Panitumumab Monotherapy as a Second-line Treatment in Metastasised Colorectal Cancer: A Single Centre Experience

Ponatinib: a novel multi-tyrosine kinase inhibitor against human malignancies

Human malignancies are often the result of overexpressed and constitutively active receptor and non-receptor tyrosine kinases, which ultimately lead to the mediation of key tumor-driven pathways. Several tyrosine kinases (ie, EGFR, FGFR, PDGFR, VEGFR), are aberrantly activated in most common tumors, including leukemia, glioblastoma, gastrointestinal stromal tumors, non-small-cell lung cancer, and head and neck cancers. Iclusig™ (ponatinib, previously known as AP24534) is an orally active multi-tyrosine kinase inhibitor and is currently approved by the US Food and Drug Administration for patients with chronic myeloid leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia, specifically targeting the BCR-ABL gene mutation, T315I. Due to ponatinib's unique multi-targeted characteristics, further studies have demonstrated its ability to target other important tyrosine kinases (FGFR, PDGFR, SRC, RET, KIT, and FLT1) in other human malignancies. This review focuses on the available data of ponatinib and its molecular targets for treatment in various cancers, with a discussion on the broader potential of this agent in other cancer indications.

The efficacy and safety of panitumumab in the treatment of patients with metastatic colorectal cancer: a meta-analysis from five randomized controlled trials

Background

The efficacy of adding panitumumab to chemotherapy remains controversial in the treatment of metastatic colorectal cancer (mCRC). Thus, we conducted this meta-analysis to assess the efficacy and safety of this combination regimen in patients with mCRC.

Methods

The PubMed, Embase, and Web of Science databases were comprehensively searched. Eligible studies included randomized controlled trials (RCTs) that estimated the efficacy of panitumumab with or without chemotherapy in the treatment of patients with mCRC. Hazard ratio (HR), risk ratio (RR), and 95% confidence intervals (CIs) were calculated, and heterogeneity was tested using I² statistics.

Results

Four studies involving a total of 3,066 patients were included in this meta-analysis. The addition of panitumumab to chemotherapy significantly improved progression-free survival (PFS) (HR =0.84, 95% CI =0.78–0.91, P=0.000) and the objective response rate (ORR) (RR =2.18, 95% CI =1.13–4.22, P=0.021) compared to chemotherapy alone, but no effect was noted on overall survival (OS) (HR =0.97, 95% CI =0.89–1.05, P=0.402). Subgroup analysis based on KRAS gene status revealed that the combined therapy significantly improved PFS (HR =0.71, 95% CI =0.57–0.88, P=0.002) and ORR (RR =2.43, 95% CI =1.21–4.90, P=0.013) in patients with wild-type KRAS tumors. Irinotecan-based chemotherapy plus panitumumab significantly prolonged PFS in patients with mCRC (HR =0.84, 95% CI =0.76–0.94, P=0.002). The combined treatment also increased the incidence of grade 3/4 adverse events.

Conclusion

This meta-analysis indicates that the combination of panitumumab and chemotherapy effectively improved PFS and ORR, but it did not prolong OS. However, as the number of studies in the meta-analysis was limited, more large-scale, better-designed RCTs are needed to assess the combination of panitumumab and chemotherapy.