Iniparib

Iniparib

Chemical structure of Iniparib

Iniparib is a small molecule that was investigated as a potential anticancer drug. It was initially thought to be a PARP inhibitor, but subsequent studies suggested that its mechanism of action might be different from other drugs in this class.

Mechanism of Action

Iniparib was originally believed to inhibit poly (ADP-ribose) polymerase (PARP), an enzyme involved in DNA repair. PARP inhibitors are a class of drugs that exploit the concept of synthetic lethality to target cancer cells, particularly those with BRCA1 or BRCA2 mutations. However, further research indicated that Iniparib might not function as a true PARP inhibitor, and its exact mechanism of action remains unclear.

Clinical Development

Iniparib was tested in several clinical trials for the treatment of triple-negative breast cancer (TNBC) and other types of cancer. Early-phase trials showed promising results, leading to its evaluation in larger, randomized studies.

Triple-Negative Breast Cancer

Triple-negative breast cancer is a subtype of breast cancer that lacks estrogen receptor, progesterone receptor, and HER2/neu expression. It is often more aggressive and has fewer treatment options compared to other breast cancer subtypes. Iniparib was studied in combination with chemotherapy agents such as gemcitabine and carboplatin in patients with TNBC.

Results and Challenges

While initial studies suggested potential benefits, subsequent phase III trials did not demonstrate a significant improvement in overall survival or progression-free survival when Iniparib was added to standard chemotherapy regimens. These results led to a reevaluation of its development as a cancer therapeutic.

Current Status

As of the latest updates, Iniparib is not approved for clinical use, and its development has been largely discontinued. The case of Iniparib highlights the challenges in drug development, particularly in understanding the precise mechanisms of action and the importance of robust clinical trial data.

Related Pages

• PARP inhibitor
• Triple-negative breast cancer
• Chemotherapy
• BRCA1
• BRCA2