Note: Descriptions are shown in the official language in which they were submitted.
~2416~4~
A drug kit or drug composition
The present invention relates to a drug kit or drug composition
for use in preventing and treating ischaemic cell damage.
When circulation of the blood collapses and ischaemia occurs
in peripheral body organs, particularly in the brain, a large
number of pathophysiological changes take place. In present
clinical practice it is only possible to treat measurable
pathophysiological changes, for example changes in blood
volume, impaired-cardiac function, central acidosis, etc.
In such cases each change has been treated individually and
it can be sP~id'generally that present day therapy for the
resuscitation of an organ is mainly directed towards re-
establishing blood circulation.
The present invention is based on the concept that incurabletissue damage can be caused as a result of unfavourable con-
ditions created when re-establishing the blood circulation
to a body organ.
According to one aspect of this concept the transportation of
calcium into and out of,a cell is of great significance. The
transportation of calcium into and out of a cell normally
takes place while maintaining externally of the cell a calcium
concentration which is 1000 times greater than the calcium
concentration inside the cell. When a deficiency in energy
occurs as a result of ischaemia, the calcium gradient cann~t
be maintained, and calcium will consequently leak into the cell.
Calcium is taken up in the cell by the mitochondria, resulting
in serious disturbances in energy production. Wh~n blood again
starts to flow, calcium will enter the cell in still greater
quantities, while transportation of calcium from the cell is
impaired due to the fact that the build-up of energy in the
cell is inhibited by the high calcium content thereof. This
greatly increases the load on the mitochondria, which can
lead to incurable cell damage and cell death.
6~9
According to another aspect of the concept there occurs during
the ischaemic period a gathering of degradation products,
such as hypoxanthine, which when oxygen is supplied in connec-
tion with the re-establishment of circul~tion are converted
by certain enzymes, such as xanthine oxidase, in processes
which produce free hydroxyl radicals as a secondary product,
possibly via O2-radicals. Those enzyme systems which protect
the tissue from the hydroxyl radicals are not able herewith
to deal with the radicals at the rate in which they are formed,
which can lead to damage of blood vessels for example.
On the basis of these concepts concerning incurable tissue
damage, there is now provided a drug kit or drug composition
which provides a better result and enables persons who are
subjected to the risk of ischaemic cell damage to be treated
in a simplified manner.
The drug kit or drug composition according to the invention
is characterized in that it comprises
a) at least one plasma volume expander;
b) at least one low molecular, physiologically
- acceptable hydroxyl radical scavenger;
c) at Ieast one physiologically acceptable and
water soluble magnesium salt; and
d) at least one calcium blocking organic compound
dissolved in a carrier, either per se or in one or more com-
bina~ions.
The invention is described hereinafter with reference to a
drug kit intended for-single-unit administration, although
the invention also relates to-different stock solutions
which might come into question.
The plasma volume expander used may be a physiologically
acceptable high molecular substance known per se in the expan-
sion of blood plasma volume. These substances have an average
molecular weight Mw (weight average value) which is higher
than 10,000 Daltons, e.g. higher than 15,000 and preferably
higher ~an 30,000 and lower than 400,000 and preferably
3 ~-z,~
lower than 300,000 Daltons. It is well known in the art that
the average molecular weight Mw chosen depends on the high
molecular substance used. Examples of such plasma expanders
' are plasma-albumin and substances based on dextran, starch
derivatives or gelatine derivatives. The dextran products
normally have an average molecular weight Mw within the range
of 30,000 to 80,000 Daltons. Examples of starch derivatives
for this purpose include hydroxyethyl starch ha~ing an average
molecular weight Mw within the range of 40,000 - 400,000
Daltons, e.g. in the order of 200,000 Daltons. A number of
different gelatine derivatives of varying average molecular
weights ~ are also used for this purpose. (A review of some
plasma volume expanders is found, for example, in the book
"Blood Replacement" by U.F. Gruber, Springer Verlag, Berlin-
Heidelberg-New Yo~k 1969). Of these plasma volume expanders,
those based on dextran are primarily preferred.
The concentration of plasma volume expander in the solution
in which it is present-is'chosen so that subse~uent to being
optionally mixed wi~h one or more solutions incorporated
in the kit, the soiution injected into the patient will have
a plasma-volume-expander concentration which is normal in
the use of the substance in question. The plasma volume expander
solution of the invention usu~lly has a concentration of 1-15 g/
100 ml, su-ch as'2-12 g/100 ml, for exam~le 3-10 g/100 ml. ' '
A common requirement of the hydroxyl radical scavengers which
can be used in accordance with the invention is that they
are physiologically acceptable and have a molecular weight
beneath 10,000 Daltons, preferably beneath 1,000 Daltons.
Hydroxyl radical scavengers which have a molecular weight
above 10,000 Daltons as a rule have a poor effect. A suitable
hydroxyl radical scavenger is soluble in water at physio-
logical pH and ion strengths. It normally includes a func-
tional structure selected from-~aromatic o~ aliphatic thiol
(-SH~, alcoholic and phenolic hydroxyl t-oH) and nitrogen-
containing structures, such as primary amine ! -NH2) secondary
amine l-NH-) and imine (=NH). The hydroxyl radical scavenger
is advantageously selected from the group comprising physio-
logically acceptable sugar alcohols, monosaccharides, oligo-
saccharides, amino acids which contain mercapto groups, and
methionine and histidine. Among the group of sugar alcohols,
mannitol -is the primary choice, because it is able to function
simultaneously as a diuretic and an anti-oedema agent. Other
sugar alcohols of interest in this context are sorbitol and
xylitol. Examples of physiologically acceptable monosaccha-
rides are glucose and fructose, and of oligosaccharides malto-
oligosaccharides and isomalto-oligosaccharides (which can
be obtained by means o partial hydrolysis of starch and
dextran respectively), e.g. maltose. Cysteine is an example
of amino acids which contain mercapto groups.
The hydroxyl scavenger used is preferably a combination of
at least one sugar alcohol and at least one amino acid according
to the above, particularly a combination of mannitol and
L-methionine, or of mannitol, L-methionine and histidine.
The concentration of hydroxyl radical scavenger is determined
by-the specific substance in question and by the amount it
is desired to administer. It is always so high as to enable
a therapeutically active ~uantity to be administered when
the kit is used. The drug kit or drug composition according
to the invention may thus contain from 1 g up to 150 g hydroxyl
radical scavenger~ The range of 1-10 g is particularly appli-
cable in the case of methionine and histidine and a range of
5-150 g in the case of-sugar alcohols, calculated per occasion
of treatment.
Magnesium salt present in the compQsition comprises one or
more salts from the group water-soluble, pharmaceutically
acceptable magnesium salts. Examples of magnesium salts which
are thus comtemplated are magnesium sulphate and magnesium
chloride. ~a:gnesium chloride is particularly preferred. Water-
soluble magnesium salts are present in the composition
according to the invention in quantities corresponding to
5-100 mmol Mg2+, calculted per occasion of treatment.
5 ~2~4~
The organic compounds acting as calcium blockers are normally
of low molecular weight, with a molecular weight beneath
2000 Daltons. They are deined by their ahility to prevent
the migra~ion of calcium ions into cells. Cf. "Calcium
Blockers" (edited by Flaim~ S.F. et al; Urban and Scharzen-
berg. Baltimore-Munich, 1983). The compounds in question
may be of highly different structure, niphedipine, nimodipine,
verapamil, diltiazem, lidoflazine, flunarazine and analogous
compounds can be mentioned by way of example. The calcium
blockers used in accordance with the invention may be soluble
in water and/or in fat. Verapamil(5- ~(3,4-dimethoxyphenylethyl)
methylamino~ -2-(3,4-dimethoxyphenyl)-2-isopropylvaleronitrile)
is an example of a water-soluble calcium blocker, while an
example of a fat-soluble calcium blocker is lidoflazine(4-
[4,4-bis(4-fluorophenyl)butyl~ -N-(2,6-dimethylphenyl)-1-piper-
azine acetamide). When a fat soluble Galcium blocker is used
in accordance with the invention, it is advantageously in-
cluded in the kit as a component separate from the plasma
volume expander. According to one aspect of the invention,
this enables lidoflazine to be administered in a separate in-
jection when using the drug kit. In this variant of the in-
vention, the fat-soluble calcium klocker may be dissolved
in, for example,:
I. A mixture of water and ethanol in an amount which is
physiologically acceptable for the purpose. When the calcium
blocker has the nature of an amine, the mixture can be
acidified, to increase solubility. It is essential in this
respect-that acidification of the mixture is adapted to the
pH and buffer capacity o~ the remaining kit components to
be used on the occasion-of the treatment. The mixture is
advantageously acidified with aceti~ acid, hydrochloric acid,
or some other physiologically acceptable acid. The mixture
may also contain glycerol.
II. Physiologically acceptable fat emulsions used for paren-
teral nutrition (a number of such emulsions are described,
inter alia, in patent literature; cf. for example the U.S.
6 ~ Z ~
Patent Specification No. 4,168,308).
A usable p~oduct in this connection is retailed under the name
Intralipid~by Apoteksvarucentralen Vitrurn AB, Stockholm,
Sweden. This product contains fractionated soya oil in an
amount of 100 or 200 mg/ml, fractionated egg-phospholipides
(as stabilizer) in an amount of 12 mg/ml, and glycerol in
an amount of'25 mg/ml, with the remainder sterile water.
III. Physiologically acceptable emulsions of fluorinated
hydrocarbons, which are administered parenterally due to
their ability to dissolve and transport oxygen gas.
The amount of-calcium blocker included in the kit varies from
substance to substance. Calculated per occasion of treatment
it is normally included in amounts of from 1 to 300 mg; a
particular value for lidoflazin0 is from 10 to 200 mg.
The carrier or vehicle in which the active kit somponents
can be dissolved is physiologically acceptable and contains
water. It may optionally be buffered'with a physiologically
acceptable bu'ffer substance to a pH-value and an ion strength
such that the total efect of that inténded to be administered
is physiologically acceptable. This means that in the selection
of a suitable-buffer systemj attention is paid to all compo-
nents included in ~e kit or the composition according to
the invention. Examples of buffer systems include trometamol
buffers, carbonate buffers,' phosphate buffers, histidine
buffers, acetate buffers and combinations thereof. According
to the invention a buffer system may be included as a solutlon
separate from the solution containing the plasma volume
expander, hydroxyl radical scavenger, magnesium salt. A se-
- parate buffer system shall be used when acidose is present.
It shall be capable of restoring the blood of the patient in
question to a pH-value of from 7.0 to 8.0, preferably the
physiological pH-value 7.4. The buffer capacity lies in the
region of 25-300 mmol, preferably 50-200 mmol. In practice
this means that a separate buffer system shall have a pH-value
7 ~ 2~6~
in the range of 7.0 - 10.0, preferably 7.4 - 9.2.
The drug kit or composition according to the invention pre-
ferably also include's a diuretic agent, particularly an
osmotic diuretic agent, and/or an anti-oedema substance.
Since in addition to being an hydroxyl radical scavenger,
mannitol is also able to fulfil the function of both a
diuretic and an anti-oedema substance, mannitol is a pre-
ferred substance in the present context. Sorbitol or gly-
cerol can be used as a diuretic agent, either instead of ortogether with mannitol. The quantities in which a diuretic
agent and anti-oedema substance is used is dependent on the
substance utilized, and may thus vary within wide limits.
In the case o~ an osmotic diuretic agent, the quantities used
may lie within the range 5-150 g, otherwise 0.1-200 mg. In
the case of the anti-oedema substance a corresponding range
may be 5-150 g.
It may also be of advantage~to incorporate in the kit or the
composition according to the invention an xanthine oxidase
inhibitor, such as allopurinol for example, (50 mg - 5 g, de-
pending on which is chosen), and/or a superoxide radical
scavenger, such as superoxide dismutase for example, and/or
an hydrogen peroxide inactivator,such as catalase for example,
and/or a substance which binds iron in a solid complex, such
as desferrioxamine or diethylenetriamine-pentaacetic acid
or ethylenediamine-di(o-hydroxyphenylacetic acid)~ or a phytic
acid derivative.
The quantities quoted above in respect of the diuretic agent,
anti-oedema substance and-xanthine-oxidase inhibitor apply
to each occasion of treatment.
The active components included in the drug kit or drug compo-
sition are present in the form of a single solution or a plu-
rality of solutions. Precisely how they are combined is de-
termined, inter alia, on the grounds of solubility and sta-
bility, even though for practical reasons the aim is to place
~z~
them in a common solution. For example, in accordance ~7ith one
advantageous variant, the plasma volume expander hydroxyl radical
scavenger, magnesium salt and calcium blocker are selected so as to be
compatible with one another in solubilized form and with the desired
pH-value of the solution to be administered. Similar considerations
are applicable to remaining active components such as the anti-oedema
substance, diuretic agent, xanthine-oxidase inhibitor, superoxide
radical scavenger, hydrogen peroxide inactivator and iron-binding
substance.
On the basis of those studies carried out hitherto, the embodiment
most preferred has a solution (A) which contains plasma volume
expander, hydroxyl radical scavenger and magnesium salt; a solution
(B) which contains a buffer system and a solution or dispersion (C)
which contains a fat-soluble calcium blocker. In this embodiment, the
remaining active components are placed in one of the solutions A, B or
C. For example, if allopurinol is chosen as the xanthine-oxidase
inhibitor, it can be added to the buffer solution B for reasons of
solubility. If the kit does not include such a solution, it may be
necessary to choose another xanthine-oxidase inhibitor.
The various solutions included in a drug kit according to the inven-
tion (and in certain cases the dispersion of organic calcium blocker)
may have the form of sterile storage solutions from which a suitable
quantity of the separate solutions or dispersion is taken on each
treatment occasion; preferably, however, the kit is made up with
dosages suited to the purpose, each dosage containing therapeutically
active quantities of the substances in question. In this latter case a
solution (A) according to the aforegoing can be packed into units of
100-1000 ml, normally 500 ml, a solution (B) packed in units of 10-100
ml, preferably 25-100 ml, and a solution or dispersion (C) packed in
units of 5-50 ml, preferably 10-30 ml. The units can be poured into
plastic sachets, glass or plastic bottles, ampoules, syringes etc..
The exact choice varies from case to case, and is determined, in~er
alia, by practical considerations. It can be mentioned by way of
example that the solution C is advantageously placed in an ampoule or
disposable . . . . . . . . . . . . . . . . . . . . . . . . .
'~'
~2~
syringe.
The concentration in which the active components are present
are selected so as to maintain the mutual proportions between
the aforementioned quantities. In the aforesaid preferred
embodiments, the concentration of hydroxyl radical scavenger
and magnesium salt corresponds to the aforementioned quantities
per 500 ml of solution. The same applies to the calcium
blocker, when it is incorporated in the same solution as these
two substances. When it is present in a separate solution (C),
the calcium blocker concentration may be from 10 to 100 times
greater than in the previous case, due among other things to
the solubility conditions.
When calculated on the basis of a patient weighing 70 kg, the
kit components are normally administered to the patient in a
total solution volume of 500-600 ml.
When using a drug kit according to the invention in which the
calcium blocker is included as a separate unit (C), this unit
is the first to be injected into the patient. It is desirable
that this injection can be given relatively quickly. In those
cases where métabolic acidose prevails, as with a cardiac
arrest for example, solution (B3 i5 used to corrent the pH of
the patient. The solution (B) may be mixed with the solution
(A) immediately or shortly before being used. The mixture, or
the solutions (A) and (B) each per se, is or are then adminis-
tered to the patient as soon as possible after having injectedthat patient with (C). In the absence of metabolic acidose,
only solution (A) is administered.
When using a drug composition according to the invention in
which a plasma volume expander, an hydroxyl radical scavenger,
magnesium salt and a calcium blocker are present in a common
solution separate from a buffer solution (B), this common solu-
tion is injected into the patient separately or in mixture with
(B). The solution (B) is only used in the case of metabolic
acidose.
: .
1 0 ~ 64~
The drug kit accordiny to the invention is intended for use
primarily in acute resuscitation, such as in the event of
a cardiac arrest or in other situations in which blood
circulation collapses and ~he brain is subjected to ischae-
mia. The drug kit can also be used in various kinds oftrauma in the central ner~ous system, cerebral haemorrhage,
apoplectic strokesl su~arachnoidal bleeding, or in the case
of intracranial vessel surgery, where blood vessels must be
temporarily closed. The drug kit can also be used with
ischaemic conditions in other body organs, such as the heart,
kidneyst intestines and skeleton muscle, in conjunction with
shock, trauma, embolies and heart attacks, and also in sur-
gical operations, such-as heart surgery, vessel reconstruction
and organ transplantation.
The drug kit can also be used as a~perfusion
solution and preserving solution for body organs in, for
example, cardioplegy or-organ transplantation.
The invention also relates to a-method of treating the afore-
said conditions. In such a treatment the components of the
kit are administered in any of the ways described above.
The invention will now be described with reference to a number
o working examples.
EXEMPLE
Preparation of a drug kit
Solution A
15 g dextran having an average molecular weight (Mw) o~ about
60 000, 4.0 g MgCl2 (anhydrous), 25 g mannitol, 5 g L-methio-
nine, and 5 g L-histidine were dissolved in 500 ml distilled
water. The resultant solution was sterilized by sterile fil-
tration and poured into a 500 ml sterile plastics bag, whichwas then sealed under aseptic conditions.
j
6~
Solution B
There were used for this solution 50 ml of a conventional
commercial buffer solution having a pH of 9.2 and containing
20 g trometamol with a buffer capacity of 150 mmol (Adde
THAM form Pharmacia Infusion AB, Uppsala, Sweden).
Solution C
-
80 mg lidoflazine were dissolved in 1.0 g ethanol (99.5%),
0.1 g concentrated acetic acid and 1.5 g glycerol, and was
diluted up to 10 ml with distilled water. The solution was
sterilized by sterile filtration ana poured into a 1~ ml
ampoule lmder aseptic conditions.
The solutions A, B and C were then packed in a box, as a unit.
EXAMPLE 2
Pharmacological tests
The tests were carried out with a rat model, which gives an
incomplete cerebral ischaemia with a cortical flow < 5% of
the normal flow, and a flow in the brain stem which is about
30% of the normal flow.;This is effected by squeezing the
two carotid arteries while simultaneously lowering the blood
pressure to 50 mm Hgj by bleeding. The method has been de-
~5 scribed by Nordstrom C.I-I. and Siesjo B.K., Stroke 9, 327-335
(1978).
Wistar-rats weighing 300-400 g and fasted overnight were used
in the tests. The rats were anaesthetized with 4% Fluothane ~
(ICI-Pharma AB, Gothenburg, Sweden), 30% 02/70% N~O, intubated
and connected to a respirator. The vena jugularis externa
was uncovered. Celocurine ~5 mg/kg) was injected and a cathe-
ter was placed in vena cava supe~ior. Catheters were also
placed in the tail artery and in a tail vein for measuring
blood pressure and infusion, respectively. EEG-electrodes
were applied and finally 5 ml 0.9% NaCl were administered intra-
peritoneally and 100 IU heparin~ intravenously. The supply of
Fluothane ~ was cut-off, whereafter blood gases, pH and the
sugar content of the blood were measured for a period of a-t
least 30 minutes. It was endeavoured to obtain a pH in the
region of 7.35 - 7.40, PCO2 Of 4.67 - 5.50 kPa, and PO2 of
' 11.0 - 18.0 kPa, and a bloodsugar content in the region
3.0 - 8.0 mmol/l. If these criteria were not attained, the
animal was excluded.
The following procedure was undertaken in order to create
ischaemia:
A solution of trimethaphan-D-cam~harsulphcnate in sterile water
(15 mg/ml, Arfonad ~ from Hoffmann-La Roche & Co AG, Basle,
Switzerland) was administered intravenously, until the
average blood pressure was 80 mm Hg, whereafter the two carotid
arteries of respective animals were shut-off and blood was
drained from the animals through respective catheters in
vena cava superior until an average blood pressure of 50 mm Hg
was reached.
~he EEG was recorded contin~usly during this time period, and
the ischaemic period was taken to commence when an isoelec-
tric EEG was obtained. Subsequent to an ischaemic period of
10 mins, the infusion of lidoflazine in the treatment group
was commenced. Of a total dosage of 1.0 mg in one ml of a
~5 physiological sodium ~h~or~db solution, half was administered
during the ischaemia and the remainder after 5 minutes re-
circulation. A corresponding volume of physiological sodium
chloride solution was administered to a control group.
Infusion of an aqueous solution containing 3.5~ albumin,
10% mannitol, 2~ L-methionine, 92.2 mM`magnesium
chloride and 0.5 M Tris (percentages given in w/v~, was
commenced during the last two minutes of the ischaemic period
and was continued for two minutes during the recirculation
phase. A total of 2 ml were injected. The blood pressure
3~ was monitored during the infusion period and adjusted when
necessary, by bleeding the animal or infusing blood there-
into. The rats were left in the respirator until they began
to waken, whereupon they were ventilated for two minutes
with 100% axygen gas and the respiratQ~ then disconnected.
Tracheal tubes and oxygen masks were left in position until
~246449
stable breathing was observed.
Of 10 test animals in each group, the mortality of the con-
trol group was 60%. The cor~esponding figure in the group
treated with a drug kit according to the invention was 20%.
No significant differences were observed with regard to
average arterial blood pressure, blood gas or blood sugar.
With regard to the pH of the blood, it was observed that
the blood-pH of the animals in the group treated with a drug
kit according to the invention fell after the ischaemic
period to a lesser extent than that of the animals in the
control group, this being attributed to the buffer capacity
of the drug kit accordin~ to the invention.
