Company: MDCXW
Filing Date: 2025-11-19
Form Type: S-1
Source: 0001062993-25-016962
Chunk: 93

Company: Medicus Pharma Ltd.
Filing Date: 2025-11-19
Form: S-1
Chunk 93
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 cell carcinoma is the most common cancer in humans, with an estimated annual incidence in the United States of 5.4 million cases (American Cancer Society). BCC arises from the basal cells in the epidermis and is associated with both chronic and intermittent acute UV exposure. The development of basal cell carcinoma is thought to be attributable, in part, to a deregulation of the Hedgehog signaling pathway. The Hedgehog pathway is involved in stem cell maintenance, regulation of cell proliferation and differentiation, and carcinogenesis. Unregulated activation has been implicated in the development of multiple cancers, including BCC (Gupta et. al. 2010). Chemotherapeutic inhibition of Hedgehog signaling has been demonstrated to be effective against advanced BCC (Soura et. al. 2015).

The current standard of care for localized BCC is surgical, either via standard excision or Mohs micrographic surgery; but it carries risks, including bleeding, scarring, and infection. Surgical treatment may not be desirable or indicated for all patients, resulting in a demand for more non-surgical treatment options.

Commonly used topical treatments for BCC currently include: imiquimod; 5-fluorouracil; and tazarotene.

Imiquimod works primarily by acting as an agonist of toll-like receptors 7 and 8 (Schon and Schon, 2007) leading to activation of nuclear factor-kappa B. This activation results in the induction of pro-inflammatory cytokines and chemokines, ultimately resulting in a T-cell-mediated anti-tumor immune response (Schon and Schon, 2007). Imiquimod has demonstrated efficacy in the treatment of both superficial and nodular BCC; however, imiquimod's efficacy is significantly inferior to surgery, with 84% of imiquimod-treated patients remaining tumor-free after 3-years, compared to 98% of surgically treated patients (Bath-Hextall et. al. 2014).

5-Fluorouracil is an antimetabolite that blocks DNA replication by inhibiting thymidylate synthase (Nakamura et. al. 2014). Three-year tumor-free status following treatment with fluorouracil is poorer than with imiquimod, with 68% of patients remaining tumor-free after 3-years (Roozeboom et. al. 2016).

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Tazarotene's