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CI-1040 (PD184352), a targeted signal transduction inhibitor of MEK (MAPKK)

Lee F Allen1, Judith Sebolt-Leopold, Mark B Meyer

  • 1Department of Cancer Molecular Sciences, Ann Arbor, MI, USA.

Seminars in Oncology
|November 13, 2003
PubMed

Insights

CI-1040, a MEK1/MEK2 inhibitor, shows promise in blocking the extracellular signal-regulated protein kinase (ERK) pathway crucial for cancer growth. Clinical trials indicate good tolerability and antitumor effects, suggesting potential for treating various cancers.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • The mitogen-activated protein kinase (MAPK) or extracellular signal-regulated protein kinase (ERK) cascade is vital for cell growth and differentiation.
  • Aberrant activation of the ERK pathway is implicated in the development and progression of breast and other cancers.
  • Targeting components of this pathway presents a potential therapeutic strategy for cancer treatment.

Purpose of the Study:

  • To evaluate CI-1040 (PD184352), a specific MEK1/MEK2 inhibitor, as a potential anti-cancer therapeutic.
  • To assess the preclinical and clinical efficacy and safety of CI-1040.
  • To investigate the role of MEK inhibition in cancer treatment.

Main Methods:

  • CI-1040, a small-molecule inhibitor of MEK1/MEK2, was administered orally.
  • Preclinical antitumor activity was assessed in various cancer models.
  • Phase I clinical trials were conducted to evaluate safety, pharmacokinetics, and preliminary efficacy, including biomarker studies for target inhibition.

Main Results:

  • CI-1040 effectively inhibited the ERK pathway by blocking ERK phosphorylation (pERK).
  • Preclinical studies demonstrated antitumor activity, particularly in pancreas, colon, and breast cancer models.
  • Phase I trials showed CI-1040 was well-tolerated, allowing continuous dosing, with observed target inhibition and some antitumor responses in patients.

Conclusions:

  • MEK inhibitors, such as CI-1040, represent a promising therapeutic approach for cancers driven by the ERK pathway.
  • CI-1040 demonstrates favorable safety and pharmacokinetic profiles, supporting its further clinical development.
  • Targeting the MEK/ERK pathway could offer significant clinical benefits for patients with breast and other cancers.

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