CancerPromising recent clinical trial data for the tyrosine kinase inhibitor (TKI) afatinib (Gilotrif) will strengthen the drug’s position in non-small cell lung cancer (NSCLC) treatment markets outside the US, says an analyst with research and consulting firm GlobalData.

The LUX-Lung 7 trial showed afatinib to reduce the risk of adenocarcinoma progression for patients with epidermal growth factor receptor (EGFR) mutations by 27% compared with one of its closest rivals, AstraZeneca’s gefitinib (Iressa). The differential in progression-free survival at 18 months was 27% for afatinib and 15% for gefitinib, increasing further at 24 months, to 18% and 8%, respectively.

According to Cai Xuan, GlobalData’s analyst covering Oncology and Hematology, these recent trial results suggest that afatinib may have superior long-term efficacy to gefitinib, which will encourage uptake in NSCLC markets in Europe and Asia. “In addition to Gilotrif’s impressive progression-free survival data, more patients responded to Gilotrif treatment than Iressa, with response rates of 70% and 56%, respectively. Despite this, it must be acknowledged that the frequency of serious adverse events was higher for Gilotrif than for Iressa, at rates of 44.4% and 37.1%, respectively. However, the treatment discontinuation rate for both drugs was 6.3%, as reported by Boehringer Ingelheim.”

While afatinib is expected to gain significant market share as a first-line treatment in European and Asian markets which have traditionally favoured gefitinib, the US market will likely continue to be dominated by Genentech/Astellas Pharmaceuticals’ erlotinib (Tarceva).

Xuan explains: “Gilotrif’s lack of success in the US is partially attributable to its lack of clinical superiority and slightly inferior safety profile in comparison to Tarceva. Unlike Tarceva, which is a reversible inhibitor of EGFR, Gilotrif is an irreversible inhibitor of EGFR with slightly increased toxicity. Although no direct comparison data are available for the two drugs, they are viewed to be similar in their clinical efficacy and cost. Thus, with an approval that lagged behind that of Tarceva’s, Gilotrif has not been viewed as a superior option in the first-line EGFR-mutant NSCLC setting.”