Mast cells
The US Food and Drug Administration (FDA) has granted priority review for the new drug application for midostaurin (PKC412) as a treatment for advanced systemic mastocytosis (SM) and newly diagnosed, FLT3-mutated acute myeloid leukemia (AML).
The FDA has also accepted for review the premarket approval application for the midostaurin FLT3 companion diagnostic, which is designed to help identify patients who may have a FLT3 mutation and could potentially benefit from treatment with midostaurin.
Midostaurin is being developed by Novartis. The companion diagnostic is being developed by Novartis and Invivoscribe Technologies, Inc.
About priority review
The FDA grants priority review to applications for therapies that may provide significant improvements in the treatment, diagnosis, or prevention of serious conditions.
The agency’s goal is to take action on a priority review application within 6 months of receiving it. The goal in the standard review process is to take action within 10 months.
About midostaurin
Midostaurin is an oral, multi-targeted kinase inhibitor. The drug was granted breakthrough therapy designation by the FDA earlier this year for newly diagnosed, FLT3-mutated AML.
According to Novartis, the new drug application submission for midostaurin includes data from the largest clinical trials conducted to date in advanced SM and newly diagnosed, FLT3-mutated AML.
Midostaurin in AML
In the phase 3 RATIFY trial, researchers compared midostaurin plus standard chemotherapy to placebo plus standard chemotherapy in adults younger than 60 with FLT3-mutated AML. Results from this trial were presented at the 2015 ASH Annual Meeting.
Patients in the midostaurin arm experienced a statistically significant improvement in overall survival, with a 23% reduction in risk of death compared to the placebo arm (hazard ratio=0.77, P=0.0074).
There was no significant difference in the overall rate of grade 3 or higher hematologic and non-hematologic adverse events in midostaurin arm and the placebo arm. Similarly, there was no significant difference in treatment-related deaths between the arms.
Midostaurin in SM
Data from the phase 2 study of midostaurin in patients with advanced SM were published in NEJM in June.
The drug produced a 60% overall response rate, and the median duration of response was 24.1 months.
Fifty-six percent of patients required dose reductions due to toxic effects, but 32% of these patients were able to return to the starting dose of midostaurin.
Access to midostaurin
Since midostaurin remains investigational, both within the US and globally, Novartis opened a Global Individual Patient Program (compassionate use program) and, in the US, an Expanded Treatment Protocol, to provide access to midostaurin for eligible patients with newly diagnosed AML and advanced SM.
Physicians who want to request midostaurin for eligible patients can contact a Novartis medical representative in their respective countries. In the US, physicians can call 1-888-NOW-NOVA (1-888-669-6682) for more information.
