Company: SHPH
Filing Date: 2025-02-27
Form Type: 424B3
Source: 0001493152-25-008476
Chunk: 17

Company: Shuttle Pharmaceuticals Holdings, Inc.
Filing Date: 2025-02-27
Form: 424B3
Chunk 17
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ancer agents for cancer therapy. Vorinostat and romidepsin have been approved by the FDA for treatment of patients with relapsed or refractory T-cell lymphomas. In addition, panobinostat received FDA approval for treatment of recurrent multiple myeloma in combination with bortezomib and dexamethasone.

In preclinical studies, SP-1-161 inhibited the activity of pan-HDACs and activated the ATM gene product. ATM is a critical protein for the activation of the cell stress response for cellular recovery from radiation exposure in normal cells, but not in cancer cells. ATM activates the P53 protein, referred to as the “guardian of the genome,” and serves as a tumor suppressor critical for normal cell function and activation of programmed cell death in cancer cells.

In preclinical studies, SP-1-161 protected normal breast epithelial cells (184A1) following exposure to ionizing radiation while increasing sensitivity of breast cancer cells (MCF7). SP-1-161 provides this dual function in a single molecule and this molecule is differentiated from other HDAC inhibitors by treatment of cancers while protecting normal cells. ( SeeGrindrod S, Brown M, Jung M. “Development of dual Function Small Molecules as Therapeutic Agents for Cancer Research,” Poster presentation #A178, American Association of Cancer Research Oct 2017).

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SP-2-225

SP-2-225 is a selective HDAC inhibitor that affects histone deacetylase (HDAC6) and is a member of the class IIb HDAC family. Class II HDACs play important roles in cancer motility, invasion, neurological diseases, and immune checkpoint. HDAC6 inhibition has been most extensively studied for its role in the treatment of hematological cancers. HDAC6 is unique among HDAC enzymes in having two active catalytic domains and a unique physiological function. In addition to the modification of histones, HDAC6 targets specific substrates including α-tubulin and HSP90, and are involved in protein trafficking and degradation, cell shape and migration. Selective HDAC6 inhibitors are an emerging class of pharmaceuticals due to the involvement of HDAC6 in pathways related to neurodegenerative diseases, cancer and immunology. Specifically, its potential to affect regulation of the immune system and enhance the immune response in cancer is of great interest. With the introduction of check-point inhibitors, CAR-T therapies and personalized medicine in cancer, regulation of the immune response