Joshua Bauml, MD of the University of Pennsylvania discusses Osimertinib versus Erlotinib or Gefitinib in the FLAURA Trial. Osimertinib did very well in the FLAURA study for those patients with T790M mutation after progression on the first or second generation Tyrosine-kinase inhibitor (TKI). In the FLAURA study, Osimertinib is compared with either erlotinib or gefinitib and what transpired was a marked prolongation of the progression-free survival and these curves separated very early.
Another most interesting thing is the trend, although not very statistically significant, but it seems there is an improvement in the overall survival, as well. Resistance mutations to targeted therapy are present earlier in the diagnosis of patients. So, those patients who develop small-cell transformation are more likely to harbour P53 and RB mutation at the time of diagnosis. The administration of Osimertinib in the first-line prevents expansion of these and limits the genetic hydrogenating.
Osimertinib is also better tolerated than erlotinib, gefitinib or afatinib. And, if these will be compared to dacomitinib, which was evaluated for the Phase III setting compared to first generation TKI inhibitors, although there was an improved outcome, but it was having an increase in toxicity. Osimertinib has improved PFS and less toxicity.