Pfizer Inc. announced overall survival (OS) data from the ARCHER 1050 trial evaluating dacomitinib as a first-line treatment for patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) with EGFR-activating mutations compared to gefitinib. The trial showed a median OS of 34.1 months for patients receiving dacomitinib (95% CI: 29.5, 37.7), representing a more than seven-month improvement compared to 26.8 months with gefitinib (95% CI: 23.7, 32.1).

The OS data from ARCHER 1050 were presented as an oral presentation [Abstract #9004] at the 54th Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago and have been published simultaneously in the Journal of Clinical Oncology.

“Overall survival is an important measure to assess efficacy of investigational compounds. These data presented today are particularly significant as dacomitinib is the first EGFR tyrosine kinase inhibitor in a phase 3 head-to-head study comparing two tyrosine kinase inhibitors to show an improvement in overall survival,” said Professor Tony Mok, Chair of Department of Clinical Oncology, The Chinese University of Hong Kong. “I look forward to having dacomitinib as a potential first-line treatment option for non-small cell lung cancer patients with EGFR-activating mutations.”

Overall survival was a secondary endpoint of ARCHER 1050, a randomized, open label phase 3 study comparing the efficacy and safety of dacomitinib to gefitinib for the first-line treatment of locally advanced or metastatic NSCLC in subjects with EGFR-activating mutations. At the OS data cutoff, median OS was 34.1 months with dacomitinib (95% CI: 29.5, 37.7) compared to 26.8 months with gefitinib (95% CI: 23.7, 32.1). Patients receiving dacomitinib had a 56.2 per cent survival rate at 30 months compared with 46.3 percent for patients who received gefitinib. Subgroup analyses were consistent with the primary OS analysis across most baseline characteristics, including patients with common sub-mutations exon 19 and 21.

The adverse events (AEs) observed with dacomitinib in the study were consistent with findings from previous dacomitinib trials. The most common AEs were diarrhea (87%), nail changes (62%), rash/dermatitis acneiform (49%) and mouth sores (44%). The most common Grade 3 AEs with dacomitinib were rash (14%) and diarrhea (8%). Grade 4 AEs occurred in two percent of dacomitinib-treated patients. There was one case of Grade 5 diarrhea and one case of Grade 5 liver disease. The discontinuation rate due to treatment-related AEs for dacomitinib was 10 per cent compared to seven per cent for gefitinib.

“What is most encouraging about these results is that patients with non-small cell lung cancer harboring EGFR-activating mutations who received dacomitinib achieved a median overall survival of nearly three years, a marked improvement compared to an established treatment in this setting,” said Mace Rothenberg, MD, chief development officer, Oncology, Pfizer Global Product Development. “With today’s podium presentation at the American Society of Clinical Oncology annual meeting and the US Food and Drug Administration Priority Review granted earlier this year, we are encouraged by these data and committed to deliver this promising investigational medicine to patients as quickly as possible.”

In April 2018, the US Food and Drug Administration (FDA) granted priority review for dacomitinib for the first-line treatment of patients with locally advanced or metastatic NSCLC with EGFR-activating mutations. The FDA Prescription Drug User Fee Act (PDUFA) target action date is in September 2018. The European Medicines Agency also accepted the Marketing Authorization Application for dacomitinib for the same indication.

Dacomitinib is an investigational, oral, once-daily, irreversible pan-human epidermal growth factor receptor tyrosine kinase inhibitor (TKI). It has not received regulatory approval in any country.

In 2012, Pfizer and SFJ Pharmaceuticals entered into a collaborative development agreement to conduct ARCHER 1050 across multiple sites.

SFJ Pharmaceuticals is a global drug development company, which provides a unique and highly customized co-development partnering model for the world’s top pharmaceutical and biotechnology companies.