Cytokinetics, Inc announced that data relating to patient baseline characteristics and the reasons for patient screen failure, both from the first cohort of the Phase 2 clinical trial of CK-2127107 in spinal muscular atrophy (SMA), were presented at the Cure SMA 2017 Annual SMA Conference in Orlando, FL by Stacy Rudnicki, M.D., Director, Clinical Research at Cytokinetics. In collaboration with Astellas Pharma Inc.Cytokinetics is developing CK-2127107 as a potential treatment for people living with SMA and certain other debilitating diseases and conditions associated with skeletal muscle weakness and/or fatigue.
Patients enrolled in Cohort 1 of this Phase 2, hypothesis-generating, double-blind, randomized, placebo-controlled clinical trial were on average 27.7 years of age and had symptom onset 22.2 years prior to enrollment (SD: 12.25) with a confirmed diagnosis 11.6 years before enrollment (SD: 6.25). Of the 39 patients enrolled in Cohort 1, 54 percent were male; 19 patients were ambulatory (all with SMA Type III), and 20 patients were non-ambulatory (five with Type II and 15 with SMA Type III). With respect to respiratory measurements, patients had on average a forced vital capacity (FVC) of 84 percent of predicted (min, max: 42, 127), a maximal expiratory pressure (MEP) of 88.7 cm H2O (min, max: 34, 196), and a maximal inspiratory pressure (MIP) of -99.4 cm H2O (min, max: -228, -29).
In terms of motor measurements at baseline, ambulatory patients had an average score of 48.8 (min, max: 37, 54) in the Hammersmith Functional Motor Scale Expanded (HFMSE), 39.2 (min, max: 26, 41) in the Revised Upper Limb Module (RULM), 17.7 (min, max: 9, 35) seconds in the timed-up-and-go, and 290.7 (min, max: 138, 426) meters in the six-minute walk. Non-ambulatory patients scored 18.9 (min, max: 10, 50) in the HFMSE, and 28.0 (min, max: 17, 41) in the RULM. The HFMSE ranges from 0 to 66 points, with higher scores indicating a greater degree of function.
Screen failures in Cohort 1 were primarily due to a HFMSE score that was either too high in ambulatory patients or too low in non-ambulatory patients. There were no statistically significant differences otherwise in the baseline demographics of enrolled patients compared to screen failures.
“The baseline demographics we observed in Cohort 1 are consistent with our expectations for the patient population targeted in this first Phase 2 clinical trial of CK-2127107,” said Fady I. Malik, MD, PhD, Cytokinetics’ Executive Vice President of Research & Development. “Adolescent and adult patients with SMA have previously had limited opportunities to participate in clinical trials and we are pleased to be gaining real-world insights into how to optimize design and inclusion criteria for future trials that may enroll this growing patient population.”
