#234 
 
Guidance for Industry 
 
Question-Based Review for the Chemistry, 
Manufacturing, and Controls Technical Section 
Of Animal Drug Applications 
 
Submit comments on this guidance at any time.  Submit electronic comments to 
http://www.regulations.gov.  Submit written comments to the Division of Dockets Management 
(HFA-305), Food and Drug Administration, 5630 Fishers Lane, Room 1061, Rockville, MD 
20852.  All comments should be identified with the docket number FDA-2016-D-0620. 
 
For questions regarding this document, contact AskCVM@fda.hhs.gov. 
 
Additional copies of this guidance document may be requested from the Policy and Regulations 
Staff, Center for Veterinary Medicine (HFV-6), Food and Drug Administration, 7519 Standish 
Place, Rockville, MD 20855, and may be viewed on the Internet at 
http://www.fda.gov/AnimalVeterinary/default.htm or http://www.regulations.gov. 
 
 
 
 
U.S. Department of Health and Human Services 
Food and Drug Administration 
Center for Veterinary Medicine 
December 2016 
   
  Contains Nonbinding Recommendations 
TABLE OF CONTENTS 
 
 
I.  INTRODUCTION .............................................................................................................. 4 
II.  DRUG SUBSTANCE (2.3.S) QUESTIONS ...................................................................... 6 
2.3.S.1  General Information .............................................................................................. 6 
2.3.S.2  Manufacture .......................................................................................................... 7 
2.3.S.3  Characterization .................................................................................................... 9 
2.3.S.4  Control of Drug Substance .................................................................................. 10 
2.3.S.5  Reference Standards ............................................................................................ 12 
2.3.S.6  Container Closure System ................................................................................... 13 
2.3.S.7  Stability ............................................................................................................... 14 
III.  DRUG PRODUCT (2.3.P) QUESTIONS ...................................................................... 15 
2.3.P.1  Description and Composition .............................................................................. 15 
2.3.P.2  Pharmaceutical Development .............................................................................. 16 
2.3.P.2.1  Components of the Product ............................................................................. 16 
2.3.P.2.1.1 Drug Substance ........................................................................................... 16 
2.3.P.2.1.2 Excipients ................................................................................................... 17 
2.3.P.2.2  Drug Product ................................................................................................... 18 
2.3.P.2.3  Manufacturing Process Development ............................................................. 19 
2.3.P.2.4  Container Closure System ............................................................................... 21 
2.3.P.3  Manufacture ........................................................................................................ 21 
2.3.P.4  Control of Excipients .......................................................................................... 26 
USP Excipients .................................................................................................................. 26 
Non-USP Excipients.......................................................................................................... 27 
Excipients from Animal Origin ......................................................................................... 27 
Novel Excipients................................................................................................................ 28 
2.3.P.5  Control of Drug Product ...................................................................................... 28 
2.3.P.6  Reference Standards and Materials ..................................................................... 30 
2.3.P.7  Container Closure System ................................................................................... 31 
2.3.P.8  Stability ............................................................................................................... 32 
IV.  STERILE PROCESS VALIDATION QUESTIONS:  ASEPTIC PROCESSING ...... 33 
Buildings and Facilities......................................................................................................... 33 
Process .................................................................................................................................. 33 
Filtration ................................................................................................................................ 34 
2  Contains Nonbinding Recommendations 
Process Simulations (also known as media fills) .................................................................. 36 
Steam-In-Place ...................................................................................................................... 37 
Component Preparation ........................................................................................................ 38 
Microbiological Monitoring of the Environment ................................................................. 39 
Process Control Documentation ........................................................................................... 40 
V.  STERILE PROCESS VALIDATION QUESTIONS:  TERMINAL MOIST STEAM 
STERILIZATION ..................................................................................................................... 41 
Description of the Process and Product ................................................................................ 41 
Thermal Qualification of the Cycle ...................................................................................... 43 
Microbiological Efficacy of the Cycle .................................................................................. 44 
Microbiological Monitoring of the Environment ................................................................. 45 
Process Control Documentation ........................................................................................... 45 
VI.  STERILE PROCESS VALIDATION QUESTIONS:  RADIATION STERILIZATION
  46 
Description of the Process and Product ................................................................................ 46 
Dose Mapping and Validation Studies ................................................................................. 48 
Microbiological Efficacy of the Cycle .................................................................................. 49 
Microbiological Monitoring of the Environment ................................................................. 50 
Process Control Documentation ........................................................................................... 50 
VII.  STERILE PROCESS VALIDATION QUESTIONS:  MICROBIOLOGICAL 
TESTING CONTROLS AND STABILITY CONSIDERATIONS ......................................... 51 
Container-Closure Integrity .................................................................................................. 51 
Preservative Effectiveness .................................................................................................... 52 
Pyrogen or Endotoxin Testing .............................................................................................. 52 
Sterility Testing ..................................................................................................................... 53 
Microbiological Release and Stability Testing ..................................................................... 53 
ENDNOTES ............................................................................................................................. 54 
 
   
3  Contains Nonbinding Recommendations 
Guidance for Industry 
 
Question-Based Review for the Chemistry, 
Manufacturing, and Controls Technical Section 
Of Animal Drug Applications 
 
This guidance represents the current thinking of the Food and Drug Administration (FDA or 
Agency) on this topic.  It does not establish any rights for any person and is not binding on FDA 
or the public.  You can use an alternative approach if it satisfies the requirements of the 
applicable statutes and regulations.  To discuss an alternative approach, contact the FDA staff 
responsible for this guidance as listed on the title page. 
 
I.  INTRODUCTION 
 
Applicants must submit information on chemistry, manufacturing, and controls (CMC) to 
support the approval of new animal drug applications (NADAs) and abbreviated new animal 
drug applications (ANADAs) or the conditional approval of applications for conditional approval 
(CNADAs).1  The Center for Veterinary Medicine (CVM) reviews the CMC information for new 
animal drugs to ensure that applicants have methods and controls in place for manufacturing, 
processing, and packaging that are adequate for assuring and preserving the identity, strength, 
quality, and purity of the new animal drug and, in the case of a generic drug, to ensure that it is 
equivalent to the reference listed new animal drug (RLNAD).  In order to improve the process 
for submission and review of CMC information for animal drugs, CVM has developed a series of 
questions that focus on the critical scientific and regulatory issues and pharmaceutical attributes 
essential for ensuring the quality of new animal drug substances and products.  Termed 
Question-based Review (QbR), these questions provide a general framework for original CMC 
submissions to investigational new animal drug (INAD) files, generic investigational new animal 
drug (JINAD) files, NADAs, ANADAs, CNADAs, and veterinary master files (VMFs). 
 
QbR is organized according to the Common Technical Document - Quality (CTD-Q).2 i  
Applicants who elect to use the QbR format for their CMC submissions should provide summary 
information to address the QbR questions in the CTD-Q Module 2 Quality Overall Summary 
(QOS), with supporting documentation and data in Module 3.  QbR includes a number of high-
level questions (bolded and boxed) applicants should address when preparing the QOS.  Under 
each high-level question, there may be one or more detailed questions (bolded) focusing on 
specific information that applicants should provide as part of the response to the high-level 
question.  In addition, this guidance document provides CVMs current thinking (italicized) on 
how applicants may best address the QbR questions and addresses some questions commonly 
asked by applicants (underlined).  The schematic below illustrates the QbR formatting. 
 
                                                 
 
1 21 U.S.C. 360b(c)(2)(A)(i), 360b(d)(1)(C), and 360ccc(c)(1); 21 CFR 514.1(b)(4) and (5). 
2 All FDA guidances mentioned in this document are available at 
http://www.fda.gov/RegulatoryInformation/Guidances/default.htm. 
4  Contains Nonbinding Recommendations 
 
High-level question 
CVMs current thinking 
 
Detailed question 
CVMs current thinking 
 
Questions commonly asked by the applicant 
CVMs current thinking 
 
This guidance is divided into three sections.  Section II of this guidance contains the QbR 
questions that address Section 2.3.S of the CTD-Q, drug substance.  Section III of this guidance 
contains the QbR questions that address section 2.3.P of the CTD-Q, drug product.  Sections IV 
through VII of this guidance contain the QbR questions that address sterile processing 
information for sterile drug substances and drug products.  If you are a drug substance 
manufacturer, you should provide a response to each of the high-level questions included in 
Section II as part of your QOS.  If you are an applicant seeking approval of a drug product, you 
should provide a response to each of the high-level questions in both Section II and Section III as 
part of your QOS.3  If your drug substance or drug product is sterile, you should also provide a 
response to each of the high-level questions in Sections IV through VII that apply to your chosen 
method of sterilization (e.g., aseptic processing, gamma irradiation).  All applicants seeking 
approval of sterile drug products should answer the questions regarding microbiological methods 
and stability considerations in Section VII.  An applicant may reference a master file to respond 
to some of the high-level questions related to drug substance manufacturing and sterile process 
validation.  When a master file reference may be appropriate, it is noted under the question. 
 
CVMs eSubmitter templates for CMC technical section submissions ((J)INAD P) and original 
VMF submissions (Type II and V) also utilize the QbR format.  The questions in the eSubmitter 
templates are derived from the high-level and detailed questions in this guidance but may be 
modified to better accommodate the electronic submission process.  The applicant can find 
information equivalent to that provided in the QbR questions commonly asked by the 
applicant, as well as CVM's current thinking about how applicants may best address the QbR 
questions, in the helpful hint (lightbulb icon) for each question in the eSubmitter template. 
 
When an applicant submits a QOS that fully addresses the QbR, this helps to assure product 
quality and may reduce the number of CMC review cycles by enhancing the quality of 
submissions and reviews through the use of a standardized set of critical questions.  CVM 
reserves the right to request information or material or define conditions not specifically 
described in the QbR questions and this guidance document, in order to adequately assess 
the safety, effectiveness, and quality of the product. 
 
   
                                                 
 
3 The term drug product here refers to a pharmaceutical dosage form or Type A medicated article. 
5  Contains Nonbinding Recommendations 
In general, FDAs guidance documents do not establish legally enforceable responsibilities.  
Instead, guidances describe the Agencys current thinking on a topic and should be viewed only 
as recommendations, unless specific regulatory or statutory requirements are cited.  The use of 
the word should in Agency guidances means that something is suggested or recommended, but 
not required. 
 
II.  DRUG SUBSTANCE (2.3.S) QUESTIONS 
 
2.3.S.1  General Information 
The drug product applicant should provide information for all questions in this section in 
the drug product submission. 
 
What are the nomenclature, molecular structure, molecular formula, CAS number, 
and molecular weight? 
 
Properties include but are not limited to: 
Chemical Name: 
CAS #: 
USAN: 
Molecular Structure (including relative and absolute stereochemistry): 
Molecular Formula: 
Molecular Weight: 
 
What are the physicochemical properties? 
 
Properties include but are not limited to: 
Physical Description (appearance, color, physical state): 
pKa: 
Polymorphism (polymorph, solvate, hydrate, etc.): 
Solubility Characteristics (as function of pH): 
Hygroscopicity: 
Melting/Boiling Point: 
Partition Coefficient: 
Optical Rotation: 
 
Should all of these properties be reported, even if they are not critical? 
Report ALL physicochemical properties listed in the question even if they are not critical.  
If a property is not quantified, explain why, for example: 
  No pKa because there are no ionizable groups in the chemical structure; 
  No melting point because compound degrades on heating; or 
  No other polymorph observed during polymorphism screening. 
   
6  Contains Nonbinding Recommendations 
Reference to a Master File (MF) is acceptable for non-critical physicochemical proprieties, 
but critical physicochemical properties should be provided in the application or (J)INAD 
file.  Physicochemical information such as polymorphic form, pKa, solubility, or other 
properties critical to the successful development of a robust formulation and manufacturing 
process should be reported. 
 
Should solubility data be provided? 
The drug product applicant should include this information if the solubility is crucial to the 
successful development of a robust formulation and manufacturing process.  Aqueous 
solubility should be reported as a function of pH in tabular form.  Provide actual values for 
the solubility as well as descriptive phrases (such as slightly soluble) as defined in the 
current United States Pharmacopoeia (USP). 
 
Should pH-solubility profiles be provided for all known polymorphic forms? 
No; it is essential that the pH-solubility profile be provided for the form present in the drug 
product.  The relative solubility (at one pH) should be provided for any other more-stable 
form(s). 
 
The CDER/CBER GFI M4:  The CTD-Quality Questions and Answers/Location Issues ii 
states that only the polymorphic form used in the drug product should be described in S.1 
and other known polymorphic forms should be described in S.3.  Where does CVM want 
this information? 
This information may be included in either S.1 or in S.3.  Wherever presented, list all 
polymorphic forms reported in literature and provide brief discussion (i.e., which one is the 
most stable form) and indicate which form is used for this product. 
 
Other polymorph information should be presented by the drug product applicant as 
follows: 
  2.3.S.3 Characterization: Studies performed (if any) and methods used to identify the 
potential polymorphic forms of the drug substance (e.g., X-ray, DSC, and literature) 
  2.3.S.4 Specification: Justification of whether a polymorph specification is needed 
and the proposed analytical method 
  2.3.P.2.1.1 Pharmaceutical Development  Drug Substance: Studies conducted to 
evaluate if polymorphic form affects drug product properties 
 
Why does CVM need to know the physicochemical properties?  Why does the drug product 
applicant need to report these properties? 
Physical and chemical properties may affect the development, manufacture, or performance 
of the drug product. 
 
2.3.S.2  Manufacture 
The drug product applicant may reference an MF to address some questions in this section.  
See individual questions for details. 
 
7  Contains Nonbinding Recommendations 
Who manufactures the drug substance? 
 
Reference to an MF is acceptable with a Letter of Authorization and identification of the 
US Agent (if applicable).  Alternatively, provide the name, address, and responsibility of 
each manufacturer, including contractors, and each proposed production site or facility 
involved in manufacturing and testing.  Identify the US Agent (if applicable). 
 
What is the current FDA inspection status? 
 
Provide any known information regarding the Good Manufacturing Practices (GMP) status 
of the facility, including FDA Establishment Identifier (FEI) number, last inspection date, 
and outcome. 
 
What is the starting material(s)?  Provide justification. 
 
Reference to an MF is acceptable. 
 
How does CVM define starting material? 
CVM considers a regulatory starting material to be a well characterized, commercially 
available material that is also used outside the pharmaceutical industry, and that 
contributes to the final drug substances structure.  For more details, see CVM GFI #169: 
Drug Substance Chemistry, Manufacturing, and Controls Information,iii CDER/CBER 
GFI/ICH Q7:  Good Manufacturing Practice Guidance for Active Pharmaceutical 
Ingredients,iv and CDER/CBER GFI/ICH Q11:  Development and Manufacture of Drug 
Substances.v 
 
What are the manufacturing processes and controls and how do they ensure 
consistent production of the drug substance? 
 
Reference to an MF is acceptable.  Include the source of the material (i.e., synthetic or 
natural) when both sources are available.  The MF holders Certificate of Analysis (COA) 
for the batch(es) used to manufacture the drug product should be provided in the body of 
data 3.2.S.4.4. 
 
Alternatively, a complete and detailed description of the manufacturing process and 
controls used to produce the drug substance should be provided.  This includes a flow 
diagram, the batch size, specifications for raw materials, the controls performed at critical 
steps of the manufacturing process, tests and acceptance criteria for isolated and final 
intermediates, and a description and justification of allowable reprocessing. 
 
What should be included in the flow diagram? 
A flow diagram of the manufacturing process should include reagents, reaction conditions, 
and solvents as well as chemical structures of starting materials, intermediates, and the 
final drug substance. 
 
8  Contains Nonbinding Recommendations 
Where should specifications for raw materials be reported? 
The quality control testing of raw materials such as solvents, reagents, etc. should be 
included in Module 3. 
 
Can a different manufacturing process/facility be used for the pilot batches? 
Yes; a comparison of the manufacturing processes and equipment should be provided.  
Where there are significant differences, provide data to support the changes. 
 
Is the drug substance manufactured from, processed with, or does it otherwise contain 
material of animal origin? 
Provide a risk assessment of possible adventitious agent contamination for the material in 
question and identify any steps adopted to mitigate the risk.  For example, cattle derived 
material may be subject to prion contamination, among other things.  To mitigate this risk 
you could source non-specified risk materials.  A description or documentation Bovine 
Spongiform Encephalopathy / Transmissible Spongiform Encephalopathy (BSE/TSE 
certification) identifying the tissue source of the material, age of the animal, country of 
origin, etc. could be provided to substantiate that the sourced material is not a specified 
risk material and does not pose a significant risk to the recipient of the finished product. 
 
Are any additives used?  Provide justification. 
 
What are the filling procedures for the primary container-closure system? 
 
2.3.S.3  Characterization 
The drug product applicant may reference a master file to address some questions in this 
section.  See individual questions for details. 
 
How was the drug substance structure elucidated and characterized? 
 
Reference to an MF is acceptable. 
 
Alternatively, a list of studies performed (e.g., IR, UV, NMR, MS, elemental analysis) and 
brief summary of the interpretation of evidence of structure should be provided.  Include a 
discussion of the stereochemistry of the drug substance, if applicable. 
 
What information should be provided for chiral drug substance? 
When the drug substance contains one or more chiral centers, the applicant should indicate 
whether it is a racemate or a specific enantiomer.  When the drug substance is a specific 
enantiomer, then tests to identify and/or to quantify the enantiomer should be included.  
Discussion of chirality should include the potential for interconversion between 
enantiomers (e.g., racemization/epimerization). 
 
If polymorphic forms are present, how were they characterized? 
 
9  Contains Nonbinding Recommendations 
There are a number of methods that can be used to characterize polymorphs of a drug 
substance.  Demonstration of a nonequivalent structure by single crystal X-ray diffraction 
is currently regarded as the definitive evidence of polymorphism.  X-ray powder diffraction 
can also be used to support the existence of polymorphs.  Other methods, including 
microscopy, thermal analysis (e.g., differential scanning calorimetry and thermal 
gravimetric analysis), and spectroscopy, are helpful to further characterize polymorphic 
forms. 
 
What attempts were made to identify and characterize potential impurities? 
 
Reference to an MF is acceptable.  The application or file for the drug product should 
include a list of potential impurities and their origins. 
 
Alternatively, list impurities (e.g., starting materials, by-products, intermediates, chiral 
impurities, degradation products) observed or considered to be potentially present in the 
drug substance.  Identify impurities by name or by other appropriate descriptor (e.g., 
RRT/HPLC).  The structure, if known, should be provided.  List analytical procedure used 
to detect or search for the impurity or the potential impurity.  The origin of the impurities 
should be provided (e.g., process impurity or degradant).  Indicate whether a potential 
impurity was actually detected in the drug substance and provide the limit of detection 
(LOD) or limit of qualification (LOQ) for the analytical method.  A detailed accounting of 
the impurities found in various batches should be provided in S.4.4.  The information can 
be provided in a tabular format such as below: 
 
Example 
ID  Chemical  Structure  Origin  Detected and  Analytical 
Name  LOQ/LOD  Method 
  [specified         
impurity] 
 
Is identification of potential impurities needed if there is a USP related substances method? 
Yes.  The USP monograph provides the minimum requirements for a drug substance.  
Impurities not included in the monograph may arise from different manufacturing 
processes and should be explored. 
 
2.3.S.4  Control of Drug Substance 
The drug product applicant may reference a master file to address some questions in this 
section.  See individual questions for details. 
 
   
10  Contains Nonbinding Recommendations 
What are the drug substance specifications? 
 
The drug product manufacturer should include the results for the batch(es) of drug 
substance used to produce the drug product.  The specifications should consider all of the 
critical drug substance attributes.  Test results and acceptance criteria should be provided 
as numerical values with proper units where applicable. 
 
How should this information be formatted? 
This information can be submitted in tabular format as shown below: 
 
Example 
Tests  Acceptance  Analytical  Test results 
criteria  procedure  (lot#) 
Appearance       
Identification       
A 
B 
Assay       
Specified impurities       
Impurity # 1 
Impurity # 2 
Impurity # 3 
Impurity # n, etc. 
Any unspecified impurity 
Total impurities 
Residual solvents       
[additional specifications]       
 
When is a drug substance particle size specification necessary? 
A specification should be included when the particle size is critical to either drug product 
performance or drug product manufacturing. 
 
How do the specifications compare to the USP? 
 
If the specifications do not conform to current USP, justify the differences.  If there is no 
USP monograph, all specifications should be justified. 
 
What type of justification is needed for the specifications for impurities? 
ICH/International Cooperation on Harmonisation of Technical Requirements for 
Registration of Veterinary Medicinal Products (VICH) limits and justification can be used 
for impurities.  All residual solvents should be identified and limits should be established. 
 
Applicants should develop impurity limits based on the MF holders synthetic process.  
Provide levels of impurities found in drug substance batches used in safety, clinical and 
comparative studies. 
11  Contains Nonbinding Recommendations 
Are the analytical methods suitable for their intended uses and validated or 
qualified? 
 
If using a method from an MF, you may provide an MF reference and a transfer study 
report. 
 
Provide a summary of each method and its validation/qualification.  The method summary 
can be in tabular or descriptive format and include the critical parameters for the method 
and system suitability criteria.  The validation summary can be in tabular or descriptive 
format and include results and acceptance criteria (including justification if necessary) for 
each parameter.  For each analytical procedure, provide a page number to the location of 
the validation information in Module 3.  Validation is required if the USP method is 
modified. If a drug substance has a USP monograph and the USP method is not used, then 
the method utilized should be demonstrated to be equivalent to or better than the USP 
method. 
 
The analytical test method(s) for assay and impurities used in the stability program should 
be shown to be stability indicating. 
 
What analyses were performed on the batches? 
 
Reference to a master file is acceptable. 
 
Alternately, provide batch analyses in this section in tabular format.  Information may 
include batch identity (i.e., batch number), batch size, manufacture date, manufacturing 
site, manufacturing process (if different from process described in S.2), and batch purpose 
(e.g., bioavailability, stability).  For quantitative data, the use of qualitative terms such as 
conforms or meets specification is generally not acceptable. 
 
2.3.S.5  Reference Standards 
The drug product applicant should provide information for all questions in this section.  
Reference to a master file is acceptable if the reference standard is supplied by the drug 
substance manufacturer.  The answer should also discuss reference standards for impurities, 
if used. 
 
Is the reference standard a USP standard? 
 
Is there a working standard? 
 
What is the expiry/retest of the standards? 
 
How are the reference standards certified/qualified? 
 
If the reference standard is obtained from the USP/NF (United States 
Pharmacopeia/National Formulary), then identify as such.  A reference standard that is not 
12  Contains Nonbinding Recommendations 
obtained from USP should be of the highest purity and fully characterized.  Include a COA 
in Module 3, along with details of the reference standards preparation, qualification, and 
characterization.  This should be summarized in Module 2.  Generally, the characterization 
information should include: 
 
  A brief description of the manufacture of the reference standard, if the process differs 
from the routine manufacturing procedure of the drug substance.  Any additional 
purification procedures used in the preparation of the reference standard should be 
described.  The purity of the reference standard should be stated. 
 
  Information to substantiate the proof of structure should be provided.  This may be 
performed utilizing a variety of analytical techniques, including UV, FTIR, NMR, MS, 
elemental analysis, specific optical rotation, DSC, TGA, and X-ray crystallography, 
as well as applicable functional group analysis.  Relevant data/results obtained with 
these techniques should be submitted.  For biotechnological/biological product 
reference standards, structure characterization may include, but not limited to, a 
determination of amino acid sequence, amino acid composition, peptide map, and 
carbohydrate structure.  Adequate description of the test procedures should be 
submitted.  Detailed interpretation of the test data in support of the claimed structure 
should be provided. 
 
An expiry/retest period should be proposed and supporting information submitted. 
 
If a secondary (in-house) standard is used in addition to the primary reference standard 
that was characterized as described above, this secondary standard should be qualified 
against the primary reference standard. 
 
2.3.S.6  Container Closure System 
The drug product applicant may reference a master file to address all questions in this 
section. 
 
What container closure system is used for packaging and storage of the drug 
substance? 
 
The primary and secondary containers need to be clearly identified, as do their materials of 
construction and manufacturer/supplier. Reference master files as appropriate. 
 
Does the primary container meet applicable CFR and/or USP requirements? 
 
The primary packaging material should meet 21 CFR Parts 172186 as applicable.  
Documentation should be provided from the supplier of the packaging materials certifying 
this conformance.  For other information related to packaging materials, reference to a 
Type III Drug Master File (DMF) or VMF is acceptable, with a Letter of Authorization 
from the DMF or VMF holder. 
   
13  Contains Nonbinding Recommendations 
What information is included on the label? 
 
The label should clearly indicate the storage conditions (with a numeric temperature range 
supported by long-term stability data), lot number, expiry/retest date, manufacturers name, 
site of manufacture, and statements required by 21 CFR  201.122.  Labels or copies of the 
label should be provided in Module 3. 
 
2.3.S.7  Stability 
The drug product applicant may reference a master file to address all questions in this 
section. 
 
What stability studies support the retest or expiry period and the storage conditions? 
 
Information should include a summary of the stability data in tabular format (e.g., ranges 
of results), the conclusions reached regarding stability, and the retest or expiry period. 
 
What are the conditions and tests for the stability program? 
 
What is the proposed commercial packaging and how does it compare with the 
packaging chosen for the stability program? 
 
What is the justification for the stability tests and specifications chosen? 
 
If there are any differences between release and stability specifications, provide 
justification. 
 
What are the stability protocol and post-approval stability commitment? 
 
The stability protocol should describe the test specifications (methods, acceptance criteria, 
etc.), testing intervals, storage conditions, retest or expiry period, and packaging. 
 
The post-approval stability commitment should include: 
  The first three production lots followed by 3-10% of the production lots (with a 
minimum of one lot per year); 
  A commitment to report the stability data annually; and 
  A commitment to withdraw from the market any production lot(s) found with out-of-
specification results and investigate those lots immediately before and after the lot(s) 
in question. 
 
For more details, see CVM GFI #5: Drug Stability Guidelines.vi 
 
   
14  Contains Nonbinding Recommendations 
III.  DRUG PRODUCT (2.3.P) QUESTIONS 
 
2.3.P.1  Description and Composition 
What is the dosage form (provide description)?  What are the components 
and composition of the final product?  What is the function of each excipient? 
 
What is the physical description of the drug product? What are the available 
strengths, route of administration, release mechanism, as well as any other 
distinguishable characteristics? 
An example of an appropriate response would be - The proposed drug product is 
available as an oval, round, immediate-release, aqueous film coated tablet in three 
strengths (5 mg, 10 mg, and 20 mg). 
 
What is the function of each component in the drug product? 
List in tabular format (see example table below).  Include all components used in the 
manufacture of the drug product (such as solvents and processing aids) even if removed 
during processing.  Indicate which components are compendial.  For each strength, list the 
quantitative composition of the finished dosage form.  Excipient grade should be discussed 
in 2.3.P.4 (Control of Excipients).  The total amount of material in pilot and production 
batches goes in 2.3.P.3 (Manufacture). 
 
Example 
Ingredient  Function  Weight/Tablet  % (w/w) 
[Drug substance]  Active     
[Excipient]       
[Solvent]  Solvent*  N/A  N/A 
Total weight       
*Removed during the manufacturing process. 
 
Does this product contain multiple processing steps? 
For example:  tablet cores or beads. 
 
What is the composition of the significant intermediates? 
 
Are there any overages in the formulation of the product?  What is the justification 
for the overages? 
Identify and justify any formulation overages that appear in the final product.  
Manufacturing overages should be discussed in 2.3.P.3. 
 
For animal generic drug products, note that, in general, the only acceptable justification 
for an overage in the final drug product formulation is the demonstration of a similar 
overage in the reference listed drug (RLD). 
 
   
15  Contains Nonbinding Recommendations 
Does this product contain any materials with sizes in the nanometer ranges (<1 m)? 
 
For generic products, do the differences between this formulation and the reference 
listed new animal drug (RLNAD) present potential concerns with respect to 
therapeutic equivalence? 
 
Describe any efforts taken to ensure the therapeutic equivalence to the RLD. If known, 
provide the formulation of the RLD. 
 
2.3.P.2  Pharmaceutical Development 
While the inclusion of a Pharmaceutical Development Report (PDR) is optional, a PDR 
provides a brief summary of the final drug product development.  CVM considers the 
information in the PDR, such as a description of the research that led to the evolution and 
selection of components, formulation, specifications, etc. of the final product, very helpful 
in demonstrating process understanding.  This may include information about alternative 
formulations that were tried and deemed not to be optimal.  Important aspects of a useful 
PDR are described below.  It is important to note that a PDR is most informative to CVM in 
describing why a component or a process was chosen. 
 
The studies included in a PDR are distinct from the routine control tests conducted 
according to specifications, such as release or stability testing.  Summary results from 
studies or references to relevant literature should be included in the PDR or as an 
attachment to the PDR. 
 
2.3.P.2.1 Components of the Product 
 
Applicants should explain the rationale behind the selection of the components of the drug 
productthe drug substance and the excipients used. 
 
2.3.P.2.1.1  Drug Substance 
 
Which properties or physical chemical characteristics of the drug 
substance affect drug product development, manufacture, or 
performance? 
 
What are the key physicochemical characteristics of the drug substance 
selected, in particular those that can influence the performance or 
manufacture of the final drug product? 
Physicochemical properties that may be of interest and concern include water 
content, solubility, particle size distribution, pH, pKa, or the existence of 
polymorphic forms. If the drug substance has been structurally modified from the 
active moiety, such as made into a salt, the applicant should discuss whether the 
modification will impact the manufacture and/or the quality of the drug product. 
 
16  Contains Nonbinding Recommendations 
Are any of the key physicochemical properties determined to potentially 
influence the performance of the drug product?  What studies were 
conducted to establish and to justify the drug substance specification? 
 
What drug substance(s) (including grade) was selected? 
 
Is there more than one drug substance in your product?  What evidence 
supports the compatibility of the drug substances with each other? 
If there is any incompatibility identified, justify the use of the drug substance with 
summary data, such as stability data or studies examining the impurities that 
arise from the interaction of the drug substance and the additional drug 
substance. 
 
2.3.P.2.1.2  Excipients 
 
What evidence supports compatibility between the excipients and the 
drug substance? 
 
What compatibility screening was performed during the pre-formulation 
stage? 
Discuss the issue of compatibility of the drug substance with the excipients in the 
drug product.  The compatibility study should include a simulation of the most 
extreme conditions that the drug substance and excipients will be subjected to 
during the actual manufacturing process.  The design and results of the screening 
should be provided and discussed. 
 
Were any excipients found to be incompatible with the drug substance or 
with each other?  Which excipients were found to be incompatible, and how 
was their selection justified? 
Any excipients which were found to be incompatible with the drug substance 
should be identified.  The selection of the excipients used in the final formulation 
should be justified using the results of the compatibility screening. 
 
For generic products, were any attempts made to determine what excipients 
were used in the pioneer product? 
If the excipients in the pioneer product being copied are not defined, describe 
attempts made to determine what they were.  If identification was confirmed, and 
a decision was made to intentionally use different excipients, provide justification 
for using the ones ultimately chosen for use in the final formulation.  If 
identification was not attempted or was not possible, provide rationale for the 
excipients chosen. 
 
   
17  Contains Nonbinding Recommendations 
2.3.P.2.2 Drug Product 
 
What attributes should the drug product possess?   
 
Are there critical attributes that ensure product quality for the intended use and route 
of administration?  Describe the critical attributes. 
This section should identify and describe the formulation and process attributes (critical 
parameters) that may influence batch reproducibility, product performance and drug 
product quality. 
 
Is the drug product an immediate release or controlled release? Describe the release 
mechanism. 
The specific release mechanism should be described and the development studies leading to 
the final release mechanism should be summarized.  The type of information may vary 
substantially since the development of release mechanisms will vary between different 
formulations, such as coated tablets versus in-situ forming gels. 
 
How was the drug product designed to have these attributes? 
 
For release profiles, how does the product achieve the desired profile? 
For example, does it use an enteric coating or slow release matrix. 
 
Are any overages used in the drug product?  Why is an overage necessary? 
The applicant should describe and justify the amount of the overage if needed to ensure 
dose delivery.  This overage should also be included in the composition and batch formula. 
 
Are there any special design features of the product? 
A rationale should be given for these design features to support their appropriateness. 
 
Were alternative formulations or mechanisms investigated? 
 
What formulations were used to produce the clinical batches for safety and 
effectiveness studies? 
 
Are there differences in formulation between the clinical or pilot batches and that 
proposed for commercial batches?  Describe the different formulations. 
Applicants should provide the complete list of formulations in the evolution of the final 
formulation.  The rationale or justification should be given for differences in formulations 
between the commercial and clinical or stability batches.  This information may include 
comparative in vitro or in vivo studies to link the clinical formulation(s) with the proposed 
commercial formulation. 
 
   
18  Contains Nonbinding Recommendations 
How were the excipients and their grades selected? 
 
What excipients were chosen for use in the final formulation and what are their roles 
in the drug product (e.g., anti-dusting agent, binding agent)? 
The applicant should briefly explain and/or justify the selection of each excipient for its 
particular role in the drug product and provide evidence that the excipients can fulfill their 
intended role.  Reference to 2.3.P.2.1.2, when applicable, is acceptable. 
 
Are there multiple grades of an excipient available?  What are the different grades 
and the properties that distinguish one grade from another (e.g., viscosity, particle size 
distribution)? 
The applicant should provide justification for the use of one grade over another.  If a USP 
monograph exists for the excipient, it can be used as a reference.  If there is no USP 
monograph, the applicant should provide and justify specifications which ensure the quality 
of the excipient(s). 
 
Does the excipient exert a critical function related to the product performance?  What 
studies were executed to evaluate the appropriateness of multiple grades of that 
excipient for use with the drug substance and any other excipients? 
The applicant should provide the results of any such studies.  Reference to 2.3.P.2.1.2 is 
acceptable. 
 
How was the final formulation optimized? 
 
What studies were conducted that led to the final formulation? 
 
Which formulations revealed the most useful information? 
Indicate what the sponsor learned about what components are critical or non-critical to 
product performance. 
 
Why was the formulation selected over other possible variations using the same 
components? 
 
2.3.P.2.3 Manufacturing Process Development 
 
Why was the manufacturing process described in 2.3.P.3 selected for this 
drug product? 
 
The sponsor should first describe the choice of a manufacturing process at a high level.  
For example, for a solid oral dosage form the sponsor should explain the choice between 
direct compression versus wet granulation or other approaches. 
 
   
19  Contains Nonbinding Recommendations 
What factors were considered in the selection of the manufacturing process - including 
the properties of the drug substance, the desired properties of the drug product, and 
the complexity and robustness of the process? 
Once the process was selected, a sponsor should focus on describing particular steps for 
which there are alternatives available (for example rationale for the selection of high shear 
granulation versus fluid bed granulation) and explain the motivation for each choice. 
 
How are the manufacturing steps (unit operations) related to the drug 
product quality? 
 
What are the critical steps in the manufacturing process? 
 
What studies established links between unit operations and the target product profile 
(through pilot scale studies or prior knowledge)? 
A sponsor should demonstrate which unit operations are critical to which drug product 
properties.  It may be useful to present this information in the form of a matrix between unit 
operations and quality attributes.  Once a step is identified as being critical then the 
sponsor should design their process to ensure that this step succeeds or have tests in place 
to detect if the step fails. 
 
How were the critical process parameters identified, monitored, and/or 
controlled? 
 
A critical process parameter (CPP) is any measurable input (input material attribute or 
operating parameter) or output (process condition or output material attribute) of a 
process step that must be controlled to achieve the desired product quality and process 
consistency.  Scale independent CPPs, such as material attributes, are the most valuable, 
because they can be directly used for scale up.  For example, a material attribute CPP, 
such as moisture content, should have the same target value in the pilot batch process and 
the commercial scale process.  An operating parameter CPP, such as air flow rate, would 
be expected to change as the process scale changes. 
 
What is the scale-up experience with the unit operations in this process? 
 
Valuable experience includes experience with other products using the same unit 
operations, literature references/vendor scale-up factors, the lab scale to pilot batch 
process transfer for this product, pilot batch production, as well as modeling and 
dimensional analysis. 
 
What resulting plan was developed to scale-up the process to commercial scale and 
how was this scale-up plan developed? 
This should include identification of operating parameters that may be scale dependent and 
process monitoring (in excess of meeting regulatory specifications) that ensures the 
commercial scale process will be equivalent to the process that produced the pilot batch. 
 
20  Contains Nonbinding Recommendations 
2.3.P.2.4 Container Closure System 
 
What specific container closure attributes are necessary to ensure product 
performance? 
 
How were materials for the container-closure system chosen (e.g., to provide light 
protection or minimize leachability)? 
Standards for the selection and testing of glass and plastic containers to demonstrate their 
acceptability for use are provided in USP 4 <660> vii and <661>,viii respectively. 
 
What studies to determine the compatibility of materials with the drug product were 
performed? 
For drug products that incorporate delivery devices (e.g., inhalation devices, spray pumps), 
pharmaceutical development studies conducted to select the device should be discussed in 
this section. 
 
2.3.P.3  Manufacture 
See CVM GFI #42: Animal Drug Manufacturing Guidelines ix for information intended to 
provide guidance for the submission of appropriate manufacturing data and information to 
support the approval of an original (A)NADA. 
 
Who manufactures the drug product? 
 
What are the names, addresses, and responsibilities of each manufacturer and each 
proposed production site or facility? 
All manufacturers and contractors, such as contract sterilization, and all facilities involved 
in the manufacturing, testing, packaging, storage, and labeling should be identified.  
Building numbers or other specific identifying information should be provided for multi-
facility campuses. 
 
Is there a U.S. Agent for any of the manufacturers identified?  If so, what is the 
contact information for each U.S. Agent? 
US Agents for all foreign facilities should be identified. 
 
Does any proposed production site or facility process sterile drug substances, drug 
products, or packaging components?  If so, where are the sterile processing area(s)? 
The sterile processing area may be described by room number, filling line, or other 
appropriate identifiers.  Reference to a Type V VMF is acceptable with a Letter of 
Authorization (LOA) and identification of a US Agent (if applicable). 
   
                                                 
 
4 United States Pharmacopoeia:  http://www.usp.org/ 
21  Contains Nonbinding Recommendations 
 
How do the manufacturing processes and controls ensure consistent production of 
drug product? 
 
What manufacturing processes and controls are used for production of the finished 
drug product? 
This may include flow chart(s), detailed description of the process, critical manufacturing 
processes and controls, specifications for raw materials, and acceptance criteria for in-
process tests. 
 
Is a flow chart(s) of the manufacturing process provided? 
A flow chart gives the steps of the process and shows where materials enter the process.  
The entire manufacturing process from the weighing of components through finished 
product release is generally pictured.  The flow chart often includes the following: 
 
a.  Description of each manufacturing step 
b.  Identification of the material being processed 
c.  Identification of the critical process controls and point at which they are tested 
d.  Identification of the type of equipment used 
 
The manufacturing process description represents the sequence of steps undertaken to 
produce a finished drug product.  This description provides more detail than that provided 
in the flow chart and generally includes the following elements: 
 
a.  The complete manufacturing process for each drug product (e.g., strength, packaging 
configuration), including the scale of production 
b.  Identification of equipment by type (e.g., tumble blender, in line homogenizer) and 
working capacity where relevant.  This is most relevant for tableting and sterile 
operations. 
c.  A detailed description of any novel processes or technologies and packaging 
operations that directly affect product quality 
d.  Identification of all process controls, including the critical process controls and the 
associated numeric ranges, limits, or acceptance criteria 
 
Does the batch formula accurately reflect the drug product composition?  If not, 
what are the differences and the justifications? 
 
Is a batch formula provided for the drug product composition?  What are the 
amounts of all the components, including overages, used in the manufacturing 
process? 
Any explanatory notes (e.g., actual amount added based on purity) should be described for 
the batch formula.  All ingredients should be included in the batch formula whether or not 
they remain in the finished product (e.g., processing agents such as water, ethanol, and 
nitrogen or other gases). 
 
22  Contains Nonbinding Recommendations 
The batch formula included in the batch record should be the same as the batch formula 
included in the product composition section.  Batch record information is provided in 
Module 3 under section 3.2.R.P.1 or 3.3.P.3.3.  The batch record may include the following 
information: 
 
a.  Batch identity (i.e., lot number), strength, and size 
b.  Use of batch (e.g., bioavailability, stability) 
c.  Date of manufacture 
d.  Site of manufacture 
e.  Batch number and manufacturer of the drug substance used in the drug product 
f.  Batch number and manufacturer of novel excipients or any excipients that are critical 
to product performance (e.g., excipients used to form liposomes) 
g.  The steps of the manufacturing process, including identification of the equipment, 
manufacturing time (start and end of operating), material handling 
h.  Identification of each in-process control, including the sampling technique, test 
specifications, and test results, as appropriate (The results of the testing should be 
expressed numerically or qualitatively, e.g., clear, colorless solution.  Use of terms 
such as conforms or meets specification is discouraged) 
i.  Container closure system 
j.  Weight/Volume Checks  there are often two people initialing each step. 
k.  Yields (theoretical/actual yield, calculation) 
l.  Packaging and Labeling (packaging and labeling precautions to assure correct 
labeling, packaging) 
m.  Specifications for the release of the finished drug product 
 
What are the quality standards for each component used in the manufacturing 
process? 
 
What are the in-process controls that ensure each step is successful? 
 
In-process controls are tests and controls used during production to monitor and, if 
appropriate, adjust process parameters and/or to ensure an in-process material meets 
established acceptance criteria.  Examples of process parameters and attributes that may 
be monitored are: 
 
a.  Operating parameters -- parameters that can be adjusted to control the 
manufacturing process (e.g., temperature, pH, time, mixing speed) 
b.  Environmental conditions -- conditions associated with the manufacturing facility 
(e.g., temperature, humidity, clean room classification) 
c.  Quality attributes of in-process materials 
 
What in-process specifications were established? 
Specifications should include the tests and acceptance criteria used to monitor and assess 
the performance of the process and the quality attributes of in-process materials. 
 
   
23  Contains Nonbinding Recommendations 
Which in-process controls are used to monitor critical process parameters? 
A critical process parameter is one whose variability impacts a quality attribute of the drug 
product, and therefore needs to be controlled to ensure that the process produces the 
desired quality. 
 
Depending on the drug product and manufacturing process, a particular process parameter 
may or may not be critical as illustrated in the following examples: 
 
  Mixing speed range can be critical for forming an emulsion, but may not be critical 
for mixing a chemical solution. 
  The humidity in the manufacturing facility can be critical for an effervescent tablet 
but may not be critical for an ointment. 
  The clean room classification, while critical for a sterile product, may not be critical 
for a non-sterile product. 
  The time frames for certain unit operations or overall drug product production can 
be critical for some products (e.g., blending time, hold times during sterile 
processing) 
 
Tests and acceptance criteria (with justifications for acceptance limits) performed at the 
critical steps of the manufacturing process should be provided to ensure that the process is 
controlled. 
 
What is the reconciliation of the batch? 
 
Reconciliation is a comparison of the actual yield to the theoretical yield of a batch.  The 
reconciliation includes an account of materials (e.g., labels), a description of the 
accounting for such items as discards, breakage, etc., and the criteria used in accepting or 
rejecting batches of drugs in the event of an unexplained discrepancy. 
 
What is the difference in size between commercial scale and pilot batches and does 
the equipment use the same design and operating principles? 
 
The equipment used for each scale should be briefly described and any differences in 
operating principles should be indicated. 
 
Were developmental studies used to justify limits or identify critical parameters prior 
to execution of the pilot batch?  What differences between equipment used in 
developmental studies and pilot batches are relevant to quality attributes of the 
material generated? 
An illustrative example is included in the following table below: 
 
   
24  Contains Nonbinding Recommendations 
Example 
Unit  Equipment  Development  (A)NADA  Commercial  Rationale 
Operation  Studies  Batch  Batch  for 
[kg/batch]  [kg/batch]  [kg/batch]  Change 
[units/batch]  [units/batch]  [units/batch] 
[Process  [Equipment  [brand and  [brand and  [brand and   
step]  class]  size]  size]  size] 
[Process  [Equipment  [brand and  [brand and  [brand and   
step]  class]  size]  size]  size] 
 
What is the rationale for differences in equipment, critical or quality related steps and 
controls? 
For some changes, the rationale may be as simple as due to larger batch size a larger bin 
blender was required, whereas, more complex changes (e.g., change in operating 
parameters) should be supported by data (reference to the Pharmaceutical Development 
Report is acceptable). 
 
What evidence supports the plan to scale up the process to commercial scale?  What 
operating parameters will be adjusted to ensure the product meets all in-process and 
final product specifications? 
 
The plan to scale up the process to commercial scale may be supported by understanding of 
formulation, manufacturing process, and equipment or by information generated during the 
drug development phase. 
 
Do you have prior experience with other products using the same unit operations, 
literature references/scale-up factors, or modeling and dimensional analysis to support 
scale up?  Describe your prior experience. 
If this or similar information is available, it may provide valuable information to support 
your process knowledge. 
 
Are the process description and the in-process and release specifications fixed or likely 
to change prior to scale-up?  How will scale-up affect these steps or specifications? 
The sponsor has the flexibility to adjust the operating parameters (e.g., time, flow rate, 
temperature) to meet these constraints during scale-up.  For commercial scale-up, a 
sponsor may either propose fixed ranges for these operating parameters in a proposed 
master batch record or indicate that an operating parameter will be adjusted to reach a 
desired end-point.  An illustrative example is included in the following table below: 
 
   
25  Contains Nonbinding Recommendations 
Example 
Operating  Pivotal Batch  Proposed Commercial  Rationale 
Parameter  Scale 
Unit Operation #1 
Parameter 1  Value or range  Value or range  Adjust to meet end-point 
Parameter 2  Value or range  Value or range  Scale-independent 
variable 
Parameter 3  Value or range  Value or range  Linear scale-up rule 
established in PD 
Unit Operation #2 
Parameter 1  Value or range  Value or range   
 
What additional rationale supports scale-up? 
All rationale should be provided and should focus on critical steps in the manufacturing 
process.  This rationale should build on the experience (including problems that were 
identified and resolved) obtained during development and/or the production of the pilot 
batch(es). 
 
2.3.P.4  Control of Excipients 
What are the specifications for the excipient ingredients and are they suitable for 
their intended function? 
 
Provide COAs from supplier/vendor, and your qualification of results, for all excipients in 
Module 3. 
 
USP Excipients 
Are USP/NF excipients being utilized? 
 
What are the USP/NF excipients utilized and their specifications? 
 
Are there any differences between the provided specifications and USP/NF 
specifications? 
 
What are the differences and justification for these differences? 
 
What format should be used for presenting the excipient specifications? 
For USP excipients a table indicating the grade is requested.  Justify any differences from 
USP/NF tests. 
 
   
26  Contains Nonbinding Recommendations 
Example 
Ingredient  Manufacturer  Grade  Lot Numbers*  Complies with 
Supplier  Applicant  USP/NF 
[Excipient]         
*Lot numbers used in the production of the pilot batch. 
 
Are there any excipients with additional specifications that are in excess of those 
included in the USP/NF? 
 
What are these excipients and their specifications? 
 
What is the justification for the additional specifications? 
 
What format should the sponsor use for presenting specifications in excess of USP/NF 
specifications? 
In this event, a sponsor should include a table for each excipient that has additional 
specifications.  These additional specifications should be justified.  Reference to 2.3.P.2.2 
(Pharmaceutical Development Report) is acceptable. 
 
Example 
Tests  Acceptance Criteria  Analytical Procedure  Batch Number 
[Extra      [Results from excipient 
Test]  batch] 
 
Non-USP Excipients 
Are non-USP/NF excipients being utilized? 
 
What are the non-USP/NF excipients utilized and their specifications? 
 
What is the justification for the specifications utilized for non-USP/NF excipients? 
 
What information is requested for non-USP excipients? 
The specifications for the non-USP excipient should be included in the QOS in a tabular 
form.  Provide justification for specifications (may be provided in Pharmaceutical 
Development Report).  The grade used should also be indicated. 
 
Excipients from Animal Origin 
Are there excipients from animal origin? 
 
What excipients are from animal origin and what information will allow CVM to 
assess the suitability of the supplier as it relates to TSE and other adventitious agents? 
Reference the location of BSE/TSE certification, country of origin shall be provided, as 
applicable. 
27  Contains Nonbinding Recommendations 
 
Novel Excipients 
Are any novel excipients being utilized? 
Novel excipients are those that have not been previously used in veterinary drug products.  
Novel excipients are generally not used in an ANADA product as safety and effectiveness 
information is not available. 
 
What novel excipients are being utilized and what additional details are available to 
support their use? 
These excipients may require additional details including manufacture, characterization, 
controls, or a DMF/VMF reference. 
 
What information supports the suitability of the excipients for their intended 
functions? 
 
How do I show that an excipient is suitable for its intended function? 
The known functions of common excipients are sufficient to determine suitability.  For 
example, magnesium stearate is used as a lubricant in the manufacture of immediate-
release tablets.  For novel excipients or novel uses of common excipients, describe studies 
that identified the critical attributes of that excipient (reference can be made to the 
pharmaceutical development report). 
 
What is your vendor qualification program? 
 
A description of your vendor qualification program should be provided.  Initial 
qualification should include analysis of the first three lots received from a vendor to 
confirm their COA results, and the manufacturer should perform re-qualification testing for 
these excipients at least once per year. 
 
Who manufactures the excipients? 
Provide the name and address of each excipient manufacturer.  Identify the U.S. Agent (if 
applicable). 
 
2.3.P.5  Control of Drug Product 
What is the drug product specification and does it include all the critical drug 
product attributes? 
 
The drug product manufacturer should include the full release specifications.  Acceptance 
criteria should be provided as numerical values with proper units where applicable.  
Dosage form specific tests should be included as appropriate (e.g., dissolution, uniformity 
of dosage units, water content, microbial limits, etc.) and their inclusion justified. 
 
   
28  Contains Nonbinding Recommendations 
See CVM GFI #176/VICH GL39: Specifications: Test Procedures and Acceptance Criteria 
for New Veterinary Drug Substances and New Medicinal Products:  Chemical Substances.x  
It provides guidance on the setting and justification of acceptance criteria and the selection 
of test procedures for new medicinal products. 
 
Does the drug product conform to a USP monograph? 
 
How do the specifications compare to the USP?  If the specifications do not conform 
to current USP, justify the differences. 
 
If the drug product has a USP monograph, is there a difference between the USP 
monograph and the limits proposed? 
 
What is the justification? 
 
Are the analytical methods suitable for their intended uses and validated or 
qualified?  What is the justification of the validation acceptance criteria? 
 
Provide a summary of each method and its validation/qualification. 
 
The method summary should include the critical operational parameters.  The validation 
summary should include results and acceptance criteria for each parameter.  For each 
analytical procedure, provide a page number to the location of the validation information 
in Module 3.  Validation is required if the USP method is modified or if there is no USP 
method (see CVM GFI #64: Validation of Analytical Procedures: Methodology xi).  If a 
USP method exists and is not used, then the proposed method should be demonstrated to be 
equivalent to or better than the USP method. 
 
For each analytical test method for assay used in the stability program, what 
information demonstrates it is a stability indicating method? 
 
Are impurities quantified using impurity reference standards? What are the relative 
response factors for impurities? 
 
What is the batch control numbering system for the finished product? 
 
Is the batch analysis data included? 
 
What are the batch analysis results for all pilot and clinical batches, including those 
used for stability studies? 
Batch analyses should at least include release testing results.  The batch analysis reports 
and collated batch analyses data should also include the following information: 
 
  Batch identity (i.e., batch number), strength, and size 
  Date of manufacture 
  Site of manufacture 
29  Contains Nonbinding Recommendations 
  Manufacturing process, where applicable 
  Container closure system 
  Use of batch 
  Batch number and manufacturer of the drug substance used in the drug product 
  Batch number and manufacturer of novel excipients or any excipients that are critical 
to product performance 
 
Test results should be expressed numerically or qualitatively (e.g., clear, colorless 
solution), as appropriate.  Quantitative results should not be reported in general terms such 
as complies, conforms, or meets limit.  Results below the LOD or LOQ for 
validated methods should not be reported as 0, but rather as less than the value of the 
LOD or LOQ. 
 
What are the impurities of the drug product? 
 
What are the potential drug product impurities? 
Information on the drug product impurities (see CVM GFI #93/VICH GL11(R): Impurities 
in New Veterinary Medicinal Products (Revised) xii) should be provided.  All potential drug 
product impurities should be listed in this section of the application whether or not the 
impurities are included in the drug product specification. 
 
Which potential impurities are included in the drug product specification? 
Provide justification for any potential impurities not included in the drug product 
specification. 
 
What characterization studies (i.e., structural characterization) were performed for 
the impurities? 
 
2.3.P.6  Reference Standards and Materials 
Provide information about reference standards used to test the finished product and raw 
materials.  Information for the drug substance can be referenced back to section 2.3.S.5. 
 
Is the reference standard a USP standard? 
 
Is there a working standard? 
 
How are the reference standards certified/qualified? 
 
If the reference standard is obtained from the USP/NF, then identify as such. 
 
A reference standard that is not obtained from USP should be of the highest purity and fully 
characterized.  Include a COA as a supporting document in Module 3, along with details of 
the reference standards preparation, qualification, and characterization.  This information 
should be summarized in Module 2.  Generally, the characterization information should 
include: 
30  Contains Nonbinding Recommendations 
 
  A brief description of the manufacture of the reference standard, if the process differs 
from the routine manufacturing procedure of the drug substance.  Any additional 
purification procedures used in the preparation of the reference standard should be 
described.  The purity of the reference standard should be stated. 
  Information to substantiate the proof of structure should be provided.  This may be 
performed utilizing a variety of analytical techniques, including UV, FTIR, NMR, MS, 
elemental analysis, specific optical rotation, DSC, TGA, and X-ray crystallography, 
as well as applicable functional group analysis.  Relevant data/results obtained with 
these techniques should be submitted.  For biotechnological/biological product 
reference standards, structure characterization may include, but is not limited to, a 
determination of amino acid sequence, amino acid composition, peptide map, and 
carbohydrate structure.  Adequate description of the test procedures should be 
submitted.  Detailed interpretation of the test data in support of the claimed structure 
should be provided. 
  An expiry/retest period should be proposed and supporting data submitted. 
 
If a secondary (working) standard is used in addition to the primary reference standard 
that was characterized as described above, this secondary standard should be qualified 
against the primary reference standard. 
 
The answer should also discuss reference standards for impurities, if used. 
 
2.3.P.7  Container Closure System 
What container closure system(s) is proposed for packaging and storage of 
the drug product? 
 
How should the information for the container closure system be presented? 
In tabular form, provide a summary of the container closure systems used.  Include the 
different packaging configurations, size of container closure for each configuration, units 
per packaging configuration, and the manufacturer/supplier and DMF or VMF numbers.  If 
a DMF or VMF is referenced, a letter of authorization to reference the file should be 
provided. 
 
Example 
Type  Description (Packaging Configuration)  Supplier  DMF or 
[Component]  [Description] (Packaging that uses this)  VMF 
Bottle  60 mL white square HDPE (60,100 tablets)     
 
Has the container closure system been qualified for use with this drug 
product? 
 
Do the packaging materials meet FDA and USP requirements? 
 
31  Contains Nonbinding Recommendations 
What testing or certification supports the safety of the packaging with the drug 
product? 
Examples include those tests described in the USP (e.g., USP<661> xiii).  Reference to the 
suppliers DMF or VMF may be appropriate. 
 
Provide any other testing or certification such as 21 CFR references (Federal Regulations 
under 21 CFR sections 174-186 provide a list of materials that are safe for use in direct or 
indirect food contact). 
 
A statement may be provided referencing products that have been approved using the same 
packaging system.  However, a copy of the test results that qualify the container closure 
system as safe should be provided in the referenced body of data. 
 
Are copies of the label provided? 
 
If the label is not final, provide the language used in the draft label to indicate CMC 
relevant information, such as storage conditions (e.g., numeric temperature range), active 
ingredients, how supplied, space for expiration date and lot number, and any special 
instructions (e.g., The stopper may only be punctured 35 times.). 
 
2.3.P.8  Stability 
What are the specifications for stability studies, including justification of 
acceptance criteria that differ from the drug product release specification? 
 
The description of stability specifications should include the test methods, acceptance 
criteria, etc.  If there are any differences between release and stability specifications, 
provide justification. 
 
What stability studies support the proposed shelf life and storage conditions? 
 
Information should include a summary of the stability data in tabular format (e.g., ranges 
of results), the conclusions reached regarding stability, and the expiry period.  Include 
results of accelerated stability studies, if the accelerated data is needed to support proposed 
expiry or label stated storage conditions. 
 
What are the post-approval stability protocol and commitment? 
 
What are the post-approval stability specifications (methods, acceptance criteria, 
etc.)? 
 
What are the stability storage conditions and testing intervals? 
 
What packaging is used for stability samples? 
 
   
32  Contains Nonbinding Recommendations 
What is the proposed post-approval stability commitment? 
 
The post-approval stability commitment should include: 
  A commitment to place the first three production lots followed by 3-10 % of the 
production lots on stability (with a minimum of one lot per year); 
  A commitment to report the stability data to CVM in a Minor Changes and Stability 
Report annually; and 
  A commitment to withdraw from the market any production lot(s) found with out-of-
specification results and to investigate those lots immediately before and after the 
lot(s) in question. 
 
For more details, see CVM GFI #5: Drug Stability Guidelines.xiv 
 
IV.  STERILE PROCESS VALIDATION QUESTIONS:  ASEPTIC PROCESSING 
 
Buildings and Facilities 
 
Is this information for your sterilization process referenced in a Type V master file? 
 
Provide letter of authorizations to master files, if necessary. 
 
What are the critical areas and supporting clean areas used in the manufacturing 
operations of the product? 
 
Provide floor plans for these critical areas and supporting clean areas, including aseptic 
processing area, air class designations, material/component flow, and personnel 
movement. 
 
Process 
 
What are the unit operations in the aseptic process? 
 
For example:  lyophilization, filtration 
 
What filling line was used for production? 
Identify the filling line(s) that will be used during production by line number and / or room 
number. 
 
What types of sterile equipment were used during production? 
For example:  tanks, filter housings, barriers, isolaters, etc.  The process simulation should 
incorporate the equipment listed here. 
 
   
33  Contains Nonbinding Recommendations 
What are the normal sterile production parameters for this product? 
These should include all vial sizes used, volume filled into each unit, the number of units 
filled per production run, line speed, and the duration of fill times.  Proposed hold times 
should also be included.  Validation of these parameters is addressed in the section that 
describes process simulations. 
 
How are aseptic connections made during production? 
Describe the environmental monitoring that occurs while the aseptic connections are being 
made.  The SOP describing how aseptic connections are made should be referenced in the 
batch record. 
 
Is the product directly filled into vials or filtered into a surge tank? 
If a surge tank is used, identify the size, its location and how it is sterilized. 
 
If you intend to use campaigns in normal production of this product, what is the 
proposed duration of those campaigns? 
CVM considers campaigns to be the number of batches produced without cleaning in 
between. 
 
Is lyophilization of the finished drug product or sterile API proposed? 
If so, provide a description or schematic of the lyophilizer, load diagram(s), and a floor 
plan showing flow of product from the filling area to the lyophilizer. 
 
Provide a narrative explaining the transportation of containers from the filling area to the 
lyophilizer and procedures taken to protect the containers from contamination. 
 
Specify the lyophilization steps and cycle parameters including but not limited to the 
loading of the trays, preparation phase, e.g., pre-lyophilization shelf temperature, and the 
primary and secondary phases. Provide the duration, temperature and chamber pressure of 
each phase. 
 
Document the procedures used for sterilizing the chamber and provide the supporting 
validation data (biological data, cycle data, where applicable). See the Steam in Place 
section of the Sterilization of Equipment section for information that should be included in 
this section. 
 
Are thermocouples used to monitor the temperature in the lyophilization chamber during 
routine production? 
 
Filtration 
 
How is the product filtered? 
 
34  Contains Nonbinding Recommendations 
Describe the filtration process.  Information provided here should include whether the 
production filters are sterilizing or clarifying, the number of filters used, the pore size of 
the filters, the filter manufacturer, and the composition of the filters used. 
 
How is filter integrity examined during production? 
Describe the method used to measure filter integrity.  Specify whether integrity testing was 
performed before and after product filtration. 
 
How do the filters used during filter validation compare to the filters used during 
production? 
Information provided here should include the composition of the filters used. 
 
What parameters were used during filter validation? 
Were worst case parameters used in the validation?  Describe the parameters used.  For 
example:  how many times the filter was autoclaved, product exposure time, temperature, 
pressure. 
 
What method was used to determine filter compatibility during filter validation? 
Provide a summary of the results of these tests.  Describe the studies performed and 
parameters used to determine compatibility. 
 
What method was used to determine filter extractables during filter validation? 
Provide a summary of the results of these tests.  If applicable, justification for the presence 
of these extractable materials should be provided. 
 
What method was used to determine drug adsorption to the filter during filter 
validation? 
Provide a summary of the results of these tests. If applicable, describe the steps performed 
to eliminate this adsorption. 
 
What method was used to determine bacterial retention during filter validation? 
This information should include whether the tests were performed in one or two parts, the 
organism used, and if simulated or actual product was used as the challenge solution.  If a 
simulated product was used, provide a description of the simulated product.  Also, the time 
the product was recirculated through the filter and the pressure used should be included. 
 
Describe the method used to determine filter integrity during filter validation.  State 
whether testing was done before and after the bacterial challenge or only after the 
challenge. 
 
Provide a summary of the results of these tests. 
 
   
35  Contains Nonbinding Recommendations 
Process Simulations (also known as media fills) 
 
What are the parameters evaluated during the process simulations to ensure the 
efficacy and consistency of the process? 
 
Describe the simulated product formulation and characteristics. If not media, provide a 
justification for the use of a simulated product. 
 
What filling line was used for the process simulation? 
This should be the same filling line used during production. 
 
What types of sterile equipment were used during the process simulation? 
This should be the same equipment used during production.  If there are similar equipment 
types, these should be rotated during process simulation re-qualifications so that they are 
periodically used during a process simulation. 
 
What is the number of units filled versus the number of units incubated? 
 
How many process simulations were performed and when were they conducted? 
Provide a justification for the number of process simulations performed if less than three. 
 
What incubation conditions are used for units from the process simulation? 
 
How does the process simulation simulate the production parameters? 
Specify line speed, fill volume, number of containers filled, duration of fill, etc.  Specify any 
down time during duration of fill.  If a campaign is used, specify whether the process 
simulation simulates the duration of the campaign or is performed at the end of a 
production campaign to simulate worst-case conditions. 
 
What are the hold times validated by the process simulation? 
These should be the same as those proposed for use during production. 
 
Is a matrix or bracketing approach proposed? 
Provide the justification for the proposed approach. 
 
What method is used to perform growth promotion testing? 
The acceptable organisms are described in USP <71> Sterility Tests. xv  If you are 
performing growth promotion concurrently with the process simulation incubation, 
describe how you are confirming the identity of the positive controls and how you are 
ensuring that the growth is not from an organism introduced during the process simulation 
process. 
 
   
36  Contains Nonbinding Recommendations 
Were there any positive units during the process simulation? 
Provide the acceptance criteria for process simulations and actions that will be taken in 
the event of one or more positive units. 
 
What is the requalification schedule for process simulations in the filling room? 
 
Is any reprocessing of components or product proposed? 
Additional questions addressing this topic are found in the section that describes stability 
considerations. 
 
Is lyophilization of the finished drug product or sterile API proposed? 
If so, include a comparison of the lyophilization process and how it is simulated during the 
process simulation. 
 
If a bracketing approach is proposed, provide a description of and justification for the 
proposed approach. 
 
Describe how the containers were exposed to the vacuum (e.g., whether unsealed and 
frozen or unfrozen containers were used, partial vacuum was pulled, and whether an 
aerobic environment was maintained, etc.) 
 
Steam-In-Place 
 
Is steam-in-place used for sterilization of equipment? 
 
What are the characteristics of the process that demonstrate the thermal 
qualification of the cycle?  How were the critical process parameters selected, 
validated, and monitored? 
 
What cycle parameters were used for validation and production runs?  For example: cycle 
time and temperature setpoint(s) 
 
What equipment is sterilized? 
 
What are the acceptance criteria for the qualification of the cycle?  How were these 
developed? 
For example: F  
0
 
How were locations of thermocouples selected? 
Describe how the cold spots were determined. Provide a rationale for the locations of the 
thermocouples. 
 
What were the results of the heat penetration studies? 
 
37  Contains Nonbinding Recommendations 
What is the requalification schedule? 
 
Component Preparation 
 
Are containers / closures depyrogenated in-house or depyrogenated by the supplier of 
the component? 
If depyrogenated in-house, was depyrogenation performed by dry heat or washing? 
 
If dry heat, was a tunnel or dry heat oven used? 
 
If depyrogenation is not done in house, then provide a reference to the master files 
associated with the depyrogenation of the component(s) if applicable.  If you utilize a 
process that does not allow for endotoxin contamination (i.e., blow-fill-seal), provide an 
explanation.  If you purchase a component which is not depyrogenated prior to use, 
provide a justification for the use of these components as well as data or a reference to a 
master file to demonstrate that the component is naturally low or free of pyrogens. 
 
What are the characteristics of the process that demonstrate the qualification of the 
endotoxin removal process?  How were the critical process parameters selected, 
validated, and monitored? 
What cycle parameters were used for validation and production runs?  For example: 
temperature setpoint(s), belt speed.  What are the acceptance criteria for the qualification 
of the cycle?  How were these developed?  For example:  3-log reduction in endotoxin.  
What loading patterns were used?  Were diagrams of the various loading patterns 
provided?  Written descriptions and / or diagram showing locations of thermocouples and 
endotoxin-spiked components are useful.  Diagrams of loading patterns may be submitted 
in Module 3.  What is the source of the endotoxin used?  Was the concentration of 
endotoxin verified?  Was a representative COA for the control standard endotoxin 
provided to Module 3?  How was the endotoxin inoculated onto the component? How was 
recovery performed?  What is the requalification schedule?  Provide a justification for a 
bracketing approach, if applicable. 
 
For dry heat depyrogenation: 
Heat distribution studies: 
  How were locations of thermocouples selected for heat distribution studies, if 
performed? 
  Describe how the cold spots of the load were determined. 
  What were the results of any heat distribution studies performed? 
Heat penetration studies: 
  How were locations of thermocouples and endotoxin-spiked components selected for 
heat penetration studies? 
  What is the source of the endotoxin used?  Was the concentration of endotoxin 
verified?  Was a representative COA for the control standard endotoxin provided to 
Module 3? 
  How was the endotoxin inoculated onto the component, as appropriate?  How was 
recovery performed? 
38  Contains Nonbinding Recommendations 
  What are the acceptance criteria for the qualification of the cycle?  How were these 
developed?  For example: minimum 3 log reduction in endotoxin 
  How were locations for endotoxin-spiked components selected? 
  What were the results of the heat penetration studies? 
 
For depyrogenation by washing, the following information should be included. 
  What loads were used?  Written descriptions of the placement of thermocouples and 
endotoxin-spiked components are useful. 
  What cycle parameters were used for validation and production runs?  For example:  
washing time 
  What type of water is used?  For example:  Water for Injection (WFI) is used for the 
final rinses 
  What is the source of the endotoxin used?  Was the concentration of endotoxin 
verified? Was a representative COA for the control standard endotoxin provided to 
Module 3? 
  How was the endotoxin inoculated onto the component or into the product, as 
appropriate?  How was recovery performed? 
  What are the acceptance criteria for the qualification of the cycle?  How were these 
developed?  For example:  minimum 3 log reduction in endotoxin 
  What is the requalification schedule? 
  Provide a justification for a bracketing approach, if applicable. 
  Provide a justification for the worst-case vial size selected, if applicable. 
 
Are containers / closures sterilized before filling? 
Provide a summary of the thermal qualification and microbiological efficacy of the cycle.  
In addition, provide the validation reports in Module 3.  The qualification information 
typically summarizes cycle parameters, acceptance criteria, loading patterns, monitoring 
locations, sources of biological indicators, results of the studies, and the requalification 
schedules. 
 
Microbiological Monitoring of the Environment 
 
What are the microbiological monitoring programs used in the production areas to 
ensure the quality attributes of the product? 
 
What types of monitoring were performed (for example: non-viable particulate, contact 
plates, anaerobic organisms)?  Were diagrams showing environmental monitoring 
locations provided in Module 3, including room classifications?  What are the alert / action 
limits for each monitoring type and location being monitored?  Describe steps to be taken 
if alert / action limits are exceeded.  What was the frequency of each type of monitoring in 
each room classification?  What media and incubation conditions were used for each type 
of monitoring? 
 
Describe the level of identification of organisms performed for each room 
classification.  Indicate when isolates are identified. 
For example:  to the genus and species level for Class 100 areas. 
39  Contains Nonbinding Recommendations 
 
How is bioburden monitoring performed?  Is the method suitable for its intended use 
and validated?  What are the specifications used? 
Provide a summary here and a copy of the validation report to Module 3.  Provide a copy 
of the method used for bioburden testing if it is not included as a part of the report.  
Identify the volume tested and any dilutions performed.  Describe the number of rinses 
performed and the rinsing agent used if a membrane filtration method is utilized. 
 
Is there a program in place to control bioburden / endotoxin of raw materials used in 
the manufacture of the product? 
If so, provide a description and validation to Module 3, if appropriate. 
 
Process Control Documentation 
 
What documentation ensures process control? 
 
What documentation was provided in support of the sterilization process? 
For example:  evidence of formal written procedures, list of SOPs, copies of the relevant 
SOPs. 
 
Have the sterilization process controls been documented in the batch record? 
The Batch Record should be submitted to the Regional Information Appendix.  Sterilization 
process batch records may include the following information: 
a.  Filling line or filling room. 
b.  The major pieces of sterile production equipment used. 
c.  Holding times. 
d.  If instruction or references to SOPs for sterilization/depyrogenation of 
components are present (or CIP if justified). 
e.  If instructions or references to SOPs for sterilization of the finished product are 
present. 
f.  If instructions for collection of sterility and endotoxin samples are present (how 
many units and how collected). 
g.  If instructions for collecting the bioburden sample and the bioburden limit are 
specified (a SOP may be specified). 
h.  The number of vials or volume of product that is discarded due to filter 
extractable or adsorption (if applicable). 
 
Aseptic processing batch records may include the following additional information: 
i.  Identification of filter (manufacturer and number). 
j.  Maximum pressure for filtration. 
k.  Final filter integrity specifications (e.g., bubble point, wetting agent). 
 
   
40  Contains Nonbinding Recommendations 
V.  STERILE PROCESS VALIDATION QUESTIONS:  TERMINAL MOIST STEAM 
STERILIZATION 
 
Description of the Process and Product 
 
Is this information referenced in a Master File? 
 
Is a letter of authorization for the Master File provided, if necessary? 
Provide letter of authorization to master files, if necessary. 
 
What is the sterilization process?  How was it developed? 
 
For example:  saturated steam. 
 
Identify the autoclave within the facility. 
Provide the location of the autoclave(s) and identify what autoclave is used for the process. 
 
Is this an overkill or bioburden-based cycle? 
Describe any studies that were performed to support the use of the proposed cycle.  This 
may be further explained in the section that describes the quality attributes of the product. 
 
What container / closure system was used during cycle development? 
This should be the container / closure system that is intended for marketing of the product. 
 
Are containers / closures depyrogenated before filling? 
Is depyrogenation done by dry heat or washing?  If depyrogenation is not performed, a 
justification for eliminating this process should be provided. 
 
For dry heat depyrogenation, is an oven or tunnel used? 
 
What cycle parameters were used for validation and production runs?  For example: 
temperature setpoint(s), belt speed. 
 
What are the acceptance criteria for the qualification of the cycle?  How were these 
developed?  For example: 3-log reduction in endotoxin. 
 
What loading patterns were used?  Were diagrams of the various loading patterns 
provided?  Written descriptions and / or diagram showing locations of thermocouples and 
endotoxin-spiked components are useful.  Diagrams of loading patterns may be submitted 
in Module 3. 
 
   
41  Contains Nonbinding Recommendations 
Heat distribution studies: 
  How were locations of thermocouples selected for heat distribution studies, if 
performed? 
  Describe how the cold spots of the load were determined. 
  What were the results of any heat distribution studies performed? 
 
Heat penetration studies: 
  How were locations of thermocouples and endotoxin-spiked components selected for 
heat penetration studies? 
  What is the source of the endotoxin used?  Was the concentration of endotoxin verified?  
Was a representative Certificate of Analysis for the control standard endotoxin 
provided to Module 3? 
  How was the endotoxin inoculated onto the component?  How was recovery 
performed? 
  What are the acceptance criteria for the qualification of the cycle?  How were these 
developed?  For example:  minimum 3 log reduction in endotoxin 
  How were locations for endotoxin-spiked components selected? 
  What were the results of the heat penetration studies? 
 
What is the requalification schedule? 
 
Provide a justification for a bracketing approach, if applicable. 
 
Provide a justification for the worst-case vial size selected, if applicable. 
 
For depyrogenation by washing, the following information should be included. 
 
What loads were used?  Written descriptions of the placement of thermocouples and 
endotoxin-spiked components are useful. 
 
What cycle parameters were used for validation and production runs?  For example: 
washing time 
 
What type of water is used?  For example:  WFI is used for the final rinses 
 
What is the source of the endotoxin used?  Was the concentration of endotoxin verified?  
Was a representative COA for the control standard endotoxin provided to Module 3? 
 
How was the endotoxin inoculated onto the component or into the product, as appropriate?  
How was recovery performed? 
 
What are the acceptance criteria for the qualification of the cycle? How were these 
developed?  For example:  minimum 3 log reduction in endotoxin 
 
What is the revalidation schedule? 
 
42  Contains Nonbinding Recommendations 
Provide a justification for a bracketing approach, if applicable. 
 
Are containers / closures sterilized before filling? 
Provide a summary of the thermal qualification and microbiological efficacy of the cycle. 
In addition, provide the validation reports in Module 3.  The qualification information 
typically summarizes cycle parameters, acceptance criteria, loading patterns, monitoring 
locations, sources of biological indicators, results of the studies, and the requalification 
schedules. 
 
Was the cycle validation performed using a simulated product? 
Describe the simulated product formulation and characteristics as well as a justification 
for the use of a simulated product. 
 
Is a matrix or bracketing approach proposed? 
Provide the justification for the proposed approach. 
 
Is a filtration step used? What is the purpose of this filtration step in your process? 
Is the purpose to clarify the solution or as bioburden reduction? 
 
Do you intend to pursue parametric release for this product?  If so, what are the 
critical parameters to ensure the success of your sterilization process?  Is there a risk 
assessment plan in place (e.g., control strategies of the cycle, risk of product failure, 
prior manufacturing experience and knowledge)? 
Refer to CDER/CVM/CBER GFI:  Submission of Documentation in Applications for 
Parametric Release of Human and Veterinary Drug Products Terminally Sterilized by 
Moist Heat Processes.xvi 
 
What are the quality attributes of the components or product that are impacted by 
the sterilization process? 
For example:  heat labile. 
 
Are there attributes of the product that may influence the terminal sterilization 
process? 
For example:  viscosity, density. 
 
Thermal Qualification of the Cycle 
 
What are the characteristics of the process that demonstrate the thermal 
qualification of the cycle?  How were the critical process parameters selected, 
validated, and monitored? 
 
What cycle parameters were used for validation and production runs? 
For example:  cycle time and temperature setpoint(s). 
43  Contains Nonbinding Recommendations 
 
What are the acceptance criteria for the qualification of the cycle? How were these 
developed? 
For example: F  
0.
 
What loading patterns were used?  Were diagrams of the various loading patterns 
provided? 
Written descriptions and / or photographs showing items in the load as well as locations of 
thermocouples and biological indicators are useful.  This information will aid in the review 
of the information provided in the Microbiological Efficacy of the Cycle section below.  
Diagrams of loading patterns, including locations of thermocouples and biological 
indicators, may be submitted in Module 3. 
 
How were locations of thermocouples selected for heat distribution studies? 
Describe how the cold spots of the load were determined. 
 
What were the results of the heat distribution studies? 
 
Provide a rationale for locations of thermocouples for heat penetration studies. 
 
What were the results of the heat penetration studies?  If this is a new autoclave, was 
representative raw thermocouple data provided in Module 3 for verification of the F  
0
calculation? 
 
What is the requalification schedule? 
How often is requalification performed? Which loads are requalified? 
 
Microbiological Efficacy of the Cycle 
 
What are the process controls to ensure the microbiological efficacy and 
consistency of the cycle?  How were the critical process parameters selected, 
validated, and monitored? 
 
What biological indicators were used? 
For example: species of organism, spore strip or spore suspension. 
 
What is the source of the biological indicator?  How are biological indicators qualified 
(i.e., D-value, spore concentration)?  Was a representative Certificate of Analysis for 
the biological indicator provided in Module 3? 
 
What are the acceptance criteria for the qualification of the cycle?  How were these 
developed? 
For example:  sterility assurance level (SAL) of 10-6. 
44  Contains Nonbinding Recommendations 
Provide a rationale for the locations of the biological indicators for the heat 
penetration studies. 
 
How was the biological indicator inoculated onto the component or into the product, 
as appropriate? 
If direct inoculation is not used, provide justification for use of an alternate method (e.g., 
for biological indicator vials). 
 
What incubation conditions were used for biological indicators? 
 
What were the results of the lethality studies? 
 
What is the requalification schedule? 
 
Microbiological Monitoring of the Environment 
 
What are the microbiological monitoring programs used in the production areas to 
ensure the quality attributes of the product? 
 
What types of monitoring were performed?  For example: non-viable particulate, contact 
plates, anaerobic organisms.  Were diagrams showing environmental monitoring locations 
provided in Module 3, including room classifications?  What are the alert / action limits for 
each monitoring type and location being monitored?  Describe steps to be taken if alert / 
action limits are exceeded.  What was the frequency of each type of monitoring in each 
room classification?  What media and incubation conditions were used for each type of 
monitoring? 
 
Describe the level of identification of organisms performed for each room 
classification. Indicate when isolates are identified. 
For example:  to the genus and species level for Class 100 areas 
 
How is bioburden monitoring performed?  Is the method suitable for its intended use 
and validated?  What are the specifications used? 
Provide a copy of the validation report to Module 3.  Provide a copy of the method used for 
bioburden testing if it is not included as a part of the report.  Identify the volume tested and 
any dilutions performed.  Describe the number of rinses performed and the rinsing agent 
used if a membrane filtration method is utilized. 
 
Is there a program in place to control bioburden / endotoxin of raw materials used in 
the manufacture of the product? 
If so, provide a description and validation to Module 3, if appropriate. 
 
Process Control Documentation 
 
What documentation ensures process control? 
45  Contains Nonbinding Recommendations 
 
What documentation was provided in support of the sterilization process? 
For example:  evidence of formal written procedures, list of SOPs, copies of the relevant 
SOPs 
 
Have the sterilization process controls been documented in the batch record? 
The Batch Record should be submitted to the Regional Information Appendix.  Sterilization 
process batch records may include the following information: 
a.  Filling line or filling room. 
b.  The major pieces of sterile production equipment used 
c.  Holding times. 
d.  If instruction or references to SOPs for sterilization/depyrogenation of 
components are present (or CIP if justified). 
e.  If instructions or references to SOPs for sterilization of the finished product are 
present. 
f.  If instructions for collection of sterility and endotoxin samples are present (how 
many units and how collected). 
g.  If instructions for collecting the bioburden sample and the bioburden limit are 
specified (a SOP may be specified). 
h.  The number of vials or volume of product that is discarded due to filter 
extractable or adsorption (if applicable). 
 
VI.  STERILE PROCESS VALIDATION QUESTIONS:  RADIATION 
STERILIZATION 
 
Description of the Process and Product 
 
Is this information referenced in a master file? 
 
Is a letter of authorization for the master file provided, if necessary? 
Provide letter of authorization to master files, if necessary. 
 
What is the sterilization process?  How was it developed? 
 
Is this an overkill or bioburden-based cycle? 
Describe any studies that were performed to support the use of the proposed cycle and the 
desired sterility assurance level.  This may be further explained in the section that describes 
the quality attributes of the product. 
 
What container / closure system was used during cycle development? 
This should be the container / closure system that is intended for marketing of the product. 
 
   
46  Contains Nonbinding Recommendations 
Are containers / closures depyrogenated before filling? 
Is depyrogenation done by dry heat or washing? 
 
For dry heat depyrogenation, is an oven or tunnel used? 
 
What cycle parameters were used for validation and production runs?  For example: 
temperature setpoint(s), belt speed 
 
What loading patterns were used?  Were diagrams of the various loading patterns 
provided?  Written descriptions and / or diagram showing locations of thermocouples and 
endotoxin-spiked components are useful.  Diagrams of loading patterns may be submitted 
in Module 3. 
 
Heat distribution studies: 
  How were locations of thermocouples selected for heat distribution studies, if 
performed? 
  Describe how the cold spots of the load were determined. 
  What were the results of any heat distribution studies performed? 
 
Heat penetration studies: 
  How were locations of thermocouples and endotoxin-spiked components selected for 
heat penetration studies? 
  What is the source of the endotoxin used?  Was the concentration of endotoxin verified?  
Was a representative Certificate of Analysis for the control standard endotoxin 
provided to Module 3? 
  How was the endotoxin inoculated onto the component?  How was recovery performed? 
  What are the acceptance criteria for the qualification of the cycle?  How were these 
developed?  For example: minimum 3 log reduction in endotoxin 
  How were locations for endotoxin-spiked components selected? 
  What were the results of the heat penetration studies? 
 
What is the requalification schedule? 
 
Provide a justification for a bracketing approach, if applicable. 
 
Provide a justification for the worst-case vial size selected, if applicable. 
For depyrogenation by washing, the following information should be included. 
 
What loads were used?  Written descriptions of the placement of thermocouples and 
endotoxin-spiked components are useful. 
 
What cycle parameters were used for validation and production runs?  For example:  
washing time 
 
What type of water is used? For example:  WFI is used for the final rinses 
 
47  Contains Nonbinding Recommendations 
Are containers / closures sterilized before filling? 
Provide a summary of the thermal qualification and microbiological efficacy of the cycle.  
In addition, provide the validation reports in Module 3.  The qualification information 
typically summarizes cycle parameters, acceptance criteria, loading patterns, monitoring 
locations, sources of biological indicators, results of the studies, and the requalification 
schedules. 
 
Was validation performed using a simulated product? 
Describe the simulated product formulation and characteristics as well as a justification for 
the use of a simulated product. 
 
Is a matrix or bracketing approach proposed? 
Provide the justification for the proposed approach. 
 
Is a filtration step used?  What is the purpose of this filtration step in your process? 
Is the purpose to clarify the solution or as bioburden reduction? 
 
Do you intend to pursue parametric release for this product?  If so, what are the 
critical parameters to ensure the success of your sterilization process?  Is there a risk 
assessment plan in place (e.g., control strategies of the cycle, risk of product failure, 
prior manufacturing experience and knowledge)? 
 
What are the quality attributes of the components or product that are impacted by the 
sterilization process? 
For example:  degradation products, excipient loss, container damage.  Any controls used 
to ensure packaging is adequate following the radiation treatment should be included here. 
 
Are there attributes of the components or product that may influence the radiation 
sterilization process? 
For example:  viscosity, density, polymer type. 
 
Dose Mapping and Validation Studies 
 
What are the characteristics of the process that demonstrate the radiation 
qualification of the cycle?  How were the critical process parameters selected, 
validated, and monitored? 
 
How was an acceptable radiation dose for the load demonstrated? 
 
What radiation dose was used for validation and production runs? 
 
What are the acceptance criteria for the qualification of the cycle?  How were these 
developed? 
 
48  Contains Nonbinding Recommendations 
What loading patterns were used?  Were diagrams of the various loading patterns 
provided? 
Written descriptions and / or photographs showing items in the load as well as locations of 
radiation dosimeters and/or biological indicators are useful.  This information will aid in 
the review of the information provided in the Microbiological Efficacy of the Cycle section 
below.  Diagrams of loading patterns, including dosimeter placement, may be submitted in 
Module 3. 
 
How were locations of dosimeters selected for dose mapping studies? 
Provide a rationale for locations of dosimeters for dose mapping studies. 
 
What were the results of the dose mapping studies? 
If bioburden approach was used, what are results of dose confirmation studies? 
 
What is the requalification schedule? 
How often is requalification performed?  Which loads are requalified?  For bioburden 
approaches, what is the frequency of bioburden audit? 
 
Microbiological Efficacy of the Cycle 
 
What are the process controls to ensure the microbiological efficacy and 
consistency of the radiation treatment?  How were the critical process 
parameters selected, validated, and monitored? 
 
What biological indicators (if any) were used? 
For example:  species of organism, spore strip or spore suspension.  If none, provide a 
rationale. 
 
What is the source of the biological indicator?  How are biological indicators qualified 
(i.e., D-value, spore concentration)?  Was a representative Certificate of Analysis for 
the biological indicator provided in Module 3? 
 
What are the acceptance criteria for the qualification of the cycle?  How were these 
developed? 
For example:  sterility assurance level (SAL) of 10-6. 
 
What incubation conditions were used for biological indicators, as appropriate? 
 
What were the results of the lethality studies? 
 
What is the requalification schedule? 
 
   
49  Contains Nonbinding Recommendations 
Microbiological Monitoring of the Environment 
 
What are the microbiological monitoring programs used in the production 
areas to ensure the quality attributes of the product? 
 
What types of monitoring were performed?  For example:  non-viable particulate, contact 
plates, anaerobic organisms.  Were diagrams showing environmental monitoring locations 
provided in Module 3, including room classifications?  What are the alert / action limits for 
each monitoring type and location being monitored?  Describe steps to be taken if alert / 
action limits are exceeded.  What was the frequency of each type of monitoring in each 
room classification?  What media and incubation conditions were used for each type of 
monitoring? 
 
Describe the level of identification of organisms performed for each room 
classification.  Indicate when isolates are identified. 
For example:  to the genus and species level for Class 100 areas. 
 
How is bioburden monitoring performed?  Is the method suitable for its intended use 
and validated?  What are the specifications used? 
Provide a copy of the validation report to Module 3.  Provide a copy of the method used for 
bioburden testing if it is not included as a part of the report.  Identify the volume tested and 
any dilutions performed.  Describe the number of rinses performed and the rinsing agent 
used if a membrane filtration method is utilized. 
 
Is there a program in place to control bioburden / endotoxin of raw materials used in 
the manufacture of the product? 
If so, provide a description and validation to Module 3, if appropriate. 
 
Process Control Documentation 
 
What documentation ensures process control? 
 
What documentation was provided in support of the sterilization process? 
For example:  evidence of formal written procedures, list of SOPs, copies of the relevant 
SOPs 
 
Have the sterilization process controls been documented in the batch record? 
The Batch Record should be submitted to Module 3.  Sterilization process batch records 
may include the following information: 
 
a.  Filling line or filling room; 
b.  The major pieces of sterile production equipment used; 
c.  Holding times; 
50  Contains Nonbinding Recommendations 
d.  If instruction or references to SOPs for sterilization/depyrogenation of 
components are present (or CIP if justified); 
e.  If instructions or references to SOPs for sterilization of the finished product are 
present; 
f.  If instructions for collection of sterility and endotoxin samples are present (how 
many units and how collected); 
g.  If instructions for collecting the bioburden sample and the bioburden limit are 
specified (a SOP may be specified); or 
h.  The number of vials or volume of product that is discarded due to filter 
extractable or adsorption (if applicable). 
 
VII. STERILE PROCESS VALIDATION QUESTIONS:  MICROBIOLOGICAL 
TESTING CONTROLS AND STABILITY CONSIDERATIONS 
 
The questions in this section are applicable to all sterile products, regardless of the method 
used to sterilize the product. 
 
What test methods are included in the product release and stability testing to 
support the quality attributes (sterility) of the product? 
 
Is endotoxin, sterility, or preservative effectiveness (for multi-use products that dont contain a 
preservative) included in the product release and/or stability testing of the product?  What is the 
schedule for any tests performed as a part of the proposed stability commitment? 
 
Are there product or component characteristics that are impacted by the sterilization 
method that should be monitored (e.g., excipients that are sensitive to the sterilization 
process used)? 
 
Is reprocessing of product or components proposed? 
Provide data to support multiple sterilization cycles of components and/ or product.  This should 
include stability studies for lots manufactured using components and/or product that has 
undergone the maximum number of sterilization cycles.  For aseptically processed products, 
routine reprocessing is generally not acceptable. 
 
Container-Closure Integrity 
 
What method was selected to perform container-closure integrity testing? 
For example:  Dye ingress 
 
How was the method demonstrated to be suitable for its intended use and validated? 
 
   
51  Contains Nonbinding Recommendations 
Is a copy of the validation report provided to the submission? 
Provide a copy of the method used to determine container-closure integrity if it is not 
included as a part of the report. 
How many containers were tested? 
How were the positive and negative controls prepared? 
What were the results of the challenge to the container/closure system? 
If a quantitative method (e.g., Dye Ingress) is used, what is the detection limit? 
 
Preservative Effectiveness 
 
Is testing performed according to USP General Chapter <51> Antimicrobial 
Preservative Effectiveness?xvii 
 
Is a copy of the validation report provided to the submission? 
What concentration(s) of preservative were tested for preservative effectiveness? 
The minimum concentration of preservative shown to be effective will be taken into 
consideration when setting the specifications for shelf life.  For example, if the proposed 
stability specification for the preservative is 90-110%, a batch formulated at 90% of the 
label claim should be demonstrated to maintain preservative effectiveness. 
 
What were the results of the preservative effectiveness testing? 
 
Pyrogen or Endotoxin Testing 
 
Is testing performed according to USP General Chapter <85> Bacterial 
Endotoxins?xviii 
 
Is a copy of the validation report provided to the submission? 
 
What method was selected to perform endotoxin testing? 
For example:  gel clot. 
 
How was the method demonstrated to be suitable for its intended use and validated? 
 
What vendor was selected to provide the lysate?  Was the sensitivity of the lysate 
confirmed? 
 
Is a copy of a representative Certificate of Analysis for the control standard endotoxin 
and the lysate provided to the file? 
 
What calculations were performed to determine MVD, NIC, and routine dilution as 
appropriate? 
An explanation of how the routine dilution was selected may be helpful. 
 
52  Contains Nonbinding Recommendations 
Is a commitment to perform inhibition/enhancement testing on the first three 
production lots provided in the submission? 
This commitment only applies if the stability batches were manufactured at the pilot scale. 
 
If a photometric method is utilized, is the standard curve utilized to perform the 
validation provided in the validation report? 
 
Sterility Testing 
 
Is testing performed according to USP General Chapter <71> Sterility Test?xix 
Was a membrane filter or direct inoculation method selected? 
 
How was the method demonstrated to be suitable for its intended use and validated? 
 
Is a copy of the validation report provided to the submission? 
Provide a copy of the method used to determine sterility testing if it is not included as a 
part of the report. 
Identify if the appropriate number of containers and volume tested from each container has 
been selected based on the batch size and container size as indicated in USP General 
Chapter <51>.xx 
 
Has a description of the bacteriostasis/fungistasis testing been provided to the file? 
The description should include the number of rinses performed and the rinsing agent used 
if a membrane filtration method is utilized. 
 
Microbiological Release and Stability Testing 
 
What tests are included in the product release and stability specifications to support 
the biological/microbiological quality attributes of the product? 
Provide a description of the tests performed at each stability test station which support the 
biological/microbiological quality attributes of the product. 
 
USP General Chapter <1> Injections xxi and CVM  GFI #176/VICH GL39:  
Specifications:  Test Procedures and Acceptance Criteria for New Veterinary Drug 
Substances and New Medicinal Products:  Chemical Substances xxii provide additional 
information regarding the setting of specifications. 
   
53  Contains Nonbinding Recommendations 
ENDNOTES 
                                                 
 
i CDER GFI:  M4Q:  The CTD  Quality (ICH) (August 2001) 
http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/U
CM073280.pdf 
 
ii CDER/CBER GFI:  M4:  The CTD  Quality Questions and Answers/Location Issues (ICH) 
(June 2004) 
http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/u
cm073285.pdf 
 
iii CVM GFI #169:  Drug Substance Chemistry, Manufacturing, and Controls Information 
(August 2010) 
http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/Guidancef
orIndustry/UCM052498.pdf 
 
iv CDER/CBER GFI/ICH Q7:  Good Manufacturing Practice Guidance for Active 
Pharmaceutical Ingredients (September 2016; Revision 1) 
http://www.fda.gov/downloads/drugs/guidancecomplianceregulatoryinformation/guidances/ucm
073497.pdf 
 
v CDER/CBER GFI/ICH Q11:  Development and Manufacture of Drug Substances (November 
2012) 
http://www.fda.gov/downloads/drugs/guidancecomplianceregulatoryinformation/guidances/ucm
261078.pdf 
 
vi CVM GFI #5:  Drug Stability Guidelines (December 2008). 
http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/Guidancef
orIndustry/UCM051556.pdf 
 
vii United States Pharmacopoeia Chapter <660> Containers-Glass.  The United States 
Pharmacopeial Convention, Rockville, MD. 
http://www.usp.org/ 
 
viii United States Pharmacopoeia Chapter <661> Containers-Plastics.  The United States 
Pharmacopeial Convention, Rockville, MD 
http://www.usp.org/ 
 
ix CVM GFI #42:  Animal Drug Manufacturing Guidelines (Revised 1994) 
http://www.fda.gov/AnimalVeterinary/GuidanceComplianceEnforcement/GuidanceforIndustry/u
cm053405.htm 
 
x CVM GFI #176/VICH GL39:  Specifications:  Test Procedures and Acceptance Criteria for 
New Veterinary Drug Substances and New Medicinal Products:  Chemical Substances (June 
2006). 
54  Contains Nonbinding Recommendations 
                                                                                                                                                             
 
http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/Guidancef
orIndustry/UCM052487.pdf 
 
xi CVM GFI #64:  Validation of Analytical Procedures:  Methodology (July 1999). 
http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/Guidancef
orIndustry/UCM052379.pdf 
 
xii CVM GFI #93/VICH GL11(R):  Impurities in New Veterinary Medicinal Products (Revised) 
(November 2007). 
http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/Guidancef
orIndustry/UCM052432.pdf 
 
xiii United States Pharmacopoeia Chapter <661> Containers-Plastics.  The United States 
Pharmacopeial Convention, Rockville, MD 
http://www.usp.org/ 
 
xiv CVM GFI #5:  Drug Stability Guidelines (December 2008). 
http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/Guidancef
orIndustry/UCM051556.pdf 
 
xv United States Pharmacopoeia Chapter <71> Sterility Tests.  The United States Pharmacopeial 
Convention, Rockville, MD. 
http://www.usp.org/ 
 
xvi CDER/CVM/CBER GFI:  Submission of Documentation in Applications for Parametric 
Release of Human and Veterinary Drug Products Terminally Sterilized by Moist Heat Processes 
(February 2010). 
http://www.fda.gov/ucm/groups/fdagov-public/@fdagov-drugs-
gen/documents/document/ucm072180.pdf 
 
xvii United States Pharmacopoeia Chapter <51> Antimicrobial Preservative Effectiveness.  The 
United States Pharmacopeial Convention, Rockville, MD. 
http://www.usp.org/ 
 
xviii United States Pharmacopoeia Chapter <85> Bacterial Endotoxins. The United States 
Pharmacopeial Convention, Rockville, MD. 
http://www.usp.org/ 
 
xix United States Pharmacopoeia Chapter <71> Sterility Tests.  The United States Pharmacopeial 
Convention, Rockville, MD. 
http://www.usp.org/ 
 
xx United States Pharmacopoeia Chapter <51> Antimicrobial Preservative Effectiveness. The 
United States Pharmacopeial Convention, Rockville, MD. 
http://www.usp.org/ 
55  Contains Nonbinding Recommendations 
                                                                                                                                                             
 
xxi United States Pharmacopoeia Chapter <1> Injections. The United States Pharmacopeial 
Convention, Rockville, MD. 
http://www.usp.org/ 
 
xxii CVM GFI #176/VICH GL39:  Specifications:  Test Procedures and Acceptance Criteria for 
New Veterinary Drug Substances and New Medicinal Products:  Chemical Substances (June 
2006). 
http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/Guidancef
orIndustry/UCM052487.pdf 
56