Retension Pharmaceuticals filed an S-1 to go public on the Nasdaq Capital Market under the ticker “RTSN.” The Falls Church, VA-based clinical-stage biotech is developing RTN-001, a next-generation PDE-5 inhibitor designed to improve blood pressure control by enhancing nitric oxide-cGMP signaling. Proceeds are earmarked to complete a Phase 2b study and prepare for Phase 3, with Leerink Partners, Guggenheim Securities, Oppenheimer & Co., and Titan Partners as underwriters.

Business Description

Retension Pharmaceuticals is a clinical-stage biopharmaceutical company developing RTN-001, a once-daily, oral, next-generation PDE-5 inhibitor aimed at improving blood pressure control in uncontrolled and resistant hypertension. Unlike first-generation PDE-5 inhibitors, RTN-001 was designed via a proprietary surface chemistry-driven platform to enhance bioavailability and distribution to cardiovascular smooth muscle tissues in the central vasculature, with the goal of potentiating endogenous nitric oxide-cGMP signaling for more consistent and sustained blood pressure reduction.

The company is running a randomized, double-blind, placebo-controlled Phase 2b study in uncontrolled hypertension to identify optimal dosing of a modified-release formulation intended to support 24-hour control and improved tolerability. Earlier Phase 2 pilot trials showed clinically meaningful, placebo-adjusted reductions in both peripheral and central blood pressure and a tolerability profile consistent with the PDE-5 inhibitor class. Retension plans to use Phase 2b results to inform a Phase 3 trial and is also exploring additional cardiovascular or renal indications where nitric oxide-cGMP pathway modulation may be beneficial.

Market Overview

• Total addressable market: Hypertension affects ~1.4 billion adults globally and ~120 million adults in the U.S.
• Market growth: Heightened clinical focus from tighter AHA targets (130/80 mmHg) and FDA guidance recognizing BP reduction as a surrogate endpoint.
• Market position: Clinical-stage developer of a next-generation PDE-5 inhibitor (RTN-001) engineered for central vascular smooth muscle distribution.
• Key competitors: Established antihypertensive classes (ACE inhibitors, ARBs, calcium channel blockers, diuretics, beta blockers) and other emerging cardiometabolic approaches.
• Industry trends: Emphasis on 24-hour blood pressure control, central blood pressure relevance, streamlined FDA pathways, and combination therapy strategies.

Operational Metrics

• Customers: Pre-revenue; no commercial customers
• Locations: Headquarters in Falls Church, Virginia
• Geographic presence: Ongoing U.S. Phase 2b trial; prior Phase 2 pilot trials conducted in the UK and Germany
• Partnerships: Exclusive sublicense for RTN-001 via Redux/Kadmon; relies on third-party CROs and CMOs
• Orders/GMV: Not applicable (pre-commercial)
• Other key metrics: Phase 2b initiated in October 2025 across ~31 U.S. sites; ~40% enrolled as of September 11, 2026; 243 participants exposed to RTN-001 across nine completed trials; 12 employees as of September 16, 2026

Financials Highlights

• Revenue (current): None
• Operating income: $(7.8) million loss (six months ended June 30, 2026)
• Net income: $(7.5) million loss (six months ended June 30, 2026); $(6.3) million loss (FY2025)

Management

• Eric Keller, Chief Executive Officer - Biopharma executive and company co-founder; led prior deals at Surface Logix/Nano Terra and holds a J.D. from Boston College.
• Paul Sweetnam, Ph.D., Chief Scientific Officer - Former CSO at Surface Logix; led the early development of RTN-001; prior roles at Bayer, Pfizer, and Nova.
• Alison D. Schecter, M.D., Chief Medical Officer - Cardiovascular drug development leader; prior roles at Mineralys, Selecta, Sanofi-Genzyme; physician-scientist with extensive clinical leadership.
• Alex Schwartz, Chief Financial Officer - Capital markets and biotech FP&A/IR experience at Ventyx, Allakos, NGM Biopharmaceuticals, and Esperion; former biotech equity analyst.
• Sabine Bisson, Ph.D., Chief Operating Officer - Nearly 20 years in biopharma development; led programs at Regeneron, Cellectis, and Volastra; experience across oncology and cardiometabolic assets.
• Michael Joseph Berendt, Ph.D., Executive Chairman - Industry veteran and former senior R&D leader at Bayer and Pfizer; multiple biotech CEO/board roles.

IPO Structure

• Issuer: Retension Pharmaceuticals, Inc.
• Filing date: September 18, 2026
• Proposed ticker: RTSN
• Exchange: Nasdaq Capital Market
• Lead underwriters: Leerink Partners, Guggenheim Securities, Oppenheimer & Co., Titan Partners
• Use of proceeds: Complete the Phase 2b clinical trial and prepare, support, and advance the planned Phase 3 trial of RTN-001; remainder for general corporate purposes.

Original SEC Filing: Retension Pharmaceuticals, Inc. - S-1 - Sep. 18, 2026