Core Insights - Shuttle Pharmaceuticals Holdings, Inc. has executed a non-binding letter of intent to acquire Molecule.ai, an AI-driven company focused on transforming drug discovery and development [1][2] - Molecule.ai utilizes advanced machine learning models, including large language models, to enhance the accuracy and efficiency of evaluating novel molecules, thereby shortening development timelines and reducing costs [3][4] - The acquisition aims to integrate Molecule.ai's innovative platform into Shuttle's operations, enhancing its capabilities in drug-target interaction and autonomous drug discovery workflows [5][9] Acquisition Details - Shuttle will acquire all rights and interests of Molecule.ai, assuming all liabilities, with Molecule.ai having no further obligations post-closing [5][7] - The purchase price for the acquisition is set at $10 million, payable in cash and common shares of Shuttle, contingent upon the completion of certain milestones [7] Molecule.ai's Innovations - Molecule.ai's platform includes features such as rapid evaluation of chemical and biological properties, drug-target interaction modeling, and an autonomous framework for drug discovery workflows [9] - The introduction of the Agentic AI mode will enable AI agents to perform multi-step drug discovery processes, significantly reducing manual effort [6][9] Company Missions - Shuttle Pharmaceuticals focuses on improving outcomes for cancer patients undergoing radiation therapy by developing therapies that enhance the effectiveness of radiation while minimizing side effects [10] - Molecule.ai's mission is to empower researchers with next-generation tools that lower costs and improve efficiency in therapeutic development [8]

Core Insights - Shuttle Pharmaceuticals Holdings, Inc. has executed a non-binding letter of intent to acquire Molecule.ai, an AI company focused on transforming drug discovery and development [1][2]. Company Overview - Shuttle Pharmaceuticals is a specialty pharmaceutical company dedicated to improving cancer treatment outcomes, particularly through radiation therapy [10]. - Molecule.ai, founded by Dr. ZT Zhang, utilizes advanced machine learning and large language models to enhance the drug discovery process [8]. Acquisition Details - The acquisition involves Shuttle acquiring all rights and interests of Molecule.ai, assuming its liabilities, and Molecule.ai will have no further obligations post-closing [5]. - The purchase price for Molecule.ai is set at $10 million, payable in cash and common shares of Shuttle, contingent upon the completion of certain milestones [7]. Technological Advancements - Molecule.ai's platform offers capabilities such as rapid evaluation of chemical properties, drug-target interaction modeling, and an autonomous framework for drug discovery workflows [9]. - The introduction of the Agentic AI mode will automate multi-step drug discovery processes, significantly reducing manual efforts [6][9]. Strategic Vision - The collaboration aims to empower scientists with advanced AI tools to enhance drug discovery and expedite the development of new therapies [4].

Core Viewpoint - Shuttle Pharmaceuticals is making significant progress in its Phase 2 clinical trial of Ropidoxuridine for glioblastoma, with 63% enrollment achieved and 72% of enrolled patients completing all treatment cycles, indicating a well-tolerated therapy [1][6]. Recent Activities - The Phase 2 clinical trial is being conducted in collaboration with leading cancer centers across the U.S. and aims to complete enrollment later this year, with data readouts expected in 2026 [1][3]. - Ropidoxuridine is designed as a radiation sensitizer to improve treatment outcomes for glioblastoma patients, a type of brain cancer with no known cure [1][7]. Clinical Trial Design - The trial involves randomizing 40 patients into two dose levels: 20 patients receiving 1,200 mg/day and 20 patients receiving 960 mg/day, to identify the optimal dose for glioblastoma treatment in combination with radiation therapy [2]. Market Opportunity - Approximately 800,000 patients in the U.S. receive radiation therapy for cancer annually, with 50% treated for curative purposes. The market for radiation sensitizers targets the 400,000 patients treated curatively, expected to grow by over 22% in the next five years [4]. Financial Update - The company ended the quarter with $4.8 million in cash after a private placement that raised $4.25 million in June 2025 [6]. - A reverse stock split was completed in June 2025 as part of a strategic initiative for Nasdaq compliance [6]. Leadership Changes - George Scorsis was appointed as the Chairman of the Board, and Christopher Cooper, the current Interim CEO, was appointed to the Board, both bringing extensive experience in management and finance [6].

Part I. Financial Information [Item 1. Unaudited Condensed Consolidated Financial Statements](index=4&type=section&id=Item%201.%20Unaudited%20Condensed%20Consolidated%20Financial%20Statements) Presents unaudited condensed consolidated financial statements for June 30, 2025, and December 31, 2024, with comprehensive notes [Unaudited Condensed Consolidated Balance Sheets](index=4&type=section&id=Unaudited%20Condensed%20Consolidated%20Balance%20Sheets%20as%20of%20June%2030,%202025%20and%20December%2031,%202024) Unaudited Condensed Consolidated Balance Sheets | | June 30, 2025 | December 31, 2024 | | :------------------------------------------ | :------------ | :---------------- | | **Assets** | | | | Cash and cash equivalents | $4,817,672 | $1,920,144 | | Total current assets | $5,191,917 | $2,210,917 | | Total Assets | $5,504,429 | $2,506,290 | | **Liabilities and Stockholders' Equity** | | | | Accounts payable and accrued expenses | $1,174,374 | $596,600 | | Total current liabilities | $1,692,786 | $1,533,769 | | Total Liabilities | $1,898,910 | $1,797,138 | | Total Stockholders' Equity | $3,605,519 | $709,152 | | Total Liabilities and Stockholders' Equity | $5,504,429 | $2,506,290 | [Unaudited Condensed Consolidated Statements of Operations](index=5&type=section&id=Unaudited%20Condensed%20Consolidated%20Statements%20of%20Operations%20for%20the%20three%20and%20six%20months%20ended%20June%2030,%202025%20and%202024) Unaudited Condensed Consolidated Statements of Operations | Metric | Three Months Ended June 30, 2025 | Three Months Ended June 30, 2024 | Six Months Ended June 30, 2025 | Six Months Ended June 30, 2024 | | :-------------------------------------- | :------------------------------- | :------------------------------- | :----------------------------- | :----------------------------- | | Revenue | $— | $— | $— | $— | | Research and development | $1,025,547 | $645,719 | $2,599,475 | $1,231,823 | | General and administrative | $2,346,323 | $310,038 | $2,943,209 | $634,647 | | Legal and professional | $538,536 | $526,877 | $1,318,963 | $1,001,011 | | Total operating expenses | $3,910,406 | $1,482,634 | $6,861,647 | $2,867,481 | | Net loss from operations | $(3,910,406)$ | $(1,482,634)$ | $(6,861,647)$ | $(2,867,481)$ | | Total other income (expense) | $203,941 | $(548,581)$ | $102,175 | $(894,765)$ | | Net loss | $(3,706,465)$ | $(2,031,215)$ | $(6,759,472)$ | $(3,762,246)$ | | Net loss per shares - basic and diluted | $(3.29)$ | $(24.12)$ | $(8.82)$ | $(44.98)$ | [Unaudited Condensed Consolidated Statements of Changes in Stockholders' Equity](index=6&type=section&id=Unaudited%20Condensed%20Consolidated%20Statements%20of%20Changes%20in%20Stockholders'%20Equity%20for%20the%20three%20and%20six%20months%20ended%20June%2030,%202025%20and%202024) For the Six Months Ended June 30, 2025 | | Shares | Common Stock Amount | Additional Paid-In Capital | Accumulated Deficit | Total Stockholders' Equity | | :------------------------------------------------ | :------- | :------------------ | :------------------------- | :------------------ | :------------------------- | | Balance at December 31, 2024 | 163,093 | $2 | $35,287,251 | $(34,578,101)$ | $709,152 | | Issuance of common stock and pre-funded warrants, net | 53,637 | $1 | $5,038,573 | — | $5,038,574 | | Stock-based compensation | — | — | $537,046 | — | $537,046 | | Net loss | — | — | — | $(3,053,007)$ | $(3,053,007)$ | | Balance at June 30, 2025 | 1,070,773 | $11 | $44,943,081 | $(41,337,573)$ | $3,605,519 | For the Six Months Ended June 30, 2024 | | Shares | Common Stock Amount | Additional Paid-In Capital | Accumulated Deficit | Total Stockholders' Equity | | :------------------------------------------------ | :------- | :------------------ | :------------------------- | :------------------ | :------------------------- | | Balance at December 31, 2023 | 80,348 | $1 | $29,489,074 | $(25,433,304)$ | $4,055,790 | | Stock-based compensation | — | — | $111,449 | — | $111,449 | | Net loss | — | — | — | $(1,731,031)$ | $(1,731,031)$ | | Balance at June 30, 2024 | 84,250 | $21 | $29,996,983 | $(29,195,550)$ | $801,454 | [Unaudited Condensed Consolidated Statements of Cash Flows](index=7&type=section&id=Unaudited%20Condensed%20Consolidated%20Statements%20of%20Cash%20Flows%20for%20the%20six%20months%20ended%20June%2030,%202025%20and%202024) Unaudited Condensed Consolidated Statements of Cash Flows | Cash Flow Activity | Six Months Ended June 30, 2025 | Six Months Ended June 30, 2024 | | :-------------------------------------- | :----------------------------- | :----------------------------- | | Net cash used in operating activities | $(5,881,979)$ | $(2,638,425)$ | | Net cash provided by investing activities | $— | $1,259,270 | | Net cash provided by (used in) financing activities | $8,779,507 | $(501,667)$ | | Net change in cash and cash equivalents | $2,897,528 | $(1,880,822)$ | | Cash and cash equivalents, end of period | $4,817,672 | $695,594 | [Notes to Unaudited Condensed Consolidated Financial Statements](index=9&type=section&id=Notes%20to%20Unaudited%20Condensed%20Consolidated%20Financial%20Statements) Provides detailed explanations and disclosures supporting the unaudited condensed consolidated financial statements, covering organization, liquidity, accounting policies, and financial instruments [Note 1 – Organization and Liquidity](index=9&type=section&id=Note%201%20%E2%80%93%20Organization%20and%20Liquidity) Shuttle Pharmaceuticals, a cancer therapy developer, faces substantial going concern doubt, with current funds insufficient for operations and clinical trials - The Company's primary purpose is to develop and commercialize unique drugs for the sensitization of cancers and protection of normal tissues, aiming to improve outcomes for cancer patients receiving radiation therapy[18](index=18&type=chunk) - Shuttle's Ropidoxuridine product candidate, used with radiation therapy to sensitize cancer cells, was initially funded by an NCI SBIR contract and further developed through collaborations with the University of Virginia[18](index=18&type=chunk) - The Company has incurred losses since inception, with a net loss of approximately **$6.8 million** and no revenues for the six months ended June 30, 2025, and working capital of approximately **$3.5 million** as of June 30, 2025[21](index=21&type=chunk) - Despite recent equity raises (**$5.0 million** net in March 2025, **$3.9 million** net in June 2025) and a **$2.0 million** revolving note, existing cash resources are not expected to provide sufficient funds to carry out operations and clinical trials through the next twelve months[22](index=22&type=chunk) - The Company's ability to continue as a going concern is dependent upon its ability to successfully raise additional equity or debt financing[23](index=23&type=chunk) [Note 2 – Summary of Significant Accounting Policies](index=10&type=section&id=Note%202%20%E2%80%93%20Summary%20of%20Significant%20Accounting%20Policies) Outlines significant accounting policies, including basis of presentation, impact

As filed with the Securities and Exchange Commission on August 4, 2025 Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 SHUTTLE PHARMACEUTICALS HOLDINGS, INC. (Exact name of registrant as specified in its charter) If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the ...

Core Viewpoint - Shuttle Pharmaceuticals Holdings, Inc. has successfully closed a private placement, raising $4.25 million to support its operations and potential acquisitions [1][2]. Group 1: Financial Details - The company issued 1,180,877 shares of common stock at a purchase price of $3.60 per share, in accordance with Nasdaq rules [2]. - The gross proceeds from the offering amount to $4.25 million, which will be utilized for acquisitions, marketing, and general corporate purposes [1]. Group 2: Company Overview - Shuttle Pharmaceuticals is focused on enhancing outcomes for cancer patients undergoing radiation therapy by developing therapies that maximize the effectiveness of radiation while minimizing side effects [6]. - The company's mission includes increasing cancer cure rates, prolonging patient survival, and improving quality of life through the development of radiation sensitizers [6].

Group 1 - Shuttle Pharmaceuticals Holdings, Inc. has entered into a securities purchase agreement with an accredited investor for gross proceeds of $4.25 million, intended for acquisitions, marketing, and general corporate purposes [1][2]. - The company will issue 1,180,877 shares of common stock at a purchase price of $3.60 per share, with the offering expected to close around June 23, 2025 [2][3]. - WestPark Capital, Inc. is acting as the exclusive placement agent for the offering, with additional details to be filed in a Form 8-K with the SEC [3]. Group 2 - Shuttle Pharmaceuticals is focused on improving outcomes for cancer patients treated with radiation therapy by developing therapies that enhance the effectiveness of radiation while minimizing side effects [6]. - The company's mission includes increasing cancer cure rates, prolonging patient survival, and improving quality of life through the development of radiation sensitizers [6].

Group 1 - Shuttle Pharmaceuticals Holdings, Inc. will implement a reverse stock split effective June 16, 2025, at 12:01 a.m. Eastern Time, with the common stock continuing to trade under the symbol "SHPH" on Nasdaq [1][2] - The reverse stock split will convert every 25 shares of the Company's common stock into 1 share, reducing the total number of outstanding shares from approximately 26,210,037 to about 1,048,401 shares [2] - This action is part of Shuttle's strategic plan to comply with Nasdaq's continued listing requirements and to strengthen the Company's long-term capital structure [3] Group 2 - Shuttle Pharmaceuticals is focused on improving outcomes for cancer patients undergoing radiation therapy by developing therapies that enhance the effectiveness of radiation while minimizing side effects [4] - The Company aims to increase cancer cure rates, prolong patient survival, and improve quality of life through the development of radiation sensitizers, which can be used alone or in combination with other treatments [4]

Core Viewpoint - Shuttle Pharmaceuticals Holdings, Inc. has announced a proposed reverse stock split of its common stock at a ratio of 25-for-1, subject to Nasdaq approval, aimed at maintaining compliance with listing requirements and strengthening its capital structure [1][3]. Group 1: Reverse Stock Split Details - At the effective time of the reverse stock split, every 25 shares of the Company's common stock will be combined into 1 share, reducing the total number of shares from 26,210,037 to approximately 1,048,401 shares [2]. - The reverse stock split will also apply to common stock issuable upon the exercise of outstanding RSU grants and warrants, with no fractional shares issued; fractional entitlements will be rounded up to the next highest whole number [2]. Group 2: Company Overview - Shuttle Pharmaceuticals is a discovery and development stage specialty pharmaceutical company focused on improving outcomes for cancer patients treated with radiation therapy [4]. - The Company's mission is to enhance the effectiveness of radiation therapy while minimizing side effects, aiming to increase cancer cure rates, prolong patient survival, and improve quality of life [4].

Core Viewpoint - Shuttle Pharmaceuticals Holdings, Inc. has appointed George Scorsis as the Chairman of the Board of Directors, bringing extensive experience in leading companies in regulated industries to rapid growth [1][2]. Company Overview - Shuttle Pharmaceuticals is a discovery and development stage specialty pharmaceutical company focused on enhancing outcomes for cancer patients undergoing radiation therapy (RT) [4]. - The company's mission is to develop therapies that maximize the effectiveness of RT while minimizing side effects, aiming to increase cancer cure rates, prolong patient survival, and improve quality of life [4]. Leadership Experience - George Scorsis has over 25 years of experience in various industries, including alcohol, energy drinks, and biotech, with notable positions such as President at Mettrum Health Corp. and CEO of Liberty Health Sciences [2]. - He currently holds chairmanship roles at Entourage Health Corp. and AWAKN Life Sciences, both publicly traded [2]. Strategic Vision - Scorsis expressed his commitment to leveraging the company's radiation sensitizers to improve cancer treatment outcomes, particularly for glioblastoma patients, aiming to enhance cure rates and patient quality of life [3].