Company: SHPH
Filing Date: 2025-02-26
Form Type: 10-K
Source: 0001493152-25-008300
Chunk: 5

Company: Shuttle Pharmaceuticals Holdings, Inc.
Filing Date: 2025-02-26
Form: 10-K
Item: Item 1
Chunk 5
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idoxuridine
    and Tipiracil (IPdR/TPI) is a new combination formulation demonstrating extended bioavailability
    after oral administration in an animal model system. The IPdR/TPI formulation will undergo preclinical development for use as a radiation
    sensitizer and represents a “next generation” drug product for clinical evaluation.

    ●
    SP-2-225
    is Shuttle Pharma’s pre-clinical class IIb selective HDAC inhibitor that selectively affects histone deacetylase HDAC6.
    SP-2-225 has effects on the regulation of the immune system. The interactions of RT with the immune response for cancer treatment
    are of great current interest, offering insight into potential mechanisms for primary site and metastatic cancer treatment. For this
    reason, Shuttle Pharma has selected SP-2-225 as the candidate lead HDAC inhibitor for preclinical development. We have contracted
    with investigators at Georgetown University to perform preclinical studies of immune activation after radiation therapy in an animal
    tumor model. With the introduction of check-point inhibitors, CAR-T therapies and personalized medicine in cancer, regulation of
    the immune response following RT is of significant clinical and commercial interest.

    ●
    SP-1-303
    is Shuttle Pharma’s pre-clinical selective Class I HDAC inhibitor that preferentially affects histone deacetylases
    HDAC1 and HDAC3 members of the class I HDAC family of enzymes. SP-1-303 data show direct cellular toxicity in ER positive breast
    cancer cells. Furthermore, SP-1-303 increases PD-L1 expression. A manuscript reporting completed preclinical in vitro studies is
    in preparation. We plan to seek collaborations to complete SP-1-303 pre-clinical development in 2025.

Our
Approach

We
believe that we have established a leadership position in radiation sensitizer discovery and development. Over approximately seven years
of research, we have identified two clinical phase product candidates and discovered new pre-clinical molecules using our proprietary
platform technologies to increase the therapeutic index for patients receiving radiation for treatment of solid tumors. Our development
strategy has four key pillars: (1) to improve the efficacy of RT by demonstrating improved disease-free survival rates in patients who
undergo radiation therapy, (2) reduce the amount of radiation needed for a favorable tumor response, thereby limiting the potential for
radiation related toxicities to healthy cells, (3) decrease the