Chemistry, Manufacturing, andControl (CMC) Information for
Human Gene Therapy Investigational
New Drug Applications (INDs)
Draft Guidance for Industry
This guidance document is for comment purposes only.

Submit one set of either electronic or written comments on this draft guidance by the dateprovided in the Federal Register notice announcing the availability of the draft guidance.
Submit electronic comments to https://www.regulations.gov. Submit written comments to theDockets Management Staff (HFA-305), Food and Drug Administration, 5630 Fishers Lane, Rm.
1061, Rockville, MD 20852. You should identify all comments with the docket number listed in
the notice of availability that publishes in the Federal Register.
Additional copies of this guidance are available from the Office of Communication, Outreachand Development (OCOD), 10903 New Hampshire Ave., Bldg. 71, Rm. 3128, Silver Spring,
MD 20993-0002, or by calling 1-800-835-4709 or 240-402-8010, or email ocod@fda.hhs.gov, orfrom the Internet athttps://www.fda.gov/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInformation/Guid
ances/default.htm.
For questions on the content of this guidance, contact OCOD at the phone numbers or email
address listed above.

U.S. Department of Health and Human Services
Food and Drug Administration
Center for Biologics Evaluation and Research
July 2018
Corrected July 2018

Chemistry, Manufacturing, andControl (CMC) Information for
Human Gene Therapy Investigational
New Drug Applications (INDs)
Draft Guidance for Industry
Note: Changes have been made to correct text in the “Chemistry, Manufacturing, and Control(CMC) Information for Human Gene Therapy Investigational New Drug Applications (INDs);
Draft Guidance for Industry” dated July 2018, to correct the text in section V.A.3.b.i:•

Added “Ref. 12” to line 1180•

Inserted “T” to “293” on lines 1183 and 1190

U.S. Department of Health and Human Services
Food and Drug Administration
Center for Biologics Evaluation and Research
July 2018
Corrected July 2018

Contains Nonbinding Recommendations
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Table of Contents
I.

INTRODUCTION............................................................................................................. 1II.

BACKGROUND ............................................................................................................... 2

III.

ADMINISTRATIVE INFORMATION (MODULE 1 OF THE CTD)........................ 3
A.
B.
C.
D.

IV.

Administrative Documents ................................................................................... 3
Labels ..................................................................................................................... 3
Environmental Analysis ....................................................................................... 4
Previously Submitted Information ...................................................................... 4

SUMMARY OF QUALITY INFORMATION (MODULE 2 OF THE CTD) ............ 5
A.
B.
C.
D.

V.

General Information ............................................................................................. 5
Drug Substance and Drug Product ..................................................................... 5
Combination Products .......................................................................................... 6
Product Handling at the Clinical Site ................................................................. 6

MANUFACTURING PROCESS AND CONTROL INFORMATION (MODULE 3
OF THE CTD) ................................................................................................................... 7
A.
1.
2.
3.
4.
5.
6.
7.
B.
1.
2.
3.
4.
5.
6.
7.
8.
C.
1.
2.

VI.

Drug Substance (3.2.S) ......................................................................................... 7
General Information (3.2.S.1) ........................................................................... 7
Drug Substance Manufacture (3.2.S.2) ............................................................. 9
Drug Substance Characterization (3.2.S.3) ..................................................... 26
Control of Drug Substance (3.2.S.4) ............................................................... 28
Reference Standards or Materials (3.2.S.5) .................................................... 35
Container Closure System (3.2.S.6)................................................................ 35
Stability (3.2.S.7) ............................................................................................ 35
Drug Product (3.2.P) ........................................................................................... 36
Drug Product Description and Composition (3.2.P.1) .................................... 36
Pharmaceutical Development (3.2.P.2) .......................................................... 37
Manufacture (3.2.P.3) ..................................................................................... 40
Control of Excipients (3.2.P.4) ....................................................................... 41
Control of Drug Product (3.2.P.5) .................................................................. 42
Reference Standards or Materials (3.2.P.6) .................................................... 47
Container Closure System (3.2.P.7)................................................................ 47
Stability (3.2.P.8) ............................................................................................ 48
Appendices (3.2.A) .............................................................................................. 48
Facilities and Equipment (3.2.A.1) ................................................................. 48
Adventitious Agents Safety Evaluation (3.2.A.2) .......................................... 49

REFERENCES ................................................................................................................ 50i

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Chemistry, Manufacturing, and Control (CMC) Information for
Human Gene Therapy Investigational New Drug Applications(INDs)

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Draft Guidance for Industry
This draft guidance, when finalized, will represent 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 therequirements 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

Human gene therapy seeks to modify or manipulate the expression of a gene or to alter the
biological properties of living cells for therapeutic use. We, the FDA, are providing you,sponsors of a human gene therapy Investigational New Drug Application (IND),
recommendations regarding chemistry, manufacturing, and control (CMC) information to besubmitted in an IND. The purpose of this draft guidance is to inform sponsors how to provide
sufficient CMC information required to assure product safety, identity, quality, purity, andstrength (including potency) of the investigational product (21 CFR 312.23(a)(7)(i)). This
guidance applies to human gene therapy products and to combination products 1 that contain ahuman gene therapy in combination with a drug or device.
This draft guidance, when finalized, will supersede the document entitled “Guidance for FDA
Reviewers and Sponsors: Content and Review of Chemistry, Manufacturing, and Control(CMC) Information for Human Gene Therapy Investigational New Drug Applications (INDs),”
dated April 2008 (April 2008 guidance) (Ref. 1). The field of gene therapy has progressed
rapidly since we issued the April 2008 guidance. Therefore, we are updating that guidance toprovide you with current FDA recommendations regarding the CMC content of a gene therapy
IND. This guidance is organized to follow the structure of the FDA guidance on the Common
Technical Document (CTD). Information on the CTD can be found in the “Guidance forIndustry: M4Q: The CTD – Quality,” dated August 2001 (Ref. 2). For information on thesubmission of an electronic CTD (eCTD), please see the FDA website
https://www.fda.gov/Drugs/DevelopmentApprovalProcess/FormsSubmissionRequirements/ElectronicSubmissions/ucm153574.htm.
1

Combination products are comprised of any combination of a drug and a device; a device and a biological product;a biological product and a drug; or a drug, a device, and a biological product; see 21 CFR 3.2(e) for the complete
definition of combination product. Combination products are assigned to a lead center for review; see 21 CFR 3.4.

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FDA’s guidance documents, including this guidance, do not establish legally enforceable
responsibilities. Instead, guidance describes the FDA’s current thinking on a topic and should beviewed only as recommendations unless specific regulatory or statutory requirements are cited.
The use of the word should in FDA’s guidance means that something is suggested orrecommended but not required.

II.

BACKGROUND

Human gene therapy products are defined as all products that mediate their effects bytranscription or translation of transferred genetic material or by specifically altering host (human)
genetic sequences. Some examples of gene therapy products include nucleic acids, geneticallymodified microorganisms (e.g., viruses, bacteria, fungi), engineered site-specific nucleases used
for human genome editing, 2 and ex vivo genetically modified human cells. Gene therapy
products meet the definition of “biological product” in section 351(i) of the Public HealthService (PHS) Act (42 U.S.C. 262(i)) when such products are applicable to the prevention,
treatment, or cure of a disease or condition of human beings.
The FDA requires all sponsors of investigational new drug products (DPs), including
investigational gene therapy products, to describe the CMC information for the drug substance(DS) (21 CFR 312.23(a)(7)(iv)(a)) and the DP (21 CFR 312.23(a)(7)(iv)(b)). FDA may place
the IND on clinical hold if the IND does not contain sufficient CMC information to assess therisks to subjects in the proposed studies (21 CFR 312.42(b)(1)(iv)).
The CMC information submitted in an IND is a commitment to perform manufacturing andtesting of the investigational product, as stated. We acknowledge that manufacturing changes
may be necessary as product development proceeds, and you should submit information
amendments to supplement the initial information submitted for the CMC processes (21 CFR
312.23(a)(7)(iii)). The CMC information submitted in the original IND for a Phase 1 study may
be limited, and therefore, the effect of manufacturing changes, even minor changes, on productsafety and quality may not be known. Thus, if a manufacturing change could affect productsafety, identity, quality, purity, potency, or stability, you should submit the manufacturingchange prior to implementation (21 CFR 312.23(a)(7)(iii)).
We recently published a guidance document, entitled “Providing Regulatory Submissions inElectronic Format – Certain Human Pharmaceutical Product Applications and Related
Submissions Using the eCTD Specifications; Guidance for Industry,” dated April 2017,
addressing the electronic submission of certain applications in the CTD format (eCTD) (Ref. 3).
Beginning May 5, 2017, all New Drug Applications (NDAs), Abbreviated New Drug
Applications (ANDAs), Biologics License Applications (BLAs), and Master Files must be
submitted in eCTD, and commercial IND submissions must be submitted in eCTD, beginning2

Human Genome Editing: Science, Ethics, and Governance. The National Academies Press; 2017.
https://www.nap.edu/read/24623/chapter/1#xvii

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May 5, 2018 (Ref. 3). Excluded from the eCTD requirement are INDs for devices under section
351 of the PHS Act and products that are not intended to be distributed commercially.
Investigator-sponsored INDs and expanded access INDs (e.g., emergency use INDs andtreatment INDs) are also excluded from the eCTD requirement. In preparation for meeting theserequirements, we recommend that sponsors begin to organize and categorize their CMC
information, according to the CTD format.
You are not required to complete all CTD sections in your original IND submission. The
amount of CMC information to be submitted in your IND depends on the phase of investigation(21 CFR 312.23(a)(7)(i)) and the scope of the clinical investigation proposed. The emphasis for
CMC review in all phases of development is product safety and manufacturing control. We
expect that sponsors may need to make modifications to previously submitted information asclinical development proceeds and additional product knowledge and manufacturing experience
is collected.
We are providing detailed recommendations for submitting CMC information in Module 3 ofyour IND. We have structured these recommendations to follow the outline of the FDA“Guidance for Industry: M4Q: The CTD – Quality,” dated August 2001 (Ref. 2). We are also
providing general recommendations regarding administrative and quality summary information
for Modules 1 and 2, respectively, of the CTD structure.

III.

ADMINISTRATIVE INFORMATION (MODULE 1 OF THE CTD)
A.

Administrative Documents

Administrative documents (e.g., application forms, such as Form FDA 1571, cover
letters, reviewer guides, and cross-reference authorization letters), claims of categoricalexclusion, and labeling information should be included in Module 1 of CTD submissions.
The cover letter of your submission should include a brief explanation of yoursubmission and its contents. When amendments are submitted to the IND for
manufacturing changes, your cover letter should clearly describe the purpose of theamendment and highlight proposed changes. For amendments containing numerous orsignificant changes, we recommend that you include a “Reviewer’s Guide,” as describedin FDA’s “eCTD Technical Conformance Guide: Technical Specifications Document,”
dated November 2017 (Ref. 4), and that you allow sufficient lead time (e.g., 30 days) for
FDA review before release of a new lot of clinical trial material.
B.

LabelsYour IND must contain a copy of all labels and labeling to be provided to each
investigator in the clinical study (21 CFR 312.23(a)(7)(iv)(d)). We recommend that you
include sample labels in Module 1 of the CTD. Please note that IND products must beara label with the statement, “Caution: New Drug--Limited by Federal (or United States)
law to investigational use” (21 CFR 312.6). For products derived from autologous

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donors and other situations described in 21 CFR 1271.90(a) for which a donor eligibility
determination is not required, you must include the required labeling in
21 CFR 1271.90(c), as applicable. For example, for cells intended for autologous use,
you must label the product “FOR AUTOLOGOUS USE ONLY” (21 CFR 1271.90(c)(1))
and “NOT EVALUATED FOR INFECTIOUS SUBSTANCES” if donor testing andscreening is not performed (21 CFR 1271.90(c)(2)).
C.

Environmental Analysis

Your IND must contain either an environmental analysis or a claim for categoricalexclusion (21 CFR 312.23(a)(7)(iv)(e)). Please note that, under ordinary circumstances,most INDs are eligible for categorical exclusion under 21 CFR 25.31(e) (Ref. 5). This
information can be submitted in Module 1 of the CTD.
D.

Previously Submitted Information

For INDs, you generally are not required to resubmit information that you havepreviously submitted to the Agency, and you may incorporate such information byreference. You may submit a written statement in your IND that appropriately identifies
previously submitted information (21 CFR 312.23(b)). We recommend you describe theinformation that you are referencing and identify where that information is located in thepreviously submitted file.
You may also reference information previously submitted by another individual if proper
authorization has been granted. Proper authorization may be granted with a Letter ofAuthorization (LOA) from the individual who submitted the information(21 CFR 312.23(b)). We recommend that the LOA include a description of theinformation being cross-referenced (e.g., reagent, container, vector manufacturing
process) and identify where that information is located (e.g., file name, reference number,volume, page number). Please note that this LOA only allows you to cross-reference theinformation outlined in the LOA and submitted by the author of the LOA. The LOA
does not provide you permission to cross-reference information that was submitted byanother individual and cross-referenced by the author of the LOA. In other words, you
may not cross-reference information that is cross-referenced by the author of the LOA.
You are required to submit an LOA for all information submitted by another individual(21 CFR 312.23(b)).
In addition to including LOAs in Module 1 of the CTD, you should list these files in the
IND cover sheet (i.e., Form FDA 1571) of each IND submission. If the LOA is absent orinadequate or the information in the cross-referenced file is inadequate for the purpose
cited, we will notify you that the information in the cross-referenced file is not sufficient
to support your IND. In the event a cross-referenced IND is placed on clinical hold or iswithdrawn, your IND may also be placed on clinical hold if critical cross-referenced
information is no longer available or adequate.

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IV.

SUMMARY OF QUALITY INFORMATION (MODULE 2 OF THE CTD)A.

General Information

Your IND should contain a general introduction to the gene therapy product underinvestigation, including a description of its active ingredient(s), mode of action, andproposed clinical use. This summary should include an overview of the manufacturing
process, controls in place to ensure product quality, and general information regarding thequalification of components and starting materials. You should describe the compositionof the DS and DP. You should indicate if the DS is formulated into a DP for
administration or if the DS is used for ex vivo genetic modification of cells.
Your summary should also include a description of critical quality attributes (CQAs) thatare relevant to the safety and biological activity of the product as they are understood at
the time of submission. For additional information regarding establishing CQAs, please
see Guidance for Industry: “Q8(R2) Pharmaceutical Development,” dated November
2009 (Ref. 6), and “Q11 Development and Manufacture of Drug Substances,” dated
November 2012 (Ref. 7). A CQA is defined as a physical, chemical, biological, or
microbiological property or characteristic that should be within an appropriate limit,
range, or distribution to ensure the desired product quality. CQAs apply to DS and DP as
well as to excipients and in-process materials. Information to support a CQA and resultsfrom specific studies or published literature may be included in Module 3 of the CTD“Pharmaceutical Development” (section 3.2.P.2) (Ref. 2) or linked to the relevant
nonclinical or clinical sections of the application in the CTD.
As product development progresses, CQAs may be used to define DS and DP
specifications. Understanding and defining product characteristics that are relevant to theclinical performance of the gene therapy may be challenging, particularly during earlystages of product development. Therefore, we recommend that you evaluate a number of
product characteristics during early clinical development to help you identify andunderstand the CQAs of your product. This will also help ensure your ability to assess
manufacturing process controls, manufacturing consistency, and product stability as
product development advances. This is especially important for sponsors of gene therapy
products who are pursuing expedited product development programs (Ref. 8).
B.

Drug Substance and Drug ProductYour IND must contain a description of the DS (21 CFR 312.23(a)(7)(iv)(a)) and DP(21 CFR 312.23(a)(7)(iv)(b)), including the physical, chemical, or biologicalcharacteristics, manufacturing controls, and testing information, to ensure the DS and DP
meet acceptable limits for identity, strength (potency), quality, and purity. For the
purpose of this guidance, a DS is defined as an active ingredient that is intended tofurnish biological activity or other direct effect in the diagnosis, cure, mitigation,

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treatment, or prevention of disease or to affect the structure or any function of the humanbody. Further, a DP is defined as the finished dosage form that contains the DS,
generally, but not necessarily in association with one or more other ingredients (e.g.,
excipients).
We recognize that distinguishing a DS from a DP may be difficult for some gene therapy
products, due to the complex nature of the manufacturing processes. Some gene therapy
products may not have defined DS. Others may consist of two or more different DSs thatare combined to make the DP. This guidance does not recommend how sponsors should
distinguish the DS and DP. However, we do recommend that you provide an explanation
to support your DS/DP distinction in the summary information in Module 2 of CTD
submissions and that you submit the required information for each DS and DP, as
outlined in Module 3 of the CTD (Ref. 2).
When the manufacturing process includes more than one DS, we recommend that you
provide separate DS sections for each active ingredient of the final product. The CTD
DS sections should follow the format and numbering scheme recommended in Module 3of FDA “Guidance for Industry: M4Q: The CTD – Quality,” dated August 2001 (Ref.
2), and the sections should be distinguished from one another by including the DS nameand manufacturer in the heading (e.g., section 3.2.S.1 General Information [name,manufacturer]).
A summary of the available stability data for the DS and the DP, recommended storage
conditions, and tentative expiry date, if applicable, should also be included in this section.
Information on stability protocols and stability data should be included in the appropriate
sections of Module 3.
C.

Combination Products

For submissions in which the gene therapy is a component of a combination product, as
defined in 21 CFR 3.2(e), we recommend that you briefly describe the combination
product in the summary of your product and briefly state the regulatory status of eachcomponent. To clearly delineate the different components of a combination product, you
should include manufacturing and engineering information for the gene therapy and drugor device in separate entries of the CTD submission, as described in the FDA “eCTD
Technical Conformance Guide: Technical Specifications Document,” dated November
2017 (Ref. 4).
D.

Product Handling at the Clinical Site

Proper control of the finished DP is critical to your investigational studies. Therefore,
your IND should also include a description of how the product will be shipped to,received, and handled at the clinical site to ensure safety, product quality, and stability.
Your IND should also include information on shipping conditions, storage conditions,expiration date/time (if applicable), and chain of custody from the manufacturer to the6Contains Nonbinding Recommendations
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site of administration in the summary information of the CTD. Your summary in Module
2 should also include information for product handling at the clinical site prior toadministration (such as thawing, washing, or the addition of diluent or adjuvant, loading
into a delivery device, and transport to the bedside) and summary information on productstability prior to and during administration (e.g., in-device hold times and temperatures).
Details regarding product stability after preparation for delivery and delivery devicecompatibility data should be included in Module 3 (sections 3.2.P.8 and 3.2.P.2.6,
respectively) of the CTD (Ref. 2). Instructions for drug handing and preparation foradministration at the clinical site (e.g., Pharmacy Manual or Instructions for Use) should
be provided in the “Clinical Study Reports” section of your IND (section 5.3 of the FDA“M4E(R2): The CTD – Efficacy; Guidance for Industry,” dated July 2017 (Ref. 9)).
Detailed information about the delivery device may be included in “Regional
Information” (section 3.2.R of the CTD) (Ref. 2).

V.

MANUFACTURING PROCESS AND CONTROL INFORMATION (MODULE 3
OF THE CTD)

The headings and text below include CTD section numbers in parentheses for reference (Ref. 2).
A.

Drug Substance (3.2.S)
1.

General Information (3.2.S.1)
a.

Nomenclature (3.2.S.1.1)

You should provide the name of the DS(s). If the name of the DS haschanged during clinical development, you should provide the names used
to identify the DS at all stages of development. If the United States
Adopted Name (USAN) Council has given it a nonproprietary name, you
may provide it here.
b.

Structure (3.2.S.1.2)

You should submit information on the molecular structure (including
genetic sequence) and/or cellular components of the DS. The genetic
sequence can be represented in a schematic diagram that includes a map ofrelevant regulatory elements (e.g., promoter/enhancer, introns, poly(A)signal), restriction enzyme sites, and functional components (e.g.,transgene, selection markers). Please note that you should also submit
information on your sequence analysis and the annotated sequence data inyour IND. We recommend that your sequence data, including any datacollected to support the genetic stability of your vector, be submitted in“Elucidation of Structure and other Characteristics” (section 3.2.S.3.1 of7

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the CTD). More information on our recommendations for sequence
analysis is described in “Control of Materials (3.2.S.2.3)” (section
V.A.2.c. of this guidance).
Some examples of additional information for structure and structuralelements of different gene therapy products are outlined below:c.

•

For viral vectors, you should include a description of thecomposition of the viral capsid and envelope structures, as
appropriate, and any modifications to these structures (e.g.,modifications to antibody binding sites or tropism-changing
elements). We recommend that you include biophysicalcharacteristics (e.g., molecular weight, particle size) andbiochemical characteristics (e.g., glycosylation sites). You should
also describe the nature of the genome of viral vectors, whether
single-stranded, double-stranded, or self-complementary, DNA orRNA, and copy number of genomes per particle.

•

For bacterial vectors, you should include defining physical andbiochemical properties, growth characteristics, genetic markers(e.g., auxotrophic or attenuating mutations, antibiotic resistance)
and the location (e.g., on plasmid, episome, or chromosome) anddescription of any inserted foreign genes and regulatory elements.
For additional details on microbial vectors, please see the FDA’s
Guidance for Industry “Recommendations for Microbial Vectors
used for Gene Therapy,” dated September 2016 (Ref. 10).

•For ex vivo genetically modified cells, you should describe theexpected major and minor cell populations as well as the vector
that contains the transgene cassette that is transferred into the cell.
For cells that have been genetically modified using genome
editing, you should describe the gene(s) that are altered and how
the change(s) was made (i.e., the gene editing technology used).
General Properties (3.2.S.1.3)

You should provide a section in the IND that describes the compositionand properties of the DS, including the biological activity and proposedmechanisms of action.

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2.

Drug Substance Manufacture (3.2.S.2)
a.

Manufacturer(s) (3.2.S.2.1)

You must provide the name and address of each manufacturer, including
contract manufacturer(s), involved in the manufacture, testing, and storageof the DS (21 CFR 312.23(a)(7)(iv)(a)). You should indicate theresponsibility of each manufacturer. Your IND should contain complete
information on the DS manufacturer, regardless of whether the process isperformed by you or by a contract manufacturing organization (CMO).
As the sponsor of the IND, you are ultimately responsible for the safety ofsubjects in the clinical investigation (21 CFR 312.3); therefore, we
recommend that you and the CMO understand and document yourrespective responsibilities for ensuring product quality. Additional
information on quality agreements can be found in FDA’s Guidance forIndustry, “Contract Manufacturing Arrangements for Drugs: Quality
Agreements,” dated November 2016 (Ref. 11).
b.

Description of Manufacturing Process and Process Controls(3.2.S.2.2)

Your description of the DS manufacturing process and process controls
should include all of the following, as applicable: cell culture;transduction; cell expansion; harvest(s); purification; filling; and storage
and shipping conditions. Your description should also accurately
represent your process and process controls. Changes and updates to thisinformation should be submitted as an amendment to the IND prior to
implementation (21 CFR 312.23(a)(7)(iii)), as indicated in section II.
Background of this guidance.
i.

Batch and Scale

A description of how you define each manufacturing run (i.e.,batch, lot, other) should be submitted with an explanation of thebatch (or lot 3) numbering system. You should clearly state
whether any pooling of harvests or intermediates occurs during
manufacturing. If pooling is necessary during production, we
recommend that you control the storage conditions (e.g., time,
temperature, container) for each pool and that you describe thetesting that is performed prior to pooling to ensure the quality ofeach pool.

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We also recommend that you provide an explanation for how thebatch scale is defined (e.g., bioreactor volume, cell processing
capacity) and how the DS is quantified (e.g., vector genomes,transducing units, infectious particles, mass, number of genemodified cells). When known, please include the yield expected
per batch.
ii.

Manufacturing Process

The description of your manufacturing process should include aflow diagram(s) and a detailed narrative. Your description should
clearly identify any process controls and in-process testing (e.g.,titer, bioburden, viability, impurities) as well as acceptable
operating parameters (e.g., process times, temperature ranges, cellpassage number, pH, CO2, dissolved O2, glucose level).
We recommend the evaluation of operating parameters on aperiodic basis to ensure process control and allow for trending andstatistical analyses if deemed appropriate to monitor process
consistency. You should clearly describe any environmental
controls as well as tracking and segregation procedures that are inplace to prevent cross-contamination throughout the manufacturing
process.
iii.

Cell Culture

The description of all cell culture conditions should containsufficient detail to make understandable any of the process steps
that apply, process timing, culture conditions, hold times andtransfer steps, and materials used (e.g., media components,
bags/flasks). You should describe whether the cell culture systemis open or closed and any aseptic processing steps. If extensive
culture times are needed, you should outline the in-process controls
you have in place to monitor cell quality (e.g., viability, bioburden,pH, dissolved O2). Expectations for media components and cellbank qualification are outlined in this guidance under “Control ofMaterials (3.2.S.2.3)” (section V.A.2.c. of this guidance).
iv.

Vector Production

For the manufacture of gene therapy vectors (e.g., viral vectors,
bacterial plasmids, mRNA), you should provide a description of all
production and purification procedures. Production proceduresshould include a description of the cell substrate, cell culture andexpansion steps, transfection or infection procedures, harvest steps,

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hold times, vector purification (e.g., centrifugation, column
purification, density gradients), concentration or buffer exchange
steps, and the reagents/components used during these processes.
You should outline any in-process testing to ensure vector quality
as appropriate (e.g., titer, impurities).
You should describe whether the DS will be formulated into the
DP for direct administration or whether it will be formulated for exvivo genetic modification of cells, as outlined in section IV.B. As
an active ingredient, the same level of control should be applied toeach DS, and each DS should be manufactured under appropriate
Good Manufacturing Practice (GMP) conditions. For more
information on your Quality Unit and GMP manufacturing, see“Process Validation and/or Evaluation (3.2.S.2.5)” (section
V.A.2.e. of this guidance).
v.

Genetically Modified Cell Production

If your product consists of genetically modified cells, your cellprocessing description should contain sufficient detail to makeunderstandable any of the following process steps that apply:
source material (e.g., autologous or allogeneic cells); collection ofcellular source material (e.g., leukapheresis, biopsy); storage at thecollection site; shipping to and handling at the manufacturing
facility; cell selection, isolation, or enrichment steps (including
methods, devices, reagents); cell expansion conditions; hold times
and transfer steps; and cell harvest, purification, if any, andmaterials used.
You should also provide a complete description of all procedures
used for gene modification (such as transfection, infection orelectroporation of vectors, or genome editing components) and any
additional culture, cell selection, or treatments after modification.
vi.

Irradiated Cells

If your product contains or is processed with irradiated cells, you
should provide documentation for the calibration of the irradiatorsource and provide supporting data to demonstrate that theirradiated cells are rendered replication-incompetent, while still
maintaining their desired characteristics.

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vii.

Filling, Storage, and Transportation (Shipping)

You should provide a detailed description and identify any
associated process controls for formulation, filling, storage, andshipping of the DS, if applicable. You should also describe thecontainer used for storage and shipping of the DS. We recommendthat you describe procedures that are in place to ensure appropriate
storage and transport (as needed).
c.

Control of Materials (3.2.S.2.3)

You must provide a list of all materials used in manufacturing(21 CFR 312.23(a)(7)(iv)(b)) and a description of the quality and controlof these materials. This information may be provided in tabular format
and include the identity of the material, the supplier, the quality (e.g.,clinical-grade, FDA-approved), the source of material (e.g., animal,
human, insect), and the stage at which each material is used in the
manufacturing process (e.g., culture media, vector purification). This
includes information on components, such as cells, cell and viral banking
systems, and reagents, as described in more detail below; it also includes
raw materials and equipment, such as culture bags, culture flasks,
chromatography matrices, and tubing, that come into contact with the
product.
You should provide documentation that the materials used for
manufacturing meet standards appropriate for their intended use (e.g., test
results, certificates of analysis (COAs), package inserts). COAs formaterials can be provided in “Facilities and Equipment” (section 3.2.A.1of the CTD) and hyperlinked to relevant sections of your IND. We
recommend that you use FDA-approved or cleared or other clinical-grade
materials, when they are available. If the material is not FDA-approved or
cleared (or in the absence of recognized standards), additional informationon the manufacturing and/or testing may be needed to evaluate the safety
and quality of the material. The extent of testing will depend on thespecific material and the manner in which it is used in the manufacturing
process.
i.

Reagents

For purpose of this guidance, reagents (or ancillary materials) arethose materials used for manufacturing (e.g., cell growth,differentiation, selection, purification, or other criticalmanufacturing steps) that are not intended to be part of the final
product. Examples include fetal bovine serum, digestive enzymes(e.g., trypsin, collagenase, DNase/RNase, restriction

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endonucleases), growth factors, cytokines, monoclonal antibodies,
antibody-coated beads, antibiotics, media, media components, anddetergents. These reagents can affect the safety, potency, andpurity of the final product, especially by introducing adventitious
agents or other impurities.
For biologically sourced reagents, including human, bovine, andporcine-derived materials, we recommend that you refer to the
FDA Guidance for Industry: “Characterization and Qualificationof Cell Substrates and Other Biological Materials Used in the
Production of Viral Vaccines for Infectious Disease Indications,”
dated February 2010 (Ref. 12). Animal-derived materials increase
the risk of introducing adventitious agents. Certain animal-derived
materials, such as sera, are complex mixtures that are difficult tostandardize, and such materials may have significant batch-tobatch variations that may affect the reproducibility of yourmanufacturing process or the quality of your final product. We
recommend that you use non-animal-derived reagents wheneverpossible (for example, serum-free tissue culture media andrecombinant proteases).
ii.

BovineWe recommend that you provide information on any bovine
material used in manufacturing, including the source of thematerial; information on the location where the herd was born,raised, and slaughtered; and any other information relevant to therisk of transmissible spongiform encephalopathy (TSE). If serum
is used, we recommend that it be γ-irradiated to reduce the risk ofadventitious agents.
Bovine materials used in production of reagents, which are, in turn,used in manufacturing a product, should also be identified, and thesource and qualification of bovine material should be documented.
You should provide COAs for all bovine material lots used in the
manufacture and establishment of cell and virus banks to documentthat these materials are compliant with the requirements for the
ingredients of animal origin used for production of biologics
described in 9 CFR 113.53.

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iii.

PorcineYou should provide COAs for all porcine material lots used in
manufacture and establishment of cell and virus banks to documentthat these materials are compliant with the requirements for the
ingredients of animal origin used for production of biologics
described in 9 CFR 113.53. In addition, porcine reagents shouldbe tested for porcine circovirus (PCV) 1 and 2 and porcine
parvovirus.
iv.

Murine or Monoclonal Antibodies

Monoclonal antibodies used in manufacturing that have productcontact should be tested as per the recommendations described in
the FDA “Points to Consider in the Manufacture and Testing of
Monoclonal Antibody Products for Human Use,” dated February
1997 (Ref. 13). Alternatively, you may provide a letter ofauthorization to cross-reference this information in a different
regulatory submission (IND or MF). You should also consider thatmany monoclonal antibodies and recombinant proteins (such as
cytokines) used during the manufacture of gene therapy products
may be purified by affinity chromatography, using antibodies
generated from mouse hybridomas. This may introduce the risk ofcontamination with adventitious agents from rodents.
v.

Human Source

If human albumin is used, you should use FDA-approved products
and have procedures in place to ensure that no recalled lots wereused during manufacture or preparation of the product.
If human AB serum is used (e.g., for ex vivo genetically modified
cells), you should ensure the serum is processed from blood orplasma collected at FDA licensed facilities. Source Plasma, which
is often used to make human AB serum, must be collected as
described in 21 CFR Part 640, Subpart G. Source Plasma is nottested as extensively as blood products intended for infusion, andwe recommend that you ensure the AB serum used in yourmanufacturing does not have the potential to transmit infectious
disease. For example, if your serum is derived from Source
Plasma, you may reduce the risk of infectious disease by
conducting additional testing for relevant transfusion-transmitted
infections. Alternatively, including viral inactivation or clearance
steps in the production of AB serum from Source Plasma may bean acceptable alternative.

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For all other reagents that are human-derived, you should identify
whether the reagent is a licensed product (e.g., HSA, IL-2) or isclinical or research grade and provide a COA or information
regarding testing of the donor or reagent.
vi.

Cells - Autologous and Allogeneic Cells or Tissue

For autologous or allogeneic cells or tissue, you should provide a
detailed description of the cell source, the collection procedure,
and any related handling, culturing, storage, and testing that is
performed prior to use in manufacture. Your description should
include the following information:•materials used for collection (including devices, reagents,
tubing, and containers);•

method of cell collection (i.e., standard blood draw orapheresis);•enrichment steps, if performed;•

labeling and tracking of collected samples;•

hold times; and•transportation conditions to the manufacturing facility.

As an example, for cells collected by leukapheresis: you should
provide a detailed description of the collection device(s); operating
parameters; volumes or number of cells to be collected; and how
the collected material is labeled, stored, tracked, and transported tothe manufacturing facility.
For multi-center clinical trials, establishing standardized
procedures for cell collection and handling across all collection
sites is critical to assuring the quality and safety of the final
product as well as ensuring control of the manufacturing process.
In your IND, you should include a list of collection sites, their
FDA Establishment Identifier, and any accreditations forcompliance with established standards (e.g., Foundation for the
Accreditation of Cellular Therapy (FACT)), if applicable.

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A.

Autologous Cells

You are not required to make a donor eligibility
determination or to perform donor screening on autologous
cells or tissues (21 CFR 1271.90(a)(1)). However, you
should determine whether your manufacturing procedures
increase the risk to the patient by further propagation ofpathogenic agents that may be present in the donor. You
should also describe precautions to prevent the spread ofviruses or other adventitious agents to persons other than
the autologous recipient (Ref. 14).
B.

Allogeneic Cells

For allogeneic cells or tissues, you must perform donor
screening and testing, as required in 21 CFR Part 1271,
Subpart C, except for those cells and tissues that meet the
exceptions in 21 CFR 1271.90(a). Donors of all types ofcells and tissues must be screened for risk factors andclinical evidence of relevant communicable disease agentsand diseases, including: human immunodeficiency virus(HIV); hepatitis B virus (HBV); hepatitis C virus (HCV);
human TSE, including Creutzfeldt-Jakob disease; andTreponema pallidum (syphilis) (21 CFR 1271.75). In
addition, donors of viable leukocyte-rich cells or tissues
should be screened for human T-lymphotropic virus(HTLV). You must also test a specimen of donor cells or
tissue for evidence of infection due to relevant
communicable disease agents, including: HIV-1; HIV-2;
HBV; HCV; syphilis; and if the material is leukocyte-richcells or tissue, HTLV-1, HTLV-2, and cytomegalovirus (21CFR 1271.85). For donor eligibility testing, you must use
appropriate FDA-licensed, approved, or cleared donor
screening tests (21 CFR 1271.80(c)). You should also referto recent Center for Biologics Evaluation and Research(CBER) guidance documents on donor eligibility for
additional information on testing for emerging relevant
communicable disease agents and diseases (e.g., West Nilevirus (WNV), Zika virus). If cord blood or othermaternally-derived tissue is used, you must perform
screening and testing on the birth mothers, as described in
21 CFR 1271.80(a).

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Allogeneic cells from a single donor or source tissue may
sometimes be expanded and stored for greater consistency
and control in manufacturing. In these situations, we
generally recommend that you qualify allogeneic masterand working cell banks in the same way as cell banks used
for production of viral vectors (see “Banking Systems,”
below), provided that you have sufficient material for thistesting. In these situations, we are most concerned about
the introduction of adventitious agents (e.g., viruses,bacteria, mycoplasma) during the bank manufacturing
process, especially from any bovine or porcine materials,
animal feeder cells, other animal-derived reagents, orhuman AB serum, if used. If your allogeneic cell bank issmall, we may recommend abbreviated cell bankqualification. In this case, please consult with the Quality
Reviewer of your file for more information on appropriatequalification of small scale allogeneic cell banks.
vii.

Banking Systems (Starting Materials)

A banking system improves control and consistency in the
manufacturing of many biologics. Banking assures an adequate
supply of equivalent, well-characterized material for production
over the expected lifetime of production. For these reasons,banked materials are a common starting point for many routine
production applications. We outline our current thinking for thequalification of different banking systems below, including banksof cell substrates for production of viral vectors, banks ofbacterial/microbial cells, and banks of viral vectors. We
recommend that you provide a summary of the testing and COAs
in this section. Information on bank qualification and adventitious
agent testing should also be included in your comprehensive“Adventitious Agents Safety Evaluation” (section 3.2.A.2 of the
CTD).
viii.

Master Cell Banks Used as Substrates for Production ofViral Vectors

Prior to selecting a cell line for viral vector manufacturing, you
should carefully consider characteristics of the cells that may
impact the safety of the final product (such as presence oftumorigenic sequences). This is especially important when theviral vector co-packages non-vector sequences, such as adenoassociated virus (AAV) (see “Impurities (3.2.S.3.2)” section
V.A.3.b. of this guidance). We also recommend that you consider

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cell attributes that can affect production capacity (e.g., growth
characteristics, vector production capacity), prior to generation of acell bank.
In your IND, you should provide a description of the history anddetailed derivation of the source material for the cell bank. Your
description should include information on cell source (including
species of origin); how the bank was generated (e.g., from a single
colony isolate or through limiting dilution); testing performed tocharacterize the bank; and if applicable, materials used togenetically modify the source material (i.e., packaging cell line).
When a cell substrate has been genetically modified (for example,
to provide viral proteins to allow virus replication or packaging),
you should provide a description of the materials used for the
genetic modification, including information on the quality andcontrol of the vectors used to introduce the genetic changes.
Materials used to manufacture process intermediates should be
sufficiently characterized to ensure safety and purity of the final
gene therapy product. For more information regarding plasmidintermediates that are used for further manufacture, please see“Control of Critical Steps and Intermediates (3.2.S.2.4)” (section
V.A.2.d. of this guidance).
For the banked material, itself, we recommend that you provide
information on how the cell banks are stored and maintained aswell as detailed information on qualification to adequately
establish the safety, identity, purity, and stability of the cells usedin your manufacturing process. Additional sources of information
regarding qualification of cell substrates can be found in the FDA
guidance “Q5D Quality of Biotechnological/Biological Products:
Derivation and Characterization of Cell Substrates Used for
Production of Biotechnological/Biological Products” (63 FR
50244, September 21, 1998) (Ref. 15) and FDA’s Guidance forIndustry: “Characterization and Qualification of Cell Substrates
and Other Biological Materials Used in the Production of Viral
Vaccines for Infectious Disease Indications,” dated February 2010
(Ref. 12).
Cell bank qualification includes tests to:•

Ensure absence of microbial contamination, includingsterility, mycoplasma (and spiroplasma for insect cells),
and in vivo and in vitro testing for adventitious viral agents.
For cell lines used for production of vectors, we

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recommend that you test for retroviral contamination, using
reverse transcriptase (RT) assays and transmission electron
microscopic (TEM) analysis. The presence of anadventitious viral agent in your bank should be vigorously
investigated, and re-derivation of the bank should beconsidered.

•

•

-

For additional information on the analyticalmethods used for cell bank qualification, please see“Analytical Procedures (3.2.S.4.2)” (section
V.A.4.b. of this guidance).

-

For cell lines that have been exposed to bovine or
porcine components (e.g., serum, serum
components, trypsin), appropriate testing would
include testing for bovine or porcine adventitious
agents. See further discussion on bovine andporcine reagents, above.

Ensure absence of species-specific pathogens.
-

For human cells, this may include testing forcytomegalovirus (CMV), HIV-1 & 2, HTLV-1 &-2,
human herpesvirus-6 and -8 (HHV-6 & -8), JC
virus, BK virus, Epstein-Barr virus (EBV), humanparvovirus B19, HBV, human papillomavirus(HPV), and HCV, as appropriate.

-

For other animal or insect cells, we recommend
tests for species-specific viruses, as appropriate.
For instance, for Vero cells, we recommend testingfor simian polyomavirus SV40 and simian
retrovirus.

-

For insect cells, you may evaluate the presence ofarboviruses in a susceptible cell line, such as baby
hamster kidney (BHK21) cells. Insect cell lines
with known viral contamination should be avoided.

Identify cells. Identify your cells through tests that
distinguish them from other cell lines used in your facility.
For cell lines that you have purchased from a typecollection or received from another investigator, werecommend master cell bank (MCB) testing to confirm the19

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purity of the cells by genetic analysis (i.e., short tandem
repeat analysis or other profiling analysis). 4ix.

•

Establish stability of the cell bank. Stability can beassessed by measuring viability of cells over time after
cryopreservation. We also recommend a one-time test of
end of production cells (EOP) or mock production cells ofsimilar passage history, to be tested for their suitability to
produce your vector. For stable retroviral vector producer
cells, we recommend that you test the genetic stability of
the gene insert in the EOP cells.

•

Assess the ability of new cell lines to form tumors. We
recommend that you perform tumorigenicity tests for celllines that have not been previously characterized for theirpotential to form tumors. This test would not be necessary
for cells known to form tumors; please see additional
information on testing for process-related impurities under“Drug Substance Characterization (3.2.S.3)” (section
V.A.3.b.i. of this guidance).
Working Cell Banks

A Working Cell Bank (WCB) may be derived from one or morevials of the MCB. The information needed to document
qualification and characterization for a WCB is less extensive thanthat needed for the MCB. WCB testing should include but is not
limited to sterility, mycoplasma, identity, and in vitro adventitious
agent tests. For additional information on the analytical methods
used for WCB qualification, please see “Analytical Procedures(3.2.S.4.2)” (section V.A.4.b. of this guidance).
x.

Bacterial or Microbial Master Cell Banks

For all bacterial or microbial (e.g., yeast) MCBs, you should
describe the genotype and source of the microbial cells. Bacterial
MCBs are frequently used as a starting material to generate
plasmid DNA, which can be used as a vector for gene transfer or asa manufacturing intermediate for other gene therapy products, suchas the AAV or lentiviral vectors. Microbial MCBs also may be
used to generate a microbial vector for gene therapy. You should
4

Reid Y, Storts D, Riss T, Minor L. Authentication of Human Cell Lines by STR DNA Profiling Analysis. In:
Sittampalam GS, Coussens NP, Brimacombe K. et al., editors. Assay Guidance Manual. Bethesda (MD): Eli Lilly& Company and the National Center for Advancing Translational Sciences; 2004.
https://www.ncbi.nlm.nih.gov/books/NBK144066/.

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provide a detailed description of the history and derivation of thematerials used to generate the cell bank, including information on
how plasmid vectors were designed and constructed. For the bankmaterial, itself, you should provide information on how thematerial was generated and how the bank is stored and maintained
as well as detailed information on qualification of the bank(including cell bank COAs) to adequately establish the safety,
identity, purity, and stability of the microbial cell preparation usedin the manufacturing process.
For bacterial cell banks used to manufacture a DNA plasmid, werecommend MCB testing include:•

Bacterial host strain identity;•

Plasmid presence, confirmed by bacterial growth on
selective medium, restriction digest, or DNA sequencing;•

Bacterial cell count;•

Bacterial host strain purity (no inappropriate organisms,
negative for bacteriophage);•

Plasmid identity by restriction enzyme (RE) analysis;•

Full plasmid sequencing. We recommend that you fully
sequence plasmid vectors and submit an annotatedsequence for the vector, as described in more detail in thesection below on viral vector banks; and•Transgene expression and/or activity.

For microbial cell banks used to manufacture a microbial vector,
our recommendations for MCB testing are outlined in the
Guidance for Industry, “Recommendations for Microbial Vectors
used for Gene Therapy,” dated September 2016 (Ref. 10).
xi.

Master Viral Banks

Viral banks may be expanded for viral vector production, or they
may be used as helper viruses for manufacturing non-replicating
vectors (e.g., AAV or gutless adenovirus). You should provide a
detailed description of the history and derivation of the source or21

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seed materials for these banks. You should describe how the seedstock was generated and what cells and animal-derived materials
were used in the derivation process.
A gene map of the final vector and vector intermediates is usefulwhen describing the history and derivation of recombinant viral
vectors. We recommend that you state whether the seed material
was plaque-purified, purified by limiting dilution, or rescued fromDNA or RNA clones and how many times it was passaged, during
expansion.
For the banked material, itself, you should describe the
manufacturing process and the conditions under which the banked
material was generated, for example, in a research laboratory or a
GMP facility. We recommend that you list animal-derived
materials used in the generation of the bank and state whether the
master virus bank (MVB) is expected to represent a single clone ora distribution of viral variants or sequences.
We also recommend that you provide information on how the bankis stored and maintained as well as detailed information on thequalification of the bank to adequately establish the safety,
identity, purity, and stability of the virus preparation used in the
manufacturing process. If a COA is available, it should besubmitted to the IND. For additional information on the analyticalmethods used for MVB qualification, please see “Analytical
Procedures (3.2.S.4.2)” (section V.A.4.b. of this guidance).
Viral vector bank qualification includes tests to:•

Ensure absence of contamination, including sterility,
mycoplasma, and in vivo and in vitro testing foradventitious viral agents.

•

Ensure absence of specific pathogens that may originate
from the cell substrate, such as human viruses if the cellline used to produce the MVB is of human origin, or
pathogens specific to the origin of the production cell line
(e.g., murine, non-human primate, avian, insect).

•Ensure absence of replication competent virus in
replication incompetent vectors.

•

Ensure viral titer or concentration.

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•

Ensure sensitivity to anti-viral drugs, as applicable, forexample, herpes simplex virus (HSV) sensitivity toganciclovir.

•

Ensure transgene activity, if appropriate.

•

Identify the viral vector and therapeutic transgene (e.g.,
Southern blot or restriction endonuclease analysis), as
needed.

•Ensure the correct genetic sequence. We recommend thatyou fully sequence all vectors that are 40 kb or smaller,
analyze the sequence, and submit an annotated sequence ofthe entire vector. You should provide an evaluation of thesignificance of all discrepancies between the expectedsequence and the experimentally determined sequence andan evaluation of the significance of any unexpectedsequence elements, including open reading frames. We
have the following recommendations, regarding sequence
analysis:-

We recommend that viral vectors be sequenced
from the MVB, when possible.

-

For integrating viral vectors, we recommend thatyou perform DNA sequencing on the integrated
vector. The material for sequencing can becollected from the producer cell line or, in the caseof vectors generated by transient transfection, frommaterial collected from cells that you havetransduced after isolation of a vector lot.

-

For other situations in which no MVB exists,sequencing should be performed from the DS or
DP. For example, AAV vectors are typically madeby plasmid transfection, and the AAV vector isharvested directly from transfected cells to produce
a DS. In this situation, we recommend that you
sequence one or more lots (either material from DS
or DP) to confirm that the vector sequence is stable,
during manufacturing.

-

For viral vectors greater than 40 kb, you shouldsummarize the extent and results of sequence
analysis that you have performed, including any

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testing performed by restriction endonucleaseanalysis. You should perform sequence analysis of
the gene insert, flanking regions, and any regions of
the vector that are modified or could be susceptible
to recombination. The entire vector sequence will
be necessary to confirm identity for licensure.
xii.

Working Viral Banks

A working viral bank (WVB) may be derived from one or morevials of the MVB, and the information needed to document
qualification and characterization of the WVB is less extensive
than that needed for the MVB. You should describe the processused to generate the WVB and whether animal-derived materials
were used. Testing for WVB should include but is not limited tosterility, mycoplasma, identity, and in vitro adventitious agent
tests.
d.

Control of Critical Steps and Intermediates (3.2.S.2.4)

You should describe the control of critical steps and intermediates in the
manufacturing process. Critical control steps include those outlined in the“Description of Manufacturing Process and Process Controls” (section
3.2.S.2.2 of the CTD and section V.A.2.b. of this guidance). We
recommend that you also consider any steps in which in-process tests withacceptance criteria are performed as critical control steps.
You should provide information on the quality and control ofintermediates. Manufacturing intermediates should be defined by the
manufacturer. Intermediates may include material from collection or holdsteps, such as temporary storage of bulk harvest, concentration steps, or
purification intermediates (e.g., column fractions or eluate). The durationof production steps and hold times should be controlled and recorded tofacilitate the establishment of process limits and to allow for future
validation of each step and hold time within the proposed limits in support
of a license application.
Intermediates in gene therapy manufacturing may also include DNA
plasmids that are used in the manufacture of other gene therapy products,
such as AAV or lentiviral vectors. We recommend that DNA plasmidintermediates be derived from qualified banks, as described in more detailabove and in “Control of Materials (3.2.S.2.3)” (section V.A.2.c. of thisguidance). In addition, we recommend that you provide information on
the plasmid manufacturing procedures, reagents, and plasmid
specifications for use. In general, we recommend that this testing include

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assays to ensure the identity, purity, potency, and safety of the final
product. For a DNA plasmid, this may include sterility, endotoxin, purity(including percent of supercoiled form and residual cell DNA, RNA, andprotein levels), and identity testing (restriction digest and sequencing if
sequencing was not performed on the bacterial bank). A COA
documenting plasmid quality testing should be included in the IND.
e.

Process Validation and/or Evaluation (3.2.S.2.5)

Process validation studies are generally or typically not required for earlystage manufacturing, and thus, most original IND submissions will notinclude process performance qualification. We recommend that you use
early stage manufacturing experience to evaluate the need for process
improvements and to support process validation studies in the future.
INDs at all stages of development should have established written
standard operating procedures (SOPs) to ensure proper manufacturingcontrol and oversight. Manufacturing oversight is usually performed by a
dedicated Quality Unit, the duties of which include implementing
procedures to prevent microbial contamination, cross-contamination, andproduct mix-ups. Your Quality Unit should have procedures in place toinvestigate lot failures, out-of-specification results, and ways to implement
corrective actions. Your IND should include a description of your Quality
Unit, including the manner in which quality control testing and oversightare separated from the manufacturing unit.
Additional information on quality systems and process validation can befound in the following FDA guidance documents: “Guidance for Industry:
CGMP for Phase 1 Investigational Drugs,” dated July 2008 (Ref. 16);
“Quality Systems Approach to Pharmaceutical CGMP Regulations,” dated
September 2006 (Ref. 17); and “Process Validation: General Principles
and Practices,” dated January 2011 (Ref. 18). The application of current
good manufacturing practices (CGMPs) is required under section
501(a)(2)(B) of the Federal Food, Drug, and Cosmetic Act at all stages ofclinical investigation. However, the CGMP regulations (21 CFR Part 211)are not required for the manufacture of most investigational new drugs
under Phase 1 INDs (See Ref. 16).
f.

Manufacturing Process Development (3.2.S.2.6)

You should provide a description and discussion of the developmental
history of the manufacturing process described in “Description of
Manufacturing Process and Process Controls” (section 3.2.S.2.2 of the
CTD).

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For early stage INDs, there may be differences between the manufacturing
and testing of the toxicology lots and the material you plan to use in theclinical studies. For later stage INDs, there may be changes to the
manufacturing process as part of process development or optimization. In
both situations, we recommend that you describe how manufacturing
differences are expected to impact product performance. If you makesignificant manufacturing changes, then comparability studies may benecessary to determine the impact of these changes on the identity, purity,
potency, and safety of the product. The extent of comparability testing
will depend on the manufacturing change, the ability of analytical methods
to detect changes in the product, and the stage of clinical development.
For first-in-human studies, any differences between toxicology lots andclinical lots should be assessed for their impact on product safety. For
later phase studies, especially those designed to measure product efficacy,differences in clinical lots should be assessed for their impact on productsafety and activity.
Please note that it is important to retain samples of the DS andmanufacturing intermediates, when possible, in the event thatcomparability studies are necessary during future product development.
3.

Drug Substance Characterization (3.2.S.3)
a.

Elucidation of Structure and Other Characteristics (3.2.S.3.1)

We recommend that you include annotated sequence data for your vector
in the original IND submission. In addition, we recommend that you
provide any further information confirming the primary, secondary, or
higher order structure; post-translational modifications; and/or distributionof cell types for the DS if it has not already been described in “Structure”(section 3.2.S.1.2 of the CTD).
b.

Impurities (3.2.S.3.2)

We recommend that your manufacturing process be designed to remove
process- and product-related impurities and that you have tests in place tomeasure levels of residual impurities. You should describe your test
procedures in the IND with appropriate limits. Your initial specification
for impurities may be refined with additional manufacturing experience.
We recommend that you measure impurities throughout productdevelopment, as this will help ensure product safety, contribute to yourunderstanding of the manufacturing process, and provide a baseline forpotential manufacturing changes in the future.

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i.

Process-Related Impurities

We recommend testing for process-related impurities. These
include but are not limited to residual cell substrate proteins,
extraneous nucleic acid sequences, helper virus contaminants (i.e.,
infectious virus, viral DNA, viral proteins), and reagents usedduring manufacture, such as cytokines, growth factors, antibodies,selection beads, serum, and solvents.
A common process-related impurity for many vector preparations
is residual nucleic acid, such as cell substrate DNA, which can copurify with the vector. Some vectors, including AAV, can also
package (i.e., inside the viral capsid) a large amount of plasmid
DNA sequences (used during transfection) as well as cellularDNA. The presence of these impurities may have adverse effects
on product quality and safety. We recommend that you optimize
your manufacturing process to reduce non-vector DNA
contamination in your product. Additionally, you should monitor
and control the amount of extraneous nucleic acid sequences inyour product.
Since some cell substrates also harbor tumorigenic genetic
sequences or retroviral sequences that may be capable oftransmitting infection, we recommend that you take steps tominimize the biological activity of any residual DNA associatedwith your vector. This can be accomplished by reducing the sizeof the DNA to below the size of a functional gene and by
decreasing the amount of residual DNA. We recommend that you
limit the amount of residual DNA for continuous non-tumorigenic
cells to less than 10 ng/dose and the DNA size to below
approximately 200 base pairs (Ref. 12).
If you are using cells that are tumor-derived (e.g., Hela) or withtumorigenic phenotypes (e.g., 293T, also known as HEK293T) or
other characteristics that give rise to special concerns, more
stringent limitation of residual DNA quantities may be needed toassure product safety. In addition to controlling host cell DNA
content and size, as described above, you should also control thelevel of relevant transforming sequences in your product withacceptance criteria that limit patient exposure. For example,
products made in 293T cells should be tested for adenovirus E1
and SV40 Large T antigen sequences. Your tests should beappropriately controlled and of sufficient sensitivity and specificity
to determine the level of these sequences in your product.

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Some vectors, including AAV, can package a large amount of nonvector DNA (e.g., plasmid DNA, helper virus sequences, cellularDNA), and it may not be possible to remove or reduce this DNA
from the product to a level sufficient to assure safety. Therefore,
we strongly recommend that the cell lines and helper sequencesused to make viral vectors that package non-vector DNA, such as
AAV, be carefully chosen to reduce the risks of the product.
ii.

Product-Related Impurities

Typical product-related impurities for viral vectors may include
defective interfering particles, non-infectious particles, empty
capsid particles, or replicating recombinant virus contaminants.
These impurities should be measured and may be reported as aratio, for example, full:empty particles or virus particles:infectious
units.
For ex vivo genetically modified cells, product-related impurities
include non-target cells, which may be present after selection orenrichment, and unmodified target cells, which may be present
after the ex vivo modification step. We recommend that you
evaluate the nature and number of non-target cells and measure thepercentage of cells that have been genetically modified. As you
develop a greater understanding of the cellular phenotypes present
in your product during clinical development, you may also
consider adding impurity tests for specific cell populations in orderto establish greater manufacturing control.
4.

Control of Drug Substance (3.2.S.4)
a.

Specification (3.2.S.4.1)

You should list DS specifications in your original IND submission.
Specifications are defined as a list of tests, references to analyticalprocedures, and appropriate acceptance criteria used to assess quality.
Acceptance criteria should be established and justified, based on dataobtained from lots used in preclinical and/or clinical studies, data from lots
used for demonstration of manufacturing consistency, data from stability
studies, and relevant development data.
For products in the early stages of clinical development, very few
specifications are finalized, and some tests may still be underdevelopment. However, the testing plan submitted in your IND should be
adequate to describe the physical, chemical, or biological characteristics of28

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the DS necessary to ensure that the DS meets acceptable limits for
identity, strength (potency), quality, and purity(21 CFR 312.23(a)(7)(iv)(a)).
Your IND should include specifications with established acceptancecriteria for safety testing at Phase 1. Safety testing includes tests to ensure
freedom from extraneous material, adventitious agents, microbial
contamination, and replication competent virus. Information on somecommon safety test methods is provided in more detail in the following
section (see “Analytical Procedures (3.2.S.4.2),” section V.A.4.b. of thisguidance). To maximize the sensitivity of safety testing, it is importantthat you perform each test at the stage of production at whichcontamination is most likely to be detected. For example, tests formycoplasma or adventitious viruses (in vivo or in vitro) should be
performed on cell culture harvest material (cells and supernatant) prior tofurther processing, e.g., prior to clarification, filtration, purification, andinactivation.
Your IND should also include specifications for measuring an appropriate
dose level (i.e., strength or potency) at Phase 1. Assays used to determine
dose (e.g., vector genome titer by quantitative polymerase chain reaction(qPCR), transducing units, plaque-forming units, transduced cells) should
be well-qualified prior to initiating dose escalation studies. Information
on how to qualify your dose determining assay is provided in “Validationof Analytical Procedures (3.2.S.4.3)” (section V.A.4.c. of this guidance).
Additional testing will depend on the type of gene therapy product and thephase of clinical development. These tests may include assays to assess
product characteristics, such as identity, purity (including endotoxin andcontaminants, such as residual host cell DNA, bovine serum albumin(BSA), DNase), and potency/strength. For additional information on
potency tests, please refer to the FDA’s Guidance for Industry “Potency
Tests for Cellular and Gene Therapy Products,” dated January 2011 (Ref.
19).
Please note that not all testing listed in this section of the guidance isrequired for release of both the DS and DP. In some cases, repeat testing
may be good practice; however, redundant testing may not always be
feasible or practical. In this case, we recommend that you provide arationale to support the selection of testing performed for release of either
DS or DP.
We provide some additional comments regarding tests for productcharacterization and impurities under “Specifications (3.2.P.5.1)” (section
V.B.5.a. of this guidance).

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b.

Analytical Procedures (3.2.S.4.2)

You should provide a description of all the analytical procedures usedduring manufacturing to assess your manufacturing process and productquality. In your original IND submission, your descriptions should havesufficient detail so that we can understand and evaluate the adequacy of
your procedures. We recommend that you develop detailed SOPs for how
your analytical procedures are conducted at early stages of productdevelopment as a part of your quality system. We acknowledge that,during product development, analytical methods may be modified to
improve control and suitability. However, assay control is necessaryduring all phases of clinical development to ensure product quality andsafety and to allow for comparability studies, following manufacturingchanges.
Documentation submitted in support of your analytical procedures should
describe in detail how a procedure is performed and should specify any
reference standards, equipment, and controls to be used. Submission of
information, such as individual SOPs or batch records, will generally not
be necessary, provided descriptions of your analytical procedures are
sufficiently detailed in your IND. Contractor test reports are acceptable,
provided there is adequate description of the analytical procedure, test
sensitivity, specificity, and controls.
i.

Safety Testing

Safety testing on the DS should include microbiological testing,such as bioburden (or sterility, as appropriate), mycoplasma, andadventitious viral agent testing, to ensure product quality.
Guidelines and/or procedures for many safety tests have been
described in detail, elsewhere (e.g., bioburden, 5 sterility, 6
mycoplasma (Ref. 20), adventitious agent testing, and tests for
specific pathogens (Ref. 12)). Analytical procedures different thanthose outlined in the United States Pharmacopeia (USP), FDA
guidance, or Code of Federal Regulations (CFR) may be
acceptable under IND if you provide adequate information on yourtest specificity, sensitivity, and robustness. Examples of5

USP<61> describes membrane filtration, plate count, and most probable number methods that can be done toquantitatively determine the bioburden of non-sterile DPs. Although 21 CFR 211.110(a)(6) does not specify a test
method, it requires that bioburden in-process testing be conducted pursuant to written procedures during the
manufacturing process of DPs.
6
Sterility testing may be performed on the DS when it cannot be performed on the DP, as outlined in the final rule:
Amendments to Sterility Test Requirements for Biological Products (May 3, 2012; 77 FR 26162 at 26165). Sterility
tests are described in 21 CFR 610.12 and USP<71> Sterility Tests.

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alternative methods, which may be needed for live cells, include
rapid sterility tests, rapid mycoplasma tests (including PCR-based
tests), and rapid endotoxin tests. We recommend that you plan todemonstrate equal or greater assurance of your test methodology,
compared to a compendial method, prior to licensure, as required
under 21 CFR 610.9. We provide some additional comments
regarding these tests under “Specifications (3.2.P.5.1)”(section V.B.5.a. of this guidance) as well as comments regarding
replication competent virus and wild-type oncolytic virus testing,below.
ii.

Replication Competent Virus

For many gene therapy viral vectors, we recommend specifictesting, due to the potential for these vectors to recombine or revert
to a parental or wild-type (WT) phenotype at a low frequency.
Tests for replication-competent, parental, or wild-type viruses that
may be generated during production (e.g., replication-competentadenovirus (RCA) and replication-competent retrovirus (RCR))
should be performed on material collected at the appropriate stageof the manufacturing process. For example, we recommend testingbanked material for the presence of replication-competent viruses
and as a specification for in-process or release testing of DS or DP,
as appropriate (please see further details, below, within thissection).
A.

Replication-Competent Retrovirus (RCR) Testing

Retroviral-based products (including lentivirus and foamy
virus-based products) used for most gene therapy
applications are designed to be replication defective. To
ensure the absence of RCR, you should perform testing for
RCR at multiple points, during production of a retroviral
vector. For further information on retroviral testing, refer
to “Guidance for Industry: Supplemental Guidance on
Testing for Replication Competent Retrovirus in Retroviral
Vector Based Gene Therapy Products and During Followup of Patients in Clinical Trials Using Retroviral Vectors,”
dated November 2006 (Ref. 21). This guidance will besuperseded by “Testing of Retroviral Vector-Based Human
Gene Therapy Products for Replication Competent
Retrovirus During Product Manufacture and Patient
Follow-up; Draft Guidance for Industry,” dated July 2018
(Ref. 22), when finalized.

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B.

Replication-Competent Adenovirus (RCA) Testing

The adenoviral-based products used for most gene therapy
applications are designed to be replication defective. A
notable exception is oncolytic adenoviruses (see “WildType Oncolytic Virus Testing” in section V.A.4.b.ii.D. of
this guidance). RCA may be generated at a low frequency
as a result of homologous recombination between viral
vector sequences and viral sequences present in the cell
substrate, during manufacturing. Therefore, for mostadenoviral-based products, we recommend that you qualify
your MVB for RCA and test either the DS or DP of eachproduction lot for RCA. We recommend a maximum levelof 1 RCA in 3×1010 viral particles.
C.

Replication-Competent AAV (rcAAV) Testing

Preparations of AAV vectors can be contaminated withhelper virus-dependent rcAAV, also referred to as wildtype AAV or pseudo wild-type AAV. These rcAAV are
generated through homologous or non-homologous
recombination events between AAV elements present on
the vector and AAV rep and cap sequences that are present,
during manufacture. While wild-type AAV has no known
associated pathology and cannot replicate without helper
virus, expression of cap or rep genes in infected cells canresult in unintended immune responses, which can reduce
effectiveness and may have unintended safety risks.
Therefore, we recommend that you test for rcAAV, which
could potentially replicate in the presence of helper virus,
and report these results. A number of methods have been
published for evaluating the level of rcAAV, including
amplification of AAV in the presence of helper virus,
followed by PCR for rep/inverted terminal repeats (ITR)
junctions, and PCR for rep and cap sequences, following
DNase digestion of the vector preparation. We do notrecommend a specific method for determining rcAAV in
this guidance. You should describe your test method andassay sensitivity in the IND.

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D.

Wild-Type Oncolytic Virus Testing

Most oncolytic viruses used in gene therapy applications
not only carry transgenes but also have been attenuated or
adapted from a parental virus strain to grow selectively incancer cells. It may be possible for these attenuated or
adapted viruses to either recombine or revert to a parental(or WT) genotype, during manufacture. Therefore, we
recommend that you conduct tests to determine whether theparental virus sequences are present in your product. In
addition, we recommend that you select production cells
that do not contain viral sequences that may allow
homologous recombination with the product. For example,
we do not recommend 293 cell substrates for the
manufacture of E1-modified oncolytic adenoviruses, due tothe potential for homologous recombination with E1
sequences in the 293 cells.
c.

Validation of Analytical Procedures (3.2.S.4.3)

Validation of analytical procedures is usually not required for original
IND submissions for Phase 1 studies; however, you should demonstratethat test methods are appropriately controlled. In general, scientificallysound principles for assay performance should be applied (i.e., tests
should be specific, sensitive, and reproducible and include appropriate
controls or standards). We recommend that you use compendial methods
when appropriate and qualify safety-related tests prior to initiation ofclinical trials.
To ensure safety of gene therapy products, you should also qualify theassays used to determine dose (e.g., vector genome titer by qPCR,
transducing units, plaque forming units) prior to initiating dose escalation
studies. In your original IND submission, you should provide a detailed
description of the qualification protocol (e.g., samples; standards;
positive/negative controls; reference lots; and controls evaluated, such as
operators, reagents, equipment, dates) and data supporting the accuracy,
reproducibility, sensitivity, and specificity of the method. Also critical toensuring safety is the ability to compare the dose used for preclinicalevaluations to the dose to be used for clinical studies. One way to ensurethat the doses compare is to use the same qualified method to quantitate
preclinical and clinical lots. If it is not possible to use the same qualified
method, we recommend that you retain sufficient quantities of preclinicalmaterial to enable side by side testing with the clinical material, using the33

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same qualified method. In addition, you should validate tests used todetermine dose prior to initiating clinical studies to demonstrate efficacy
or support licensure.
Assays used to measure RCR and RCA should also meet our current
recommendations for sensitivity at an early stage of development (seedescriptions “RCR Testing” and “RCA Testing” (section V.A.4.b.ii.A. andB. of this guidance). We recommend that you include relevant positive
and negative controls when conducting these tests and include positive
controls spiked in the test article to assess whether there are any inhibitory
effects of the test article on detection.
For all analytical procedures, we recommend that you evaluate assay
performance throughout product development, have a validation plan inplace during later phase clinical studies, and complete validation before
BLA submission. For more information on validation of analyticalmethods, please see the FDA’s Guidance for Industry: “Q2B Validationof Analytical Procedures: Methodology,” dated November 1996 (Ref.
23).
d.

Batch Analysis (3.2.S.4.4)

You should include a table with test results for all of the batches (or lots)of DS that you have manufactured. For early stage INDs, this may include
only toxicology lots or developmental batches and a single manufacturing
run for clinical grade material. Please note that batches manufactured indifferent ways should be clearly identified in the submission. We
recommend that you annually update this section of your IND as newbatches are produced. You should indicate any batches that fail to meet
release specifications and any action taken to investigate the failure (asoutlined in “Process Validation and/or Evaluation (3.2.S.2.5)” (section
V.A.2.e. of this guidance). We recommend that you retain samples of all
production lots for use in future assay development, validation, or
comparability studies.
e.

Justification of Specification (3.2.S.4.5)

You should provide justification for the DS specifications in your IND.
We recognize that acceptance criteria may be adjusted throughout the
product development stages, based on both manufacturing and clinicalexperience. For early stage clinical studies, production lots may be morevariable than those used in later phase investigations.

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For later stage investigational studies in which the primary objective is togather meaningful data about product efficacy, we recommend that
acceptance criteria be tightened to ensure batches are well-defined andconsistently manufactured.
5.

Reference Standards or Materials (3.2.S.5)

You should provide information on the reference standards or reference materials
used for testing the DS in your original IND submission. We recommend thatyou provide the source and lot number; expiration date; certificates of analyses,
when available; and/or internally or externally generated evidence of identity andpurity for each reference standard.
Three types of reference standards are generally used: 1) certified reference
standards (e.g., USP compendial standards); 2) commercially supplied reference
standards obtained from a reputable commercial source; and/or 3) other materialsof documented purity, custom-synthesized by an analytical laboratory or othernoncommercial establishment. In some cases, the reference material for an assay
will be a well-characterized lot of the gene therapy product, itself. In this case,
we recommend that you reserve and maintain a sufficient amount of material(e.g., part of a production lot) to serve as a reference material.
6.

Container Closure System (3.2.S.6)

You should describe the type(s) of container and closure used for the DS in youroriginal IND submission, including the identity of materials used in theconstruction of the container closure system. We recommend that you determine
whether the containers and closures are compatible with the DS. For an original
IND submission, compatibility with a gene therapy product may be evaluatedduring stability studies or may be based on historical data and experience, using
similar products. You should indicate whether the container is an approved or
cleared device and/or the information is cross-referenced to a master file, as
described in section III. “Administrative Information” of this guidance.
7.

Stability (3.2.S.7)
a.

Stability Summary and Conclusions (3.2.S.7.1)

We recommend that you describe in your original IND submission thetypes of stability studies (either conducted or planned) to demonstrate thatthe DS is within acceptable limits. The protocol should describe thestorage container, formulation, storage conditions, testing frequency, andspecifications (i.e., test methodologies and acceptance criteria). Please35

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note that stability studies may evolve with product development, and if DS
is immediately processed into DP, long term DS stability data may not beneeded.
Your stability analysis may include measures of product sterility (orcontainer integrity), identity, purity, quality, and activity or potency. We
recommend that you provide justification for the test methods andacceptance criteria used in the stability analysis. It is often helpful todemonstrate that at least one or more of the test methods in your stability
analysis are stability-indicating. You may demonstrate a test is stabilityindicating, using forced degradation studies, accelerated stability studies,or another type of experimental system that demonstrates productdeterioration. Information to help you design your stability studies may befound in the following guidance documents: FDA “Guideline forIndustry: Quality of Biotechnological Products: Stability Testing of
Biotechnological/Biological Products,” dated July 1996 (Ref. 24); FDA“Guidance for Industry: Q1A(R2) Stability Testing of New Drug
Substances and Products,” dated November 2003 (Ref. 25); and FDA“Guidance for Industry: Q1E Evaluation of Stability Data,” dated June
2004 (Ref. 26).
b.

Post-Approval Stability Protocol and Stability Commitment(3.2.S.7.2)

We do not recommend that you provide a post-approval stability protocol
and stability commitment in the IND. However, as you progress withproduct development, you may want to consider which stability studies
would be required to determine an expiry date for the approved product or
to support post-approval changes to expiry. We recommend thediscussion of these items at your late phase IND meetings.
c.

Stability Data (3.2.S.7.3)

We recommend that you provide the results of your stability studies inyour IND and update this information on a regular basis (e.g., annual
reports). Information on the qualification of analytical procedures used togenerate stability data should be included in your original IND
submission.
B.

Drug Product (3.2.P)
1.

Drug Product Description and Composition (3.2.P.1)

You should provide a description of the DP and its composition (21 CFR
312.23(a)(7)(iv)(b)). This includes a description of the dosage form and a list of36

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all of its components (active and inactive), the amount on a per unit basis, thefunction, and a reference to quality standards for each component (e.g.,compendial monograph or manufacturers’ specifications). If a drug or device will
be used with your gene therapy as a combination product, we recommend that
quality information for the drug or device be included in section 3.2.P of the CTDwith appropriate hyperlinks to section 3.2.R of the CTD, as described in the FDA“eCTD Technical Conformance Guide: Technical Specifications Document,”
dated November 2017 (Ref. 4). If a placebo treatment is used in the clinical trial,
a separate DP section should be provided for the placebo. In addition, you should
provide a description of any accompanying reconstitution diluents and a
description of the container and closure used for the dosage form andaccompanying reconstitution diluent in a separate DP section, if applicable.
2.

Pharmaceutical Development (3.2.P.2)

The Pharmaceutical Development section should contain information on thedevelopment studies conducted to establish that product formulation,
manufacturing process, container closure system, microbiological attributes, andinstructions for use are appropriate for the stage of clinical development. The
studies described here are distinguished from routine control tests conducted,
according to specifications. Additionally, this section should identify anddescribe the formulation and process attributes (critical parameters) that can
influence batch reproducibility, product performance, and DP quality. Supportive
data and results from specific studies or published literature can be included
within or attached to the Pharmaceutical Development section. Additional
supportive data can be referenced to the relevant nonclinical or clinical sections of
the application.
a.

Components of the Drug Product (3.2.P.2.1)
i.

Drug Substance (3.2.P.2.1.1)

You should describe the compatibility of the DS with thecomponents listed in “Description and Composition of the Drug
Product” (section 3.2.P.1 of the CTD) and the key characteristicsof the DS (e.g., concentration, viability, aggregation state, viral
infectivity) that can influence the performance of the DP.
ii.

Excipients (3.2.P.2.1.2)

You should describe in your original IND submission the choice of
excipients and inactive components of the DP listed in“Description and Composition of the Drug Product” (section
3.2.P.1 of the CTD), their concentration, and the characteristics ofthese excipients that can influence DP performance.

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b.

Drug Product (3.2.P.2.2)
i.

Formulation Development (3.2.P.2.2.1)

You should briefly describe the development of the DP
formulation, taking into consideration the proposed route ofadministration and usage in your IND.
We recommend that you describe any other formulations that havebeen used in clinical or preclinical studies and provide a reference
to such studies, if applicable. If formulation changes were needed
for stability, device compatibility, or safety concerns, thisinformation can be reported here.
ii.

Overages (3.2.P.2.2.2)

In your IND, you should describe whether gene therapy product inexcess of your label claim is added during formulation tocompensate for degradation during manufacture or a product’s
shelf life or to extend shelf life. We do not recommend the use of
overages, and we recommend that you provide justification for an
overage, as described in Guidance for Industry: “Q8(R2)
Pharmaceutical Development,” dated November 2009 (Ref. 6).
iii.

Physicochemical and Biologic Properties (3.2.P.2.2.3)

You should describe the parameters relevant to the performance of
the DP in your IND. These parameters include physicochemical or
biological properties of the product (e.g., dosing units, genotypicor phenotypic variation, particle number and size, aggregation
state, infectivity, specific activity (ratio of infectious to noninfectious particles or full to empty particles), biological activity or
potency, and/or immunological activity). Understanding theseparameters and how they affect product performance usuallyoccurs over the course of product development. More information
on pharmaceutical development and consideration in establishingcritical quality attributes during the clinical research phase can befound in Guidance for Industry: “Q8(R2) Pharmaceutical
Development,” dated November 2009 (Ref. 6).
You should update this section on the physiochemical andbiological properties of your product as you gain a better
understanding of the CQA, during development.

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c.

Manufacturing Process Development (3.2.P.2.3)

You should describe the selection and optimization of the DP
manufacturing process (described in “Description of Manufacturing
Process and Process Controls,” section 3.2.P.3.3 of the CTD) if
development studies have been performed.
d.

Container Closure System (3.2.P.2.4)

You should describe the suitability of the container closure system, which
you have described in the “Container Closure System” (section 3.2.P.7 of
the CTD), for the storage, transportation (shipping), and use of the DP.
We recommend that you consider choice of materials, protection frommoisture and light, compatibility with the formulation (including
adsorption to the container and leaching), safety of materials, andperformance. For more information on container closure systems, refer to
FDA’s “Guidance for Industry: Container Closure Systems for Packaging
Human Drugs and Biologics,” dated May 1999 (Ref. 27).
In the selection of your container closure system, we also recommend thatyou consider how lots of your product will be tested for final productrelease. For gene therapy products that are manufactured in small lot sizes(e.g., autologous cell products or products vialed at very high dose levels),
it may be challenging or not possible to dedicate a final container or
multiple vials for lot release testing. In this case, we recommend that you
consider a final container that can be sampled for release testing or thatyou consider alternatives to final container testing.
e.

Microbiological Attributes (3.2.P.2.5)

We recommend, for live products intended to be sterile, that you provide
details on measures taken to ensure aseptic processing, describe the final
product microbial testing, and address how the integrity of the container
closure system to prevent microbial contamination will be assessed.
f.

Compatibility (3.2.P.2.6)

You should discuss the compatibility of the DP with the diluent used forreconstitution or the delivery device, as appropriate.
We recommend that compatibility studies include measures of bothproduct quantity and product activity (e.g., for viral vectors, a measure ofphysical particles and infectivity to assess both adsorption and39

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inactivation). This in-use and in-device stability data should support
recommended hold times and conditions outlined in the clinical protocol
for patient administration.
3.

Manufacture (3.2.P.3)
a.

Manufacturers (3.2.P.3.1)

You should provide the name, address, and responsibility of eachmanufacturer, including contractor manufacturer(s), involved in the
manufacture and testing of the DP.
For gene therapy-device combination products, we recommend that you
list the manufacturing facilities for the device components and describe
the assembly and testing processes taking place at each site, as describedin FDA’s eCTD Technical Conformance Guide (Ref. 4). You should also
identify whether facilities follow the combination product streamlined
manufacturing approach (as described in FDA’s Guidance for Industry
and FDA Staff: “Current Good Manufacturing Practice Requirements for
Combination Products,” dated January 2017 (Ref. 28) and identify the
specific set of regulations (i.e., 21 CFR Part 211 or Part 820).
b.

Batch Formula (3.2.P.3.2)

You should provide a batch formula that includes a list of all componentsof the dosage form, their amounts on a per-batch basis, and a reference totheir quality standards.
c.

Description of Manufacturing Process and Process Controls(3.2.P.3.3)

You should provide a detailed description of the DP manufacturing
process and identify process controls, intermediate tests, and final productcontrols. Your description should include both flow diagram(s) andnarrative description(s) as well as packaging, product contact materials,
and equipment used. This process can include manufacturing steps, suchas final formulation, filtration, filling and freezing, and process controls
and release testing. For ex vivo genetically modified cells that areadministered immediately after manufacturing, an in-process sterility
testing on sample taken 48 to 72 hours prior to final harvest is one part ofthe sterility testing recommended for product release. Please see“Microbiological Attributes (3.2.P.2.5)” (section V.B.2.e. of thisguidance) for more information on final product sterility testing for freshcells.

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d.

Controls of Critical Steps and Intermediates (3.2.P.3.4)

You should describe the control of critical steps and intermediates in the
manufacturing process. Critical steps should include those outlined in the“Description of Manufacturing Process and Process Controls” (section
3.2.P.3.3 of the CTD) to ensure control as well as steps in which tests withacceptance criteria are performed. We recommend that you provide
justification for acceptance criteria or limits set for these tests. In addition,
you should provide information on the quality and control of intermediatesof the manufacturing process. Manufacturing intermediates are defined by
the manufacturer and may include material from collection steps or holdsteps.
e.

Process Validation and/or Evaluation (3.2.P.3.5)

Process validation is not required for early stage manufacturing, and thus,
most original IND submissions will not include this information.
However, we do recommend that early stage INDs have information on
methods used to prevent contamination, cross-contamination, and productmix-ups. For more information on functions of the Quality Unit under
IND, please see “Process Validation and/or Evaluation (3.2.S.2.5)”(section V.A.2.e. of this guidance).
4.

Control of Excipients (3.2.P.4)
a.

Specifications (3.2.P.4.1)

You should provide specifications for all excipients listed in “Excipients”(section 3.2.P.2.1.2 of the CTD). For purpose of this guidance, an
excipient is any component, in addition to the active ingredient, that is
intended to be part of the final product (e.g., human serum albumin or
Dimethyl Sulfoxide (DMSO)).
b.

Analytical Procedures (3.2.P.4.2)

You should describe your analytical procedures for testing excipients.
c.

Validation of Analytical Procedures (3.2.P.4.3)

Validation of analytical procedures is usually not required for original
IND submissions. We recommend that you provide any available
validation information for the analytical procedures used to test excipients.

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d.

Justification of Specifications (3.2.P.4.4)

You should provide justification for the proposed excipient specifications.
e.

Excipients of Human or Animal Origin (3.2.P.4.5)

For excipients of human or animal origin, you should provide information
regarding source, specifications, description of testing performed, andviral safety data. For human serum, we recommend that you submit
information documenting donor suitability as well as appropriate
infectious disease testing. You should ensure that collection is performed
by a licensed blood bank and that testing meets the requirements describedin 21 CFR Part 640.
f.

Novel Excipients (3.2.P.4.6)

For excipients used for the first time in a DP or used for the first time in aroute of administration, you should provide full details of manufacture,
characterization, and controls, with cross-references to supporting safety
data (nonclinical and/or clinical).
5.

Control of Drug Product (3.2.P.5)
a.

Specifications (3.2.P.5.1)

You should list DP specifications in your original IND submission. Your
testing plan should be adequate to describe the physical, chemical, or
biological characteristics of the DP necessary to ensure that the DP meets
acceptable limits for identity, strength (potency), quality, and purity (21CFR 312.23(a)(7)(iv)(b)). Product lots that fail to meet specifications
should not be used in your clinical investigation without FDA approval.
For early phase clinical studies, we recommend that assays be in place toassess safety (which includes tests to ensure freedom from extraneousmaterial, adventitious agents, and microbial contamination) and dose (e.g.,vector genomes, vector particles, or genetically modified cells) of the
product. Additional information on safety testing and measuring productdose is described in “Specification (3.2.S.4.1)” (section V.A.4.a. of thisguidance).
We recommend that product release assays be performed at the
manufacturing step at which they are necessary and appropriate. For
example, mycoplasma and adventitious agents release testing is
recommended on cell culture harvest material, as discussed in“Specification (3.2.S.4.1)” (section V.A.4.a. of this guidance). In

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addition, sterility, endotoxin, and identity testing are recommended on the
final container product to ensure absence of microbial contamination or todetect product mix-ups that might have occurred during the final DP
manufacturing steps (e.g., buffer exchange, dilution, or finish and fillsteps). DP specifications should be further refined as a part of productdevelopment under IND. We recommend that sponsors establish or, insome cases, tighten acceptance criteria, based on manufacturingexperience as clinical development proceeds. Acceptance criteria should
also be established, based on clinical lots shown to be safe and effective,
when appropriate. We also recommend that sponsors develop testing toassess product potency and have this assay in place prior to pivotal
studies. For licensure, a complete set of specifications to ensure the safety
and effectiveness of the product must include the general biologicalproducts standards, as outlined in 21 CFR Part 610.
b.

Analytical Procedures (3.2.P.5.2)

You should describe the analytical procedures used for testing the DP. If
the analytical procedures are the same as those for the DS, you do notneed to repeat this information unless there is a matrix effect from the DP
on assay performance. Please reference the appropriate section of your
IND, where this information can be found (e.g., Drug Substance“Analytical Procedures,” section 3.2.S.4.2 of the CTD). We have thefollowing additional comments regarding these tests:i.

Sterility

We recognize that the compendial sterility test may not be suitable
for all products. As mentioned in “Analytical Procedures” (section
3.2.S.4.2 of this guidance), rapid sterility tests may be needed forex vivo genetically modified cells administered fresh or withlimited hold time between final formulation and patient
administration.
For ex vivo genetically modified cells that are administered
immediately after manufacturing, in-process sterility testing on
sample taken 48 to 72 hours prior to final harvest is recommended
for product release. For such products, aside from an in-process
sterility test, we also recommend that sponsors perform a rapid
microbial detection test, such as a Gram stain, on the final
formulated product and a sterility test, compliant with 21 CFR
610.12, on the final formulated product.
Under this approach, the release criteria for sterility would bebased on a negative result of the Gram stain and a no-growth result

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from the 48 to 72 hour in-process sterility test. Although theresults of the sterility culture performed on the final product will
not be available for product release, this testing will provide usefuldata. A negative result will provide assurance that an aseptic
technique was maintained. A positive result will provide
information for the medical management of the subject and trigger
an investigation of the cause of the sterility failure. The sterility
culture on the final formulated product should be continued for thefull duration (usually 14 days) to obtain the final sterility test
result, even after the product has been administered to the patient.
In all cases where product release is prior to obtaining results froma full 14-day sterility test, the investigational plan should address
the actions to be taken in the event that the 14-day sterility test isdetermined to be positive after the product is administered to a
subject. You should report the sterility failure to both the clinicalinvestigator and FDA. We recommend that you include results ofinvestigation of cause and any corrective actions in an information
amendment submitted to your IND within 30 calendar days after
initial receipt of the positive culture test result (21 CFR 312.31).
In the case of a positive microbial test result, the clinicalinvestigator should evaluate the subject for any signs of infectionthat may be attributable to the product sterility failure. If thepatient experiences any serious and unexpected adverse drug eventthat could be from administration of the non-sterile gene therapy
product, then you must report this information to FDA in an IND
safety report no more than 15 calendar days after your initialreceipt of the information (21 CFR 312.32). If you determine thatan investigational drug presents an unreasonable and significant
risk to subjects of a positive microbial test result or for any otherreason, you must discontinue those investigations that present therisk and notify FDA, all Institutional Review Boards, and all
investigators (21 CFR 312.56(d)).
In addition, please be aware that a product may sometimes
interfere with the results of sterility testing. For example, aproduct component or manufacturing impurities (e.g., antibiotics)
may have mycotoxic or anti-bacterial properties. Therefore, we
recommend that you assess the validity of the sterility assay using
the bacteriostasis and fungistasis testing, as described in USP <71>
Sterility Tests.

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If you freeze DP before use, we recommend that you performsterility testing on the product prior to cryopreservation so that
results will be available before the product is administered to apatient. However, if the product undergoes manipulation afterthawing (e.g., washing, culturing), particularly if procedures are
performed in an open system, you may need to repeat sterility
testing.
We recommend that you incorporate the results of in-process
sterility testing into your acceptance criteria for final productspecifications.
ii.

Identity

We recommend that identity assays uniquely identify a productand distinguish it from other products in the same facility. This
test is performed on the final labeled product to verify its contents(21 CFR 610.14). Sometimes, a single test is not sufficient todistinguish clearly among products, and therefore, it is goodpractice to use different types of test methods (e.g., vector genome
restriction digest and protein capsid analysis).
If the final product is ex vivo genetically modified cells, werecommend that identity testing include an assay to measure thepresence of vector (i.e., expression assay, restriction digest) or
genetic change and an assay specific for the cellular compositionof the final product (e.g., cell surface markers).
iii.

PurityProduct purity is defined as the relative freedom from extraneous
matter in the finished product, whether or not it is harmful to therecipient or deleterious to the product (21 CFR 600.3). Purity
testing includes assays for pyrogenicity or endotoxin and residual
manufacturing impurities, as outlined under “Impurities(3.2.S.3.2)” (section V.A.3.b. of this guidance) of drug substance,
which include but are not limited to proteins; DNA; cell debris;reagents/components used during manufacture, such as cytokines,
growth factors, antibodies, and serum; and in the case of ex vivo
genetically modified cells, any unintended cellular populations.
Although the rabbit pyrogen test method is the current required
method for testing licensed biological products for pyrogenic
substances (21 CFR 610.13), we generally accept alternative test
methods, such as the Limulus Amebocyte Lysate (LAL), under45

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IND. For any parenteral drug, except those administeredintrathecally, we recommend that the upper limit of acceptancecriterion for endotoxin be 5 EU/kg body weight/hour. For
intrathecally-administered drugs, we recommend an upper limit ofacceptance be set at 0.2 EU/kg body weight/hour.
iv.

Potency

You should describe and justify in your IND all assays that you
will use to measure potency. A potency assay is not required toinitiate early phase clinical studies, but we recommend that you
have a well-qualified assay to determine dose, as described below
and in “Validation of Analytical Procedures (3.2.S.4.3)” (section
V.A.4.c. of this guidance). For additional information on potency
assays, please see FDA’s “Guidance for Industry: Potency Tests
for Cellular and Gene Therapy Products,” dated January 2011
(Ref. 19).
v.

Viability

You should establish minimum release criteria for viability, whereappropriate. For ex vivo genetically modified cells, werecommend a minimum acceptable viability of at least 70 percent.
If this level cannot be achieved, we recommend that you submit
data in support of a lower viability specification, demonstrating,for example, that dead cells and cell debris do not affect the safe
administration of the product and/or the therapeutic effect.
vi.

Cell Number or DoseYour dose-determining assay is an important part of your productspecifications. For additional information on your dosedetermining assay, please see “Specification (3.2.S.4.1)” (section
V.A.4.a. of this guidance). If your final product is a geneticallymodified cell therapy, you should have an acceptance criterion forthe minimum number of modified cells in a product lot. We
recommend that the product dose be based on the total number ofgenetically modified cells.
c.

Validation of Analytical Procedures (3.2.P.5.3)

Validation of analytical procedures is usually not required for original
IND submissions, but we do recommend that you qualify certain safetyrelated or dose-related assays, even at an early stage of development (see46Contains Nonbinding Recommendations
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“Validation of Analytical Procedures (3.2.S.4.3),” section V.A.4.c. of thisguidance). If they are the same as those listed for DS testing, you do notneed to repeat them but should reference that section of your IND.
d.

Batch Analyses (3.2.P.5.4)

You should provide final product COA(s) or a description of batches andresults of batch analyses for the DP.
e.

Characterization of Impurities (3.2.P.5.5)

You should provide information on characterization of impurities if notpreviously provided in “Impurities” (section 3.2.S.3.2 of the CTD).
f.

Justification of Specifications (3.2.P.5.6)

You should provide justification for the DP specifications. See“Justification of Specification (3.2.S.4.5)” (section V.A.4.e. of thisguidance) for additional details.
6.

Reference Standards or Materials (3.2.P.6)

You should provide information on the reference standards or reference materials
used in testing the DP if not previously provided in “Reference Standards orMaterials” (section 3.2.S.5 of the CTD).
7.

Container Closure System (3.2.P.7)

You should provide a description of the container closure systems, including
identity of materials of construction or each primary packaging component and its
specification. You should also provide information on how the container issterilized.
Please see “Container Closure System (3.2.P.2.4)” (section V.B.5.d. of thisguidance) for more information and recommendations, regarding the suitability ofdifferent final product containers.
If the final container is an FDA-cleared device, we recommend that you reference
the 510(k) number for the device in your submission. For device combination
products, we recommend that you include a table of contents for the combination
product (with reference links to other files) in this section, as described in FDA’s
eCTD Technical Conformance Guide (Ref. 4).

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8.

Stability (3.2.P.8)
a.

Stability Summary and Conclusion (3.2.P.8.1)

You should summarize the types of studies conducted, protocols used, andthe results of the studies. Your summary should include, for example,
conclusions regarding storage conditions and shelf life as well as in-use
and in-device storage conditions.
If a short-term clinical investigation is proposed, or if a continuous
manufacturing process with limited product hold times is used, stability
data submitted may be correspondingly limited. For early stage INDs,
stability data for the gene therapy may not be available to support theentire duration of the proposed clinical investigation. Therefore, we
recommend that you submit a prospective plan to collect stability
information and update this information to the IND in a timely manner(e.g., in an annual IND update).
b.

Post-Approval Stability Protocol and Stability Commitment(3.2.P.8.2)

We do not recommend that you provide a post-approval stability protocol
and stability commitment in your IND submission. However, as productdevelopment continues, we recommend that you consult with your Quality
Reviewer to determine the type of studies that will be necessary to support
product expiration dates for commercial manufacturing.
c.

Stability Data (3.2.P.8.3)

You should provide results of the stability studies in your IND in an
appropriate format (e.g., tabular, graphic, narrative). Information on theanalytical procedures used to generate the data should also be included,
and this may be referenced to other sections of your submission (e.g.,“Analytical Procedures,” section 3.2.P.5.2 of the CTD).
C.

Appendices (3.2.A)
1.

Facilities and Equipment (3.2.A.1)

You should provide a diagram, illustrating the manufacturing flow of the
manufacturing areas, information on all developmental or approved products
manipulated in this area, a summary of product contact equipment, andinformation on procedures and design features of the facility, to prevent
contamination or cross-contamination.

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A description of the Quality Unit and the quality control (QC) and quality
assurance (QA) responsibilities may be included in this section.
COAs for all raw materials and reagents described in your IND may be put in thissection.
2.

Adventitious Agents Safety Evaluation (3.2.A.2)

You should provide information assessing the risk of potential contamination withadventitious agents. For non-viral adventitious agents, we recommend that you
provide detailed information on the avoidance and control of transmissible
spongiform encephalopathy agents, bacteria, mycoplasma, and fungi. This
information can include certification and/or testing of components and control ofthe production process. For viral adventitious agents, we recommend that you
provide information on viral safety studies. Study reports and data to support
qualification of your manufacturing components (such as adventitious agents test
reports for banked materials) may be submitted as a part of this appendix. Thesestudies should demonstrate that the materials used in production are consideredsafe and that the approaches used to test, evaluate, and eliminate potential risks,during manufacture, are suitable.
Data collected (i.e., study reports) for adventitious agent testing can be placed inthis section.

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VI.

REFERENCES

1.

Guidance for FDA Reviewers and Sponsors: Content and Review of Chemistry,
Manufacturing, and Control (CMC) Information for Human Gene Therapy
Investigational New Drug Applications (INDs), April 2008,https://www.fda.gov/downloads/BiologicsBloodVaccines/GuidanceComplianceRegulator
yInformation/Guidances/CellularandGeneTherapy/UCM078694.pdf
Guidance for Industry: M4Q: The CTD – Quality, August 2001,
https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guid
ances/UCM073280.pdf
Providing Regulatory Submissions in Electronic Format – Certain Human
Pharmaceutical Product Applications and Related Submissions Using the eCTD
Specifications; Guidance for Industry, April 2018,https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guid
ances/UCM333969.pdf
eCTD Technical Conformance Guide: Technical Specifications Document, November
2017,
https://www.fda.gov/downloads/Drugs/DevelopmentApprovalProcess/FormsSubmission
Requirements/ElectronicSubmissions/UCM465411.pdf
Determining the Need for and Content of Environmental Assessments for Gene
Therapies, Vectored Vaccines, and Related Recombinant Viral or Microbial Products;
Guidance for Industry, March 2015,
https://www.fda.gov/downloads/BiologicsBloodVaccines/GuidanceComplianceRegulator
yInformation/Guidances/CellularandGeneTherapy/UCM439273.pdf
Guidance for Industry: Q8(R2) Pharmaceutical Development, November 2009,https://www.fda.gov/downloads/drugs/guidances/ucm073507.pdf
Guidance for Industry: Q11 Development and Manufacture of Drug Substances,
November 2012,https://www.fda.gov/downloads/drugs/guidances/ucm261078.pdf
Guidance for Industry: Expedited Programs for Serious Conditions – Drugs andBiologics, May 2014,
https://www.fda.gov/downloads/Drugs/Guidances/UCM358301.pdf
M4E(R2): The CTD – Efficacy: Guidance for Industry, July 2017,https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guid
ances/UCM465221.pdf
Recommendations for Microbial Vectors used for Gene Therapy; Guidance for Industry,
September 2016,
https://www.fda.gov/downloads/BiologicsBloodVaccines/GuidanceComplianceRegulator
yInformation/Guidances/CellularandGeneTherapy/UCM466625.pdf
Contract Manufacturing Arrangements for Drugs: Quality Agreements; Guidance forIndustry, November 2016,
https://www.fda.gov/downloads/drugs/guidances/ucm353925.pdf
Guidance for Industry: Characterization and Qualification of Cell Substrates and Other
Biological Materials Used in the Production of Viral Vaccines for Infectious Disease
Indications, February 2010,

2.

3.

4.

5.

6.
7.

8.

9.

10.

11.

12.

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2201
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2221
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2223
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2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239

13.

14.

15.

16.
17.

18.

19.

20.

21.

22.

23.

https://www.fda.gov/downloads/BiologicsBloodVaccines/GuidanceComplianceRegulator
yInformation/Guidances/Vaccines/UCM202439.pdf
Points to Consider in the Manufacture and Testing of Monoclonal Antibody Products for
Human Use, February 1997,
https://www.fda.gov/downloads/biologicsbloodvaccines/guidancecomplianceregulatoryin
formation/otherrecommendationsformanufacturers/ucm153182.pdf
Final Rule: Eligibility Determination for Donors of Human Cells, Tissues, and Cellular
and Tissue-Based Products (69 FR 29786, May 25, 2004),
https://www.gpo.gov/fdsys/pkg/FR-2004-05-25/pdf/04-11245.pdf
Federal Register Notice: International Conference on Harmonisation; Guidance on
Quality of Biotechnological/Biological Products: Derivation and Characterization of Cell
Substrates Used for Production of Biotechnological/Biological Products (63 FR 50244,
September 21, 1998),
https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guid
ances/UCM073471.pdf
Guidance for Industry: CGMP for Phase 1 Investigational Drugs, July 2008,https://www.fda.gov/downloads/drugs/guidances/ucm070273.pdf
Guidance for Industry: Quality Systems Approach to Pharmaceutical CGMPRegulations, September 2006,
https://www.fda.gov/downloads/Drugs/Guidances/UCM070337.pdf
Guidance for Industry: Process Validation: General Principles and Practices, January
2011,
https://www.fda.gov/downloads/drugs/guidances/ucm070336.pdf
Guidance for Industry: Potency Tests for Cellular and Gene Therapy Products, January
2011,
https://www.fda.gov/downloads/biologicsbloodvaccines/guidancecomplianceregulatoryin
formation/guidances/cellularandgenetherapy/ucm243392.pdf
Points to Consider in the Characterization of Cell Lines Used to Produce Biologicals,
July 1993,https://www.fda.gov/downloads/BiologicsBloodVaccines/SafetyAvailability/UCM16286
3.pdf
Guidance for Industry: Supplemental Guidance on Testing for Replication Competent
Retrovirus in Retroviral Vector Based Gene Therapy Products and During Follow-up ofPatients in Clinical Trials Using Retroviral Vectors, November 2006,
https://www.fda.gov/downloads/BiologicsBloodVaccines/GuidanceComplianceRegulator
yInformation/Guidances/CellularandGeneTherapy/ucm078723.pdf
Testing of Retroviral Vector-Based Human Gene Therapy Products for Replication
Competent Retrovirus During Product Manufacture and Patient Follow-up; Draft
Guidance for Industry, July 2018,https://www.fda.gov/downloads/BiologicsBloodVaccines/GuidanceComplianceRegulator
yInformation/Guidances/CellularandGeneTherapy/UCM610800.pdf
Guidance for Industry: Q2B Validation of Analytical Procedures: Methodology,
November 1996,
https://www.fda.gov/downloads/drugs/guidances/ucm073384.pdf

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2243
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2246
2247
2248
2249
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2252
2253
2254
2255
2256

24.

25.

26.

27.

28.

Guideline for Industry: Quality of Biotechnological Products: Stability Testing of
Biotechnological/Biological Products, July 1996,
https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guid
ances/UCM073466.pdf
Guidance for Industry: Q1A(R2) Stability Testing of New Drug Substances andProducts, November 2003,
https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guid
ances/UCM073369.pdf
Guidance for Industry: Q1E Evaluation of Stability Data, June 2004,
https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guid
ances/UCM073380.pdf
Guidance for Industry: Container Closure Systems for Packaging Human Drugs andBiologics, May 1999,
https://www.fda.gov/downloads/drugs/guidances/ucm070551.pdf
Guidance for Industry and FDA Staff: Current Good Manufacturing Practice
Requirements for Combination Products, January 2017,https://www.fda.gov/downloads/RegulatoryInformation/Guidances/UCM429304.pdf

52