Rein Therapeutics LTI-03 UK MHRA Phase II Clearance for RENEW Trial in Idiopathic Pulmonary Fibrosis; Caveolin-1 Peptide Mimetic Class
Rein Therapeutics (NASDAQ: RNTX) received UK Medicines and Healthcare products Regulatory Agency (MHRA) clearance in August 2026 to initiate the Phase 2 RENEW study of LTI-03 (a Caveolin-1 scaffolding domain peptide mimetic developed for the treatment of idiopathic pulmonary fibrosis, or IPF). The RENEW study is planned to enroll 120 patients with IPF and evaluate LTI-03 as an add-on to standard-of-care antifibrotic therapy (pirfenidone or nintedanib). The Caveolin-1 mimetic peptide mechanism engages the fibrotic signaling that emerges downstream of alveolar epithelial cell injury and has been characterized in preclinical fibrosis models. Rein Therapeutics is the successor entity to the 2024 reverse merger between Aileron Therapeutics and Lung Therapeutics, and LTI-03 is the lead clinical asset. The Phase 2 initiation extends the small-but-substantive peptide-therapeutic pipeline in fibrotic disease (Sitryx SIT-402, MediciNova ibudilast) beyond the incretin obesity focus that dominates recent peptide-industry headlines.