Regeneron sits at the seam between biologics and the peptide story in a few specific ways. The COURAGE Phase 2 data — semaglutide alone produced 6.5% lean mass loss at 26 weeks; pairing it with trevogrumab 200 mg cut that in half; adding garetosmab pushed combined fat-mass loss to 92.6% — keep driving the obesity-pipeline conversation around GLP-1 lean-mass preservation.
April 23 brought Otarmeni (lunsotogene parvec-cwha), Regeneron's gene therapy for certain inherited hearing loss and the first gene therapy cleared under the FDA national priority voucher program. It is not a peptide, but it cements Regeneron's strategy of partnering with the FDA's expedited-access regime.
May 19's Parabilis Medicines S-1 named a research deal worth up to $2B with Regeneron, signed shortly before Parabilis filed to IPO under PBLS. The collaboration targets undruggable protein-protein interactions through Parabilis's helical peptide (Helicon) platform, with zolucatetide (FOG-001) the lead. See [[parabilis-medicines]], [[trevogrumab]], and [[courage-trial]].
Regeneron Pharmaceuticals and Parabilis Medicines announced May 18 a strategic research collaboration to discover and develop antibody-Helicon conjugates (AHCs) — a novel modality combining Regeneron's antibody platform with Parabilis's Helicon stabilized helical peptide technology. Deal structure: $50M upfront, $75M equity commitment, and up to $2.2B in development and regulatory milestones across an initial five targets, plus tiered royalties. The Helicon platform locks peptides into their bioactive helical conformation, enabling targeting of historically undruggable protein-protein interaction surfaces that small molecules cannot access. The conjugate format pairs antibody-mediated tissue homing with peptide payload delivery — an extension of the broader peptide-drug-conjugate field that included Bicycle Therapeutics' bicyclic peptide-MMAE conjugates and Avacta's FAP-activated PDCs. The deal is the largest single peptide-platform partnership announced in 2026.
Parabilis Medicines (formerly FogPharma) filed its S-1 on May 19 to list on Nasdaq under ticker PBLS, seeking ~$100M to fund Phase 3 of zolucatetide (FOG-001), a stabilized helical peptide and the first direct inhibitor of the β-catenin:TCF interaction. As of February 16, 38 desmoid-tumor patients were dosed; 25 had sufficient follow-up to be response-evaluable, all showed tumor reduction, and 74% of the 19 patients with ≥2 post-baseline scans hit RECIST 1.1 objective response. The IPO follows a $305M Series F in January and a Regeneron research deal worth up to $2B. FDA granted fast track designation for desmoid tumors.
Regeneron's COURAGE Phase 2 data presented at EASD 2025 continue to drive obesity-pipeline conversations. Semaglutide alone produced 6.5% lean mass loss at 26 weeks; sema + trevogrumab 200 mg cut that to 3.3% (~half), and the triplet with garetosmab (anti-activin A) pushed to 2.0% lean mass loss with 92.6% fat-mass loss. The triplet had higher discontinuation for tolerability. Full COURAGE completion is expected late 2026, with Phase 3 initiation likely 2027.
The FDA granted accelerated approval April 23 for Regeneron's Otarmeni (lunsotogene parvec-cwha), a gene therapy for certain forms of genetic hearing loss. Otarmeni is the first gene therapy cleared under the FDA's National Priority Voucher program and will be offered to eligible patients at no cost. The approval validates the priority voucher pathway's applicability beyond GLP-1 drugs and establishes regulatory precedent that peptide developers may invoke if the July PCAC meeting produces favorable reclassification recommendations.