed GLP-1s at 55% higher rates than those in lower-income communities. The trend accelerated notably following the December 2022 FDA approval of Wegovy for adolescents 12 and older (implicit off-label use in the younger cohort) and shifted further after the AAP's January 2023 pediatric obesity clinical practice guideline. FoodNavigator syndicated the study September 10, 2026 alongside broad coverage this week; the data show how quickly clinical practice moved ahead of the STEP Young Phase 3 topline announced September 7.

Mabwell 9MW1911 Anti-ST2 Monoclonal Antibody Reduces COPD Moderate-to-Severe Exacerbations by 81% at 900 mg in Phase 1b/2a Trial; Phase 3 Expected End of 2026 (ERS Congress Coverage)

Mabwell Biosciences presented at the European Respiratory Society Congress 2026 in Barcelona (September 5-9, 2026) — with syndicated press coverage continuing through Saturday September 12 — Phase 1b/2a results for 9MW1911, an anti-ST2 monoclonal antibody developed on Mabwell's B-lymphocyte screening platform in China. In the 9MW1911-C03 study of former smokers with moderate-to-severe COPD, the annualized rate of moderate-to-severe exacerbations was reduced by 81% at the 900 mg dose and 24% at the 600 mg dose versus placebo; annualized severe exacerbation rate reductions were 100% and 47% respectively. The Phase 3 trial is expected to initiate around end of 2026 in China; the FDA has cleared the IND application for a Phase 2a U.S. trial. 9MW1911 targets ST2 (the IL-33 receptor) — the same biological pathway targeted by Regeneron/Sanofi's itepekimab and GSK's depemokimab in COPD. Sanofi and Regeneron's Phase 3 AERIFY-1 and AERIFY-2 itepekimab trials in COPD had mixed results reported May 2025; Mabwell's data support continued ST2 blockade testing in the disease.

Roivant PHocus Analyst Chorus Continues Into the Weekend: Leerink Flags Up to $10 Billion Peak Sales Potential for Mosliciguat Across Multiple Pulmonary Hypertension Indications

Roivant Sciences (NASDAQ: ROIV) analyst commentary continued through the weekend following Tuesday's Pulmovant Phase 2 PHocus mosliciguat win, with Leerink Partners' David Risinger flagging up to $10 billion peak sales potential for mosliciguat across multiple pulmonary hypertension indications. The Leerink estimate substantially exceeds the ~$3 billion PH-ILD-only estimate Guggenheim disclosed Wednesday September 9. Other analyst peak sales projections ranged from $1.5 billion to $5 billion depending on indication assumptions and market-share methodology. The week's analyst upgrade sequence: Jefferies to $52 (from $42), Guggenheim to $46 (from $42), Piper Sandler to $55 (from $40), TD Cowen to $55 (from $50), BofA also raised. Consensus 12-month price target clusters around $50-55. The PHocus trial produced a 56.3% placebo-adjusted PVR reduction at Week 16 (p<0.0001), 6MWD +35.2 meters, and NT-proBNP −357.7 pg/mL (−53.2%). The Phase 3 PHrontier trial in approximately 375 patients is enrolling. Mosliciguat's mechanism (inhaled soluble guanylate cyclase activator working independently of heme and nitric oxide) differentiates it from sGC stimulators like Bayer's Adempas (riociguat) and prostacyclin analogs like United Therapeutics' Tyvaso (treprostinil).

Corbus CANYON-1 Phase 1b Topline Data for CRB-913 Obesity Trial Set for Monday September 14 Morning Conference Call; Weekend Positioning Watch for Non-Incretin Obesity Landscape

Corbus Pharmaceuticals (NASDAQ: CRBP) enters the weekend before Monday September 14, 2026 at 8:00 a.m. EDT conference call disclosing Phase 1b CANYON-1 topline data for CRB-913 (once-daily oral peripherally-restricted CB1 inverse agonist for obesity). The 16-week double-blind placebo-controlled dose-ranging study enrolled 240 obese non-diabetic U.S. adults across once-daily doses of 20 mg, 40 mg, and 60 mg (titrated from 20 mg) with a 4-week safety follow-up (NCT07310901). Harold Bays MD (investigator) will join Corbus management on the call. Investor focus is on the CB1 inverse agonist class safety-versus-efficacy trade-off — the peripheral restriction (approximately 15-fold lower brain penetration than monlunabant in preclinical models) is designed to preserve dose-responsive weight loss while limiting the psychiatric side effects that led to the 2008 withdrawal of Sanofi's Acomplia (rimonabant). Clean tolerability plus dose-responsive weight loss would enable Phase 2 initiation and position CRB-913 as a differentiated non-incretin add-on or alternative to the GLP-1 class. Monday's readout is one of the most-watched non-GLP-1 obesity data points on the September calendar.