Company: SHPH
Filing Date: 2025-01-24
Form Type: 424B3
Source: 0001493152-25-003508
Chunk: 85

Company: Shuttle Pharmaceuticals Holdings, Inc.
Filing Date: 2025-01-24
Form: 424B3
Chunk 85
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 ACOs. To address the quality of care measures designated by CMS and to gain additional incentives, use of clinical pathways or treatment guidelines is anticipated to be increasingly instituted to manage patient care. The impact on the uptake of new products in this environment can be profound if the new product is first in class and is included in national guidelines from organizations such as the NCCN and/or approval by the regional CMS contracting groups.

ROPIDOXURIDINE

The halogenated thymidine (TdR) analogs, bromodeoxyuridine (BUdR) and iododeoxyuridine (IUdR), are a class of pyrimidine analogs that have been recognized as potent radiosensitizing agents since the early 1960s. ( SeeKinsella TJ. An Approach to the Radiosensitization of Human Tumors. Cancer J Sci Am.Jul-Aug 1996:2(4); 184-193). Their cellular uptake and metabolism are dependent on the TdR salvage pathway where they are initially phosphorylated to the monophosphate derivative by the rate-limiting enzyme, thymidine kinase (TK). ( SeeShewach DS, Lawrence TS. Antimetabolite radiosensitizers. J Clin Oncol,Sep 10 2007; 25(26):4043-4050). After sequential phosphorylation to triphosphates, they are then used in DNA replication, in competition with deoxythymidine triphosphate (dTTP), by DNA polymerase. DNA incorporation is a prerequisite for radiosensitization of human tumors by the halogenated TdR analogs, and the extent of radiosensitization correlates directly with the percentage TdR replacement in DNA. ( SeeLawrence TS, Davis MA, Maybaum J, Stetson PL, Ensminger WD. The Dependence of Halogenated Pyrimidine Incorporation and Radiosensitization on the Duration of Drug Exposure. International Journal of radiation oncology, biology, physics.Jun 1990; 18(6);1393-1398). The molecular mechanisms of radiosensitization are most likely the result of increased susceptibility of TdR analog-substituted DNA to the generation of highly reactive uracil free radicals by ionizing radiation (IR), which may also damage unsubstituted complementary-strand DNA. Repair of IR damage may also be reduced by pre-IR exposure to these analogs.

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