Note: Descriptions are shown in the official language in which they were submitted.
Background of the Invention
1. Field of the Invention
_
This invention relates to stable, concentrated
solutions of cisplatin in aqueous polyethylene glycol,
methoxy polye~hylene glycol, or mixtures thereof, con-
taining a source of chloride ion~
2. Description of the Prior Art
The platinum compounds are a unique group of
compounds in the antineoplastic group of agents. They
were first noted to have an antibiotic effect by Rosenberg
and his colleagues in 1965 lRosenberg, B. et al., Nature
(London), 205, 698-69g (1965)] and subsequently found by
Rosenberg and his colleagues ~o be potent antitumor agents
in animals [Rosenberg, B. et al , Nature (London), 222,
385-386 (1969)].
Structurally they represent a complex formed by
a central atom of platinum and surrounded by various
arrangements of chlorine atoms or ammonia groups in
either a cis or trans planar relationship. Two of the
more commonly studied platinum compounds are diagrammed
below:
3--
C1
Cl NH3 Cl ¦ NH3
Cl NH3 Cl I NH3
Cl
Cis-Platinum (II) Cis-Platinum ~IV)
Diamminedichloride Diamminetetrachloride
As can be seen, the compound cis-platinum tII~ diammine~-
dichloride has all its chloro and amino gxoups in a single
plane. This compound, now known by the United States
Adopted Name (USAN) cisplatin, has been synthesized acGord-
ing to the following reaction:
NH4Cl
K2[PtC14~ + 2NH3 ~- ~ cis-~pt(NH332cl2] ~ 2KCl
[see Kauffman, G. B~ et al., in Inor~anic Svnthesist J.
_ _ .. .
Kleinberg (Ed.), pages 239-245, McGraw-Hill Book Co., Inc.,
New York, 1963].
Breusova-Baidala, Y. G. et al., in Akademia
Nauk SSSR, No. 6, pp. 1239-1242 (June 1974), discuss the
slow isomerization of cis-platinum (II) diamminedichloride
in aqueous solution to the trans form.
Reishus, J. W. and Martin, D. S~, in Journal of
the American Chemical Society, 83, 2457-2462 (1961),
describe the acid hydrolysis of cisplatin at 25C and
35C. These studies were conductPd in aqueous solutions
at concentrations of 1.5 x 10 M, 2.5 x 10 M and 5.0 x
10 3 M, which correspond to 0.45~ 0.7S and 1.5 mg/ml,
respectively. The authors state that there was some
~.6~
ambiguity in locating the origin (i.e "zero point") for
the hydrolysis curves because the samples required from
lO to 30 minutes to dissolve completely even at those low
concentrations.
Rozencweig, M. et al., in Annals of Internal
__
Medicine, 86, 803-812 (1977), review the results of
various preclinical and clinical investigations of the
use of cisplatin in experimental tumors in animals as
well as various type~ of human tumors. They point out
that the investigational drug, available to qualified
investigators through the Investigational Drug Branch of
the Cancer Therapy Evaluation Program of the National
Cancer Institute, was supplied as a white lyophilized
powder in vials containing 10 mg of cisplatin, 90 mg of
sodium chloride, lO0 mg of mannitol (U.S~P.) and
hydrochloric acid for p~ adjustment. When reconstituted
with 10 ml of sterile water for injection (U~S.P.), each
ml of the resulting solution would contain 1 mg of
cisplatin, lO mg of mannitol and 9 mg of NaCl.
Talley, R. W. et al., in Cancer Chemotherapy
Reports, 57, 465-471 (1973), describe the results of
their Phase I clinical stuay of the use of cisplatin in
the treatment of 65 human patients with a wide variety of
neoplasms. As in the preceding publication, the drug was
supplied to them by the National Cancer Institute in vials
containing lO mg of cisplatin, 90 mg sodium chloride and
lO0 mg of mannitol, for reconstitution with lO ml of
sterile water.
Rossof, A. H. et al , in Cancer, 30, 1451-1456
(1972), describe the results o their use of cisplatin in
the trea~ment of 31 human patients with a variety of tumor
7~
types. They state that the drug supplied by the Naticnal
Cancer Institute was manu~actured by Ben Venue Laboratories,
Inc. and contained, per vial, 10 mg of cisplatin, 10 mg
~sic) of mannitol and 9 mg (sic) of NaCl, and that the
yellowish-white powder dissolved readily in 8-10 ml of
sterile water.
Certain information concerning the chemistry and
pharmaceutical formula~ion of cisplatin are given on pages
1-5 and 31-32 of the publication entitled "CLINICAL BROCHURE,
CIS-PLATINUN ~II) DIAMMINEDICHLORIDE (NSC~119~75) ~
Haldelsman et al., Investigational Drug Branch9 Cancer
Chemotherapy Evaluation Program9 Division of Cancer
Traatment, National Cancer Institute (Revised Au~ust 1974).
Pages 31 and 32 thereof ~oncern the formulation of cisplatin
supplied gratis by the N.C.I~ to clinicians for their
clinical evaluation in the chemotherapy of cancer and
read as follows:
PHARMACEUTICAL DATA S~EET
NSC-119875 Cis-Diamminedic~loroplatinum (II)
Dosa~e Formulation
10 mg./vial : The contents of each 20 ml. flint
vial appears as an off-white
lyophilized cake. Each vial con-
tains 10 mg. of NSC-119875; 90 mg.
of Sodium Chloride; 100 mg. o
Mannitol and Hydrochloric acid for
pH adjustment,
7~3
--6~
501ution Preparation
10 mg./vial : When reconstituted wikh 10 ml. of
Sterile Water for Injection, USP;
each ml. of the resulting solution
will contain 1 mg. of ~SC-119875,
10 mg. of Mannitol, and 9 mg. of
Sodium Chloride ha~ing a pH range
o 3~5-4-5D
Storage : The dry, ~ vials should be
stored at refri~eration temperatures
(4-8~C.).
Stability : Intact vials have a provisional
stability of one year when stored
at refrigeration temperature
(4-8C.). Stability recommendations
may be adjusted pending completion
of a two-year shelf~life studyO
Reconstitution as recommended
results in a pale, yellow solution
which is stable for not more than
one hour at room temperature t22C.)
when exposed to normal room illumina-
tion and not more than eight hours
at room temperature (22C.) when
protected from light. Reconstituted
solutions may form a precipitate
after one hour a~ refrigeration
temperature (4-8C.).
Caution : The lyophilized dosage formulations
contain no preser~atives and therefore
it is advised to discard solutions
eight hours after reconstitution.
August, 1974
ClLnical Drug Distribution Section
Drug ~evelopment Branch
~ 7 ~
Published Unitea Kingdom Patent Application No.
2021946~ describes stab7e aqueous solutions o cisplatin
having a concentration of cisplatin between about 0.1 and
lo O mg/ml and a pH in the range of 2.0 to 3.0, The
solution~ may also contain a nontoxic, pharmaceutically
acceptable, inorganic sourc2 of chloride ions, such as
sodium chloride, and an excipient such as mannitol.
_omplete Disclosure
This invention relates to stable, concen~rated,
solutions of cisplatin ha~ing concentration~ o fr~m about
2.5 to about ~5 mg/ml. More particularly, the invention
relates to stable, concentrated solutions of ci~platin
in a solvent medium comprising from about 30% to about
95~ polyethylene glycol having an average molecular weight
of from about lS0 to about 9000 or a methoxy polyethylene
glycol haYing an average molecular weight o~ fro~ about
300 to about 6000, or a mixture thereof, and from about
5~ to about 70% water, said solutions also containing at
least one nontoxic, pharmaceutically acceptable source of
chloride ion in an amount whi~h is at least about equivalent
to the amount of cisplatin pxesent in the solution, and
said solutions having a cisplatin concentration of from
about 2.5 to about 25 mg/mlO
Stable aqueous solutions of cisplat~n have been
described in published United Kingdom Patent Application
No. 2021946A. Although stable solutions containing
cisplatin concentrations up to about 1 mg/ml may be
obtained in such aqueous media at room temperature,
crystallization of the cisplatin may occur in the cold
at cisplatin concen~rations substantially above about
0.5 mgtml. Redissolving such crystallized cisplatin is
not readily accomplished by shaking a~ room temperature,
although a solution may be re-obtained by heating to
about 37C. Since shipping and storage temperatures
after sale cannot be controlled, and crystallization of
oisplatin in the vials would create an undesirable
problem for the administering physician, the maximum
practical concentration of cisplatin in such aqueous
media is a~out 0.5 mg/ml.
The cisplatin solutions of the present invention
may contain up to about 25 mg of cisplatin per mlf although
the preferred maximum is about 15 mg/ml. Solutions of
the present invention containing 15 mg of cisplatin per
ml have been maintained at a temperature of 4C for 12
months without crystallization of cisplatin. Such
solutions have also been frozen at -60C and then thawed
at room temperature with no e~idence of cisplatin pre-
cipitation~ Thus, practical solutions prepared according
to the present invention may have cisplatin concentrations
at least 30 times higher than practical aqueous solu~ions
prepared according to the prior art.
It will be appreciated that the concentrated
solutions of cisplatin provided by the present invention
will require lower shipping, storage and other cos~s per
unit dose when compared to the known aqueous solutions~
Although the known lyophilized solid form also has lower
shipping and storage costs, that saving is more than
offset by the time and expenses invol~ed in lyophiliæation.
~ 7 ~
_g_
In a preerred embodiment of the present
~nvention, the solvent medium comprises from about 80%
to about 95% (and more preferably from about 85~ to about
90~) polyethylene glycol having an average molecular
weight of from about 250 to about 1600 (and more prefer-
ably from about 250 to about 650) and from about 5% to
about 20~ (and more preferably from about 10~ to about
15%) water. In a most preferred embodLment the sol~ent
medium comprises about 90% polyethylene glycol having an
average molecular weight of from about 350 to about 450
and about 10% waterO
Preferably the solution contains from about 5
to about 20 mg of cisplatin per ml and most preferably
from about 10 to about lS mg/ml. The nontoxic, pharma-
ceutically acceptable source of chloride ion preferably
is present in a concentration of at least about two
equivalents per equivalent of cisplatin in the solution.
Concentrations as high as 50 equivalents or more of
chloride ion per equivalent of cisplatin may be utilized,
depending on the cisplatin concentration, the percentage
of water present and the particular source of chloride
ion, but such high concentrations of chloride ion usually
are neither necessary nor desirable. It will be appreciated
by those skilled in the art that, with a high cisplatin
concentration and a low water content, it would not be
possible to dissolve a suficient amount of a chloride
ion source such as sodium chloride to provide 50
equiva~ents of chloride ion per equivalen~ of cisplatin~
Further, a saturated, or nearly saturated solution of an
inorganic chloride salt would be undesirable because of
the possibility of crystallizatiDn from the solution in
the cold. In the situation set forth above, 50 equi~alents
- ~ . ~
,
--10--
of chloride ion per equivalent of cisplatin could be
obtained by the use of hydr~chloric acid as the ~ource
of chloride ion, but this might give a solution having an
undesirably high acidity, ~.e. low pH~ We haYe found
that excessively aciaic solutions are somewhat le~s
stable than more moderately acidic solution~. The p~
range of the solutions preferably is from about 1.5 to
about 4.5. We prefer to u~ilize from about 2 to about 10
equivalents of chloride ion per squivalent of cisplatLn~
and most preferably from abou~ 3 to about 7 equival~nts
o~ chloride ion per e~uivalent of cisplatin.
The chloride ion may be provided by the
addition of hydrochloric acîd, a nontoxic pharmaceutically
metallic halide such as sodium chloride, potassium
chloridet calcium chloride or magnesium chloride, or
the hydxochloric acid addition salt of a nontoxic pharma-
ceutically acceptable ~er~iary amine suGh as trie~hylamine,
or by mixtures theraof~ The preferred source of chloride
~on is hydrochloric acid, sodium Ghloride or a mixture
thereofO
Polyethylene glycols and me~hoxy polyethylene
glycols have the general formulae
H (OC~I2CEI;! ) ",OH and CH3 (CH2cH2 ) nC~3
respectively, and are commercially available as C~RBO~
Polyethylene Glycols and C~æX Methoxy Polyethylene
GlycolsO We preer to utilize the SE~ Grades of
CAR~OW~X Polyethylene Glycols, which are produced to
meet U.S.P~, N. F. and F.C.C. specification5 ~or ~ood and
dr~ applications. Typical molecular weight ranges ~or a
vari~ty of C~RBOWAX Polyethylene Glycols and CAR~OWAX
, Trademark
Methoxy Polyethylene Glycols are given in Tables 1 and 2
~able 1
~ ~ _ .
CARBOWAX Typical
Polyethylene Molecular
Glycols . Weight Range
_ _ ___ .
200 190 ~o 210
300 285 t~ 315
400 380 to ~20 ,
600 570 to 630
1000 950 to 1050
15~0 1300 to 1600
4000 3000 to 37~0
6000 7000 to 9000
_ _ . ..
Table 2
_ ~,
CARBOWAX Typical
Methoxy Molecular
Polyethylene Weight
Glycols Range
_ __ ~ . .
350 335 to 365 .
SS0 525 ~o 575
75~ 715 t~ 785
2000 . 1850 to 2150
_ __ _. . ,.
Polyethylene glycols are known to ~orm complexes
with certai~ inorganic salts. Thus, the reaction of
polyethylene glycols with ammonium cobalt thiocyanate ko
form a blue complex is the basi~ o~ one color1metric method
of determining the concentration o~ ~olyethylene glycols
~ ~6 ~ ~7 ~
in various mixtures. We believe that the unique stability
of cisplatin in the solutions o~ the present invention
may be due to a complex formed bet~een the cisplatin and
the polyethylene glycol, but this is only theory and does
not form a part of the invention. Evidence of complex
formation has been noted in our TLC procedure. Using
techniques described below, aqueous cisplatin produces a
spot at about Rf 0.65~ However, a solution of cisplatin
in 90~ Polyethylene Glycol 400 - 10% H20 (or 10% 0.5 N
HCl) gives a spot at about Rf 0.3 which streaks to about
Rf 0.65. Dilution with ~ubstantial quantities of water
appears to immediately break the complex, since dilution
of the above PEG-H20 (or HCl) solution with five volumes of
water then shows only a cisplatin spot at about R~ 0.65.
Thin Layer Chromato~raphy
Apparatus and Rea~ents
(a) TLC plates - EM Laboratories silica gel 60 plates,
Catalog No. 57~3, or equivalent.
(b) Eluent - Acetone:l N HNO3 (9:1). Prepare fresh daily.
(c) Developer - Dissolve 5.6 gm of stannous chloride in
10 ml concentrated HC1. Add 90 ml of distilled water
and 0.2 gm of KI. Mix well. Prepare fresh daily.
(d) Laboratory oven set to 100C.
Procedure
(a) Dilute the sample with 5 volumes of dimethylformamide .
(DMFl ~Burdick and Jackson, distilled in glass].
(b) Spo~ ~ TLC plate with 5 rnicrolit~rs of the sample and
5 microliters of a standard solution containing
cisplatin (and transplatinum and platinum B, if
appropriate) at a concentration approximately th~
same as that expected in the sample being analyzed.
Develop a height of 10 cm in a TLC tank pre-
equilibrated with the eluent. Spray the dried plate
with freshly prepared developer solution and place it
in a 100C oven fox 10 minutes. O~serve the yellow/
purple zones.
(c) Approximate Rf values:
0.65 - cisplatin
0~7~ - transplatinum
O.9 - platinum Bo
HPLC assays of the solutions of this invention
for cisplatin content may ~e conducted according to the
procedure described in our colleagues' published United
Kingdom Patent Application No. ~021946A. The preferred
mobile phase is ethyl acetate/methanol/dimethylformamide/
distilled water (~5/16/5/5). The standard preferably is
cisplatin dissolved in dimethylformamide at a concentration
of 1 mg/ml. Samples for analysis are diluted with
dimethylformamide to an approximate cisplatin concentration
of 1 mg/ml.
-14-
Although no particular advantage is obtained by
their presence, tbe solutions of this invention may, i~
desired, contain a customary, physiologically acceptable
excipient such as mannitol.
Based on stability studies to date, the pre
dicted stability of the solutions of this invention
(defined as a 10% loss of potency) i5 in excess of two
years at room temperature.
In a preferred embodiment of this invention~
the solutions are sterile and pyrogen-free, and are
packaged in sterile, pyrogen-free containers. Such
~olutions may then be diluted with, for example, Sterile
Water for Injection~ U.g.P., or Sterile Normal Saline
Solution, U.S.P., and administered by the intramuscular
or intravenous route. Means for sterilizing these
solutions are well known in the art. W8 prefer to pass
the solutions through a ~teril~, pyrogen-free 0.22 micron
Millipore filter, using aseptic techniques, under sterile
nitrogen pressure. Millipore is a registered trademark
of the Millipore Corporation for membrane filters~ The
sterile iltrate is collected in sterile, pyrogen-free
containers and is ultimately filled, in the desired
amount, into suitable sterile, pyrogen-free vials,
stoppered with sterile, pyrogen-free stoppers (preferably
teflon coated) and sealed with sterile aluminum seals.
For u~e in the treatment of cancer, the concen-
trated solutions are diluted to the desired concentration
~typically 1 mg ci~platin per ml) with, for example,
Sterile Water for Injection, U.S~P~, 5terile Normal Saline
Solution, U.S.P., or Sterile Glucose Solution and used by
intramuscular or LntraVenOUs injection, or intravenous
,.
-15-
infusion as known for prior art cispla~in preparationsO
Currently used dosages with mild to moderately acceptable
toxicity are in the range of 60-100 mg/M2 intravenously
as a single dose or divided over 3-5 days, to be
repeated at 4-week intervals. A dosage of 60 mg/M2 is
roughly equal to 1.5 mg/kg which in turn is roughly
equal ~o 105 mg~patient weighing 70 ky. Frequently,
use is made of concurrent therapy with other chemothera-
peutic agents for best results.
As used herein and in the claims, references
to "equivalents" of chloride ion per "equivalent" of
cisplatin means molar equivalents. Thus, for example,
when utilizing the preferred range of f~om about 3 to
about 7 equivalents of chloride ion per equivalent of
cisplatin, one would utilize from about 3 to about 7
moles of NaCl per mole of cisplatin but from about 1. 5
to about 3 . 5 moles of CaC12 per mole of cisplatin, etc.
Platinum B is an arbitrary designation used
herein for an a~id reaction product of cisplatin which
is one-half of the known Magnus red complex and has been
tentatively assigned the following structure:
rH4 ~ Cl C1~3
\ Pt /
H3N / \ Cl
This invention is illustrated by, but i~ in no
way l~mited to, the following Examples.
Example 1
Stable Concentrated Solution of Ci~platin ~lO mg/ml~ in
90% Polyethylene Glycol 400 - 10% lN HCl
Cisplatin (500 mg) was slurried in a solution o~
5 ml of lN HCl and 45 ml of Polyethylene Glycol 400.
After 2.5 days of stirring at room temperature (with the
container protected from light with aluminum foil) a clear
yellow solution was obtained. Aliquots of the solution
were placed in 17 ml amber vials, stoppered with teflon
coated stoppers, sealed with aluminum caps and placed on
storage stability tests at various temperatures. After
two weeks' storage at 45~C, thin layer chromatography
(TLC) indicated the presence of a txace of transplatinum
and approximately 1~ platinum B. Aftsr two weeks' storage
at 56C, TLC indicated the presence of <1% transplatinum
and approximately 3% platinum B. Samples stored for two
weeks at 56C were diluted with 4, 9 and 19 volumes of
water to give clear solutions containing 2, 1 and 0. 5
mg/ml, respectively, of cisplatinl A slight cloudiness
developed in each of the diluted samples after standing
approximately 18 hours at room temperature.
~ 7
Example 2
Stable Concentrated Solution of Cis~latin (10 m~/ml3 in
90% Pol~ethylene Glycol 400 - 10~ 0.5N HCl
Five ml of purified water U~S.P. and 5.0 ml of
lN Hcl were mixed and 90.0 ml of Polyethylene Gly~ol 400
was added. To 50 ml of the above solution was added 500
mg of cisplatin and the mixture was protected from light
with aluminum foil and stirred at room temperature for
24 hours to produce a clear solu~ion. TLC of the freshly
prepared solution showed only a cisplatin zone with a
possible trace of transplatinum. ~o ml aliquots o~ the
solution were placed in 17 ml amber vials~ stoppered with
teflon coated stoppers, sealed with aluminum caps and
placed on storage stability tests at various temperatures.
One sample vial was frozen in a dry ice-acetone bath for
one hour and then allowed to come to room temperature. A
clear solution was obta~ned, with no evidence o a pre-
cipitate. After three months' storage at both 37C and
45C, TLC indicated the presence of 1-2% platinum B and
a possible trace of transplatinum. After one month
storage at 56~C, TLC indicated the presence of more than
5~ but less than 10% of platinum B and a trace of trans-
platinum. Samples stored at 37C and 45C for three
months and at 56C for one month were diluted with four
volumes of purified water U.S~P. to give clear solutions
containing 2 mg/ml of cisplatin. The diluted solutions
remained clear after standing 24 hours at room temperature.
.
Stable Concentrated Solution of Cisplatin (lO m~/ml) Plus
CaCl2 (20 mg/ml) in 90% Polyethylene Glycol 400 - 10% 0.5N
HCl
~ wo gms of reagen~ grade anhydrous CaCl~ wa~
dissolved in a mixture o~ 5 ml purified water U.S.P. and
5 ml lN HCl. Polyethylene Glycol 400 (89 ml) was added to
bring the volume to lO0 ml, To 50 ml of this solution was
added 550 mg of cisplatin, and the mixture was protected
from light with aluminum foil and stirred at room temper
ature for 24 hours to give a clear solution. T~C o t~e
freshly prepared solution indicated only a cisplatin zone
with a possible trace of transplatinum. Two ml aliquots
of the solution were placed in 17 ml amber vials, stoppered
with teflon coated stoppers, sealed with aluminum caps and
placed on storage stability tests at various t~mperatures~
One sample vial was placed in a dry ice-acetone bath for
0.5 hour and froze to a clear gel. It was then allowed
to come to room temperature and a clear solution was ob
tained. After three months' storage at 37C, TLC indi-
cated the presence of 1~2% platinum B and a possible trace
of transplatinum. After three months' storage at 45C,
TLC indicated the presence of approximately 5~ platinum B
and a possible trace of transplatinum. After Qne month
storage at 56C, TLC indicated the presence of 8-10%
platinum B and a trace of transplatinum. Samples stored
at 37C and 45C for three months and at 56C for one
month were diluted with four volumes of purified water
U.S.P. to give clear solutions containing 2 mg/ml of
cisplatinO The diluted solutions remained clear after
standing 24 hours at room temperature.
.. . . .
.
t~
-19-
Example 4
Stable oncentrated Solution of Cisplatin (A~roxLmatel~
22 mg/ml) Plus CaCl~ (25 mg/ml) in 90% Polyethylene Glycol -
10% 0.5N ~Cl
To three ml of a solution of 90~ Polyethylene
Glycol 400 and 10~ 0.5N HCl was added 45 mg of cisplatin,
and the mixture was stirred for about one hour at room
temperature to o~tain a clear solution. An additional
30 mg of cisplatin was added (to~al of 25 mg/ml) and the
mixture was stirred at about 45C for one hour and then
at room temperature for 18 hours to produce a nearly
complete solution. The small amount of insolubl~ material
was removed by filtration. TLC of the filtrate showed
only a cisplatin zone with a possible trace of trans-
platinum. The remainder Gf the filtrate was placed in a
17 ml am~er vial, stoppered with a teflon coated stopper,
se~led with an aluminum cap and held at 45C for three
months~ After aging three months at 45C, TLC indicated
the presence of 1-2~ platinum B and no transplatinumO
Dilution of the aged solution with purified wate~ U.S.P.
to a concentration of 2 mg/ml of cisplatin gave clear
solutions, which remained ~lear after standing at room
temperature for 24 hours.
Example S
Stable Concentrated Solution of Cis latin (12 mq/ml) Plus
_ P ~
NaCl (10 m~/ml) in 9o~ Polyethylene Glycol 400 - 10~ 0.5N.
H
Sodium chloride (100 m~) was dissolved in
a solution of 5 ml purified water U~S~P~ and 5 ml lN
~.3.~7~3;
-20-
HCl. To this solution was added 90 ml of Polyethylene
Glycol 400 and the mixture was stirred for 15 minutes.
To 50 ml of the latter solution was added 500 mg of
cisplatin, and the mixture was stirred in the ~ark at
room ~emperature for 3 days to produce a clear solution.
T~C o the freshly prepared solution showed only a
cisplatin spot. High performance liquid chromatography
(HPLC) assay of the freshly prepared solution showed it
to contain 12 mg of cisplatin per ml~ Aliquots were
sealed in 17 ml amber vials as described in Example 3
and put on storage stability tests at various ~emperatures.
After storage at 37~C for three months, TLC indicated
the presence of less than 1% platinum B and no trans-
platinum. After storage at 56C for one month, TLC
indicated the presence of 1~2% platinum B an~ no
transplatinum. Dilution of the aged samples with
purified water U.S.P. to a concentration of 2 mg/ml of
cisplatin gave clear solutions, whic~ remained clear
after standing at room temperature for 24 hours.
HPLC assays of samples stored 3 months at
45C, 6 months at 37C and 8 months at room temperature
showed potency losses of 6.6%, 6.1~ and 2. 3%, respecti~ely.
. .. . .. . . .
Example 6
Stable Concentrated Solution of Clsplatin (11.4 mg/ml Plus
NaCl (10 mg/ml) n 90% Polyethylene Glycol 400 - 10% Water
To a solution of 50 mg NaCl in 5 ml of purified
water U.S.P. and 45 ml Polyethylene Glycol ~09 was added
500 mg of cisplatin; and the mixture was stirred in the
dark at room temperature ~or 6 hours to give a elear
solution. TLC of the freshly prepared solution showed
. .
r7 91
~ 2:L ~
only a cisplatin spot; HPLC assay showed it to contain
11.4 mg of cisplatin per ml. Aliquots were sealed in 17
ml amber vials as described in Example 3 and put on
storage stability tests at various temperatures. After
storage at 37C and 45C for 3 monthst TLC indicated the
presence of 1% platinum B and no transplatinum. After
storage at 56C for one month, TLC indicated the presence
of 2-3% platinum B and no transplatinum~ Dilution of the
aged samples with purified water U.S.P. to a concentration
of 2 mg~ml of cisplatin gave clear solutions, which
remained clear after standing at room temperature for 24 hours.
HPLC assays of samples stored 3 months at 45C,
6 months at 37C and 7 months at room temperature showed
potency losses of 6.1%, 7.8% and 0O9%~ respectively.
. . .
ExamEIle 7
Stable Concentrated Solution of Cis~latin (lO mg/ml) in
90% Polyethylene Glycol 600 - 10% 0.5N HCl
To a solution of 2.5 ml of purified water U7SoP~
2.5 ml of lN HCl and 45 ml of Polyethylene Glycol 600 was
added 500 mg of cisplatin, and the mixture was stirred in
the dark at room temperatuxe for S hours to obtaLn a clear
solution. TLC of the freshly prepared solution showed
only a cisplatin spot. Samples of the freshly prepared
solution were diluted with 1, 2, 3, 4, 5 and 9 volumes
o puriied~.~ater U.5.P.; these diluted solutions showed
no crystallization after standing for 16 hours at room
tèmperature or 4C. Aliquots of the freshly prepared
solution were sealed in 17 ml amber vials as described
in Example 3 and were put on storage stability tests at
various temperatures. After storage at 37C and 45C for
3 months, TLC indicated the presence of 1% platinum B
and no transplatinum. After storage at 56C for one
~ ~ ~ ?4,~?9
--22 -
month, TLC indicated the presence of 3.4% platinum B
and no transplatinum. Dilution of the aged samples with
purified water U~S.P. to ~ concentra~ion of 2 mg/ml of
cisplatin gave clear solutions, which remained clear
after standing at ro~m temperature for 24 hours.
Example 8
.
Stable Concentrated Solution of Cisplatin (10 m~ml)
Plus NaCl (lO ma/ml) in 90% PolvethYlene G1YCO1 k00 - 10%
.~ , _
0.2N HCl
To a solution of O.S gm NaCl in 4 ml of purified
water U.SOP., l ml of lN ~Cl and 45 ml of Polyethylene
Glycol 400 was added 250 mg of cisplatin, and the mixture
was stirred in the dark at room temperature for 4 hours to
give a clear yellow solution. TLC of the freshly prepared
solution showed ~nly a cisplatin spot. Dilutions of the
freshly prepared solution with 1, 2, 3, 4, 5 and 9 volumes
of purified water gave clear solutions which remained clear
after standing at room temperature for 24 hours. The 1,
2, 3, 4 and 5 volume dilutions showed no crystallization
when held at ~C for 24 hours. Aliquots of the freshly
, , ...................... _ . . . . .
prepared solution were sealed in 17 ml ambPr vials as
described in Example 3 and were puk on storage stability
tests at various temperatures. After storage at 37C
for three months, TLC indicated the presence of 1%
platin~n B with a possible trace of transplatinum. After
storage at 45C for three months, TLC indicated the
presence of 5% platinum B with a possible trace o trans-
pla~inum. After storage at 56C for one month, TLC
indicated the presence of Z-3% platinum B and no trans-
platinum. Dilution of the aged samples with purified
water U.S.P. to a concentration o~ 2 mg/ml of cisplatin
gave clear solutions which remained clear after standing
~23
for 24 hours at room temperature,
Example 9
Stable Concentrated Solution of CisE~atin (2.5 m~ml),
NaCl ~9 m~/ml) and Mannitol (12.5 mg/ml) in Acidified
31% (w/v) A~ueous Polyeth~lene Gl~ol 6000
- Sodium chloride (0.9 gm), mannitol (1.25 gm~
and Polyethylene Glycol 6000 (31.3 ~m5~ were dissolved in
sufficient purified water U~S.P. to make 100 ml of
solution, and the solution was then acidified to pH 2.2
with 1 N HCl (0O7 ml~. Cisplatin (255 mg) was added and
the mixture was stirred in the dar~ for 3 days at room
temperature to obtain a clear solution. TLC of the freshly
prepared solution showed only a cisplatin zone. Aliquots
o~ the freshly prepared solution were sealed in 17 ml
amber vials as described in Example 3 and were put on
storage stability tests at 45C and 56C. After storage
for two months at 45C and 56C, TLC showed less than 1%
platinum B and no transplatinum. Dilutivn of the aged
samples with an equal volume of purified water U.S.P.
gave c1ear solutions which remained clear after standing
at room temperature for 24 hours.
Stable Concentrated Solution of Cisplatin (15.8 mq/ml)
Plus NaCl (10 mg~ml) in 90% A~ueous Polyethylene_Glycol 400
Polyethylene Glycol 400 ~90 ml) was dissolved in
a solution of 1.0 gm NaCl in 10 ml purified water U.S.P.
-24-
To 60 ml of the resulting solutio~ wa5 added 900 mg of
cisplatin, and the mixture was stirred in the dark for
five hours at room temperature to obtain a clear solutio~.
TLC of the freshly prepared solution showed only a
cisplatin zone; ~P~C assay showed it to contain 15 . ~ mg
of cisplatin per ml~ ~lu~ion of the ~reshly prepared
solution with four volumes of purified water U.S.P. gave
a clear solution which remained clear after standing at
room temperature for 24 hours. ~liquots of the freshly
prepared solution wRre sealed in 17 ml am~er vials as
described in Example 3 and put on storage stability tests
at various temperatures. A~ter two months' storage at
45C, TLC indicated 1.5% platinum B and no transplatinum.
Ater one month storage at 56C, TLC indicated 2~
platinum B and no transplatinum. The sample aged at
56C was diluted to a concentration of 2 mg/ml with sterile
water for injection and the sample aged at ~45C was diluted
to concentrations of 2.5 and 5.0 mg/ml of cisplatin with
sterile water for injection. They each formed clear
solutions which remained clear after standing at room
. .
~ temperatuxe for 24 hours.
~ PLC assays of samples stored 3 months at 45C,
6 months at 37C and 8 months at room temperature showed
potency losses o 7.6%, 7.6~ and %t resp~ctively.
Example_ll
Stable Concentrated Solution of Cisplatin (15 m /ml) Plus
_... . _g_
CaC12 (25 mg/ml) in 90% A~ueous Polyethylene Glycol 400
.
.,
-25-
To a solution o 2.5 gms of CaC12 in 10 ml of
purified water U.S.P. was added 90 ml of Polyethylene
Glycol 400, and the resulting solution was stirred for
ten minutes. To 50 ml of the above solution was added
750 mg of cisplatin and the mixture was stirred for 5
hours in the dark at room temperature to give a clear
solution. TLC of the freshly prepared solution showed
only a cisplatin zone. Dilutions of the freshly prepared
solution with 1, 2, 5 and 10 volumes, respectively, of
purified water U.S.P. gave clear solutions. Aliquots of
the freshly prepared solution were sealed in 17 ml amber
vials as described in Example 3 and put on storage
stability at 45C and 56C. Af~er two months' storage
at 45C, TLC indicated the presence of 1.5% platinum B
and no transplatinum. After one month storage at 56C,
TLC indicated the presence of 2.5-5~ platinum B and no
transplatinum. The sample aged at 56C was diluted to a
concentration of 2 mg/ml, and the sample aged at 45C
was diluted to concentrations of 2~5 and 5~0 mg/ml~ of
cisplatin with sterile water for injection. They formed
clear solutions which remained clear after standing at
room temperature for 24 hours.
Example 12
Sterile, Stable, Concentrated Solution of Cisplatin in
90% Polyethylene Glycol 400 - 10% 0.5 N HCl (La~el claim
.
is 15 mg/ml of cisplatin activity)
NOTE: Cisplatin is a possible carcinogen. Protective
clothing, gloves, masks, eyeglasse~ and head covering must
be worn during the entire procedure. A11 work are~s and
equipment must be thoroughly cleaned to avoid any future
contamination,
9!'7~
--26 - .
FORMU~A
- Per ml Per 10~0 ml
Cisplatin 0.0l5 gm(l) 0.150 gm
Sodium Chloride 0.015 gm 0.150 gm
0.SN Hydrochloric Acid(2) 0.10 ml 19 0 ml
Polye~hylene Gl~col 400
(SENTRY grade) qOs. to 1.0 ml q.s. to 10~0 ml
(1)
This weight of cisplatin assum~s a potency of 1000
mcg~mg. To determine the amount of cisplatin required
use the following formula:
1000 x 0.015 ~m ~ = Grams of cisp}atin required
Potency of cisplatin in mcg/mg
~2)One liter of 0.SN hydrochloric acid is prepared as
follows:
1. Place 957~25 ml of Sterile Water for
Injection, U.S.P. in a clean one liter Erlenmeyer flask.
2. With rapid stirring, slowly and cautiously
add 42.75 ml of concentrated hydrochloric acid. Stir for
10 minutes. Stopper with a clean butyl rubber stopper.
MANUFACTURING INSTRUCTIONS FOR ONE LITER OF STERILE SOLUTION
1. Place 100 ml of 0.5 N hydrochloric acid in a clean,
calibrated l-liter Erlenmeyer fla~k containing a suitable
stirrer, such as a 6 cm magnetic, teflon coated stirrer
bar.
2. Add, with modera~e stirring, 15.0 grams of sodium
chloride. Stir until the salt is completely dissolved.
3. Add with rapid stirring 750 ml of Polyethylene ~lycol
~ ~ ' f.~. ~
27O
400 (SENTR~ grade) and stir for 5 minu~e$.
4. Remove the magnetic stirrer bar and drain excess fluid
back into the f la~k.
5. Cautiously add 15.0 grams of ~isplati~ activity.
6. Add Polyethylene Glycol 400 (SENTRY grade) to the 1
liter mark (a total of 880 ml of Polyethylene Glycol 400
required).
7. Place the teflon s~irrer har ~ack into the mixture and
stopper with a clean butyl rubber stoppe~
8. Wrap the flask in ~luminum foil to exclude all light.
9~ Rapidly stir ~or 24-48 hours at amhient room temperatur~.
A clear solution should be obtained. If a clear solution
is not obtained i~ 48 hours, the mixture may be wanmed to
37-40C for 2-6 hours in the absence of aîr and light ~o
`facilitate rapid solution of th~ remaining cisplatin~
Cool ~o 23-~7C.
10. Using aseptic te~hniquet pass the dark yellow solution
under proper sterile nitrogen pressure, through a suitabl~
;` sterile, pyrogen-free 0.22 micron Millipore filter~ Collect
the sterile filtrate in a sterile, pyxogen-free Erlenmey~r
flask. Stopper with a sterile, pyrogen-free butyl ruh~er
stopper. The solution may be stored in the dark.
11. Fill the required amount of sterile solution into
sterile, pyrogen-free amber ~ial~. Stopper with sterile,
pyrogen-free teflon stopper~ Seal with sterile aluminum
seals.
*
f~, Trademark
~ 2~
-28-
12. The vials should contain the following precautionary
label:
NOT FOR DIRECT INTRAMUSCULAR OR INTRAVENOUS USE*
The PEG-400 solution may be diluted with 14
parts of Sterile Water for Injection, U.S.P.
or Sterile Normal Saline Solution, U.S.P. to
give a 1 mg/ml solution of cisplatin. If
higher concentrations are required, proportionally
less Sterile Water or Saline Solution may be
used. The diluted solu~ions may be used intra-
venously and are stable at room ambient temper-
akure (22-26C) for at least 48 hours. Do not
refrigerate diluted solu~ions as crystals may
form.
13. Store the vials in the dark~
Example 13
Stable Concentrated Solution of Cisplatin (2. 5 mg/ml),
NaCl (9 ms/ml), CaC12 (15 mg~ml~ and Mannitol (10 mg/ml)
in Acldified 31% Aqueous Polyethylene Glycol 400
Sodium chloride (0.9 gm), CaC12 (1.5 gm) and
mannitol (1.0 gm) were dissolved in a mixture of 31. 25 ml
Polyethylene Glycol 400 and 40 ml purified water U.S.P~
The solution was acidified to p~ 2.2 with lN HCl (0.4 ml),
255 mg of cisplatin was added, the volume was brought to
100 ml with purified water U~S.P., and the mixture was
stirred,in the darX for 5 hours at room temperature to
obtain a clear solution. TLC o the ~reshly prepared
solution showed only A clsplatin zone.
~ 79
_~9 _
Example 14
The general pro~edure of Example 5 is repeated
except that the sodium chloride utilized therein i5 re-
placed by an equivalent amount of magnesium chloride, and
a stable concentrated solu~ion of cisplatin is thereby
produced.
Example 15
The general procedure of Example 5 i5 repeated
except that the sodium chloride utilized therei~ is re-
placed by an equivalent amount of triethylamine hydro-
chloride, and a stable concentratea solution of cisplatin
is produced.
Example 16
Th~ general procedure of Example 5 is repeated
except that the Polyethylene Glycol 400 utilized therein
is replaced ~y an equal volume of Polyethylene Glycols
200 and 300, respectiveIy, and stable concentrated
solutions o~ cisplatin are produced.
Example 17
The general procedure of Ex~mple 9 is repeated
except that ~he Polyethylene Glycol 6000 utilized therein
is replaced by an equal weight of Polyethylene Glycols
1000 and 4000, respectively, and stable concentrated
solutions of cisplatin are produced.
