Milestone Pharmaceuticals reported highly positive data from its Phase III RAPID trial of etripamil in paroxysmal supraventricular tachycardia (PSVT) patients.
Milestone Pharmaceuticals reported highly positive data on Monday from the Phase III RAPID trial of etripamil, its inhalable calcium channel blocker in paroxysmal supraventricular tachycardia (PSVT).
An earlier study missed the mark, but the new research supports regulatory submissions worldwide.
PVST is marked by intermittent periods of a rapid heartbeat and can be linked with symptoms including palpitations, sweating, chest pressure or pain, shortness of breath, sudden fatigue, dizziness, fainting and anxiety. The goal of etripamil is for patients to manage their symptoms at home.
Traditional treatments include oral beta-blockers, calcium channel blockers, catheter ablation, and vagal maneuvers. Other therapies include intravenous drugs such as adenosine. At worst, it is treated with defibrillation paddles.
Joseph Oliveto, president and CEO of Milestone, said in a press conference that the company was “thrilled with positive outcomes.” It also “looks forward to reviewing the data.” He further noted that there were 2 million patients who experienced PVSD in the U.S. alone.
The study data, Oliveto said, supported the drug for regulatory submissions in PVST episodes “wherever or whenever they occur.”
The RAPID trial enrolled 706 patients in North America and Europe. The patients were randomized 1:1 for a nasal spray of either etripamil or placebo without medical monitoring. Patients who did not receive symptom relief within 10 minutes of the initial dose were told to give themselves a second dose.
The trial hit the primary endpoint, what Oliveto described as a “statistically significant and clinically meaningly decrease in time to PSVT conversion over the first 30 minutes compared to placebo.” In addition, the drug’s “safety and tolerability findings were particularly important.”
In addition, the study indicated a “43% decrease in medical interventions and a 39% reduction in emergency department visits,” Bharucha said.
Lorenz Muller, Milestone’s chief commercial officer (CCO), indicated the company’s analysis suggested there were 2.6 million patients in the U.S. and that there would likely be “1 to 1.6 million addressable patients.”
The company’s data indicated the typical PVST patient had 12 to 15 episodes per year, which would break down into 2.5 million to 4.0 million episodes annually. If approved, this presents $2 to $3 billion per year of potential annual sales of the drug.
“The drug has to be safe for physicians to be comfortable with patients treating themselves at home and this study supported that,” Muller added.
Oliveto indicated the company planned to immediately begin talks with the FDA with expectations of filing a New Drug Application in mid-2023 based on the agency’s feedback.
A Long-Awaited Comeback for Etripamil
In March 2020, Milestone reported data from the NODE-301 trial of etripamil nasal spray in PSVT. That study failed to hit the primary endpoint of time to conversion of SVT to sinus rhythm compared to placebo over a five-hour period after receiving the drug.
The study demonstrated statistically significant improvements in favor of the drug over placebo in the secondary endpoint of patient-reported treatment satisfaction. There was also a trend in improvement in the percentage of patients looking for medical intervention, including visiting the emergency department.
In Monday’s conference call, the company noted that the earlier study was conducted very early in the COVID-19 pandemic when many healthcare institutions and emergency departments were limiting visits, which is likely why the rate of medical interventions in the placebo group was so low.
