WO1999056134A1 - A method for monitoring the tolerability of levosimendan administration - Google Patents

A method for monitoring the tolerability of levosimendan administration Download PDF

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Publication number
WO1999056134A1
WO1999056134A1 PCT/FI1999/000330 FI9900330W WO9956134A1 WO 1999056134 A1 WO1999056134 A1 WO 1999056134A1 FI 9900330 W FI9900330 W FI 9900330W WO 9956134 A1 WO9956134 A1 WO 9956134A1
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levosimendan
administration
metabolite
monitoring
tolerability
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PCT/FI1999/000330
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French (fr)
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Lasse Lehtonen
Timo Lotta
Pekka Ottoila
Aira HEIKKILÄ
Hanna Nikkanen
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Orion Corporation
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Priority to AU35247/99A priority Critical patent/AU3524799A/en
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
    • G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
    • G01N33/94—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving narcotics or drugs or pharmaceuticals, neurotransmitters or associated receptors
    • G01N33/9453—Cardioregulators, e.g. antihypotensives, antiarrhythmics

Definitions

  • the present invention relates to a method for monitoring and/or assessing the tolerability of levosimendan administration, particularly oral administration, in patients.
  • Levosimendan or (-)-[[4-(l,4,5,6-tetrahydro-4-methyl-6-oxo-3-pyridazinyl)phenyl]- hydrazono]propanedinitrile, is useful in the treatment of congestive heart failure.
  • Levosimendan which is the (-)-enantiomer of [[4-(l,4,5,6-tetrahydro-4-methyl- 6-oxo-3-pyridazinyl)phenyl]hydrazono]propanedinitrile, and the method for its preparation is described in EP 565546 Bl.
  • Levosimendan is potent in the treatment of heart failure and has significant calcium dependent binding to troponin.
  • Levosimendan is represented by the formula:
  • levosimendan Oral administration of levosimendan has proved to be difficult.
  • the elimination half-life of levosimendan in human is short, about 1 h. Therefore, using conventional immediate release oral formulations levosimendan should be administered frequently during the day.
  • the gastrointestinal absorption of levosimendan is also rapid. Therefore, using immediate release oral formulations high peak plasma concentrations of levosimendan are reached rapidly and abruptly, typically within 1 hour. High plasma concentrations of levosimendan tend to increase heart rate which is an undesired effect in heart failure patients.
  • compositions which release drug over an extended period of time provide many advantages over conventional rapid release compositions. Such advantages include smaller variation of drug concentrations in plasma and, as a result, steady therapeutic response, reduced frequency of administration and reduction of side effects.
  • levosimendan is susceptible to metabolization in the lower gastrointestinal tract, in particular in the large intestine, by the intestinal bacteria.
  • Such metabolic route results ultimately in the formation of an active first-pass metabolite, (R)-N-[4-(l,4,5,6-tetrahydro-4-methyl-6-oxo-3-pyridazinyl)phenyl]acetamide (LI) whose elimination half-life is substantially longer than that of levosimendan.
  • the accumulation of the active metabolite has been found to be the cause of the tolerability problems associated with the oral administration of the extended release preparations of levosimendan.
  • the discovery of the active metabolite and its formation route makes it now possible to use this metabolite as a tool in monitoring and/or assessing the tolerability of levosimendan administration in patients.
  • Fig 1 shows a calibration sample for the active metabolite (H) from a volunteer as determined by liquid chromatography-tandem mass spectrometry.
  • Fig. 2 shows a post-dose plasma sample for the active metabolite (LI) from a volunteer as determined by liquid chromatography-tandem mass spectrometry.
  • Fig. 3 shows the correlation of heart rate change to the plasma level (ng/ml) of metabolite (LI) in heart failure patients.
  • the present invention provides a method for monitoring and/or assessing the tolerability of levosimendan administration, particularly oral administration, in a patient which method comprises determining the plasma level of metabolite (TT) of a patient after levosimendan administration.
  • TT plasma level of metabolite
  • the plasma level of metabolite (TT) correlates well with the occurrence of undesired effects such as severe headache, increased heart rate and palpitation.
  • the steady-state plasma level of metabolite (LJ) should be less than 20 ng/ml, preferably less than 10 ng/ml.
  • the plasma level of metabolite (LI) is preferably determined at least 48 hours after levosimendan administration.
  • the plasma level of metabolite (LJ) is determined in a steady- state situation.
  • the method of monitoring and/or assessing the tolerability of levosimendan administration is particularly important when controlled/extended release formulations of levosimendan are administered.
  • Levosimendan may be administered monthly, weekly or daily or several times a day depending upon the patient's needs.
  • the daily dosage of levosimendan in man in oral administration is from about 0.1 to 20 mg, typically from about 0.5 to 10 mg, more typically from about 1 to 4 mg, in one daily dose or divided into several doses per day. The dosage depends e.g. on the age, body weight and condition of the patient.
  • levosimendan is administered daily 1 - 3 times a day.
  • the plasma level of metabolite (TT) is determined at least 48 hours after levosimendan administration and, preferably, after the steady-state plasma level of (LI) has been reached.
  • the steady-state plasma level of (TT) has been reached in about 7 - 14 days from the first dose.
  • the plasma levels of metabolite (Ti) may vary considerably between patients regardless of the levosimendan dose.
  • the plasma level of metabolite (LT) is monitored over the whole oral treatment period, e.g. by taking a blood sample from the patient periodically, e.g. daily, weekly, biweekly or monthly.
  • the plasma level of the active metabolite (LI) can be measured according to any method known in the art. An example of a method for determining the plasma level of metabolite (TT) described in detail in Example 1.
  • EXAMPLE 1 Determination of the active metabolite (LI) in human plasma by liquid chromatography-tandem mass spectrometry
  • the active metabolite (TT) is added in 20 ⁇ l of phosphate buffer, pH 7.2 to 0.5 ml of analyte-free plasma.
  • the amounts of analyte added are 0.100, 0.250, 0.500, 1.00, 2.50, 3.75, 5.00, 7.50 and 12.5 ng.
  • the 2500 pg of internal standard (R)-N-[4-(l,4,5,6-tetrahydro-4-ethyl-6- oxo-3-pyridazinyl)phenyl]acetamide is added in 20 ⁇ l of phosphate buffer, pH 7.2. The mixture is vortexed for 1 minute and left standing for 15 minutes.
  • the calibration samples are alkalised with 50 ⁇ l of 0.1 M sodium hydroxide and vortexed for 20 seconds.
  • the calibration samples are extracted with 5 ml of ethyl acetate:hexane (8:2) by vortexing for 3 minutes. After centrifugation for 7 minutes the organic layer is separated and concentrated at 40 °C using Turbo Vap evaporator.
  • 200 ⁇ l of ethyl acetate :hexane (8:2) is added, vortexed for 1 minute and concentrated at 40 °C using TurboVap evaporator.
  • the samples are processed as described above but the first buffer addition is analyte-free.
  • Analyses are performed using a PE Sciex API 300 tandem quadrupole mass spectrometer equipped with a heated nebulizer interface.
  • a Hewlett-Packard HP1090L system is used for HPLC.
  • the column applied is a LiChrosorb RP-18 reversed phase column (250 x 4 mm TD, 10 ⁇ m particles, E. Merck).
  • the mobile phase consists of methanol-2 mM ammonium acetate pH 5, (60:40 v/v).
  • the flow-rate is 1 ml/min. An aliquot of 100 ⁇ l of extract is injected into the liquid chromatographic column.
  • the column eluent is flowed into the mass spectrometer without a split.
  • the discharge needle current is set at 4 kV.
  • Nebulizer gas pressure (nitrogen) of 5 bars is used.
  • the interface heater is set at 500 °C.
  • Orifice plate voltage is 25 V. Positive ions are sampled into the quadrupole mass analyser.
  • Determinations are carried out by using the selected reaction monitoring technique.
  • the first quadrupole filter of the mass spectrometer, Ql is set to pass the protonated molecules at m/z 246 for active metabolite (E) and m/z 260 for internal standard for collision-induced fragmentation in Q2.
  • the respective product ions, at m z 204 and m/z 218, are then allowed to pass Q3 for monitoring.
  • a dwell time of 200 ms and a pause time of 100 ms are used.
  • the selected reaction monitoring chromatograms are recorded using a PE Sciex API 300 Data System.
  • Peak area ratios of analyte and its internal standard are plotted against concentrations. Determination of calibration curve equations and concentrations of unknown samples are carried out with the PE Sciex API 300 Data System and the PE Sciex MacQuan 1.4 programme. The limit of quantitation is 0.200 ng/ml. The calibration curve for active metabolite (LJ) is prepared.
  • TT active metabolite
  • Figures 1 and 2 show a calibration plasma sample and a post-dose plasma sample from a volunteer.
  • Levosimendan was administered to heart failure patients for 7- 10 days in oral formulations of levosimendan (0, 0.25, 0.5, 1, 2 and 4 mg q.i.d).
  • the plasma level of metabolite (TT) and the heart rate change was measured 4 h after the last dose.
  • the correlation between the mean change in heart rate after 7-10 days treatment ( ⁇ HR, beats/min) and plasma level (ng/ml) of metabolite (IT) is shown in Fig. 3.

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Abstract

The invention relates to a method for monitoring and/or assessing the tolerability of levosimendan administration, particularly oral administration, in patients. The method comprises determining the plasma level of the active metabolite (II) of a patient after levosimendan administration. Levosimendan is useful in the treatment of congestive heart failure.

Description

A METHOD FOR MONITORING THE TOLERABΓLITY OF LEVOSIMENDAN ADMINISTRATION
Technical field
The present invention relates to a method for monitoring and/or assessing the tolerability of levosimendan administration, particularly oral administration, in patients. Levosimendan, or (-)-[[4-(l,4,5,6-tetrahydro-4-methyl-6-oxo-3-pyridazinyl)phenyl]- hydrazono]propanedinitrile, is useful in the treatment of congestive heart failure.
Background of the invention
Levosimendan, which is the (-)-enantiomer of [[4-(l,4,5,6-tetrahydro-4-methyl- 6-oxo-3-pyridazinyl)phenyl]hydrazono]propanedinitrile, and the method for its preparation is described in EP 565546 Bl. Levosimendan is potent in the treatment of heart failure and has significant calcium dependent binding to troponin. Levosimendan is represented by the formula:
Figure imgf000003_0001
The hemodynamic effects of levosimendan in man are described in Sundberg, S. et al., Am. J. CardioL, 1995; 75: 1061-1066. Pharmacokinetics of levosimendan in man after i.v. and oral dosing is described in Sandell, E.-P. et al., J. Cardiovasc. Pharmacol., 26(Suppl.l), S57-S62, 1995. The use of levosimendan in the treatment of myocardial ischemia is described in WO 93/21921. Clinical studies have confirmed the beneficial effects of levosimendan in heart failure patients.
Oral administration of levosimendan has proved to be difficult. The elimination half-life of levosimendan in human is short, about 1 h. Therefore, using conventional immediate release oral formulations levosimendan should be administered frequently during the day. The gastrointestinal absorption of levosimendan is also rapid. Therefore, using immediate release oral formulations high peak plasma concentrations of levosimendan are reached rapidly and abruptly, typically within 1 hour. High plasma concentrations of levosimendan tend to increase heart rate which is an undesired effect in heart failure patients.
Compositions which release drug over an extended period of time provide many advantages over conventional rapid release compositions. Such advantages include smaller variation of drug concentrations in plasma and, as a result, steady therapeutic response, reduced frequency of administration and reduction of side effects.
However, attempts to administer levosimendan orally in extended release preparations have been disappointing due to unexpected tolerability problems. Undesired effects such as severe headache, increased heart rate and palpitation are frequently observed in certain patients. The tolerability varies a lot between individuals making the dose finding difficult.
Therefore, there is a need for methods for monitoring and/or assessing the tolerability of levosimendan administration, particularly oral administration, in patients.
Summary of the invention
It has been found that levosimendan is susceptible to metabolization in the lower gastrointestinal tract, in particular in the large intestine, by the intestinal bacteria. Such metabolic route results ultimately in the formation of an active first-pass metabolite, (R)-N-[4-(l,4,5,6-tetrahydro-4-methyl-6-oxo-3-pyridazinyl)phenyl]acetamide (LI) whose elimination half-life is substantially longer than that of levosimendan. The accumulation of the active metabolite has been found to be the cause of the tolerability problems associated with the oral administration of the extended release preparations of levosimendan. The discovery of the active metabolite and its formation route makes it now possible to use this metabolite as a tool in monitoring and/or assessing the tolerability of levosimendan administration in patients.
Brief description of the drawings
Fig 1 shows a calibration sample for the active metabolite (H) from a volunteer as determined by liquid chromatography-tandem mass spectrometry.
Fig. 2 shows a post-dose plasma sample for the active metabolite (LI) from a volunteer as determined by liquid chromatography-tandem mass spectrometry.
Fig. 3 shows the correlation of heart rate change to the plasma level (ng/ml) of metabolite (LI) in heart failure patients. Detailed description
The present invention provides a method for monitoring and/or assessing the tolerability of levosimendan administration, particularly oral administration, in a patient which method comprises determining the plasma level of metabolite (TT) of a patient after levosimendan administration.
The plasma level of metabolite (TT) correlates well with the occurrence of undesired effects such as severe headache, increased heart rate and palpitation. In the optimal levosimendan treatment of heart failure patients the steady-state plasma level of metabolite (LJ) should be less than 20 ng/ml, preferably less than 10 ng/ml.
Since the accumulation of the active metabolite is slow, the plasma level of metabolite (LI) is preferably determined at least 48 hours after levosimendan administration. Preferably, the plasma level of metabolite (LJ) is determined in a steady- state situation.
The method of monitoring and/or assessing the tolerability of levosimendan administration is particularly important when controlled/extended release formulations of levosimendan are administered.
Levosimendan may be administered monthly, weekly or daily or several times a day depending upon the patient's needs. The daily dosage of levosimendan in man in oral administration is from about 0.1 to 20 mg, typically from about 0.5 to 10 mg, more typically from about 1 to 4 mg, in one daily dose or divided into several doses per day. The dosage depends e.g. on the age, body weight and condition of the patient. Preferably levosimendan is administered daily 1 - 3 times a day.
During the oral levosimendan treatment the plasma level of metabolite (TT) is determined at least 48 hours after levosimendan administration and, preferably, after the steady-state plasma level of (LI) has been reached. Typically, in a daily treatment, the steady-state plasma level of (TT) has been reached in about 7 - 14 days from the first dose. In heart failure patients having impaired renal function the plasma levels of metabolite (Ti) may vary considerably between patients regardless of the levosimendan dose. Preferably the plasma level of metabolite (LT) is monitored over the whole oral treatment period, e.g. by taking a blood sample from the patient periodically, e.g. daily, weekly, biweekly or monthly. Monitoring of the plasma levels of (TT) allows for individual dose adjustment in order to minimize variability amongst patients. The plasma level of the active metabolite (LI) can be measured according to any method known in the art. An example of a method for determining the plasma level of metabolite (TT) described in detail in Example 1.
EXAMPLE 1. Determination of the active metabolite (LI) in human plasma by liquid chromatography-tandem mass spectrometry
Preparation of calibration samples
The active metabolite (TT) is added in 20 μl of phosphate buffer, pH 7.2 to 0.5 ml of analyte-free plasma. The amounts of analyte added are 0.100, 0.250, 0.500, 1.00, 2.50, 3.75, 5.00, 7.50 and 12.5 ng. After being vortexed for 20 seconds and left standing for 10 minutes, the 2500 pg of internal standard (R)-N-[4-(l,4,5,6-tetrahydro-4-ethyl-6- oxo-3-pyridazinyl)phenyl]acetamide is added in 20 μl of phosphate buffer, pH 7.2. The mixture is vortexed for 1 minute and left standing for 15 minutes. The calibration samples are alkalised with 50 μl of 0.1 M sodium hydroxide and vortexed for 20 seconds. The calibration samples are extracted with 5 ml of ethyl acetate:hexane (8:2) by vortexing for 3 minutes. After centrifugation for 7 minutes the organic layer is separated and concentrated at 40 °C using Turbo Vap evaporator. When the calibration samples are dry, 200 μl of ethyl acetate :hexane (8:2) is added, vortexed for 1 minute and concentrated at 40 °C using TurboVap evaporator. After that 200 μl of methanol-2 mJVI ammonium acetate (1:1) is added, the calibration samples are vortexed for 1 minute and left standing for 5 minutes. After centrifugation for 7 minutes the supernatant is transferred into an unused conical autosampler vial for liquid chromatographic-tandem mass spectrometric analysis.
Preparation of samples
The samples are processed as described above but the first buffer addition is analyte-free.
Liquid chromatography-tandem mass spectrometry
Analyses are performed using a PE Sciex API 300 tandem quadrupole mass spectrometer equipped with a heated nebulizer interface. A Hewlett-Packard HP1090L system is used for HPLC. The column applied is a LiChrosorb RP-18 reversed phase column (250 x 4 mm TD, 10 μm particles, E. Merck). The mobile phase consists of methanol-2 mM ammonium acetate pH 5, (60:40 v/v). The flow-rate is 1 ml/min. An aliquot of 100 μl of extract is injected into the liquid chromatographic column.
The column eluent is flowed into the mass spectrometer without a split. The discharge needle current is set at 4 kV. Nebulizer gas pressure (nitrogen) of 5 bars is used. The interface heater is set at 500 °C. Orifice plate voltage is 25 V. Positive ions are sampled into the quadrupole mass analyser.
Determinations are carried out by using the selected reaction monitoring technique. The first quadrupole filter of the mass spectrometer, Ql, is set to pass the protonated molecules at m/z 246 for active metabolite (E) and m/z 260 for internal standard for collision-induced fragmentation in Q2. The respective product ions, at m z 204 and m/z 218, are then allowed to pass Q3 for monitoring. A dwell time of 200 ms and a pause time of 100 ms are used. The selected reaction monitoring chromatograms are recorded using a PE Sciex API 300 Data System.
Quantitation and calculations
Peak area ratios of analyte and its internal standard are plotted against concentrations. Determination of calibration curve equations and concentrations of unknown samples are carried out with the PE Sciex API 300 Data System and the PE Sciex MacQuan 1.4 programme. The limit of quantitation is 0.200 ng/ml. The calibration curve for active metabolite (LJ) is prepared.
Specificity
The product ions of active metabolite (TT) and its internal standard are monitored using the selected reaction monitoring technique. The method is specific regarding the background arising from the plasma. No interfering peaks are observed in blank plasma extracts. Figures 1 and 2 show a calibration plasma sample and a post-dose plasma sample from a volunteer.
EXAMPLE 2. Correlation of heart rate change to the plasma level of metabolite (TT) in heart failure patients
Levosimendan was administered to heart failure patients for 7- 10 days in oral formulations of levosimendan (0, 0.25, 0.5, 1, 2 and 4 mg q.i.d). The plasma level of metabolite (TT) and the heart rate change was measured 4 h after the last dose. The correlation between the mean change in heart rate after 7-10 days treatment (ΔHR, beats/min) and plasma level (ng/ml) of metabolite (IT) is shown in Fig. 3.

Claims

1. A method for monitoring and/or assessing the tolerability of levosimendan administration in a patient which method comprises determining the plasma level of metabolite (TT) of a patient after levosimendan administration.
2. A method of claim 1 wherein the administration is oral administration.
3. A method of claim 1 or 2 wherein the plasma level of metabolite (TT) is determined at least 48 hours after levosimendan administration.
4. A method of claim 1, 2 or 3 wherein the determined plasma level is a steady- state plasma level of metabolite (LI).
PCT/FI1999/000330 1998-04-23 1999-04-23 A method for monitoring the tolerability of levosimendan administration WO1999056134A1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11607412B2 (en) 2019-12-16 2023-03-21 Tenax Therapeutics Inc. Levosimendan for treating pulmonary hypertension with heart failure with preserved ejection fraction (PH-HFpEF)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0383449A2 (en) * 1989-02-11 1990-08-22 Orion-Yhtymà„ Oy Pyridazinone derivatives and processes for preparing the same
WO1997035841A2 (en) * 1996-03-27 1997-10-02 Orion-Yhtymä Oy Method for obtaining pure enantiomers of a pyridazinone derivative
WO1998001111A1 (en) * 1996-07-05 1998-01-15 Orion-Yhtymä Oy Transdermal compositions containing levosimendan

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0383449A2 (en) * 1989-02-11 1990-08-22 Orion-Yhtymà„ Oy Pyridazinone derivatives and processes for preparing the same
WO1997035841A2 (en) * 1996-03-27 1997-10-02 Orion-Yhtymä Oy Method for obtaining pure enantiomers of a pyridazinone derivative
WO1998001111A1 (en) * 1996-07-05 1998-01-15 Orion-Yhtymä Oy Transdermal compositions containing levosimendan

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
LEHTONEN, LASSE ET AL: "Safety of levosimendan and other calcium sensitizers", J. CARDIOVASC. PHARMACOL. (1995), 26(SUPPL. 1), S70-S76, XP002110568 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11607412B2 (en) 2019-12-16 2023-03-21 Tenax Therapeutics Inc. Levosimendan for treating pulmonary hypertension with heart failure with preserved ejection fraction (PH-HFpEF)
US11701355B2 (en) 2019-12-16 2023-07-18 Tenax Therapeutics, Inc. Levosimendan for treating pulmonary hypertension with heart failure with preserved ejection fraction (PH-HFpEF)
US11969424B2 (en) 2019-12-16 2024-04-30 Tenax Therapeutics, Inc. Levosimendan for treating pulmonary hypertension with heart failure with preserved ejection fraction (PH-HFpEF)

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