CK-2017357, A NOVEL ACTIVATOR OF F S M , I I F E S OF THE A T … · 2019-04-01 · CK-2017357...
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CK-2017357 (CK-357) is a small molecule activator of fast skeletal muscle which decreases the rate of calcium release from the regulatory troponin complex thereby sensitizing the sarcomere to calcium. In detergent-permeabilized muscle fibers, this effect results in a leftward shift in the force-calcium relation; muscle fibers produce more force at lower calcium concentrations without a change in maximal force. In intact muscle, the calcium sensitization effect of CK-357 results in increased force generation during submaximal contractions. A first time in human clinical trial (CY4011A) established the safety and tolerability of CK-357 administered as single oral doses to healthy male subjects. A subsequent follow-on study (CY4011B) was performed to determine if the shift in the force-frequency relation demonstrated preclinically could be recapitulated in healthy volunteers. Confirmation that the mechanism of action translated into humans would lend support for further study of CK-357 in disease settings. Significant Increases in Placebo Corrected Summed Force Response by Dose Percent Change in Summed Frequency Peak Force by Dose Analysis and Quality Assessment of Data Percent Change in Peak Force by Plasma Concentration Significant Increases in Placebo Corrected Force Response by Plasma Concentration Study Design Pre-clinical Findings 0 10 20 30 40 50 60 10 Hz 30 Hz 40 Hz 50 Hz 60 Hz 70 Hz 80 Hz 100 Hz 200 Hz Stimulation Frequency (Hz) Specific Tension (N/cm 2 ) Baseline CK-2017357 10mg/kg Subject 053, High Quality Transients Subject 056, Low Quality Transients Force Frequency Response Included in Over Read Dataset Force Frequency Response Included in Over Read Dataset 0.5 1.0 1.5 0.25 0.50 0.75 1.00 5 Hz 7.5 Hz 10 Hz 12.5 Hz 15 Hz 17.5 Hz 25 Hz 50 Hz Time (s) Normalized Force 0 20 40 60 0.0 0.5 1.0 5h assessment, score = 1 +/- stdev, n=3 Stimulation Frequency (Hz) Normalized Peak Force 0 20 40 60 0.0 0.5 1.0 5h assessment, score = 4 +/- stdev, n=3 Stimulation Frequency (Hz) Normalized Peak Force 0.5 1.0 1.5 0.25 0.50 0.75 1.00 5 Hz 7.5 Hz 10 Hz 12.5 Hz 15 Hz 17.5 Hz 25 Hz 50 Hz Time (s) Normalized Force -5 0 5 10 15 20 25 -5 0 5 10 15 20 250 mg 500 mg 1000 mg 250 mg 500 mg 1000 mg 250 mg, n=12 500 mg, n=12 1000 mg, n=12 250 mg, n=8 500 mg, n=9 1000 mg, n=10 * * * * * * Assessment Time Point Summed Force Plasma Conc. Summed Force Plasma Conc. Mean Placebo Corrected Percent Change in Peak Force (% Σ F, sum of frequencies) Mean Placebo Corrected Percent Change in Peak Force (% Σ F, sum of frequencies) Average Plasma Concentration (μg/ml) Average Plasma Concentration (μg/ml) 1h 3 h 5 h 7 h 1 h 3 h 5 h 7 h -5 0 5 10 15 20 25 -5 0 5 10 15 20 Assessment Time Point * * * * * * * * * p < 0.05 +/- SEM * p < 0.05 +/- SEM All Data Dataset Over Read Dataset * p < 0.05 +/- SEM All Data Dataset 5 Hz 7.5 Hz 10 Hz 12.5 Hz 15 Hz 17.5 Hz 25 Hz -10 0 10 20 30 Plasma Concentration (μg/ml), number of observations A (0,4], n = 15 B (4,6], n = 30 C (6,8], n = 31 D (8,12], n = 34 E >12, n = 34 Mean Placebo Corrected Increase in Peak Force (% Change, Single Frequency) * * * * * * * * * * Stimulation Frequency * p < 0.05 +/- SEM Over Read Dataset Plasma Concentration (μg/ml), number of observations 5 Hz 7.5 Hz 10 Hz 12.5 Hz 15 Hz 17.5 Hz 25 Hz -10 0 10 20 30 A (0,4], n = 10 B (4,6], n = 22 C (6,8], n = 23 D (8,12], n = 23 E >12, n = 30 Stimulation Frequency Mean Placebo Corrected Increase in Peak Force (% Change, Single Frequency) * * * * * * * * * * * * * * * * * * * ** * INTRODUCTION INTRODUCTION AND STUDY RATIONALE • Randomized, double-blind, placebo-controlled, 4-way crossover study with 12 subjects. • In random order, three single doses (250, 500, and 1000 mg) of CK-357 and placebo administered orally in a liquid suspension formulation with 7 day washout period between dosing. • Pharmacodynamic effect assessed by transcutaneous nerve stimulation (deep peroneal nerve) to evoke mechanical response of the anterior tibialis muscle. • Isometric force measured at multiple stimulation frequencies (5, 7.5, 10, 12.5, 15, 17.5, 25 and 50 Hz). • Each stimulation protocol consisted of three sequences of stimulation trains delivered in mixed order. Trains were 800 ms in duration and separated by approximately 40 s. • A pre-dose stimulation protocol established the baseline response. Force-frequency response was measured at 1, 3, 5, and 7 hours after dosing with commensurate blood draw to measure CK-357 plasma levels. • Key eligibility criteria: – Healthy male subjects between 18-50 years old – BMI of 18.0 to 30.0 kg/m 2 – Able to comply with and tolerate pharmacodynamic testing procedures The primary objective was to determine the change in force-frequency profile and its relation to CK-357 plasma concentration when administered orally to healthy volunteers. • The peak forces (F) from the three trains at each frequency were averaged and normalized by dividing by the 50 Hz response. • For each subject at each time point, the percent change in normalized force from baseline was calculated for each frequency (%F) as well as the difference of summed forces over all frequencies from the summed baseline normalized to the summed baseline (%™ F). • A dataset containing all data from each subject was assembled and referred to as the All Data set. • A second dataset called the Over Read set was assembled by an expert working prior to unblinding of the study using the following quality assessment score: – Dosing periods for an individual with assessment scores averaging > 2 were rejected in their entirety. Each dosing period was required to have baseline assessment scored at 1 or 2. – The Over Read dataset contained data from each subject and 75% of the overall data. • For each dataset, the placebo-corrected percent changes from baseline and p-values were calculated for each treatment period using a repeated measures ANCOVA model that included treatment, sequence, and period as fixed effects, baseline as a covariate, and subject as a random effect. • Both the All Data and Over Read analysis show significant increases in the summed percent change from baseline metric. • Over Read analysis shows a smoother dose-dependent profile and achieves significance at additional time points for intermediate and low CK-357 doses. • Plasma concentrations between the All Data and Over Read groups are nearly identical for each dose at each time point. • Results are calculated by pooling all time points and binning by coincident plasma concentrations. • Both the All Data and Over Read analysis show significant increases in the percent change from baseline at low to mid stimulation frequencies at multiple concentration bins. • The Over Read analysis shows a smoother dose-dependent profile with significance established over a wider range of stimulation frequencies and plasma concentrations. (A) Human IIa, IId/x Skinned Muscle Fibers Dennis Claflin (Univ. of Michigan) pCa Force (F/F°) (B) In situ Stimulation of Rat EDL via Peroneal Nerve RESULTS STUDY DESIGN &METHODS STUDY DESIGN &METHODS (CONTD.) RESULTS CONCLUSIONS CONCLUSIONS 1. CK-2017357 significantly increased the mean placebo corrected normalized peak force produced in response to transcutaneous electrical stimulation of the tibialis anterior muscles of healthy volunteers in a dose-, concen- tration-, and frequency-depen- dent manner. 2. Applying quality metrics to remove inconsistent data prior to analysis resulted in a less variable dataset that showed a smoother dose- dependent response and significant changes at lower plasma concentrations. 3. The mechanism of action of CK-2017357 as demonstrated in pre-clinical models can be translated into statistically significant and potentially clinically important increases in skeletal muscle perfor- mance in healthy male volunteers. 4. Further evaluation of CK-2017357 in neuromuscular diseases where neural input is limiting as well as other conditions associated with muscle weakness or fatigue is warranted. CK-2017357, A NOVEL ACTIVATOR OF F AST SKELETAL MUSCLE,INCREASES ISOMETRIC FORCE EVOKED BY ELECTRICAL STIMULATION OF THE ANTERIOR TIBIALIS MUSCLE IN HEALTHY MALE SUBJECTS R Hansen 1 , KG Saikali 1 , W Chou 1 , A Russell 1 , M Chen 1 , V Vijayakumar 1 , R Stoltz 2 , S Baudry 3 , R Enoka 4 , D Morgans 1 , AA Wolff 1 , FI Malik 1 1 Cytokinetics, Inc., South San Francisco, CA, United States; 2 Covance, Evansville, IN, United States; 3 Université Libre de Bruxelles, Brussels, Belgium; 4 University of Colorado, Boulder, CO, United States Ideal, i.e. continuous with canonical force frequency shape Continuous but some spread in replicates, minor non-ideality in force frequency shape 2 4 5 Failure, i.e. measurement could not be completed or data could not be fit to extract force parameters Highly discontinuous and underlying traces far from canonical Assessment Score Description Score Value Discontinuous, non-ideal force frequency shape 3 1 Example Force Transients from Stimulation of the Anterior Tibialis in Human Subjects The fast skeletal activator CK-357: (A) increases Ca 2+ -sensitivity of isolated, human type IIa, IIx/d muscle fibers. (B) increases force in rat EDL muscle in situ at sub-tetanic stimulation frequencies. CK-2017357 Sensitizes the Fast Skeletal Sarcomere to Calcium Phamacodynamic Effect Assessed by Transcutaneous Stimulation of the Deep Peroneal Nerve to Evoke a Mechanical Response from the Anterior Tibialis Muscle
Transcript of CK-2017357, A NOVEL ACTIVATOR OF F S M , I I F E S OF THE A T … · 2019-04-01 · CK-2017357...
CK-2017357 (CK-357) is a small molecule activator of fast skeletal muscle which decreases the rate ofcalcium release from the regulatory troponin complex thereby sensitizing the sarcomere to calcium.In detergent-permeabilized muscle fibers, this effect results in a leftward shift in the force-calciumrelation; muscle fibers produce more force at lower calcium concentrations without a change inmaximal force. In intact muscle, the calcium sensitization effect of CK-357 results in increased forcegeneration during submaximal contractions.
A first time in human clinical trial (CY4011A) established the safety and tolerability of CK-357administered as single oral doses to healthy male subjects. A subsequent follow-on study (CY4011B)was performed to determine if the shift in the force-frequency relation demonstrated preclinicallycould be recapitulated in healthy volunteers. Confirmation that the mechanism of action translatedinto humans would lend support for further study of CK-357 in disease settings.
Significant Increases in Placebo Corrected Summed Force Response by Dose
Percent Change in Summed Frequency Peak Force by Dose
Analysis and Quality Assessment of Data
Percent Change in Peak Force by Plasma Concentration
Significant Increases in Placebo Corrected Force Response by Plasma Concentration
Study Design
Pre-clinical Findings
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Assessment Score DescriptionScoreValue
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Subject 053, High Quality Transients
All Data Dataset Over Read Dataset
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Force Frequency Response Includedin Over Read Dataset
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Highly discontinuous and underlying traces far from canonical
Assessment Score DescriptionScoreValue
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* p < 0.05+/- SEM
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Subject 053, High Quality Transients
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Force Frequency Response Includedin Over Read Dataset
Force Frequency Response Includedin Over Read Dataset
Summed Force Plasma Conc. Summed Force Plasma Conc.
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A (0,4], n = 15B (4,6], n = 30C (6,8], n = 31D (8,12], n = 34E >12, n = 34
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Highly discontinuous and underlying traces far from canonical
Discontinuous, non-ideal force frequency shape3
* p < 0.05+/- SEM
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All Data Dataset Over Read Dataset
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20250 mg500 mg1000 mg
250 mg500 mg1000 mg
250 mg, n=12500 mg, n=121000 mg, n=12
250 mg, n=8500 mg, n=91000 mg, n=10
* p < 0.05+/- SEM
* p < 0.05+/- SEM
**
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Assessment Time Point
Subject 053, High Quality Transients
All Data Dataset Over Read Dataset
Subject 056, Low Quality Transients
Force Frequency Response Includedin Over Read Dataset
Force Frequency Response Includedin Over Read Dataset
Summed Force Plasma Conc. Summed Force Plasma Conc.
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oCo
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A (0,4], n = 15B (4,6], n = 30C (6,8], n = 31D (8,12], n = 34E >12, n = 34
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uenc
y)
*
*
*
* *
*
**
*
* *
**
*
* **
*** *
*
Ideal, i.e. continuous with canonical force frequency shape
Continuous but some spread in replicates, minor non-ideality in force frequency shape2
4
5 Failure, i.e. measurement could not be completed or data could not be fit to extract force parameters
Highly discontinuous and underlying traces far from canonical
Assessment Score DescriptionScoreValue
Discontinuous, non-ideal force frequency shape3
1
* p < 0.05+/- SEM
* p < 0.05+/- SEM
All Data Dataset Over Read Dataset
INTRODUCTIONINTRODUCTION AND STUDY RATIONALE
• Randomized, double-blind, placebo-controlled, 4-way crossover study with 12 subjects.
• In random order, three single doses (250, 500, and 1000 mg) of CK-357 and placebo administeredorally in a liquid suspension formulation with 7 day washout period between dosing.
• Pharmacodynamic effect assessed by transcutaneous nerve stimulation (deep peroneal nerve) toevoke mechanical response of the anterior tibialis muscle.
• Isometric force measured at multiple stimulation frequencies (5, 7.5, 10, 12.5, 15, 17.5, 25 and 50 Hz).
• Each stimulation protocol consisted of three sequences of stimulation trains delivered in mixedorder. Trains were 800 ms in duration and separated by approximately 40 s.
• A pre-dose stimulation protocol established the baseline response. Force-frequency response wasmeasured at 1, 3, 5, and 7 hours after dosing with commensurate blood draw to measure CK-357plasma levels.
• Key eligibility criteria:
– Healthy male subjects between 18-50 years old
– BMI of 18.0 to 30.0 kg/m2
– Able to comply with and tolerate pharmacodynamic testing procedures
The primary objective was to determine the change in force-frequency profile and its relation to CK-357 plasma concentration when administered orally to healthy volunteers.
• The peak forces (F) from the three trains at each frequency were averaged and normalized by dividingby the 50 Hz response.
• For each subject at each time point, the percent change in normalized force from baseline wascalculated for each frequency (%F) as well as the difference of summed forces over all frequencies fromthe summed baseline normalized to the summed baseline (%™F).
• A dataset containing all data from each subject was assembled and referred to as the All Data set.
• A second dataset called the Over Read set was assembled by an expert working prior to unblinding ofthe study using the following quality assessment score:
– Dosing periods for an individual with assessment scores averaging > 2 were rejected in their entirety.Each dosing period was required to have baseline assessment scored at 1 or 2.
– The Over Read dataset contained data from each subject and 75% of the overall data.
• For each dataset, the placebo-corrected percent changes from baseline and p-values were calculated foreach treatment period using a repeated measures ANCOVA model that included treatment, sequence,and period as fixed effects, baseline as a covariate, and subject as a random effect.
• Both the All Data and Over Read analysis show significant increases in the summed percent changefrom baseline metric.
• Over Read analysis shows a smoother dose-dependent profile and achieves significance atadditional time points for intermediate and low CK-357 doses.
• Plasma concentrations between the All Data and Over Read groups are nearly identical for eachdose at each time point.
• Results are calculated by pooling all time points and binning by coincident plasma concentrations.
• Both the All Data and Over Read analysis show significant increases in the percent change frombaseline at low to mid stimulation frequencies at multiple concentration bins.
• The Over Read analysis shows a smoother dose-dependent profile with significance establishedover a wider range of stimulation frequencies and plasma concentrations.
(A) Human IIa, IId/x Skinned Muscle Fibers
Dennis Claflin (Univ. of Michigan)
pCa
Forc
e(F
/F°)
(B) In situ Stimulation of Rat EDL via Peroneal Nerve
RESULTSSTUDY DESIGN & METHODS
STUDY DESIGN & METHODS (CONTD.) RESULTS
CONCLUSIONSCONCLUSIONS
1. CK -2 0 1 7 3 5 7 s ign i f i c an t l yincreased the mean placebocorrected normalized peakforce produced in responseto transcutaneous electricalstimulation of the tibialisanterior muscles of healthyvolunteers in a dose-, concen-tration-, and frequency-depen-dent manner.
2. Applying quality metrics toremove incons is tent dataprior to analysis resulted in aless variable dataset thatshowed a smoother dose-d e p e n d e n t re s p o n s e a n dsignificant changes at lowerplasma concentrations.
3. The mechanism of action ofCK-2017357 as demonstratedin pre-clinical models can betranslated into statisticallysignificant and potentiallyclinically important increasesin skeletal muscle perfor-m a n c e i n h e a l t h y m a l evolunteers.
4. F u r t h e r e v a l u a t i o n o fCK-2017357 in neuromusculardiseases where neural inputis limiting as well as otherconditions associated withmuscle weakness or fatigueis warranted.
CK-2017357, A NOVEL ACTIVATOR OF FAST SKELETAL MUSCLE, INCREASES ISOMETRIC FORCE EVOKED BY ELECTRICAL STIMULATION
OF THE ANTERIOR TIBIALIS MUSCLE IN HEALTHY MALE SUBJECTSR Hansen1, KG Saikali1, W Chou1, A Russell1, M Chen1, V Vijayakumar1, R Stoltz2, S Baudry3, R Enoka4, D Morgans1, AA Wolff1, FI Malik1
1Cytokinetics, Inc., South San Francisco, CA, United States; 2Covance, Evansville, IN, United States; 3Université Libre de Bruxelles, Brussels, Belgium; 4University of Colorado, Boulder, CO, United States
0
10
20
30
40
50
60
10 Hz 30 Hz 40 Hz 50 Hz 60 Hz 70 Hz 80 Hz 100 Hz 200 Hz
Stimulation Frequency (Hz)
Spec
ific
Tens
ion
(N/c
m2)
Baseline
CK-2017357 10mg/kg
-5
0
5
10
15
20
25
-5
0
5
10
15
20250 mg500 mg1000 mg
250 mg500 mg1000 mg
250 mg, n=12500 mg, n=121000 mg, n=12
250 mg, n=8500 mg, n=91000 mg, n=10
**
* *
* *
Assessment Time Point
Subject 053, High Quality Transients Subject 056, Low Quality Transients
Summed Force Plasma Conc. Summed Force Plasma Conc.
Mea
nPl
aceb
oCo
rrec
ted
Perc
ent
Chan
gein
Peak
Forc
e(%Σ
F,su
mof
freq
uenc
ies)
Mea
nPl
aceb
oCo
rrec
ted
Perc
ent
Chan
gein
Peak
Forc
e(%Σ
F,su
mof
freq
uenc
ies)A
veragePlasm
aConcentration
(µg/ml)
Average
Plasma
Concentration(µg/m
l)1 h 3 h 5 h 7 h 1 h 3 h 5 h 7 h
-5
0
5
10
15
20
25
-5
0
5
10
15
20
Assessment Time Point
* **
**
*
**
0.50
0.75
1.00 5 Hz7.5 Hz10 Hz12.5 Hz15 Hz17.5 Hz25 Hz50 Hz
orm
aliz
edFo
rce
0.50
0.75
1.00 5 Hz7.5 Hz10 Hz12.5 Hz15 Hz17.5 Hz25 Hz50 Hz
Nor
mal
ized
Forc
e
Ideal, i.e. continuous with canonical force frequency shape
Continuous but some spread in replicates, minor non-ideality in force frequency shape2
4
5 Failure, i.e. measurement could not be completed or data could not be fit to extract force parameters
Highly discontinuous and underlying traces far from canonical
Assessment Score DescriptionScoreValue
Discontinuous, non-ideal force frequency shape3
1
* p < 0.05+/- SEM
* p < 0.05+/- SEM
All Data Dataset Over Read Dataset
Example Force Transients from Stimulation of the Anterior Tibialis in Human Subjects
The fast skeletal activator CK-357:
(A) increases Ca2+-sensitivity of isolated, human type IIa, IIx/d muscle fibers.
(B) increases force in rat EDL muscle in situ at sub-tetanic stimulation frequencies.
CK-2017357 Sensitizes the Fast Skeletal Sarcomere to Calcium
Phamacodynamic Effect Assessed by Transcutaneous Stimulation of the Deep Peroneal Nerve to Evoke a Mechanical Response from the Anterior Tibialis Muscle
