GRI Bio Amends S-1, Updates Warrants and Engagement Letter

TL;DR

**GRI Bio's continuous warrant issuances and amended engagement letter scream ongoing dilution and a desperate need for cash, making it a risky bet for new money.**

AI Summary

GRI Bio, Inc. filed an S-1/A on December 9, 2025, primarily as an exhibits-only amendment to its Registration Statement (File No. 333-291999). This filing did not disclose new revenue or net income figures, but instead updated its list of exhibits, including new warrant forms and an amended engagement letter. Key changes include the filing of Form of Placement Agent Warrant, Form of Pre-Funded Warrant, and Form of Series F Warrant, all dated December 9, 2025, under the current S-1. Additionally, an Engagement Letter with H.C. Wainwright Co., LLC, dated October 21, 2024, was amended on December 5, 2025, and filed as Exhibit 10.29. The company continues to operate as a non-accelerated filer, a smaller reporting company, and an emerging growth company. The strategic outlook remains focused on securing capital through various warrant and offering agreements, indicating ongoing financing activities to support its operations.

Why It Matters

This S-1/A filing signals GRI Bio's ongoing efforts to secure capital through various warrant and offering agreements, which is critical for a biotech company with no disclosed revenue in this filing. Investors should note the continuous issuance of new warrant forms (Series F, Pre-Funded, Placement Agent Warrants) as these can lead to dilution, impacting existing shareholder value. The amended engagement letter with H.C. Wainwright Co., LLC suggests continued reliance on investment banking services for fundraising. Competitively, frequent capital raises indicate a company in a high-burn, development-stage phase, common in the biotech sector, but also highlight potential financial pressures.

Risk Assessment

Risk Level: high — The filing is an exhibits-only amendment, meaning no new financial statements were provided, but it highlights a pattern of continuous warrant issuances (e.g., Series B-1, B-2, C-1, C-2, D-1, D-2, E, and now F Warrants) and placement agent warrants from 2024 and 2025. This suggests a high reliance on dilutive financing activities to fund operations, which is a significant risk for investors. The company's status as a 'smaller reporting company' and 'emerging growth company' further indicates its early stage and inherent financial instability.

Analyst Insight

Investors should exercise extreme caution due to the consistent pattern of dilutive financing instruments. Before considering an investment, thoroughly investigate the company's burn rate, cash position, and the specific terms of these numerous warrants to understand the full extent of potential future dilution and its impact on share price.

Key Numbers

• 333-291999 — Registration Statement File Number (Identifies the specific S-1 filing being amended.)
• 2025-12-09 — Filing Date (Date the S-1/A was filed with the SEC.)
• 2025-12-05 — Engagement Letter Amendment Date (Date the engagement letter with H.C. Wainwright Co., LLC was amended.)
• 2024-10-21 — Original Engagement Letter Date (Date of the initial engagement letter with H.C. Wainwright Co., LLC.)

Key Players & Entities

• GRI Bio, Inc. (company) — Registrant
• W. Marc Hertz, Ph.D. (person) — President and Chief Executive Officer
• H.C. Wainwright Co., LLC (company) — Placement Agent
• Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. (company) — Legal Counsel
• Haynes and Boone, LLP (company) — Legal Counsel
• Securities and Exchange Commission (regulator) — Regulatory Body
• Leanne Kelly (person) — Chief Financial Officer
• David Szekeres (person) — Director and Chairperson of the Board
• David Baker (person) — Director
• Roelof Rongen (person) — Director

FAQ

Industry Context

GRI Bio operates within the biotechnology sector, a highly competitive and capital-intensive industry. Companies in this space focus on developing novel therapeutics, often requiring significant R&D investment and facing lengthy regulatory approval processes. The industry is characterized by frequent M&A activity, strategic partnerships, and a reliance on equity financing to fund clinical trials and operations.

Regulatory Implications

As a biotechnology company, GRI Bio is subject to stringent regulatory oversight from bodies like the FDA. Changes in warrant forms and engagement letters, while not directly regulatory, are part of the financial infrastructure supporting operations that are ultimately governed by these regulations. Compliance with securities laws for filings and disclosures is paramount.

What Investors Should Do

1. Monitor future filings for details on warrant exercises and capital raises.
2. Assess the company's cash burn rate and runway.
3. Evaluate the strategic implications of the amended engagement with H.C. Wainwright.

Key Dates

• 2025-12-09: Filing of S-1/A (Exhibits Only Amendment) — Indicates ongoing efforts to update registration statements and potentially prepare for future capital raises or offerings, though no new financial data was disclosed.
• 2025-12-05: Amendment to Engagement Letter with H.C. Wainwright Co., LLC — Suggests continued or revised engagement with a financial advisor, likely for capital markets activities, underscoring the company's reliance on external financing.
• 2024-10-21: Original Engagement Letter with H.C. Wainwright Co., LLC — Marks the initial agreement with a financial institution, setting the stage for potential underwriting or advisory services related to equity offerings.

Glossary

S-1/A

An amendment to an S-1 registration statement filed with the U.S. Securities and Exchange Commission (SEC). It is used to update or correct information previously filed in the original S-1. (This filing is an S-1/A, indicating GRI Bio is amending its initial registration statement, in this case, primarily to update exhibits.)

Placement Agent Warrant

A type of warrant issued to a placement agent (typically an investment bank) as part of the compensation for facilitating a private placement or offering of securities. (GRI Bio has filed forms for Placement Agent Warrants, highlighting compensation structures for capital raising activities.)

Pre-Funded Warrant

A warrant that allows the holder to purchase a share of common stock at a nominal exercise price (often $0.001), effectively representing an immediate share purchase rather than a future option. (The filing of Pre-Funded Warrant forms indicates a mechanism GRI Bio may use in offerings to allow investors to acquire shares without immediate significant cash outlay beyond the purchase price of the warrant itself.)

Series F Warrant

A specific series of warrants, likely issued in a particular financing round (Series F), granting the holder the right to purchase company stock under defined terms. (The inclusion of a Series F Warrant form suggests a recent or planned equity financing round.)

Engagement Letter

A formal agreement between a company and a professional service provider (like an investment bank) outlining the terms, scope, and fees for services to be rendered. (An amendment to the engagement letter with H.C. Wainwright Co., LLC indicates ongoing or modified advisory services, likely related to financing.)

Year-Over-Year Comparison

This S-1/A filing, dated December 9, 2025, is an exhibits-only amendment and does not provide updated financial performance metrics such as revenue, net income, or margins compared to previous filings. The primary changes involve the addition of new warrant forms (Placement Agent, Pre-Funded, and Series F) and an amendment to the engagement letter with H.C. Wainwright Co., LLC. Therefore, a direct comparison of key financial metrics is not possible with this specific filing.

Filing Documents

• gribio-sx1a1.htm (S-1/A) — 156KB
• exhibit1029-sx1a1.htm (EX-10.29) — 76KB
• picture1a.jpg (GRAPHIC) — 5KB
• picture2.jpg (GRAPHIC) — 11KB
• 0001628280-25-056215.txt ( ) — 257KB

EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

ITEM 16. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES. (1) Exhibits. Incorporated by Reference Exhibit No. Description Filed Herewith Form Date File Number 2.1 Agreement and Plan of Merger, by and among the Company, Vallon, and Vallon Merger Sub, Inc., dated as of December 13, 2022. 8-K 121322 001-40034 2.2 Amendment to Agreement and Plan of Merger, by and among the Company, Vallon, and Vallon Merger Sub, Inc., dated as of February 17, 2023. S-4A 022423 333-268977 3.1 Amended and Restated Certificate of Incorporation, as amended. 10-K 031425 001-40034 3.2 Amended and Restated Bylaws . 8-KA 052623 001-40034 4.1 Specimen Common Stock Certificate. S-1 102320 333-249636 4.2 Form of Common Stock Purchase Warrant. 8-K 51322 001-40034 4.3 Form of Amendment No. 1 to Common Stock Purchase Warrant. 8-K 072622 001-40034 4.4 Form of Equity Warrant. 8-K 121322 001-40034 4.5 Form of Exchange Warrant. 8-K 121322 001-40034 4.6 Form of Senior Secured Note of GRI Bio Operations, Inc. S-4 122322 333-268977 4.7 Warrant to Purchase Stock issued to TEP Biotech, LLC, dated as of November 2, 2018. S-4 122322 333-268977 4.8 Warrant to Purchase Stock issued to TEP Biotech, LLC, dated as of December 3, 2019. S-4 122322 333-268977 4.9 Warrant to Purchase Stock issued to TEP Biotech, LLC, dated as of July 7, 2022. S-4 122322 333-268977 4.10 Warrant to Purchase Stock issued to Oppel Greeff, dated as of July 7, 2022. S-4 122322 333-268977 4.11 Form of Amendment to 2022 Warrant to Purchase Stock. S-4A 013023 333-268977 4.12 Form of Series B-1 Common Warrant. S-1A 013124 333-276025 4.13 Form of Series B-2 Common Warrant. S-1A 013124 333-276025 4.14 Form of Placement Agent Warrant . S-1A 062624 333-280323 4.15 Form of Series C-1 Common Warrant. S-1A 062624 333-280323 4.16 Form of Series C-2 Common Warrant. S-1A 062624 333-280323 4.17 Form of Placement Agent Warrant. 8-K 102224 001-40034 4.18 Form of Series D-1 Common Warrant. 8-K 1

SIGNATURES

SIGNATURES Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in La Jolla, California, on this 9th day of December, 2025. GRI BIO, INC. By s W. Marc Hertz, Ph.D. W. Marc Hertz, Ph.D. President and Chief Executive Officer Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed by the following persons in the capacities and on the dates indicated. Signature Title Date s W. Marc Hertz, Ph.D. President, Chief Executive Officer and Director December 9, 2025 W. Marc Hertz, Ph.D. (Principal Executive Officer) * Chief Financial Officer December 9, 2025 Leanne Kelly (Principal Financial and Accounting Officer) * Director and Chairperson of the Board December 9, 2025 David Szekeres * Director December 9, 2025 David Baker * Director December 9, 2025 Roelof Rongen * Director December 9, 2025 Camilla V. Simpson, M.Sc. *By s W. Marc Hertz, Ph.D. W. Marc Hertz, Ph.D. Attorney-in-fact

View Full Filing

View this S-1/A filing on SEC EDGAR