Top-line midstage data out of Cytokinetics, under pressure to perform after losing a Big Pharma partner and after recent setbacks, are good enough for the biotech to kick-start a phase 3 later this year.
The trial was for its experimental heart drug CK-274 an oral, small molecule cardiac myosin inhibitor that is targeting hypertrophic cardiomyopathy (HCM), which is most often caused by abnormal genes in the heart muscle that cause the walls of the heart chamber (left ventricle) to contract harder and become thicker than normal.
The thickened walls become stiff. This reduces the amount of blood taken in and pumped out to the body with each heartbeat.
The topline data from the so-called REDWOOD-HCM phase 2 showed patients using CK-274 for 10 weeks resulted in “substantial and statistically significant reductions” from baseline compared to placebo in the average resting left ventricular outflow tract pressure gradient (LVOT-G) and the average post-Valsalva LVOT-G, compared to placebo.
The majority of patients treated with CK-274 (78.6% in one part of the test and 92.9% in the second) hit the target goal of treatment defined as resting gradient and post-Valsalva gradient after 10 weeks, again against placebo.
Cytokinetics said the drug “was well tolerated” with “no serious adverse events attributed to CK-274 and no treatment interruptions occurred on CK-274,” with no new cases of atrial fibrillation reported.
The trial was set up predominately to “inform dose selection and support progression” of CK-274 to phase 3 registrational clinical trial, which is expected to start before year-end. More details from the trial will be shared later this year.
This pits it against Bristol Myers Squibb and its recent $13.1 billion buyout of MyoKardia and its drug, mavacamten, which is zeroing in on non-obstructive HCM, and other indications.
This is a needed win for the company after both Astellas and Amgen have dropped partnerships with the biotech this year: The former culling a muscle disease research pact with Cytokinetics two years after a partnered med between the two flopped in a midstage test; the latter was more serious, as Amgen canceled a 14-year tie-up for heart drug omecamtiv mecarbil, which has hit trial goals, but come up short in key areas, leading to Amgen bailing.
Omecamtiv mecarbil is a selective cardiac myosin activator designed to target the contractile mechanisms of the heart and boost contraction, and works in a similar way to CK-274, though it sees the latter as “next generation.”
The biotech's shares were up 50% premarket Monday morning.