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`
`69’ National
`l Formulary
` rmacopeia
`
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`
`
`
`\1 \
`
`LIES. Pha
`
`\
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`
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`
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`AMGEN INC.
`
`Exhibit 1015
`
`Ex. 1015 - Page 1 of 25
`
`Ex. 1015 - Page 1 of 25
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`AMGEN INC.
`Exhibit 1015
`
`

`

`
`
`
`
`LIJS. Phar
`
`
`
`
`
`
`
`69’ National
`'
`macopeza
`
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`Ex. 1015 - Page 2 of 25
`
`Ex. 1015 - Page 2 of 25
`
`

`

`
`
`2000
`
`THE UNITED STATES PHARMACOPEIA
`US P 24
`
`NF 19
`THE NATIONAL FORMULARY
`
`
`
`By authority of the United States Pharmacopeial
`Convention, Inc., meeting at Washington, D. C.,
`March 9—12, 1995. Prepared by the Committee of
`Revision and published by the Board of Trustees
`
`Ofi‘ieial from January 1, 2000
`
`UNITED STATES PHARMACOPEIAL CONVENTION, INC.
`
`12601 Twinbrook Parkway, Rockville, MD 20852
`
`Ex. 1015 - Page 3 of 25
`
`
`
`r—r
`
`Ex. 1015 - Page 3 of 25
`
`

`

`
`
`
`The inclusion in the Phannaéopeia or in the National Formulary of a monograph on any drug in
`respect to which patent or trademark rights may exist shall not be deemed, and is not intended
`as, a grant of, or authority to exercise, any right or privilege protected by such patent or
`trademark. All such rights and privileges are vested in the patent or trademark owner, and no
`other person may exercise the same without express permission, authority, or license secured
`from such patent or trademark owner.
`
`NOTICE AND WARNING
`
`Concerning U.S. Patent or Trademark Rights
`
`Concerning Use of USP or NF Text
`Attention is called to the fact that USP and NF text is fully copyrighted. Authors and others
`wishing to use portions of the text should request permission to do so from the Secretary of the
`USPC Board of Trustees.
`
`The United States Pharmacopeial Convention, Inc.
`© 1999
`12601 Twinbrook Parkway, Rockville, MD 20852.
`All rights reserved
`ISSN 0195-7996
`ISBN 1-889788-03-1
`
`Printed by National Publishing, Philadelphia, PA
`
`Ex. 1015 - Page 4 of 25
`
`Ex. 1015 - Page 4 of 25
`
`

`

`USP 24
`
`Physical Tests / (788) Particulate Matter in Injections
`
`1971
`
`(788) PARTICULATE MATTER
`IN INJECTIONS
`’
`
`*
`
`Particulate matter consists of mobile, randomly—Seurced, extra—
`neous substances, other than gas bubbles, that cannot be quantitated
`by chemical analysis due to the small amount of material that it
`represents and to its heterogeneous compOsition.
`Injectable solu-
`tions, including solutions constituted from sterile solids intended
`for parenteral use, should be essentially free from particles that can
`be observed on visual inspection. The tests described herein are
`physical tests performed for the purpose of enumerating subvisible
`extraneous particles within specific size ranges.
`Microscopic and light obscuration procedures for the determi-
`nation of particulate matter are given herein.
`It is expected that
`most articles will meet the requirements on the basis of the light
`obscuration test alone; however, it may be necessary to test some
`articles by the light obscuration test followed by the microscopic
`test to reach a conclusion on conformance to requirements.
`All large-volume injections for single-dose infusion and those
`small—volume injections for which the monographs specify such re-
`quirements are subject to the particulate matter limits set forth for
`the test being applied, unless otherwise specified in the individual
`monograph.
`Not all injection formulations can be examined for particles by
`one or both of these tests. Any product that is not a pure solution
`having a clarity and a viscosity approximating those of water may
`provide erroneous data when analyzed by the light obscuration
`counting method. Such materials may be analyzed by the micro—
`scopic method. Emulsions, colloids, and liposomal preparations are
`examples. Refer to the specific monographs when a question of test
`applicability occurs. Higher limits are appropriate for certain arti-
`cles and are specified in the individual monographs.
`In some instances, the viscosity of a material to be tested may
`be sufficiently high so as to preclude its analysis by either test
`method.
`In this event, a quantitative dilution with an appropriate
`diluent may be made to decrease viscosity, as necessary, to allow
`the analysis to be performed.
`‘
`_
`In the tests described below for large—volume and small-volume
`injections, the results obtained in examining a discrete unit or group
`of units for particulate matter cannot be extrapolated with certainty
`to other units that remain untested. Thus, statistically sound sam-
`pling plans based upon known operational factors must be devel-
`oped if valid inferences are to be drawn from observed data to
`characterize the level of particulate matter in a large group of units.
`Sampling plans should be based on consideration of product vol-
`ume, numbers of particles historically found to be present in com-
`parison to limits, particle size distribution of particles present, and
`variability of particle counts between units.
`
`LIGHT OBSCURATION PARTICLE COUNT
`TEST
`
`USP Reference Standards (1 l)——USP Particle Count RS.
`The test applies to large-volume injections labeled as containing
`more than 100 mL, unless otherwise Specified in the individual
`monograph.
`It counts suspended particles that are solid or liquid.
`This test applies also to single-dose or multiple-dose small-volume
`injections labeled as containing 100 mL or less that are either in
`solution or in solution constituted from sterile solids, where a test
`for particulate matter is specified in the individual monograph. In-
`jections packaged in prefilled syringes and cartridges are exempt
`from these requirements, as are products for which the individual
`monograph specifies that the label states that the product is to be
`used with a final filter.
`
`Test Apparatus
`
`The apparatus is an electronic, liquid-borne particle counting sys—
`tem that uses a light-obscuration sensor with a suitable sample-
`feeding device. A variety of suitable devices of this type are com-
`mercially available.
`It is the responsibility of those performing the
`test to ensure that the operating parameters of the instrumentation
`are appropriate to the required accuracy and precision of the test
`
`result, and that adequate training is provided for those responsible
`for the technical performance of the test.
`It is important to note that for Pharmacopeial applicationsvthe
`ultimate goal is that the particle counter reproducibly size and count
`particles present in the injectable material under investigation. The
`instruments available range from systems where calibration and
`other components of standardization must be carried out by manual
`procedures to sophisticated systems incorporating hardware- or soft-
`ware-based functions for the standardization procedures. Thus, it
`is not possible to specify exact methods to be followed for stan-
`dardization of the instrument, and it is necessary to emphasize the
`required end result of a standardization procedure rather than a spe-
`cific method for obtaining this result. This section is intended to
`emphasize the criteria that must be met by a system rather than
`specific methods to be used in their determination.
`It is the res-
`ponsiblity of user to apply the various methods of standardization
`applicable to a specific instrument. Critical operational criteria con-
`sist of the following.
`‘
`»
`'
`'
`Sensor Concentration Limits—Use an instrument that has a con-
`centration limit (the maximum number of particles per mL) iden-
`tified by the manufacturer that is greater than the concentration of
`particles in the test specimen to be connted. The vendor-certified
`concentration limit for a sensortis specified as that count level at
`which coincidence counts due to simultaneous presence of two or
`more particles, in the sensor view volume comprise less than 10%
`of the counts collected for lO-um particles.
`Sensor Dynamic Range—The: dynamic range of the instrument
`used (range of sizes of particlesthat can'be accurately sized and
`counted) must include the smallest particle size to be enumerated
`in the test articles.
`
`Instrument Standardization
`
`The following discussion of instrument standardization empha-
`sizes performance criteria rather than specific methods for calibrat-
`ing or standardizing a‘given instrument system. This approach is
`particularly evident in the description of calibration, where allow-
`ance must be made for manual methods as well as those based on
`firmware, software, or the use of electronic testing instruments. Ap-
`propriate instrument qualification is essential to performance of the
`test according to requirements. Since different brands of instru-
`ments may be used in the test, the user is responsible for ensuring
`that the counter used is operated according to the manufacturer’s
`specific instructions; the principles to be followed to ensure that
`instruments operate within acceptable ranges are defined below.
`The following information for instrument standardization helps
`ensure that the sample volume accuracy, sample flow rate, particle
`size response curve, sensor resolution, and count accuracy are ap-
`propriate to performance of the test. Conduct these procedures at
`intervals of not more than six months.
`'
`.
`
`SAMPLE VOLUME ACCURACY
`
`Since the particle count from a sample aliquot varies directly with
`the volume of‘ fluid sampled, it is important that the sampling ac-
`curacy is known to be within a certain range. For a sample volume
`determination, determine the dead (tare) volume in the sample
`feeder with filtered distilled or deionized water that has been passed
`through a filter having a porosity of 1.2 am or finer. Transfer a
`volume of filtered distilled or deionized water that is greater than
`the sample volume to a container, and weigh. Withdraw through
`the sample feeding device a volume that is appropriate for the spe-
`cific sampler, and again weigh the container; Determine the sample
`volume by subtracting the tare volume from the combined sample
`plus tare volumes; Verify that the value obtained is within 5% of
`the appropriate sample volume for the test. Alternatively, the sam-
`ple volume may be determined using a suitable Class A graduated
`cylinder (see Volumetric Apparatus (31)).
`[NOTE—Instruments of
`this type require a variable tare volume.’ This is the 'amount of
`sample withdrawn prior to counting. This volume may be deter-
`mined for syringe-operated samplers by setting the sample volume
`to zero and initiating sampling, so that the only volume of solution
`drawn is the tare. Subtract the tare volume from the total volume
`of solution drawn in the sampling cycle to determine the sample
`volume]
`
`
`
`
`Ex. 1015 '- Page 5 of 25
`
`
`Ex. 1015 - Page 5 of 25
`
`

`

`1972
`
`(788)
`
`Particulate Matter in Injections / Physical Tests
`
`USP 24
`
`SAMPLE FLOW RATE ‘
`
`SENSOR RESOLUTION
`
`Verify that the flow rate is within the manufacturer’s specifi-
`cations for the sensor used. This may be accomplished by using a
`calibrated stop watch to measure the time required for the instru-
`ment to withdraw and count a specific sample volume (i. e., the time
`between beginning and ending of the count cycle as denoted by
`instrdment indicator lights or other means). Sensors may be oper-
`ated accurately over a range cf flow rates. Perform the Test Pro-
`cedure at the same flow rate as that selected for calibration of the
`instrument.
`
`CALIBRATION
`
`'Use one of the following methods.
`Manual Method—Calibrate the instrument with a minimum of
`three calibrators, each consisting of near-monosize polystyrene
`spheres having diameters of about 10, 15, and 25 turn, in an aqueous
`vehicle.*, The calibrator spheres must have a mean diameter of
`within 5% of the 10-, 15—, and 25—um nominal diameters and be
`standardized against materials traceable to NIST standard reference
`materials. The number of spheres counted must be within the sen-
`sor’s concentration limit.
`.Prepare suspensions of the calibrator
`spheres in water at a concentration of 1000 to 5000 particles per
`mL, determine the channel setting that corresponds to the highest
`count setting for the sphere distribution. This is determined by
`using the highest count threshold. setting to split the distribution
`into two bins containing equal numbers of counts, with the instru-
`ment set in the differential count mode (moving window half-count
`method). Use only the central portion of the distribution in this
`calculation to avoid including asymmetrical portions of the peak.
`The portion of the distribution, which must be divided equally, is
`the count window. The window is bounded by threshold settings
`that will define a threshold voltage window of +20% around the
`mean diameter of the test spheres. The window is intended to in-
`clude all single spheres, taking into account the standard deviation
`of the spheres and the sensor resolution, while excluding noise and
`aggregates of spheres. The value of 20%‘was chosen based on the
`worst-case sensor resolution of 10% and the worst-case standard
`deviation of the spheres of 10%. Since the thresholds are propor—
`tionalito the area of the spheres rather than the diameter, the lower
`and upper voltage settings are determined by the equations:
`
`VL = 0.64V,
`
`in which V,_ is the lower voltage setting and V is the voltage at the
`peak center, and
`
`VU = 1.44v,,
`
`in which VU is the upper voltage setting.
`Once the center peak thresholds are determined, use these thresh-
`olds for the standards to create a regression of log voltage versus
`log particle size, from which the instrument settings for the 10- and
`25-um sizes can be determined.
`Automated Method—The calibration (size response) curve may
`be determined for the instrument-sensor system by the use of val-
`idated software routines offered by instrument vendors; these may
`be included as part of the instrument software or used in conjunc-
`tion with a microcomputer interfaced to the counter. The use of
`these automated methods is appropriate if the vendor supplies writ—
`ten certification that the software provides a response curve equiv-
`alent to that attained by the manual method and if the automated
`calibrationrs validated as necessary by the user.
`Electronic Method—Using a multichannel peak height analyzer,
`determine the center channel of the particle counter pulse response
`for each standard suspension. This peak voltage setting becomes
`the threshold used fOr calculation of the voltage response curve for
`the instrument. The standard suspensions to be used for the cali—
`bration are run in. order, and median pulse voltages for each are
`determined. These thresholds are then used to generate the size
`response curve manually or via software routines. The thresholds
`determined from the multichannel analyzer data are then transferred
`to the counter to complete the calibration.
`If this procedure is used
`with a comparator—based instrument, the comparators of the counter
`must be adjusted accurately beforehand.
`
`The particle size resolution of the instrumental particle counter
`is dependent upon the sensor used and may vary with individual
`sensors of the same model. Determine the resolution of the particle
`counter for IO-um particles using the monosized IO—um calibrator
`spheres. The relative standard deviation of the size distribution of
`the standard particles uSed is not more than 5%. Acceptable meth-
`ods of determining particle size resolution are ‘(1) manual deter-
`mination of the amount of peak broadening due to instrument re-
`sponse; (2) using an electronic method of measuring and sorting
`particle sensor voltage output with a multichannel analyzer; and (3)
`automated methods.
`
`Manual Method—Adjust the particle counter to operate in the
`cumulative mode or total count mode. Refer to the calibration curve
`obtained earlier, and determine the threshold voltage for the 10—p.m
`monosize spheres. Adjust 3 channels of the counter to be used in
`the calibration procedure as follows:
`Channel I is set for 90% of the threshold voltage.
`Channel 2 is set for the threshold voltage.
`Channel 3 is set for 110% of the threshold voltage.
`Draw a sample through the sensor, observing the count in Channel
`2. When the particle count in that channel has reached approxi—
`mately 1000, stop counting, and observe the counts in Channels 1
`and 3. Check‘ to see if the Channel 1 count and the Channel 3
`count are 168 i 10% and 32 i 10%, respectively, of the count
`in Channel 2.
`If not, adjust Channel 1 and Channel 3 thresholds
`to meet these criteria. When these criteria have been satisfied, draw
`a sample of suspension through the counter until
`the counts in
`Channel 2 have reached approximately 10,000, or until an appro-
`priate volume (e. g., 10 mL) of the sphere suspension has been
`counted. Verify that Channel 1 and Channel 3 counts are 168+ 3%
`and 32+ 3%, respectively, of the count in Channel 2.
`Record the particle size for the thresholds just determined for
`Channels 1, 2, and 3. Subtract the particle size for Channel 2 from
`the size for Channel 3. Subtract the particle size for Channel
`1
`from the size for Channel 2. The values so determined are the
`observed standard deviations on the positive and negative side of
`the mean count for the 10-um standard. Calculate the percentage
`of resolution of the sensor by the formula:
`
`100 [WWW
`
`in which S, is the highest observed standard deviation determined
`for the sphere, S, is the supplier’s reported standard deviation for
`the spheres, and D is the diameter, in pm, of the spheres as specified
`by the supplier. The resolution is not more than 10%.
`Automated Method—Software is available for some counters
`that allows for the automated determination of sensor resolution.
`This software may be included in the instrument or used in con-
`junction with a microcomputer interfaced to the counter. The use
`of these automated methods is appropriate if the vendor supplies
`written certification that the software provides a resolution deter-
`mination equivalent to the manual method and if the automated
`resolution determination is validated as necessary by the user.
`Electronic Method—Record the voltage output distribution of
`the particle sensor, using a multichannel analyzer while sampling a
`suspension of the 10— um particle size standard. To determine res-
`olution, move the cursor of the multichannel analyzer up anddown
`the electric potential scale from the median pulse voltage to identify
`a channel on each side of the 10- um peak that has approximately
`61% of the counts observed in the center channel. Use of the
`counter size response curve to convert the mV values of these two
`channels to particle sizes provides the particle size at within 1 stan-
`dard deviation of the 10- um standard Use these values to calculate
`the resolution as described under Manual Method.
`
`PARTICLE COUNTING ACCURACY
`
`Determine the particle counting accuracy of the instrument, using
`Method 1 (for small—volume injections) or Method 2 (for large-
`volume injections).
`
`Ex. 1015:13age 6 of 25
`
`
`Ex. 1015 - Page 6 of 25
`
`

`

`Physical Tests / (788) Particulate Matter in Injections
`
`1973
`
`USP 24
`
`Method 1—
`
`Procedure—Prepare the suspension and blank using the USP
`Particle Count RS. With the instrument set to count in the cumu-
`lative (total) mode, collect counts at settings of not less than 10 um
`and not less than 15 um. Mix the blank by inverting 25 times
`within 10 seconds, and degas the mixture by sonicating (at 80 to
`120 watts) for about 30 seconds or by allowing to stand. Remove
`the closure from the container, and gently stir the contents by hand-
`swirling or by mechanical means, taking care not to introduce air
`bubbles or contamination. Stir continuously throughout the analy—
`sis. ‘Withdraw directly from the container three consecutive vol-
`umes of not less than 5 mL each, obtain the particle counts, and
`discard the data from the first portion.
`[NOTE—Complete the pro—
`cedure within five minutes] Repeatthe procedure, using the sus-
`pension in place of the blank. From the averages of the counts
`resulting from the analysis of the two portions of the suspension at
`not less than 10 um and from the analysis of the two portions of
`the blank at not less than 10 um, calculate the number of particles
`in each mL by the formula:
`"
`.
`
`(P: ‘ Pb)/V.
`
`-
`
`in which P, is the average particle count obtained from the suspen—
`sion, P,, is the average particle count obtained from the blank, and
`V is the average volume, in mL, of the 4 portions tested. Repeat
`the calculations, using the results obtained at the setting of not less
`than 15 um.
`Interpretation—The instrument meets the requirements for Par-
`ticle Counting Accuracy if the count obtained at not less than 10
`um and the ratio of the counts obtained at not less than 10 pm to
`those obtained at not less than 15 um‘conform to the values that
`accompany the USP Particle Count RS. If the instrument does not
`meet the requirements for Particle Counting Accuracy, recalibrate
`with the remaining suspension and blank. ,If the results of the sec-
`ond test are within the limits given above, the instrument meets the
`requirements of the test for Particle Counting Accuracy.
`If on the
`second attempt the system does not meet the requirements of the
`test, determine and correct the source of the failures, and retest the
`, instrument.
`Method 2—
`
`Procedure—Using standard calibrator spheres having a nominal
`diameter of 15 to 30 um, prepare a suspension containing between
`50 and 200 particles per mL. Degas the suspension by sonicating
`(at 80 to 120 watts) for about 30 seconds or by allowing to stand.
`Properly suspend the particles by stirring gently, and perform five
`counts on 5-mL volumes of the suspension, using the particle
`counter lO-um size threshold. Obtain the mean cumulative particle
`count per mL. Pipet a volume of this suspension containing 250
`to 500 particles into a filter funnel prepared as described for Fil-
`tration Apparatus under Microscopic Particle Count. After drying
`the membrane, count the total number of standard spheres collected
`on the membrane filter. This count should be within 20% of the
`mean instrumental count per mL fer the suspension.
`
`in filtered distilled or deionized water, using a hand-held pressure
`nozzle with final filter or other appropriate filtered water source,
`such as distilled or deionized water passed through a capsule filter.
`The filter used should have a porosity of 1.2 pm or finer.
`To collect blank counts, use a cleaned vessel of the type and
`volume representative of that to be used in the test. Place a 50—mL
`volume of filtered distilled or deionized water in the vessel, and
`agitate the sample in the cleaned glassware by inversion or swirling.
`Degas by sonicating (at 80 to 120 watts) for about 30 seconds or
`by allowing to stand. Swirl the vessel containing the water sample
`by hand or agitate by mechanical means to suspend particles. »With-
`draw and obtain the particle counts for three consecutive samples
`of not less than 5 mL each, disregarding the first count.
`If more
`than 10 particles of 10 um or greater size, or more than 2 particles
`of 25 am or greater size are observed in the combined 10-mL sam—
`ple, the environment is not suitable for particulate analysis:
`the
`filtered distilled or deionized water and glassware have not been
`properly prepared or the counter is generating spurious counts.
`In
`this case, repeat the preparatory steps until conditions of analysis
`are suitable for the test.
`'
`
`Test Procedure
`
`TEST PREPARATION
`
`Prepare the test specimens in the following sequence. Outside
`of the laminar enclosure, remove outer closures, sealing bands, and
`any loose or shedding paper labels. Rinse the exteriors of the con-
`tainers with filtered distilled or deionized water as directed under
`Test Environment. Protect the containers from environmental con—
`tamination until analyzed. Withdraw the contents of the containers
`under test in a manner least likely to generate particles that could
`enter the sample. Contents of containers with removable stoppers
`may be withdrawn directly by removing the closures. Sampling
`devices having a needle to penetrate the unit closure may also be
`employed. Products packaged in flexible plastic containers maybe
`sampled by cutting the medication or'administration port tube or a
`corner from the unit with a suitably cleaned razor blade or scissors.
`Dry or lyophilized products may be constituted either by remov-
`ing the closure to add diluent or by injecting diluent with a hypo-
`dermic syringe having a 1.2-p.m'or finer syringe filter. If test spec-
`imens are to be pooled, remove the closure and empty the contents
`into a clean container.
`
`The number of test specimens must be adequate to provide a .
`statistically sound assessment of whether abatch or other large
`group of units represented by the test specimens meets or exceeds
`the limits.
`If the volume in the container is less, test a solution
`pool of 10 or more units. Single small—volume injection units may
`be tested if the individual unit volUme is 25 mL or more. For large—
`volume injections,»single units are tested. For large-volume injec-
`tions or for small-volume injections where the individual unit vol-
`ume is 25 mL or more, fewer than 10 single units may be tested,
`based on the definition of an appropriate sampling plan.
`
`Test Environment
`
`PRODUCT DETERMINATION
`
`Perform the test in an environment that does not contribute any
`significant amount of particulate matter. Specimens must be
`cleaned to the extent that any level of extraneous particles added
`has a negligible effect on the outcome of the test. The test speci-
`men, glassware, closures, and other required equipment preferably
`are prepared in an environment protected by high-efficiency partic-
`ulate air (HEPA) filters. Nonshedding garments and powder—free
`gloves preferably are worn throughout the preparation of samples.
`Cleanse glassware, closures, and other required equipment, pref-
`erably by immersing and scrubbing in warm, nonionic detergent
`solution. Rinse in flowing tap water, and then rinse again in flowing
`filtered distilled or deionized water. Organic solvents may also be
`used to facilitate cleaning.
`[NOTE—These steps describe one way
`to clean equipment; alternatively, particulate-free equipment may
`be obtained from a suitable vendor.] Finally, rinse the equipment
`
`Depending upon the dosage form being tested, proceed as di—
`rected under the appropriate category below.
`Liquid Preparations—
`Where the volume in the container is less than 25 mL—Prepare
`the containers as directed under Test Preparation. Mix and suspend
`the particulate matter in each unit by inverting the unit 20 times.
`[NOTE—Because of the small volume of some products, itmay be
`necessary to agitate the solution more vigorously to suspend the
`particles properly.]
`In a cleaned container, open and combine the
`contents of 10 or more units to obtain a volume of not less than 20
`mL. Degas the pooled solution by sonicating for about 30 seconds
`or by allowing the solution to stand undisturbed until it is free from
`air bubbles. Gently stir the contents of the container by hand-swirl—
`ing or by mechanical means, taking care not to introduce air bubbles
`or contamination. Withdraw a minimum of three aliquots, each not
`
`Ex. 1015 - Page 7 of 25
`
`
`
`
`Ex. 1015 - Page 7 of 25
`
`

`

`1974
`
`(788) Particulate Matter in Injections /‘ Physical Tests
`
`USP 24
`
`less than 5 mL in volume, into the light obscuration counter sensor.
`Discard the data from the first portion.
`'
`.Where the volume in the container is 25 mL or. more—Prepare
`the containers as directed under Test Preparation. .Mix and suspend
`the particulate matter in each unit by inverting the unit 20 times.
`Degas the solution by sonicating for about 30 seconds or by allow-
`ing the solution to stand undisturbed until it is free from air bubbles.
`Remove the closure of the unit or effect entry by other means so
`that the counter probe can be inserted into the middle of the solu-
`‘tion. Gently stir the contents of the unit by hand-swirling or by
`mechanical means. Withdraw not less than three aliquots, each not
`less than 5 mL in volume, into the light obscuration counter sensor.
`Discard the data from the first portion.
`Dry or Lyophilized Preparations—Prepare the containers as di-
`rected under Test Preparation. Open each container, taking care
`not to contaminate the opening or cover. Constitute as directed
`under Test Preparation, using the specified volume of filtered water
`or an appropriate filtered diluent if water is not suitable. Replace
`the closure, and manually agitate the container sufficiently to ensure
`dissolution of the drug.
`[NOTE—For some dry or lyophilized prod—
`ucts, it may be necessary to let the units stand for a suitable interval,
`and then agitate again to effect complete dissolution] After the
`drug in the constituted sample is completely dissolved, mix and
`suspend the particulate matter present in each unit by inverting it
`20 times prior to analysis. Proceed as directed for the appropriate
`unit volume under Liquid- Preparations, and analyze by withdraw-
`ing a minimum of three aliquots, each not less than 5 mL in volume,
`into the light obscuration counter sensor. Discard the data from the
`first portion.
`Products Packaged with Dual Compartments Constructed to
`Hold the Drug Product and a Solvent in Separate Compart-
`ments—Prepare the units to be tested as directed‘under Test Prep-
`aration. Mix each unit as directed in the labeling, activating and
`agitating so as to ensure thorough mixing of the separate compo-
`nents and drug dissolution. Degas the units to be tested by soni-
`cating or by allowing the solution to stand undisturbed until it is
`free from any air bubbles. Proceed as directed for the appropriate
`unit volume under Liquid Preparations, and analyze by withdraw-
`ing a minimum of three aliquots, each not less than 5 mL in volume,
`into the light obscuration counter sensor. Discard the data from the
`first portion.
`‘
`Products Labeled “Pharmacy Bulk Package Not for Direct
`Infusion”—Proceed as directed for Liquid Preparations where. the
`volume is 25 mL or more. Calculate the test result on a portion
`that is equivalent to the maximum dose given in the labeling. For
`example, if the total bulk package volume is 100 mL and the max-
`imum dose volume is 10 mL, then the average light obscuration
`particle count per mL would be multiplied by 10 to obtain the test
`result based on the lO-mL maximum dose.
`[NOTE—For the'cal-
`culations of test results, consider this maximum dose portion to be
`the equivalent of the contents of one full container.]
`
`Calculations
`
`Injections)—Average the
`(Small-volume
`Pooled Samples
`counts from the two or more aliquot portions analyzed. Calculate
`the number of particles in each container by theformula:
`
`PV/Van,
`
`,
`
`in which P is the average particle count obtained from the portions
`analyzed, Vr is the volume of pooled sample, in mL, Va is the vol—
`ume, in mL, of each portion analyzed, and n is the number of
`containers pooled.
`‘
`'
`’
`*
`Individual Samples (Small-volume Injections)—~Average the
`counts obtained for the 5-mL or greater aliquot portions from each
`separate unit analyzed, and calculate the number of particles in each
`container by the formula:
`'
`
`PV/V.1:
`
`in which P is the average particle count obtained from the portions
`
`analyzed, V is the volume, in mL, of the tested unit, and V, is the
`volume, in mL, of each portion analyzed.
`Individual Unit Samples (Large-volume Injections)—Average
`the counts obtained for the two or more 5-mL_ aliquot portions taken
`from the solution unit. Calculate the number of particles in each
`mL of Injection taken by the formula:
`
`' P/V,
`
`in which P is the average particle ‘countfor an individual 5 mL or
`greater sample volume, and V is the volume, in mL, of the portion
`taken.
`For all types of product, if the tested material has been diluted
`to effect a decrease in viscosity, the dilution factor must be ac-
`counted for in the calculation of the final test result.
`
`Interpretation
`
`The injection meets the requirements of the, test if the average
`number of particles present in the units tested does not exceed the
`appropriate value listed in Table 1.
`If the average number of par-
`ticles exceeds the limit, test the article by the Microscopic Particle
`Count Test.
`
`Table 1. Light Obscuration Test Particle Count.
`210 pm
`225 um
`
`Small-volume
`Injections:
`Large-volume
`Injections:
`
`6000
`
`25
`
`600 per container
`.
`
`3 per mL
`
`MICROSCOPIC PARTICLE COUNT TEST
`
`The microscopic particulate matter test may be applied to both
`large—volume and small-volume injections. This test enumerates
`subvisible, essentially solid, particulate matter in these products on
`a per-volume or per-container basis, after collection on a micro-
`porous membrane filter. Some articles cannot be tested meaning-
`fully by light obscuration.
`In such cases, individual monographs
`specify only this microscopic assay. Solutions exempted from anal-
`ysis using the microscopic assay are identified on a monograph
`basis. Examples are solutio