Guidance for Industry 
 
 
Information Request and Discipline 
Review Letters Under the 
Prescription Drug User Fee Act
 
 
 
 
 
 
Comments and suggestions regarding this document should be submitted at anytime to Dockets 
Management Branch (HFA-305), Food and Drug Administration, 5630 Fishers Lane, rm. 1061, 
Rockville, MD 20852.  All comments should be identified with the title of this guidance 
document. 
 
Additional copies of this guidance document are available from the Office of Communication, 
Training and Manufacturers Assistance (HFM-40), 1401 Rockville Pike, Rockville, MD 20852-
1448, or by calling 1-800-835-4709 or 301-827-1800, or from the Internet at 
http://www.fda.gov/cber/guidelines.htm. 
 
For questions on the content of the document, contact (CDER) Dr. Sandra Kweder, 301-594-
5400 or (CBER) Robert A. Yetter, Ph.D., 301-827-0373. 
 
 
 
 
 
 
 
 
 
U.S. Department of Health and Human Services 
Food and Drug Administration 
Center for Biologics Evaluation and Research (CBER) 
Center for Drug Evaluation and Research (CDER) 
November 2001 
  Guidance for Industry 
 
Information Request and 
Discipline Review Letters Under 
the Prescription Drug User Fee Act
 
 
 
 
Additional copies of this guidance are available from 
 
Office of Training and Communication 
Division of Communications Management 
Drug Information Branch, HFD-210 
Center for Drug Evaluation and Research 
Food and Drug Administration 
5600 Fishers Lane, Rockville, MD 20857  
(Phone: 301-827-4573), 
Internet:  http://www.fda.gov/cder/guidance/index.htm 
 
or 
 
Office of Communication, Training, and 
Manufacturers Assistance, HFM-40 
Center for Biologics Evaluation and Research 
Food and Drug Administration 
1401 Rockville Pike, Rockville, MD 20852-1448 
(Phone: 301-827-4573), 
Internet: http://www.fda.gov/cber/guidelines.htm 
Fax:  1-888-CBERFAX or 301-827-3844 
Voice Information System: 800-835-4709 or 301-827-1800 
     
 
 
 
U.S. Department of Health and Human Services 
Food and Drug Administration 
Center for Biologics Evaluation and Research (CBER) 
Center for Drug Evaluation and Research (CDER) 
November 2001 
   
Table of Contents 
 
 
I.  INTRODUCTION..............................................................................................................1 
 
II.  BACKGROUND.................................................................................................................1 
 
III. EXPLANATION OF TERMS...........................................................................................2 
 
IV. ISSUANCE AND USE OF INFORMATION REQUEST  
     AND DISCIPLINE REVIEW LETTERS.....................................................................3 
A.  General..........................................................................................................................3 
B.  Applicant Response and Effect on the User Fee Clock ............................................4 
 
 
 
   
1
GUIDANCE FOR INDUSTRY   
Information Request and Discipline Review Letters Under the Prescription 
Drug User Fee Act 
 
 
This guidance document represents the agencys current thinking on information request and 
discipline review letters under the Prescription Drug User Fee Act.  It does not create or 
confer any rights for or on any person and does not operate to bind FDA or the public.  An 
alternative approach may be used if such approach satisfies the requirements of the applicable 
statutes and regulations. 
 
I.  INTRODUCTION 
 
This guidance for industry explains how the Agency will issue and use information request 
(IR) letters and discipline review (DR) letters during the review of products in original human 
drug applications as defined in section 735(1) of the Federal Food, Drug, and Cosmetic Act 
(21 U.S.C. 379g(1)) (PDUFA products).  This guidance does not apply to supplemental 
applications, resubmissions, or to applications for non-PDUFA products. 
 
In a November 1997 letter to Congress regarding the reauthorization of the Prescription Drug 
User Fee Act (PDUFA) as part of the Food and Drug Administration Modernization Act of 
1997, the Secretary of Health and Human Services committed the Food and Drug 
Administration to certain user fee performance goals and additional procedures related to the 
review of PDUFA products.  These include the goals of reviewing and acting on increasing 
percentages of applicants' original new drug applications (NDAs) or biologics license 
applications (BLAs), within 6 months for priority applications and within 10 months for 
standard applications for drugs and biologics.  The term review and act on means the issuance 
of an action letter after the complete review of a filed application.  In addition to the 
performance goals for application review, to help expedite the development of drugs and 
biologics, the Secretary specified that FDA intends to provide early Agency thoughts on 
possible deficiencies to applicants in a letter as each discipline finishes its initial review of its 
portion of the pending application (except when it results in the ability to issue an action 
letter). 
 
II. BACKGROUND 
 
Upon implementation of the Prescription Drug User Fee Act of 1992 (PDUFA 1), the Center 
for Biologics Evaluation and Research (CBER) and the Center for Drug Evaluation and 
Research (CDER) undertook to review and act on complete NDAs and BLAs within agreed 
                                                                 
1 This guidance has been prepared by the Review Management Working Group comprising individuals in the 
Centers for Drug Evaluation and Research (CDER) and Biologics Evaluation and Research (CBER) at the Food 
and Drug Administration.  
  - 1 -   
upon time frames.  As part of this undertaking FDA instituted the use of two types of letters, 
action letters and IR letters.  FDA issued an action letter (not approvable, approvable or 
approval letter) after a complete review of the application.  If not an approval, the action letter 
contained a complete list of deficiencies in the application and completed the review cycle for 
the application.  The next review cycle (resubmission) began when the agency receive a 
complete response to all deficiencies listed in the letter.  CDER and CBER used IR letters to 
ask for information that would assist reviewers during the course of the review or to convey 
deficiencies identified in the application in advance of the issuance of an action letter. These 
IR letters did not stop the review clock, did not signal the completion of a review cycle, and 
were not used consistently across divisions or centers. 
 
In discussions held to prepare for the reauthorization of PDUFA (PDUFA 2), industry 
proposed that applicants be notified of any deficiencies in an NDA or BLA as early as 
possible after a discipline review had been completed.  It was agreed that deficiencies would 
be communicated in a specific type of letter.  The company could then begin preparing a 
response to the deficiencies, thereby decreasing the response time to the Agency and 
potentially expediting availability of products to consumers.  Although the enclosure to the 
PDUFA 2 goals letter signed by Secretary Shalala refers to these as IR letters, FDA finds that 
it will be less confusing if these letters are clearly identified as a unique type of letter, the DR 
letter.  Consequently the Agency will continue to use an IR letter, if needed, to request 
information while a specific discipline review is in progress and institute the use of a DR 
letter to convey early thoughts on possible deficiencies in the discipline's section of the 
application when a discipline review is complete. 
 
A discipline review refers to the review of sections of the NDA and BLA by staff with that 
expertise.  These sections include, but are not limited to, the clinical section, the chemistry, 
manufacturing and controls section, the non-clinical pharmacology and toxicology section, 
and the human pharmacokinetics and bioavailability section.  As part of their PDUFA 2 
commitments at the conclusion of a discipline review, CBER and CDER will send a discipline 
review letter to the applicant identifying deficiencies in that particular discipline's portion of 
an application as described in this document, unless the discipline review completes the 
review of the application. 
 
III.  EXPLANATION OF TERMS 
 
An action letter is a letter to an applicant that is issued after the complete review of a filed 
application.  If the letter is not an approval letter, it will set forth in detail the specific 
deficiencies and, where appropriate, the actions necessary to place the application in  
condition for approval.  An action letter may contain additional or fewer deficiencies than 
were provided in previously issued DR letters, depending on the final review of the 
application and supervisory evaluation by Division and/or Office Directors.  The issuance of 
an action letter completes the review cycle for a pending application.  It is the benchmark by 
which the Agency's performance against the PDUFA application review goals is measured. 
 
A DR letter is a letter used to convey early thoughts on possible deficiencies found by a 
discipline review team for its portion of the pending application at the conclusion of the 
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discipline review.  FDA does not consider DR letters to be action letters because they do not 
represent a complete review of the submission and, therefore, do not stop the user fee review 
clock.  In addition, a DR letter does not necessarily reflect input from upper supervisory levels 
(i.e., Division or Office Directors).  A single DR letter may contain comments from multiple 
discipline reviews if it is more efficient to do so. FDA may review such information if it 
determines that such review would not adversely affect its ability to meet its PDUFA 
performance goal for that review cycle. FDA has no obligation to review information 
submitted in response to a DR letter during the review cycle in which the DR letter was 
issued.  
 
An IR letter is a letter sent to an applicant during an application review to request further 
information or clarification that is needed or would be helpful to allow completion of the 
discipline review.  FDA does not consider IR letters to be action letters because they do not 
represent a complete review of the submission and therefore do not stop the user fee review 
clock.  As with DR letters, an IR letter does not necessarily reflect input from upper 
supervisory levels.  However, IR letters are not like DR letters in that FDA issues IR letters 
while the discipline review continues.  Information requested in IR letters should be 
information that would assist in the completion of the review and, as such, would usually be 
reviewed during the review cycle in which the IR letter was issued. 
 
The user fee review clock measures the time elapsed during which an application is under 
review by CBER or CDER (i.e., a review cycle).  The review clock starts at Agency receipt of 
an NDA or BLA that is subsequently filed, or a complete resubmission and stops when the 
agency issues an action letter to the applicant. 
 
IV.  ISSUANCE AND USE OF INFORMATION REQUEST AND DISCIPLINE  
 REVIEW LETTERS 
 
A.  General 
 
CBER and CDER will use IR letters to obtain clarifying information to assist in 
completing a review.  Because the Agency issues IRs to obtain clarification, it is normally 
expected that the applicant will respond as quickly as possible.  FDA reviews such 
responses (if they are of a clarifying nature) as part of the current review cycle of the 
application.  However, if the response is of a significant nature, the response could 
constitute a major amendment.  Major amendments to an original application received in 
the last three months of the review cycle may extend the Action Due date by three months.  
Only one such extension is permitted.  FDA may defer the review of a response to the 
next review cycle, if the review team believes that the new information cannot be fully 
reviewed in the time remaining in the current review cycle or is ready to issue an action 
letter. 
 
To help expedite the development of drug and biologic products, under PDUFA 2, CBER 
and CDER will generally convey early thoughts on possible deficiencies to applicants in 
the form of a DR letter as each discipline finishes its review of its section of the pending 
application, unless the discipline review completes the review of the application.  FDA 
will not issue a DR letter if its issuance would delay or coincide with the issuance of an 
  - 3 -   
action letter.  You should not construe the absence of a DR letter for a particular discipline  
to mean that the action letter will not contain any deficiencies for that discipline.  
Comments in a DR letter will usually reflect the input of the review team but not that of 
the review division director or office director. 
 
The DR letter will allow applicants to know as soon as possible the review team's early 
thoughts on possible deficiencies that have been identified within specific sections of the 
application.  With this information they can begin to assemble the needed data to address 
these deficiencies. DR letters will only contain items that the review team believes require 
resolution prior to approval of the product.  A DR letter intended to convey deficiencies 
found during a discipline review will be clearly distinguishable from IR letters, which are 
requests for clarifications needed to proceed with the on-going review. 
 
Applicants should be aware that because the DR letter will originate at the review team 
level, supervisors may add or delete items in the course of their evaluation, resulting in 
more or fewer deficiencies in the subsequent action letter.  In addition, as reviews from 
different disciplines are integrated, additional concerns might arise or previously stated 
concerns may be resolved. Therefore, applicants could spend time gathering information 
that in the end may not be necessary for responding to the action letter.  This possibility 
was raised during PDUFA 2 discussions with industry representatives, and it was agreed 
during those discussions that the DR letter program should be evaluated to determine if it 
truly helps achieve the goal of reducing the time it takes to make products available to the 
consumer (i.e. if the benefit of early notification of possible deficiencies outweighs the 
possibility of unnecessary extra work on the part of industry). 
 
B.   Applicant Response and Effect on the User Fee Clock 
 
The IR letters and DR letters will not affect the user fee review clock for a given review 
cycle.  The review team will review responses to IR letters and DR letters during the 
current review cycle at the discretion of the review team.  Normally, unless the amount 
and type of information is substantive or voluminous, FDA will review a clarifying IR 
letter response during the current review cycle.  We may or may not consider a response 
to a DR letter conveying deficiencies identified in a discipline review of an original 
application a major amendment, which would extend the review time for the current 
review cycle. At the Division's discretion, it may review the response if the review can be 
completed in the current review cycle.  The Agency is not obligated to review the 
response before the issuance of an action letter.  If the Agency determines that it cannot 
review the newly submitted data before the user fee action due date, it may defer review 
of the response.  If the review team is ready to issue an action letter, review of the 
response could also be deferred.  When FDA defer the review of a response it will be 
reviewed during the next review cycle for the application as part of the complete 
resubmission if the applicant references such response in the resubmission. 
 
Deficiencies addressed in a response to an IR letter or a DR letter may appear in an action 
letter if the review of the response has been deferred or if concerns remain after review of 
  - 4 -   
the response.  The action letter will include all deficiencies that must be answered in order 
to place the application in condition for approval. 
 
If the applicant has already submitted a complete response to all of the outstanding 
deficiencies, the applicant may simply refer to such responses in the complete 
resubmission that responds to the action letter; further reiteration of previously submitted 
information is not necessary.  However, the applicant should clearly identify in the 
resubmission all such responses that are required to complete the resubmission as such. 
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