Rein Therapeutics Inc.

What they do

Rein Therapeutics develops novel therapies for orphan pulmonary and fibrosis indications with no approved or limited effective treatments. Its lead candidate is LTI-03, an inhaled dry powder peptide in a Phase 2 trial in idiopathic pulmonary fibrosis (IPF). It also holds LTI-01, a proenzyme that completed a Phase 2a trial in loculated pleural effusion, and preclinical programs in cystic fibrosis and a Cav1-targeted peptide for systemic fibrosis. Development of LTI-01 was paused indefinitely in the fourth quarter of 2025.

Revenue drivers

• LTI-03 (IPF) — Lead clinical program; no revenue to date, and the company has never generated revenue from product sales.
• LTI-01 (loculated pleural effusion) — Completed Phase 2a and Phase 1b trials, but development activities were paused indefinitely in Q4 2025; no revenue.
• Preclinical programs — Cystic fibrosis and Cav1 peptide programs for systemic fibrosis; no revenue and no disclosed timelines.

Recent performance

Reported annual revenue was $0.00 in each year from 2021 through 2025, and quarterly revenue was $0.00 for the quarters ended September 30, 2025 through June 30, 2026. Net losses were $62.9 million in 2024 and $49.9 million in 2025, with diluted EPS of -$3.51 and -$1.96, respectively. For the three months ended June 30, 2026, net loss was $6.4 million versus $6.8 million in the prior-year quarter. Operating cash flow was -$22.3 million in 2024 and -$19.4 million in 2025. As of June 30, 2026, total assets were $66.0 million, total liabilities $10.8 million, equity $55.2 million, and cash and equivalents $8.5 million.

Strategy

The company's stated priority is advancing LTI-03 through the RENEW Phase 2 trial in IPF, which began screening patients in May 2025 and dosed its first patient in March 2026. RENEW is designed to enroll approximately 120 patients across up to 50 sites in the United States, United Kingdom, Germany, Australia and Poland, with a primary endpoint of treatment-emergent adverse events through Week 24 and secondary measures of forced vital capacity and high-resolution CT. In October 2025 the EMA authorized German and Polish sites, and in January 2026 LTI-03 received EMA orphan drug designation. LTI-01 development was paused indefinitely in Q4 2025. The company funded operations in part through a May 2026 underwritten public offering of 57,500,000 shares at $1.00 per share, raising approximately $57.5 million gross and $53.1 million net.

Risks

• No revenue and recurring losses — The company has never generated revenue from product sales and had an accumulated deficit of $413.5 million as of June 30, 2026.
• Early-stage clinical failure risk — LTI-03 is the sole active clinical candidate, and its Phase 2 RENEW trial's primary endpoint is safety, not efficacy.
• Financing and dilution risk — Cash and equivalents were $8.5 million at June 30, 2026, and the company funded itself through offerings including 57,500,000 shares sold at $1.00 in May 2026.
• Listing and regulatory risk — An 8-K filed August 27, 2026 disclosed a delisting notice or listing-rule failure, and the company also reported an indefinite pause of LTI-01 development in Q4 2025.

Outlook

Management expects to report initial interim data on some proportion of patients in the RENEW Phase 2 trial of LTI-03 in the fourth quarter of 2026. Enrollment is ongoing across all countries in the trial, with sites activated as of the latest quarterly report. The company states it has not completed development of any product candidate and has never generated an operating profit.