Drug-induced QT Prolongation, Pharmacokinetics, Pharmacodynamics
Conditions
Brief summary
This study will assess whether exposure response analysis of the electrocardiographic QTc and J-Tpeakc intervals in Phase 1 clinical pharmacology studies can be used to confirm that drugs that predominantly block the potassium channel encoded by the human ether-à-go-go-related gene (hERG) with approximately equipotent late sodium and/or calcium block (balanced ion channel drugs) do not cause J-Tpeakc prolongation and that drugs that predominantly block hERG without late sodium or L-type calcium current block (predominant hERG drugs) cause QTc prolongation.
Detailed description
This study will assess whether exposure response analysis of the electrocardiographic QTc and J-Tpeakc intervals in Phase 1 clinical pharmacology studies can be used to confirm that balanced ion channel drugs do not cause J-Tpeakc prolongation and that predominant hERG drugs cause QTc prolongation. This clinical study consists of 2 parts: a 50-subject parallel part (Part 1) and a 10-subject crossover part (Part 2). Up to 74 healthy subjects will be enrolled (including 14 potential replacement subjects). Part 1 will be a double-blind, randomized, placebo-controlled, 1 period parallel design to assess the effect of 4 marketed drugs and 1 placebo on the QTc and J-Tpeakc intervals in 50 healthy subjects. A parallel design similar to a single or multiple ascending dose (SAD/MAD) Phase 1 study will be used that will result in each study drug being administered to 10 subjects, and placebo to 10 subjects, in 1 period of 3 consecutive days to achieve low and high drug exposure. Part 2 will be a double-blind, randomized, 2-period crossover design to assess the effect of hERG block (dofetilide) versus calcium block (diltiazem) on the QTc and J-Tpeakc intervals in 10 healthy subjects on Days 1, 2, and 3 (Period 1) and Days 8, 9, and 10 (Period 2).
Interventions
DRUGRanolazine
Ranolazine 1500 mg orally two times per day for 2.5 days
DRUGVerapamil
Verapamil 120 mg immediate release (IR) morning and afternoon doses on Days 1 and 2, 240 mg extended release (ER) evening dose on Days 1 and 2, and 120 mg IR morning dose on Day 3 (all oral doses)
Lopinavir / Ritonavir 800 mg / 200 mg orally two times per day for 2.5 days
DRUGChloroquine
Chloroquine 1000 mg on Day 1, 500 mg on Day 2, 1000 mg on Day 3 (all oral doses)
DRUGPlacebo
Placebo (administered orally)
DRUGDofetilide and Diltiazem
In one period subjects receive Dofetilide 0.125 mg on Day 1, 0.375 mg on Day 3. In a second period (randomized cross-over) subject receive Diltiazem 120 mg IR morning dose on Day 8, 240 mg ER evening dose on Days 8 and 9, and 120 mg IR on Day 10 with coadministration of 0.25 mg dofetilide on Day 10.
Sponsors
Spaulding Clinical Research LLC
Food and Drug Administration (FDA)
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Intervention model description
This clinical study consists of 2 parts: * 50 subjects in Part 1 will be randomized to receive one of four drugs (ranolazine, verapamil, lopinavir / ritonavir, chloroquine) or placebo over 3 days. * 10 subjects in Part 2 will be randomized to receive one of two treatment sequences (1. dofetilide or 2. diltiazem combined with dofetilide) over 3 days, then after washout, the subjects will receive the other treatment sequence over 3 days. Thus, Part 2 will have a cross-over component. A maximum of 14 additional replacement subjects may be enrolled.
Eligibility
Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
1. Subject signs an institutional review board (IRB) approved written informed consent and privacy language as per national regulations (e.g., Health Insurance Portability and Accountability Act \[HIPAA\] authorization) before any study related procedures are performed. 2. Subject is a healthy man or woman, 18 to 50 years of age, inclusive, who weighs at least 50 kg (110 pounds) and has a body mass index of 18 to 30 kg/m2, inclusive, at Screening. 3. Subject has normal medical history findings, clinical laboratory results, vital sign measurements, 12 lead ECG results, and physical examination findings at Screening or, if abnormal, the abnormality is not considered clinically significant (as determined and documented by the investigator or designee). 4. Female subjects will be at least 2 years postmenopausal, surgically sterile, or practicing 2 highly effective methods of birth control (as determined by the investigator or designee; one of the methods must be a barrier technique). 5. Female subjects must not be pregnant or lactating before enrollment in the study. 6. Male or female subjects must agree to practice 2 highly effective methods of birth control (as determined by the investigator or designee; one of the methods must be a barrier technique) from Screening until 30 days after the last dose of study drug. 7. Subject is highly likely (as determined by the investigator) to comply with the protocol defined procedures and to complete the study.
Exclusion criteria
1. Subject has a safety 12 lead ECG result at Screening or Check in with evidence of any of the following abnormalities: * QTc using Fridericia correction (QTcF) \>430 msec * PR interval \>220 msec or \<120 msec * QRS duration \>110 msec * Second- or third-degree atrioventricular block * Complete left or right bundle branch block or incomplete right bundle branch block * Heart rate \<50 or \>90 beats per minute * Pathological Q-waves (defined as Q wave \>40 msec) * Ventricular pre-excitation 2. Subject has more than 12 ectopic beats during the 3 hour Holter ECG at Screening. 3. Subject has a history of unexplained syncope, structural heart disease, long QT syndrome, heart failure, myocardial infarction, angina, unexplained cardiac arrhythmia, torsade de pointes, ventricular tachycardia, or placement of a pacemaker or implantable defibrillator. Subjects will also be excluded if there is a family history of long QT syndrome (genetically proven or suggested by sudden death of a close relative due to cardiac causes at a young age) or Brugada syndrome. 4. Subject has a history or current evidence of any clinically significant (as determined by the investigator) cardiovascular, dermatologic, endocrine, gastrointestinal, hematologic, hepatic, immunologic, metabolic, neurologic, psychiatric, pulmonary, renal, urologic, and/or other major disease or malignancy (excluding nonmelanoma skin cancer). The investigator may allow exceptions to these criteria (e.g., cholecystectomy, childhood asthma) following discussion with the medical monitor. 5. Subject has a history of thoracic surgery. 6. Subject has any condition possibly affecting study drug absorption (e.g., gastrectomy, Crohn's disease, irritable bowel syndrome). 7. Subject has a skin condition likely to compromise ECG electrode placement. 8. Subject is a female with breast implants. 9. Subject's laboratory test results at Screening or Check in are outside the reference ranges provided by the clinical laboratory and considered clinically significant (as determined and documented by the investigator or designee). 10. Subject's laboratory test results at Screening or Check in indicate hypokalemia, hypocalcemia, or hypomagnesemia according to lower limits of the reference ranges provided by the clinical laboratory. 11. Subject's laboratory test results at Screening or Check in are \>2 × the upper limit of normal (ULN) for alanine aminotransferase or aspartate aminotransferase, \>1.5 × ULN for bilirubin, or \>1.5 × ULN for creatinine. 12. Subject has a positive test result at Screening for human immunodeficiency virus I or II antibody, hepatitis C virus antibodies, or hepatitis B surface antigen. 13. Subject has a mean systolic blood pressure \<100 or \>140 mmHg or a mean diastolic blood pressure \<50 or \>90 mmHg at either Screening or Check in. Blood pressure will be measured in triplicate after the subject has been resting in a supine position for a minimum of 5 minutes. 14. Subject has a known hypersensitivity to any of the study drugs or related compounds. 15. Subject has consumed alcohol, xanthine containing products (e.g., tea, coffee, chocolate, cola), caffeine, grapefruit, or grapefruit juice within 48 hours before dosing or anticipates an inability to abstain from these products throughout the duration of the study. 16. Subject has used nicotine containing products (e.g., cigarettes, cigars, chewing tobacco, snuff) within 6 weeks before Screening (self reported). 17. Subject is unable to tolerate a controlled, quiet, study conduct environment, including avoidance of music, television, movies, games, and activities that may cause excitement, emotional tension, or arousal during the prespecified time points (e.g., before and during ECG extraction windows). 18. Subject is unwilling to comply with study rules, including the study-specific diet, attempting to void at specified times (e.g., before ECG extraction windows), remaining quiet, awake, undistracted, motionless, and supine during specified times, and avoiding vigorous exercise as directed. 19. Subject has a history of consuming more than 14 units of alcoholic beverages per week within 6 months before Screening, has a history of alcoholism or drug/chemical/substance abuse within 2 years before Screening (Note: 1 unit = 12 ounces of beer, 4 ounces of wine, or 1 ounce of spirits/hard liquor), or has a positive test result for alcohol or drugs of abuse at Screening or Check in. 20. Subject has used any prescription or nonprescription drugs (including aspirin or nonsteroidal anti inflammatory drugs \[NSAIDs\] and excluding oral contraceptives and acetaminophen) within 14 days or 5 half lives (whichever is longer), or complementary and alternative medicines within 28 days before the first dose of study drug. 21. Subject is currently participating in another clinical study of an investigational drug or has been treated with any investigational drug within 30 days or 5 half-lives (whichever is longer) of the compound. 22. Subject has had any significant blood loss, donated 1 unit (450 mL) of blood or more, or received a transfusion of any blood or blood products within 60 days, or donated plasma within 7 days before Check in. 23. Subject has any other condition that precludes his or her participation in the study (as determined by the investigator). 24. Subject is unwilling to have genetic analysis performed or a blood sample collected for isolating peripheral blood mononuclear cells (PBMCs).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change From Baseline J-Tpeakc With Balanced Ion Channel Drugs (Ranolazine, Verapamil, Lopinavir / Ritonavir) | 3 days | The primary outcome measure for the balanced ion channel drugs (ranolazine, verapamil, lopinavir / ritonavir) is for the upper bound of the 2-sided 90% confidence interval (CI) to be \<10 msec for the projected placebo-corrected change from baseline J-Tpeakc effect at the peak plasma level on Day 3 using a linear mixed-effects exposure response model. Placebo drug concentration was set to 0 (see SAP). |
| Change From Baseline QTc With Predominant hERG Blocking Drug (Chloroquine) | 3 days | The primary outcome measure for the predominant hERG drug (chloroquine) is for the upper bound of the 2-sided 90% CI to be ≥10 msec for the projected placebo-corrected change from baseline QTc effect at the peak plasma level on Day 1 using a linear mixed-effects exposure response model |
| QTc Shortening From Calcium Block (Diltiazem) in the Presence of hERG Block (Dofetilide) | 3 days | * It will be assessed whether the projected QTc effect of dofetilide alone is significantly greater (i.e., p\<0.05) than the projected QTc effect of the combination of dofetilide + diltiazem. This will be assessed at the dofetilide peak plasma level on Day 3 (computed from the combination of dofetilide + diltiazem) on the pooled dofetilide alone, diltiazem alone, and dofetilide + diltiazem data using a linear mixed effects model. * Subsequently, and if the test is significant for QTc, the same test will be performed to assess calcium block (diltiazem) effects on J-Tpeakc. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Ranolazine Ranolazine 1500 mg two times per day for 2.5 days
Ranolazine: Ranolazine 1500 mg orally two times per day for 2.5 days | 10 |
| Verapamil Verapamil 120 mg immediate release (IR) morning and afternoon doses on Days 1 and 2, 240 mg extended release (ER) evening dose on Days 1 and 2, and 120 mg IR morning dose on Day 3
Verapamil: Verapamil 120 mg immediate release (IR) morning and afternoon doses on Days 1 and 2, 240 mg extended release (ER) evening dose on Days 1 and 2, and 120 mg IR morning dose on Day 3 (all oral doses) | 10 |
| Lopinavir / Ritonavir Lopinavir / Ritonavir 800 mg / 200 mg two times per day for 2.5 days
Lopinavir / Ritonavir: Lopinavir / Ritonavir 800 mg / 200 mg orally two times per day for 2.5 days | 10 |
| Chloroquine Chloroquine 1000 mg on Day 1, 500 mg on Day 2, 1000 mg on Day 3
Chloroquine: Chloroquine 1000 mg on Day 1, 500 mg on Day 2, 1000 mg on Day 3 (all oral doses) | 10 |
| Placebo Placebo capsules
Placebo: Placebo (administered orally) | 10 |
| Dofetilide and Diltiazem In one period subjects receive Dofetilide 0.125 mg on Day 1, 0.375 mg on Day 3.
In a second period (randomized cross-over) subject receive Diltiazem 120 mg IR morning dose on Day 8, 240 mg ER evening dose on Days 8 and 9, and 120 mg IR on Day 10 with coadministration of 0.25 mg dofetilide on Day 10.
Dofetilide and Diltiazem: In one period subjects receive Dofetilide 0.125 mg on Day 1, 0.375 mg on Day 3.
In a second period (randomized cross-over) subject receive Diltiazem 120 mg IR morning dose on Day 8, 240 mg ER evening dose on Days 8 and 9, and 120 mg IR on Day 10 with coadministration of 0.25 mg dofetilide on Day 10. | 10 |
| Total | 60 |
Baseline characteristics
| Characteristic | Total | Ranolazine | Verapamil | Lopinavir / Ritonavir | Chloroquine | Placebo | Dofetilide and Diltiazem |
|---|---|---|---|---|---|---|---|
| Age, Continuous | 31.7 years STANDARD_DEVIATION 8.7 | 33.8 years STANDARD_DEVIATION 8 | 28.2 years STANDARD_DEVIATION 7.9 | 32.6 years STANDARD_DEVIATION 11.1 | 28.8 years STANDARD_DEVIATION 8.8 | 33.3 years STANDARD_DEVIATION 9 | 33.4 years STANDARD_DEVIATION 7.2 |
| Diastolic Blood Pressure | 65.9 mmHg STANDARD_DEVIATION 7.5 | 66.7 mmHg STANDARD_DEVIATION 8.7 | 63.4 mmHg STANDARD_DEVIATION 6.9 | 67.3 mmHg STANDARD_DEVIATION 8.5 | 66.9 mmHg STANDARD_DEVIATION 5.5 | 66.7 mmHg STANDARD_DEVIATION 9 | 64.2 mmHg STANDARD_DEVIATION 6.9 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 4 Participants | 0 Participants | 0 Participants | 0 Participants | 1 Participants | 2 Participants | 1 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 55 Participants | 10 Participants | 9 Participants | 10 Participants | 9 Participants | 8 Participants | 9 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 1 Participants | 0 Participants | 1 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Heart Rate | 60.7 BPM STANDARD_DEVIATION 8.2 | 59.8 BPM STANDARD_DEVIATION 8.9 | 63.6 BPM STANDARD_DEVIATION 9.8 | 61.3 BPM STANDARD_DEVIATION 9.3 | 59.2 BPM STANDARD_DEVIATION 9.5 | 58.6 BPM STANDARD_DEVIATION 5.6 | 61.9 BPM STANDARD_DEVIATION 6.1 |
| J-Tpeakc (heart rate corrected J-Tpeak interval) | 234.3 ms STANDARD_DEVIATION 22.3 | 227.7 ms STANDARD_DEVIATION 22.7 | 239.4 ms STANDARD_DEVIATION 22.4 | 231.0 ms STANDARD_DEVIATION 14.5 | 238.7 ms STANDARD_DEVIATION 20.3 | 229.5 ms STANDARD_DEVIATION 24.2 | 239.7 ms STANDARD_DEVIATION 29.4 |
| PR Interval | 169.7 ms STANDARD_DEVIATION 19.2 | 182.4 ms STANDARD_DEVIATION 23.9 | 178.4 ms STANDARD_DEVIATION 16.2 | 162.3 ms STANDARD_DEVIATION 16.5 | 159.1 ms STANDARD_DEVIATION 15.5 | 164.4 ms STANDARD_DEVIATION 15 | 171.6 ms STANDARD_DEVIATION 19.4 |
| QRS Duration | 86.3 ms STANDARD_DEVIATION 8.4 | 90.1 ms STANDARD_DEVIATION 7.7 | 82.9 ms STANDARD_DEVIATION 8.2 | 87.1 ms STANDARD_DEVIATION 5.8 | 84.7 ms STANDARD_DEVIATION 6.7 | 85.4 ms STANDARD_DEVIATION 11.5 | 87.3 ms STANDARD_DEVIATION 9.4 |
| QTc (Fridericia's heart rate corrected QT interval) | 389.0 ms STANDARD_DEVIATION 19.2 | 386.0 ms STANDARD_DEVIATION 20.2 | 386.5 ms STANDARD_DEVIATION 17.8 | 383.9 ms STANDARD_DEVIATION 17.1 | 393.3 ms STANDARD_DEVIATION 20 | 387.1 ms STANDARD_DEVIATION 13.7 | 397.1 ms STANDARD_DEVIATION 26.1 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 4 Participants | 1 Participants | 1 Participants | 0 Participants | 1 Participants | 1 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 32 Participants | 6 Participants | 5 Participants | 5 Participants | 7 Participants | 5 Participants | 4 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 24 Participants | 3 Participants | 4 Participants | 5 Participants | 2 Participants | 4 Participants | 6 Participants |
| Region of Enrollment United States | 60 Participants | 10 Participants | 10 Participants | 10 Participants | 10 Participants | 10 Participants | 10 Participants |
| Sex: Female, Male Female | 22 Participants | 2 Participants | 4 Participants | 6 Participants | 3 Participants | 2 Participants | 5 Participants |
| Sex: Female, Male Male | 38 Participants | 8 Participants | 6 Participants | 4 Participants | 7 Participants | 8 Participants | 5 Participants |
| Systolic Blood Pressure | 115.0 mmHg STANDARD_DEVIATION 8.5 | 116.6 mmHg STANDARD_DEVIATION 9.5 | 109.2 mmHg STANDARD_DEVIATION 6.6 | 119.4 mmHg STANDARD_DEVIATION 10 | 114.8 mmHg STANDARD_DEVIATION 8.1 | 116.6 mmHg STANDARD_DEVIATION 6.4 | 113.4 mmHg STANDARD_DEVIATION 8.2 |
| Tpeak-Tend interval | 68.7 ms STANDARD_DEVIATION 9.2 | 68.7 ms STANDARD_DEVIATION 7.9 | 65.1 ms STANDARD_DEVIATION 6.6 | 65.7 ms STANDARD_DEVIATION 7.9 | 69.7 ms STANDARD_DEVIATION 8.7 | 72.5 ms STANDARD_DEVIATION 6.4 | 70.6 ms STANDARD_DEVIATION 14.8 |
| Weight | 75.5 Kg STANDARD_DEVIATION 11.1 | 80.3 Kg STANDARD_DEVIATION 11.1 | 77.1 Kg STANDARD_DEVIATION 10.2 | 76.2 Kg STANDARD_DEVIATION 6.1 | 72.4 Kg STANDARD_DEVIATION 11.3 | 77.5 Kg STANDARD_DEVIATION 15.6 | 69.5 Kg STANDARD_DEVIATION 9.4 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk | EG004 affected / at risk | EG005 affected / at risk |
|---|---|---|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 10 | 0 / 10 | 0 / 10 | 0 / 10 | 0 / 10 | 0 / 10 |
| other Total, other adverse events | 3 / 10 | 5 / 10 | 9 / 10 | 4 / 10 | 2 / 10 | 8 / 10 |
| serious Total, serious adverse events | 0 / 10 | 0 / 10 | 0 / 10 | 0 / 10 | 0 / 10 | 0 / 10 |
Outcome results
Primary
Change From Baseline J-Tpeakc With Balanced Ion Channel Drugs (Ranolazine, Verapamil, Lopinavir / Ritonavir)
The primary outcome measure for the balanced ion channel drugs (ranolazine, verapamil, lopinavir / ritonavir) is for the upper bound of the 2-sided 90% confidence interval (CI) to be \<10 msec for the projected placebo-corrected change from baseline J-Tpeakc effect at the peak plasma level on Day 3 using a linear mixed-effects exposure response model. Placebo drug concentration was set to 0 (see SAP).
Time frame: 3 days
Population: Placebo data was used in the statistical analysis to account for placebo effect. Chloroquine, and dofetilide and diltiazem data were collected but not part of the primary J-Tpeakc analysis. The underlying raw data (available at https://doi.org/10.13026/C2967M) were the input in the statistical analysis. Summary included per PRS review team request.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Ranolazine | Change From Baseline J-Tpeakc With Balanced Ion Channel Drugs (Ranolazine, Verapamil, Lopinavir / Ritonavir) | -8.3 ms |
| Verapamil | Change From Baseline J-Tpeakc With Balanced Ion Channel Drugs (Ranolazine, Verapamil, Lopinavir / Ritonavir) | -7.8 ms |
| Lopinavir / Ritonavir | Change From Baseline J-Tpeakc With Balanced Ion Channel Drugs (Ranolazine, Verapamil, Lopinavir / Ritonavir) | -11.5 ms |
| Placebo | Change From Baseline J-Tpeakc With Balanced Ion Channel Drugs (Ranolazine, Verapamil, Lopinavir / Ritonavir) | -10.9 ms |
Comparison: Upper bound of the 2-sided 90% confidence interval (CI) to be \<10 msec for the projected placebo-corrected change from baseline J-Tpeakc effect at the peak plasma level on Day 3 using a linear mixed-effects exposure response model90% CI: [-9.5, 12]Mixed Models Analysis
Comparison: Upper bound of the 2-sided 90% confidence interval (CI) to be \<10 msec for the projected placebo-corrected change from baseline J-Tpeakc effect at the peak plasma level on Day 3 using a linear mixed-effects exposure response model90% CI: [-11.4, 6.1]Mixed Models Analysis
Comparison: Upper bound of the 2-sided 90% confidence interval (CI) to be \<10 msec for the projected placebo-corrected change from baseline J-Tpeakc effect at the peak plasma level on Day 3 using a linear mixed-effects exposure response model90% CI: [-14.6, 8.8]Mixed Models Analysis
Primary
Change From Baseline QTc With Predominant hERG Blocking Drug (Chloroquine)
The primary outcome measure for the predominant hERG drug (chloroquine) is for the upper bound of the 2-sided 90% CI to be ≥10 msec for the projected placebo-corrected change from baseline QTc effect at the peak plasma level on Day 1 using a linear mixed-effects exposure response model
Time frame: 3 days
Population: Ranolazine, verapamil, lopinavir/ritonavir, and dofetilide and diltiazem data were collected but not part of the primary QTc analysis. The underlying raw data (available at https://doi.org/10.13026/C2967M) were the input in the statistical analysis. Median and range summary included per PRS review team request.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Chloroquine | Change From Baseline QTc With Predominant hERG Blocking Drug (Chloroquine) | 17.7 ms |
| Placebo | Change From Baseline QTc With Predominant hERG Blocking Drug (Chloroquine) | -9.3 ms |
Comparison: Upper bound of the 2-sided 90% CI to be ≥10 msec for the projected placebo-corrected change from baseline QTc effect at the peak plasma level on Day 1 using a linear mixed-effects exposure response model.90% CI: [22.6, 38.9]Mixed Models Analysis
Primary
QTc Shortening From Calcium Block (Diltiazem) in the Presence of hERG Block (Dofetilide)
* It will be assessed whether the projected QTc effect of dofetilide alone is significantly greater (i.e., p\<0.05) than the projected QTc effect of the combination of dofetilide + diltiazem. This will be assessed at the dofetilide peak plasma level on Day 3 (computed from the combination of dofetilide + diltiazem) on the pooled dofetilide alone, diltiazem alone, and dofetilide + diltiazem data using a linear mixed effects model. * Subsequently, and if the test is significant for QTc, the same test will be performed to assess calcium block (diltiazem) effects on J-Tpeakc.
Time frame: 3 days
Population: QTc, J-Tpeakc, and drug concentration data from all subjects in the dofetilide and diltiazem arm. Ranolazine, verapamil, lopinavir/ritonavir, chloroquine, and placebo data were collected but not part of this analysis (see SAP). The underlying raw data were the input in the statistical analysis. Summary included per PRS review team request.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Dofetilide and Diltiazem | QTc Shortening From Calcium Block (Diltiazem) in the Presence of hERG Block (Dofetilide) | 2.2 ms |
| Diltiazem+Dofetilide | QTc Shortening From Calcium Block (Diltiazem) in the Presence of hERG Block (Dofetilide) | -1.7 ms |