Milestone Pharmaceuticals has brought in $80 million to fund an at-home, phase 3 clinical trial of its nasal spray for quickly bringing down superhigh heart rates.
Its lead program, etripamil, is a short-acting calcium channel blocker being developed for paroxysmal supraventricular tachycardia, or PSVT, where the heart can beat over 200 times per minute.
While not life-threatening on its own, the condition can cause great distress and anxiety in patients, and lead to trips to the emergency room and the use of intravenous drugs to calm the heart, such as adenosine or verapamil, a channel blocker with the same mechanism of action as etripamil. PSVT events can lead to at least 600,000 claims in the U.S. annually, Milestone estimated.
The equity financing round was led by new backer RTW Investments, with support from Venrock Healthcare Capital Partners and Tavistock Group’s Boxer Capital.
Returning investors included Novo Holdings, Forbion, Domain Associates, BDC Capital, Pappas Capital, GO Capital, Fonds de solidarité FTQ and funds run by Tekla Capital Management. Novo Holdings led the Montreal, Canada-based company’s previous $55 million series C round in 2017.
The latest proceeds will go toward completing the outpatient phase 3 study, which enrolled its first patient in July, as well as a second phase 3 safety study Milestone expects to have up and running in 2019, CEO Joseph Oliveto told FierceBiotech.
The company, which currently counts around 20 employees, also plans on expanding its commercial team, as well as its medical affairs, patient advocacy and late-stage development staff.
In addition, Milestone hopes to conduct signal-finding studies in additional indications for the etripamil spray, such as atrial fibrillation or stable angina. With an effective half-life of about 25 minutes, the company sees etripamil as a safer alternative to IV drugs, and one that can be taken anywhere.
Oliveto described the ongoing trial’s design as a paradigm shift for PSVT investigations, which includes sending patients home with the drug and a small cardiac monitor, and waiting for an event to occur. After self-administering the drug, the cloud-based ECG will aim to capture the conversion from tachycardia to a normal sinus rhythm, and then send the data back to researchers.
“It's a unique way of treating these episodes in the at-home setting, and groundbreaking in terms of how we're going to do this trial,” Oliveto said. Milestone is aiming for about 500 participants and at least 100 events, and is waiting about four to five months before making projections on timelines for completion or regulatory submissions, he added.
It remains to be seen how this at-home drug could be paired with at-home devices, such as the latest version of the Apple Watch with a built-in ECG, or other wearable devices from companies like AliveCor and Fitbit.
“We're hitting late-stage development, and hopefully commercialization, at the time right when these wearables are going to put ECGs on our wrists,” Oliveto said.
That newly available data could be used to help physicians better diagnose the condition, where heart rates can return to normal before a patient can get to an ER or doctor’s office.
“We really want to partner with these companies that are at the forefront developing these wearables, and we're in that process now as we're getting into phase 3,” Oliveto said.