[Federal Register Volume 59, Number 40 (Tuesday, March 1, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-4518]


[[Page Unknown]]

[Federal Register: March 1, 1994]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

21 CFR Part 450

[Docket No. 89N-0440]

 

Antibiotic Drugs; New Tests and Specifications for Doxorubicin 
Hydrochloride and its Dosage Forms

AGENCY: Food and Drug Administration, HHS.

ACTION: Final rule.

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SUMMARY: The Food and Drug Administration (FDA) is amending the 
antibiotic drug regulations by revising the accepted standards for 
doxorubicin hydrochloride bulk and its dosage forms to reflect advances 
in analytic chemistry and improvements in the manufacturing technology 
of this antibiotic drug. These actions are being taken at the request 
of a manufacturer and will provide better quality control of this 
product.

DATES: Effective March 1, 1994; written comments, notice of 
participation, and request for a hearing by March 31, 1994; data, 
information, and analyses to justify a hearing by May 2, 1994.

ADDRESSES: Submit written comments to the Dockets Management Branch 
(HFA-305), Food and Drug Administration, rm. 1-23, 12420 Parklawn Dr., 
Rockville, MD 20857.

FOR FURTHER INFORMATION CONTACT: Peter A. Dionne, Center for Drug 
Evaluation and Research (HFD-520), Food and Drug Administration, 5600 
Fishers Lane, Rockville, MD 20857, 301-443-0335.

SUPPLEMENTARY INFORMATION:

 I. Background

    In the Federal Register of May 3, 1990 (55 FR 18617), FDA proposed 
to amend the antibiotic drug regulations for doxorubicin hydrochloride 
bulk and its dosage forms to reflect the significant improvement in the 
extraction and chromatographic separation methods since the original 
promulgation of regulations for doxorubicin hydrochloride in 1976. This 
improvement in manufacturing technology and analytical testing 
methodology has resulted in the production of highly purified drug 
substances and finished dosage forms.
    Specifically, FDA proposed to amend the regulations for doxorubicin 
hydrochloride bulk to: (1) Revise the doxorubicin hydrochloride content 
limits from 900 to 1,100 micrograms per milligram (g/mg) on 
the anhydrous basis to 970 to 1,020 g/mg on the anhydrous and 
solvent-free basis; (2) revise the high-pressure liquid chromatography 
(HPLC) test currently specified for determining the content of 
doxorubicin hydrochloride; (3) revise the pH range limits from a range 
of 3.8 to 6.5 to a range of 4.0 to 5.5; (4) add a total solvent residue 
test with an upper limit of not more than 2.5 percent; (5) add a 
chromatographic purity test with a total impurity specification of not 
more than 3.0 percent; (6) delete the microbiological agar diffusion 
assay for determining microbiological activity; and (7) revise the 
solution used for the disposition of waste material from synthetic 
detergent to dilute sodium hypochlorite.
    FDA also proposed to amend the regulations for doxorubicin 
hydrochloride for injection to: (1) Revise the HPLC test currently 
specified for determining the content of doxorubicin hydrochloride; (2) 
revise the pH range limits from a range of 3.8 to 6.5 to a range of 4.5 
to 6.5; (3) add a provision to the product description permitting the 
product to contain methylparaben; (4) replace the pyrogen test with the 
U.S. Pharmacopeia (U.S.P.) Bacterial Endotoxin Test with an upper limit 
of not more than 2.2 U.S.P. endotoxin units/mg of doxorubicin 
hydrochloride; (5) delete the microbiological activity specification 
for the doxorubicin hydrochloride used in making the product; (6) 
delete the depressor substances test for the product and add the 
depressor substances specification for the doxorubicin hydrochloride 
used in making the product; and (7) revise the solution used for the 
disposition of waste material from synthetic detergent to dilute sodium 
hypochlorite.
    FDA also proposed to the amend the regulation for doxorubicin 
hydrochloride injection to: (1) Revise the HPLC test currently 
specified for determining the content of doxorubicin hydrochloride; (2) 
replace the pyrogen test with the U.S.P. Bacterial Endotoxin Test with 
an upper limit of not more than 2.2 U.S.P. endotoxin units/mg of 
doxorubicin hydrochloride; (3) delete the microbiological activity 
specification for the doxorubicin hydrochloride used in making the 
product; and (4) revise the solution used for the disposition of waste 
material from synthetic detergent to dilute sodium hypochlorite.
    Interested persons were given until July 2, 1990, to submit written 
comments on this proposal and until June 4, 1990, to submit requests 
for an informal conference. One comment was received from the 
manufacturer requesting the proposed changes. This comment involved the 
description of the preparation of the resolution test solution and the 
system suitability requirements for the new HPLC method. The 
manufacturer requested that the preparation method in U.S.P. XXII, 
supp. I, be used and that the system suitability requirements be those 
in U.S.P. XXII, supp. I.
    FDA believes that both the method in the proposal and the U.S.P. 
method of preparation for the resolution test solution give 
satisfactory production of doxorubicinone and, therefore, will present 
both methods in this final rule. FDA believes that the term ``asymmetry 
factor'' is the correct one because measurements are being made on both 
sides of the HPLC peak and not just the tailing side. This final rule 
will, therefore, use the term ``asymmetry factor'' and will not be the 
same as the U.S.P., which uses the term ``tailing factor.'' To be 
consistent with the U.S.P., however, this final rule will use limits of 
not less than 0.7 and not more than 1.2 instead of not less than 0.9 
and not more than 1.2 that were proposed. FDA also believes that column 
efficiency should be stated as absolute column efficiency (hr) and 
not as theoretical plates (n), because the number of theoretical plates 
varies with the length and particle size of the packing in the column. 
If the column is packed with 10-micrometer (m) particles and 
is 25 centimeters (cm) long, then a column efficiency of not greater 
than 10.0 is equivalent to 2,500 theoretical plates which is close to 
the 2,250 plates stated in the U.S.P. The efficiency of the column, 
which will be stated in the final rule as absolute column efficiency 
(hr), is satisfactory if it is not greater than 10.0, equivalent 
to 2,500 theoretical plates for a 25-cm column of 10-m 
particles. To be consistent with the U.S.P., the proposed resolution of 
not less than 8.0 between the peaks of doxorubicin and doxorubicinone 
has been changed in the final rule to not less than 5.5.

II. Environmental Impact

    The agency has determined under 21 CFR 25.24(c)(6) that this action 
is of a type that does not individually or cumulatively have a 
significant effect on the human environment. Therefore, neither an 
environmental assessment nor an environmental impact statement is 
required.

III. Economic Impact

    The agency has considered the economic impact of this final rule 
and has determined that it does not require a regulatory flexibility 
analysis, as defined in the Regulatory Flexibility Act (Pub. L. 96-
354). Specifically, the final rule would impose an insubstantial 
amendment to existing requirements and would refine existing technical 
provisions without imposing more stringent requirements. Accordingly, 
the agency certifies that this rulemaking will not have a significant 
economic impact on a substantial number of small entities.

IV. Submitting Comments and Filing Objections

    Any person who will be adversely affected by this regulation may 
file objections to it and request a hearing. Reasonable grounds for the 
hearing must be shown. Any person who decides to seek a hearing must 
file (1) on or before March 31, 1994, a written notice of participation 
and request for a hearing, and (2) on or before May 2, 1994, the data, 
information, and analyses on which the person relies to justify a 
hearing, as specified in 21 CFR 314.300. A request for a hearing may 
not rest upon mere allegations or denials, but must set forth specific 
facts showing that there is a genuine and substantial issue of fact 
that requires a hearing. If it conclusively appears from the face of 
the data, information, and factual analyses in the request for a 
hearing that no genuine and substantial issue of fact precludes the 
action taken by this order, or if a request for a hearing is not made 
in the required format or with the required analyses, the Commissioner 
of Food and Drugs will enter summary judgment against the person(s) who 
request(s) the hearing, making findings and conclusions and denying a 
hearing. All submissions must be filed in three copies, identified with 
the docket number appearing in the heading of this document and filed 
with the Dockets Management Branch (address above).
    The procedures and requirements governing this document, a notice 
of participation and request for a hearing, a submission of data, 
information, and analyses to justify a hearing, other comments, and 
grant or denial of a hearing are contained in 21 CFR 314.300.
    All submissions under this document, except for data and 
information prohibited from public disclosure under 21 U.S.C. 331(j) or 
18 U.S.C. 1905, may be seen in the Dockets Management Branch (address 
above) between 9 a.m. and 4 p.m., Monday through Friday.

List of Subjects in 21 CFR Part 450

    Antibiotics.
    Therefore, under the Federal Food, Drug, and Cosmetic Act and under 
authority delegated to the Commissioner of Food and Drugs, 21 CFR part 
450 is amended as follows:

PART 450--ANTITUMOR ANTIBIOTIC DRUGS

    1. The authority citation for 21 CFR part 450 continues to read as 
follows:

    Authority: Sec. 507 of the Federal Food, Drug, and Cosmetic Act 
(21 U.S.C. 357).
    2. Section 450.24 is amended by revising paragraphs (a)(1)(i), 
(a)(1)(ii), and (a)(1)(v); by adding new paragraph (a)(1)(viii); by 
revising paragraph (a)(3)(i), the last sentence in the introductory 
text of paragraph (b), paragraphs (b)(1) and (b)(2); and by adding new 
paragraph (b)(8) to read as follows:


Sec. 450.24  Doxorubicin hydrochloride.

    (a) * * *
    (1) * * *
    (i) Its doxorubicin hydrochloride content is not less than 970 
micrograms and not more than 1,020 micrograms of doxorubicin 
hydrochloride per milligram on the anhydrous and solvent free basis.
    (ii) Its total solvent residue (as acetone and alcohol) is not more 
than 2.5 percent.
* * * * *
    (v) The pH of an aqueous solution containing 5 milligrams per 
milliliter is not less than 4.0 and not more than 5.5.
* * * * *
    (viii) The total of any impurities detected by high-pressure liquid 
chromatography assay is not more than 3.0 percent.
* * * * *
    (3) * * *
    (i) Results of tests and assays on the batch for doxorubicin 
hydrochloride content, solvent residue, depressor substances, moisture, 
pH, crystallinity, identity, and total impurities.
* * * * *
    (b) * * * Dispose of all waste material by dilution with large 
volumes of dilute sodium hypochlorite (bleach) solution.
    (1) Doxorubicin hydrochloride content (high-performance liquid 
chromatography). Proceed as directed in Sec. 436.216 of this chapter, 
using ambient temperature, an ultraviolet detection system operating at 
a wavelength of 254 nanometers, a 4.6-millimeter X 25-centimeter column 
packed with microparticulate (5 to 10 micrometers in diameter) packing 
material, such as trimethylsilane chemically bonded to porous silica, a 
flow rate of not more than 2.0 milliliters per minute, and a known 
injection volume of between 10 and 20 microliters. Mobile phase, 
working standard and sample solutions, resolution test solution, system 
suitability requirements, and calculations are as follows:
    (i)  Mobile phase. Prepare a suitable mixture of water, 
acetonitrile, methanol, and phosphoric acid (540:290:170:2). Dissolve 1 
gram of sodium lauryl sulfate in 1,000 milliliters of this solution, 
adjust with 2N sodium hydroxide to a pH of 3.60.1. Filter 
through a suitable filter capable of removing particulate matter to 0.5 
micron in diameter. Degas the mobile phase just prior to its 
introduction into the chromatograph.
    (ii)  Preparation of working standard, sample, and resolution test 
solutions--(A) Working standard solution. Dissolve an accurately 
weighed quantity of doxorubicin hydrochloride working standard in 
mobile phase to obtain a solution having a known concentration of 0.1 
milligram of doxorubicin hydrochloride per milliliter.
    (B)  Sample solution. Transfer approximately 20 milligrams of 
sample, accurately weighed, to a 200-milliliter volumetric flask, add 
mobile phase to volume, and mix. This yields a solution containing 0.1 
milligram of doxorubicin hydrochloride per milliliter (estimated).
    (C)  Resolution test solution. Use either of the following 
preparation methods:
    (1) To 2 milliliters of a 1.0 milligram per milliliter solution of 
doxorubicin hydrochloride, add 20 microliters of 1N hydrochloric acid. 
Hold for 30 minutes at 95  deg.C in an oil bath.
    (2) Dissolve about 10 milligrams of doxorubicin hydrochloride in 5 
milliliters of water, add 5 milliliters of phosphoric acid, and allow 
to stand for about 30 minutes. Adjust with 2N sodium hydroxide (about 
37 milliliters) to a pH of 2.60.1, add 15 milliliters of 
acetonitrile and 10 milliliters of methanol, mix, and filter. (Note: 
Portions of this solution may be frozen until needed, then thawed and 
mixed before use.)
    (3) The procedures in paragraphs (b)(1)(ii)(C)(1) and 
(b)(1)(ii)(C)(2) of this section generate doxorubicinone, the aglycone 
of doxorubicin. Use this solution to determine the resolution 
requirement for the chromatographic system.
    (iii)  System suitability requirements--(A)  Asymmetry factor. The 
asymmetry factor (AS) for the doxorubicin peak measured at a point 
5 percent of the peak height is not less than 0.7 and not more than 
1.2.
    (B)  Efficiency of the column. The absolute column efficiency 
(hr) is satisfactory if it is not greater than 10.0, equivalent to 
2,500 theoretical plates for a 25-centimeter column of 10-micrometer 
particles.
    (C)  Resolution. The resolution (R) between the peaks of 
doxorubicin and doxorubicinone (generated in situ) is satisfactory if 
it is not less than 5.5.
    (D) Capacity factor. The capacity factor (k) for doxorubicin is 
satisfactory if it is in the range between 1.0 and 5.0.
    (E) Coefficient of variation. The coefficient of variation 
(relative standard of deviation in percent) of 5 replicate injections 
is satisfactory if it is not more than 1.0 percent. If the system 
suitability parameters have been met, then proceed as described in 
Sec. 436.216(b) of this chapter.
    (iv)  Calculations. Calculate the micrograms of doxorubicin 
hydrochloride per milligram of sample as follows:

                                                                        
                                                                        
                                                      AU X PS X 100     
  Micrograms of doxorubicin hydrochloride    =  ------------------------
              per milligram                        AS X CU X (100-m-X)  
                                                                        

where:
AU = Area of the doxorubicin hydrochloride peak in the 
chromatogram of the sample (at a retention time equal to that 
observed for the standard);
AS = Area of the doxorubicin hydrochloride peak in the 
chromatogram of the doxorubicin hydrochloride working standard;
PS = Doxorubicin hydrochloride activity in the doxorubicin 
hydrochloride working standard solution in micrograms per 
milliliter;
CU = Milligrams of the sample per milliliter of sample 
solution;
m = Percent moisture content of the sample; and
X = Percent solvent residue determined as directed in paragraph 
(b)(2) of this section.
    (2) Residue solvent (as acetone and alcohol)--(i) Standard 
preparation. Transfer to a 100-milliliter volumetric flask about 200 
milligrams of acetone, 300 milligrams of dehydrated alcohol, and 1,000 
milligrams of dioxane, each accurately weighed, and mix. Dilute with 
water to volume, and mix. Transfer 5.0 milliliters of the resulting 
solution to a 50-milliliter volumetric flask, dilute with water to 
volume, and mix. This solution contains about 0.2 milligram of acetone, 
0.3 milligram of alcohol, and 1 milligram of dioxane per milliliter.
    (ii)  Solvent. Transfer about 100 milligrams of dioxane, accurately 
weighed to a 100-milliliter volumetric flask, dilute with water to 
volume, and mix.
    (iii)  Test preparation. Dissolve about 200 milligrams of 
doxorubicin hydrochloride sample in 3.0 milliliters of solvent.
    (iv) Chromatographic system (see United States Pharmacopeia 
(U.S.P.) Chromatography (621)). The gas chromatograph is equipped with 
a flame-ionization detector and a 4-millimeter X 2-meter column packed 
with 8-percent liquid phase G16 (see U.S.P. Chromatographic Reagents--
Phases) on 100- to 120-mesh support S1AB (potassium hydroxide-washed) 
(see U.S.P. Chromatographic Reagents--Supports). The column is 
maintained at about 60  deg.C, and helium is used as the carrier gas. 
Adjust the column temperature and carrier gas flow rate so that dioxane 
elutes in about 6 minutes. Chromatograph the standard preparation, and 
record the peak responses as directed under procedure; the resolution 
(R) between adjacent peaks is not less than 2.0; the relative standard 
deviations of the ratios of the peak responses of the acetone and 
dioxane peaks and of the alcohol and dioxane peaks for replicate 
injections is not more than 4.0 percent; and the tailing factor for the 
alcohol peak is not more than 1.5.
    (v)  Procedure. (Note: Use peak areas where peak responses are 
indicated.) Separately inject equal volumes (about 1 microliter) of the 
standard preparation and the test preparation into the chromatograph, 
record the chromatograms, and measure the responses for the major 
peaks. The relative retention times are about 0.2 for acetone, 0.5 for 
alcohol, and 1.0 for dioxane. Calculate the percentage, by weight, of 
acetone and alcohol, respectively, in the sample as follows:
X = Percent acetone or alcohol = 100(CA/CD)(DU/
WU)(RU/RS)
where:
CA = Concentration of acetone or alcohol in the standard 
preparation in milligrams per milliliter;
CD = Concentration of dioxane in the standard preparation in 
milligrams per milliliter;
DU = Total quantity of dioxane in the test preparation, in 
milligrams;
WU = Quantity of doxorubicin hydrochloride taken to prepare the 
test preparation, in milligrams;
RU = Response ratio of the analyte peak (acetone or alcohol) to 
the dioxane peak obtained from the test preparation; and
RS = Response ratio of the analyte peak (acetone or alcohol) to 
the dioxane peak obtained from the standard preparation.
The total of acetone and alcohol is not greater than 2.5 percent. Use 
the result obtained to calculate the doxorubicin hydrochloride content 
of the sample on the solvent-free basis.
* * * * *
    (8) Chromatographic purity. Proceed as directed in paragraph (b)(1) 
of this section, except prepare the sample solution by dissolving the 
sample to be tested in mobile phase to obtain a solution containing 
approximately 0.5 milligram of doxorubicin hydrochloride per 
milliliter. Calculate the percentage of impurities as follows:

                                                                        
                                                                        
            Percent total impurities               =    (100 S)/(S + r) 
                                                                        

where:
S = The sum of the responses of the minor component peaks; and
r = The response of the major doxorubicin hydrochloride peak.
The total related impurities detected is not more than 2.0 percent.
    3. Section 450.224a is amended by revising paragraphs (a)(1), 
(a)(3)(i)(a), (a)(3)(i)(b), the last sentence in the introductory text 
of paragraph (b), paragraphs (b)(1) and (b)(3); and by removing and 
reserving paragraph (b)(4) to read as follows:


Sec. 450.224a   Doxorubicin hydrochloride for injection.

    (a)  Requirements for certification--(1)  Standards of identity, 
strength, quality, and purity. Doxorubicin hydrochloride for injection 
is a freeze-dried powder whose components are doxorubicin hydrochloride 
and lactose. It may also contain methylparaben. Its doxorubicin 
hydrochloride content is satisfactory if it is not less than 90 percent 
and not more than 115 percent of the number of milligrams of 
doxorubicin hydrochloride that it is represented to contain. It is 
sterile. It contains not more than 2.2 U.S.P. endotoxin units per 
milligram of doxorubicin hydrochloride. Its moisture content is not 
more than 4.0 percent. When reconstituted as directed in the labeling, 
its pH is not less than 4.5 and not more than 6.5. It passes the 
identity test. The doxorubicin hydrochloride used conforms to the 
standards prescribed by Sec. 450.24(a)(1).
* * * * *
    (3) * * *
    (i) * * *
    (a) The doxorubicin hydrochloride used in making the batch for 
doxorubicin hydrochloride content, residue solvents, depressor 
substances, moisture, pH, crystallinity, identity, and total related 
impurities.
    (b) The batch for doxorubicin hydrochloride content, sterility, 
bacterial endotoxins, moisture, pH, and identity.
* * * * *
    (b) * * * Dispose of all waste material by dilution with large 
volumes of sodium hypochlorite (bleach) solution.
    (1) Doxorubicin hydrochloride content (high-performance liquid 
chromatography). Proceed as directed in Sec. 450.24(b)(1), preparing 
the sample solution and calculating the doxorubicin hydrochloride 
content as follows:
    (i) Sample solution. Prepare the sample solution by rinsing the 
contents of the vial into an appropriate sized volumetric flask with 
sufficient mobile phase to obtain a concentration of 0.1 milligram of 
doxorubicin hydrochloride per milliliter (estimated).
    (ii) Calculations. Calculate the doxorubicin hydrochloride content 
per vial as follows:

                                                                        
                                                                        
                                                         AU X PS X d    
 Milligrams of doxorubicin hydrochloride per    =  ---------------------
                    vial                                 AS X 1,000     
                                                                        

where:
AU = Area of the doxorubicin hydrochloride peak in the 
chromatogram of the sample (at a retention time equal to that 
observed for the standard);
AS = Area of the doxorubicin hydrochloride peak in the 
chromatogram of the doxorubicin hydrochloride working standard;
PS = Doxorubicin hydrochloride activity in the doxorubicin 
hydrochloride working standard solution in micrograms per 
milliliter; and
d = Dilution factor of the sample.
* * * * *
    (3) Bacterial endotoxins. Proceed as directed in the United States 
Pharmacopeia (U.S.P.) Bacterial Endotoxin Test, using a solution of 
doxorubicin hydrochloride for injection containing 1.1 milligrams of 
doxorubicin hydrochloride per milliliter. The specimen under test 
contains not more than 2.2 U.S.P. endotoxin units per milligram of 
doxorubicin hydrochloride.
    (4) [Reserved]
* * * * *
    4. Section 450.224b is amended by revising paragraphs (a)(1), 
(a)(3)(i)(A), (a)(3)(i)(B), the last sentence in the introductory text 
of paragraph (b), and paragraph (b)(1); by removing and reserving 
paragraph (b)(2); and by revising paragraph (b)(4) to read as follows:


Sec. 450.224b   Doxorubicin hydrochloride injection.

    (a)  Requirements for certification--(1)  Standards of identity, 
strength, quality, and purity. Doxorubicin hydrochloride injection is 
an aqueous solution of doxorubicin hydrochloride in an isosmotic 
diluent. Each milliliter contains doxorubicin hydrochloride equivalent 
to 2 milligrams of doxorubicin hydrochloride. Its doxorubicin 
hydrochloride content is satisfactory if it is not less than 90 percent 
and not more than 115 percent of the number of milligrams it is 
represented to contain. It is sterile. It contains not more than 2.2 
U.S.P. endotoxin units per milligram of doxorubicin hydrochloride. Its 
pH is not less than 2.5 and not more than 3.5. It passes the identity 
test. The doxorubicin hydrochloride used conforms to the standards 
prescribed by Sec. 450.24(a)(1).
* * * * *
    (3) * * *
    (i) * * *
    (A) The doxorubicin hydrochloride used in making the batch for 
doxorubicin hydrochloride content, residue solvents, depressor 
substances, moisture, pH, crystallinity, identity, and total related 
impurities.
    (B) The batch for doxorubicin hydrochloride content, sterility, 
bacterial endotoxins, pH, and identity.
* * * * *
    (b) * * * Dispose of all waste material by dilution with large 
volumes of sodium hypochlorite (bleach) solution.
    (1)  Doxorubicin hydrochloride content (high-performance liquid 
chromatography). Proceed as directed in Sec. 450.24(b)(1), preparing 
the sample solution and calculating the doxorubicin hydrochloride 
content as follows:
    (i)  Sample solution. Dilute an accurately measured volume of 
sample equivalent to not less than 2 milligrams of doxorubicin 
hydrochloride, quantitatively with mobile phase to obtain a solution 
containing 0.1 milligram of doxorubicin hydrochloride per milliliter 
(estimated).
    (ii) Calculations. Calculate the milligrams of doxorubicin 
hydrochloride per milliliter of sample as follows:

                                                                        
                                                                        
                                                         AU X PS X d    
 Milligrams of doxorubicin hydrochloride per    =  ---------------------
                  milliliter                             AS X 1,000     
                                                                        

where:
AU = Area of the doxorubicin hydrochloride peak in the 
chromatogram of the sample (at a retention time equal to that 
observed for the standard);
AS = Area of the doxorubicin hydrochloride peak in the 
chromatogram of the doxorubicin hydrochloride working standard;
PS = Doxorubicin hydrochloride activity in the doxorubicin 
hydrochloride working standard solution in micrograms per 
milliliter; and
d = Dilution factor of the sample.
    (2) [Reserved]
* * * * *
    (4)  Bacterial endotoxins. Proceed as directed in the United States 
Pharmacopeia (U.S.P.) Bacterial Endotoxin Test, using a test solution 
prepared by diluting doxorubicin hydrochloride injection with sterile 
water for injection to obtain a concentration of 1.1 milligrams of 
doxorubicin hydrochloride per milliliter. The specimen under test 
contains not more than 2.2 U.S.P. endotoxin units per milligram of 
doxorubicin hydrochloride.
* * * * *

    Dated: February 18, 1994.
Albert Rothschild,
Acting Director, Office of Compliance, Center for Drug Evaluation and 
Research.
[FR Doc. 94-4518 Filed 2-28-94; 8:45 am]
BILLING CODE 4160-01-F