Andrew Wolff
Analyst · JMP Securities
Thank you, Robert. As Robert mentioned, we progressed the clinical development of our lead skeletal muscle activator drug candidate, CK-357, during the fourth quarter with the completion of Part A of our
Phase II multiple-dose trial, CY 4024, and the presentation of key tolerability data from that study.
Part A of this trial was a randomized double-blind placebo-controlled multiple-dose clinical trial designed to assess the safety, tolerability, pharmacokinetics and pharmacodynamics of 14 days dosing of CK-357 in 24 patients with ALS who were not concurrently receiving riluzole. We conducted this trial to better understand the adverse event of dizziness, which we observed in ALS patients after a single dose of CK-357 in our Phase IIa Evidence of Effect study which we presented in December 2010.
Now, in Part A of CY 4024, we found that CK-357 appeared well tolerated as a single agent after 3 dose levels we evaluated, 125 mg, 250 mg and 375 mg daily. The incidence and persistence of dizziness appeared dose-related, but was mild in severity in all patients who completed the study drug treatment. Most importantly, most reports of dizziness began early after initiation of treatment and resolved spontaneously within the first week. No serious adverse events were reported.
Although the trial lacked the statistical power to detect significant differences in parameters of clinical effectiveness, trends to improve the clinical outcome measures were observed. These improvements were observed especially after the highest dose of 375 mg daily. Four of 5 patients who completed treatment in this dose group reported improvement in their global assessments. And 3 of these 5 patients improved at least 1 point on the revised ALS functional rating scale or ALSFRS-R.
The changes observed in maximum voluntary ventilation after 2 weeks of dosing of 375 mg compared favorably to improvements observed at 24 hours after a single 500 mg dose of CK-357 in the prior Phase IIa Evidence of Effect clinical trial in ALS patients.
In addition to this trial, during the fourth quarter, we initiated 2 Phase II clinical trials in ALS patients, both of which are enrolling well. We initiated Part B of CY 4024, which is designed to assess the safety, tolerability, pharmacokinetics and pharmacodynamics of 14 days dosing of CK-357 in 24 additional patients with ALS who are also currently receiving riluzole 50 mg per day. We expect that the results from Part B along with those gathered in Part A will assist us in further understanding the tolerability profile of CK-357 administered as a fixed dose each day.
Also during the quarter, we initiated a Phase II clinical trial in patients with ALS, CY 4025. CY 4025 is a randomized double-blind placebo-controlled clinical trial in which CK-357 is administered for 21 days in ascending multiple doses of 7 days each using a twice-daily regimen to an estimated 24 patients with ALS taking riluzole 50 mg per day.
Patients are randomized 3-to-1 to receive twice-daily oral doses of CK-357 or placebo. After 7 days of treatment with CK-357 at the starting dose of 125 mg twice daily, the dose is escalated to 125 mg in the morning and 250 mg in the evening. And after 7 days at this dose, to 250 mg twice daily for the final 7 days of dosing. Patients who do not tolerate dose escalation may return to the previous tolerated dose level and remain at that dose level to complete the study. Placebo patients undergo a similar dummy dose titration to maintain the blind.
The primary objective of CY 4025 is to assess the safety and tolerability of CK-357 when administered using a twice-daily dose in regiment to patients with ALS. The secondary objective of this clinical trial are to evaluate the ALSFRS, other measures of preliminary function, muscles strengthen fatigue, physician and patient global assessment and relationships between dose, plasma concentration and functional affects in these patients while receiving 3 weeks treatment with CK-357 as a indicated doses or placebo. Data from this trial together with data from CY-24, Part A & B may help us optimize dosing schemes for CK-357 in ALS patients.
Lastly, we continue to enroll patients in our Phase IIa Evidence of Effect trial of CK-357 and patients with generalized myasthenia gravis. To remind you, this is a double-blind, randomized, placebo-controlled, 3-period crossover, pharmacokinetic and pharmacodynamic study. Up to 36 patients may be enrolled at approximately 15 study centers in the United States.
Patients enrolled in this trial receive single oral doses of placebo and a CK-357 at 250 mg and 500 mg in random order approximately one week apart. This clinical trial and preclinical research on myasthenia gravis is funded by a $2.8 million grant from a National Institute of Neurological Disorders and Stroke. Enrollment in this trial has been slower than initially projected. And Robert will provide an update on the timing of expected results in a moment.
Turning to our cardiac contractility program, Amgen continues to make progress in enrolling and dosing patients in an international randomized double-blind, placebo-controlled, Phase IIb clinical trial of an intravenous omecamtiv mecarbil and patient is hospitalized at acute heart failure known as ATOMIC-AHF which stands for Acute Treatment with Omecamtiv Mecarbil to Increase Contractility in Acute Heart Failure.
The study is comprised of 3 successes ascending dose cohorts, each of which when roll approximately 200 patients randomized, one-to-one to omecamtiv mecarbil versus placebo. The dose of omecamtiv mecarbil and cohort 1 targets at peak plasma concentration of omecamtiv mecarbil of approximately 115 nano grams per ml. Cohort 2 will target a peak concentration of approximately 230 nano grams per ml and cohort 3 will target 310 nano grams per ml.
This trial is now enrolling patients into cohort 1 at over 100 centers in countries throughout the world. An independent data monitoring committee will review the data when each cohort has reached a specified number of treated patients and determine whether it is safe to open the next cohort. As always additional information about all of our phase II trials can be found at www. clinicaltrials.gov.
With that update on clinical development activities in the fourth quarter, I'll turn the call back over to Sharon.