Rein Therapeutics, Inc.

and Recent Developments We are a clinical stage biopharmaceutical company focused on developing novel therapies for the treatment of orphan pulmonary and fibrosis indications with no approved or limited effective treatments. We currently have two product candidates in clinical development, LTI-03 and LTI-01, however, due to insufficient funding we have paused development of LTI 01 for an undetermined period of time and are prioritizing LTI 03. Our pipeline includes: LTI-03, a peptide, for which we conducted a Phase 1b dose-ranging, placebo-controlled safety, tolerability, and pharmacodynamic biomarker activity trial in development for the treatment of Idiopathic Pulmonary Fibrosis, or IPF, that has demonstrated the ability to protect healthy lung epithelial cells and reduce pro-fibrotic signaling; LTI-01, a proenzyme that completed a Phase 2a dose-ranging, placebo-controlled trial and a Phase 1b safety, tolerability and proof of mechanism trial in loculated pleural effusion, or LPE, patients, an indication that has no approved drug treatment; and preclinical programs targeting cystic fibrosis and a peptide program focused on the Cav1 protein for systemic fibrosis indications. In June 2024, we decided to temporarily delay clinical development of LTI-01 in an effort to focus our resources on clinical development of LTI-03 and until additional funds are raised. In the fourth quarter of 2024, we determined that the temporary delay of further clinical development of LTI-01 may not be a short-term measure.