Edgewise Therapeutics has unveiled early safety data for its rare heart disease drug, with results suggesting it could do away with a black box warning seen with Bristol Myers Squibb’s Camzyos in obstructive hypertrophic cardiomyopathy (HCM).
Edgewise’s candidate, dubbed EDG-7500, also shows signs of having a relatively better side effect profile than Cytokinetics’ aficamten in HCM.
On Thursday morning, Edgewise said that in two trials that separately tested the drug in HCM patients and healthy volunteers, none of the participants saw a drop in left ventricular ejection fraction (LVEF) below 50% across a “broad range” of doses. LVEF refers to how much blood is being pumped out of the heart’s left ventricle. Ejection fraction below 40% means that the heart isn’t pumping enough blood and can be a sign of heart failure.
Ahead of Edgewise’s data release, Leerink analysts wrote Wednesday that if the results suggest a better risk-benefit profile than Camzyos, Edgewise could win approval without a risk evaluation and mitigation strategy (REMS) and with a more simplified dosing regimen, which would enable uptake among a greater number of HCM patients.
Investors had an unintentional preview of Thursday’s results. An abstract for the Heart Failure Society of America’s annual meeting showcasing EDG-7500 was briefly published early on Tuesday on the conference website and distributed on social media. Nonetheless, the company’s share price $EWTX was up 45% on Thursday.
But Edgewise is behind in the HCM race. Camzyos was approved in 2022 and it collected $231 million in sales last year. Cytokinetics is set to put forward its candidate to the FDA soon with an eye to launching its drug next year. Edgewise’s safety data are from a Phase 1 trial with 72 healthy volunteers and part one of a Phase 2 trial in HCM, which enrolled 11 patients with obstructive HCM.
Camzyos carries a black box warning that cautions a drop in LVEF. In the Phase 3 EXPLORER-HCM trial, nine Camzyos patients had to pause dosing because of the side effect, although eight of them later resumed treatment at a lower dose after recovery.
Leerink analysts said Thursday that Edgewise’s data also appear to be differentiated from aficamten. There were instances of LVEF drops below 50% in early studies of Cytokinetics’ drug, while new data show Edgewise’s candidate doesn’t, they added. Patients dosed with aficamten in a registrational trial had an average 4.8% drop in LVEF from baseline compared with placebo but with no associated dose interruptions.
Edgewise CEO Kevin Koch told Endpoints News in an email that cardiac myosin inhibitors such as Camzyos and aficamten may be on-off switches for myosin, while EDG-7500, which is a cardiac sarcomere modulator, is more about controlling the rate of interaction. With the company’s more controlled approach, there may be fewer side effects, he added.
As for next steps, Edgewise has started the next part of its Phase 2 trial, which is testing EDG-7500 in obstructive and non-obstructive HCM patients with data expected early next year. In May, Cytokinetics CEO Robert Blum told Endpoints that aficamten could be suitable for a “broader array” of obstructive HCM patients compared with Camzyos.
Edgewise said in the presentation it is “well-capitalized to execute important milestones,” with $512 million in cash, equivalents and marketable securities as of the end of June. This should support the company’s activities through 2027.