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Frequently Asked Questions

Contents

Additional questions may be sent to register@clinicaltrials.gov.

General

Is there a charge for listing studies on ClinicalTrials.gov?

No, there is no charge for listing studies on ClinicalTrials.gov. ClinicalTrials.gov is a free service of the National Institutes of Health, provided through the National Library of Medicine.

My study is not yet approved by a human subjects review board (ethics review committee, institutional review board). Can I enter it on ClinicalTrials.gov?

Most studies require approval from a human subjects review board. If your study requires approval, you may register your study on ClinicalTrials.gov prior to getting approval if the Overall Recruitment Status of the study is Not yet recruiting (see Overall Recruitment Status data element on ClinicalTrials.gov).

If a study requires human subjects review board approval, approval must be obtained before the study's Overall Recruitment Status is changed to Recruiting. When board approval is obtained, please update the Protocol Section of the study record in the Protocol Registration and Results System (PRS) and Release (submit) the study for processing.

See How to Register Your Study and How to Edit Your Study Record for more information.

Why can't I find my study on ClinicalTrials.gov?

It might not have been Released (submitted) to ClinicalTrials.gov for processing. After a record has been entered into PRS (or modified) and marked as Complete, it must be Approved and Released by the Responsible Party (see Responsible Party data element on ClinicalTrials.gov).

The study might also be undergoing review. After the Responsible Party Releases (submits) information to ClinicalTrials.gov, that information undergoes a manual review to identify possible errors, deficiencies, or inconsistencies that are not detected automatically during data entry. The Responsible Party will be notified of any issues that need correction, usually within a few days after release of the protocol information. The review of results information may take longer (up to 30 days).

See How to Register Your Study and How to Submit Your Results for more information.

When will the NCT Number for my study be assigned?

The NCT Number, also called the ClinicalTrials.gov Identifier, is assigned after the protocol information has been Released (submitted) by the Responsible Party and passed review by ClinicalTrials.gov staff. At that time an e-mail notification containing the NCT Number is sent. The record, including its NCT Number, will typically be available on ClinicalTrials.gov within 2–5 business days after it is Released.

See How to Register Your Study for more information.

Can I register a study after it has started, has closed to recruitment, or has been completed?

Yes, you can register a study on ClinicalTrials.gov at any time. Please note that, in general, Section 801 of the Food and Drug Administration Amendments Act (FDAAA 801) requires Applicable Clinical Trials to be registered within 21 days of enrollment of the first participant. In addition, the International Committee of Medical Journal Editors and other journals require registration of clinical trials prior to enrollment of the first participant.

See FDAAA 801 Requirements for more information.

Must clinical studies with no external sources of funding ("unfunded" studies) be registered on ClinicalTrials.gov?

The registration requirements of Section 801 of the Food and Drug Administration Amendments Act (FDAAA 801) (PDF) and the International Committee of Medical Journal Editors (ICMJE) policy on Clinical Trial Registration under the ICMJE Recommendations do not exclude clinical studies with no external sources of funding ("unfunded" studies). See FDAAA 801 Requirements for more information on which trials must be registered under FDAAA 801.

In general, an unfunded study should be registered via the PRS account of the Sponsor. When an investigator is considered the Sponsor (a Sponsor-Investigator), the study should be registered using the PRS account of the investigator's affiliated institution with the Responsible Party indicated as Sponsor-Investigator. ClinicalTrials.gov will then display the investigator as the Sponsor instead of the investigator's institution. The Protocol Registration Data Element Definitions page on ClinicalTrials.gov describes the related data elements for Responsible Party.

How do I contact ClinicalTrials.gov if I have a question about my study record?

If you have questions or need help updating your record, e-mail register@clinicaltrials.gov. If the question is about a specific study record, please provide the NCT Number or the Unique Protocol ID (if an NCT Number has not yet been assigned). Please include enough information about the issue so that we may better assist you. We generally respond to all e-mails within 1 business day.

Do I need to register each single-patient investigational new drug application (IND) or protocol exception (including for emergency use) separately?

No, manufacturers or Sponsors accepting requests for single-patient investigational new drug applications (INDs) or protocol exceptions (including for emergency use) should provide only one expanded access record.

See the Registering Expanded Access Records section of the How to Register Your Study for more information.

Protocol Registration and Results System (PRS)

Can an organization have multiple users for a single account?

Yes. When sponsors or their representatives register to become PRS data providers, they will be given information on using PRS, including instructions for creating additional user accounts.

See How to Apply for an Account for more information.

Can registration and results information be uploaded electronically to ClinicalTrials.gov?

Yes. This option is available in PRS as an HTTP upload of an Extensible Markup Language (XML) file. After obtaining a PRS account, login to PRS and review the User's Guide for information on XML upload.

See How to Apply for an Account for help with obtaining a PRS account.

Section 801 of the Food and Drug Administration Amendments Act (FDAAA 801)

To comply with FDAAA 801, must I submit information to ClinicalTrials.gov, or can I use another registry or results database?

You must use ClinicalTrials.gov to fulfill the requirements of FDAAA 801 (PDF). FDAAA 801 requires Responsible Parties to submit clinical trial information to the Director of the National Institutes of Health (NIH) for inclusion in the registry and results database established via ClinicalTrials.gov.

Does FDAAA 801 only apply to industry-sponsored studies?

No. FDAAA 801 applies to any clinical study that meets the definition of an Applicable Clinical Trial and that was initiated after September 27, 2007, or that was initiated on or before that date and was still ongoing as of December 26, 2007. FDAAA 801 does not distinguish between types of sponsors or funding sources in establishing requirements for registration and results submission.

For complete statutory definitions and more information on the meaning of Applicable Clinical Trial, see Elaboration of Definitions of Responsible Party and Applicable Clinical Trial (PDF).

Does the definition of applicable clinical trial under FDAAA 801 only include studies conducted under an FDA Investigational New Drug Application (IND) or Investigational Device Exemption (IDE)?

No. A clinical investigation of a drug can be an Applicable Drug Clinical Trial under FDAAA 801 even if it does not require an IND, and a clinical investigation of a device can be an Applicable Device Clinical Trial whether or not an IDE is required.

See Elaboration of Definitions of Responsible Party and Applicable Clinical Trial (PDF) for more information.

Am I required to submit to ClinicalTrials.gov the results of a clinical trial that is not an applicable clinical trial?

Results submission is not required under FDAAA 801 for a clinical trial that is not an Applicable Clinical Trial (for example, a phase 1 trial studying an FDA-regulated investigational new drug). If a Responsible Party chooses to voluntarily submit results for such a trial, however, the Voluntary Submissions (PDF) provision of FDAAA 801 may apply.

Under the Voluntary Submissions (PDF) provision, a Responsible Party who submits results for such a clinical trial must submit complete clinical trial results information and must also submit results for each Applicable Clinical Trial that is required to be submitted to FDA under Sections 505, 510(k), 515, and 520(m) of the Federal Food, Drug, and Cosmetic Act or Section 351 of the Public Health Service Act for the same use studied.

How do I submit results information if the trial is terminated (that is, stopped prematurely) and no data were collected for one or more Outcome Measures?

If no participants were ever enrolled in the trial, set the Overall Recruitment Status to Withdrawn, and no further results information will need to be submitted.

For a trial that was terminated after participants were enrolled, provide any available data. If no data are available for any of the Outcome Measures, specify zero ("0") for the Number of Participants Analyzed in each Arm/Group, and leave the data fields blank. In this case, provide an explanation in the Analysis Population Description for why zero participants were analyzed and, if appropriate, provide information in the Limitations and Caveats module. Even if data are not entered for Outcome Measures, submit the available data for the enrolled participants in the Participant Flow, Baseline Characteristics, and Adverse Events modules.

I completed a clinical trial that studied an investigational product (drug, biological product, or device that is not initially approved, licensed, or cleared by the FDA). There is no intent to seek approval, clearance, or licensure of the product by the FDA (for example, development of the investigational product has been terminated). How do I indicate that results need not be submitted for this trial?

The Responsible Party may Certify Initial Approval in the PRS. This indicates that the clinical trial was completed before a drug, biological product, or device studied in the trial was initially approved, licensed, or cleared by the FDA for any use.

Final Rule for Clinical Trials Registration and Results Information Submission (42 CFR Part 11)

How do I determine if my study is an applicable clinical trial?

The Final Rule for Clinical Trials Registration and Results Information Submission (42 CFR Part 11) stated that a checklist-based tool would be available to assist Responsible Parties in evaluating whether their clinical trial or study is an applicable clinical trial (ACT) as defined in in 42 CFR 11.10(a) based on the conditions outlined in 42 CFR 11.22(b) (Determination of applicable clinical trial for a clinical trial or study initiated on or after January 18, 2017).

The Checklist and Elaboration for Evaluating Whether a Clinical Trial or Study is an Applicable Clinical Trial (PDF) document follows the criteria specified in 42 CFR 11.22(b), as explained further in the preamble, to determine whether a study initiated on or after January 18, 2017, is an ACT subject to "expanded" registration requirements under the final rule.

Beyond their primary purpose, the ACT Checklist and Elaboration may also be useful to assist in evaluating whether a clinical trial or study that was initiated before January 18, 2017, and which is not subject to the final rule requirements, is an ACT under section 402(j) of the Public Health Service Act.

We note that Responsible Parties or other users of the ACT Checklist and Elaboration are responsible for using accurate data about a clinical trial or study and for properly evaluating whether the trial or study must be registered and, if so, which results must be submitted. The outcome generated from the ACT Checklist will not be retained by the National Institutes of Health (NIH) and will not be binding on either the user or any government agency in any future action(s).

If a clinical trial is not an applicable clinical trial (ACT) at study initiation because it is conducted entirely outside the United States, but the trial subsequently opens a U.S. site, am I required to register the trial?

If a sponsor of a clinical trial in a foreign country that does not meet the definition of an ACT, and has an initiation date after the effective date of the regulations in 42 CFR Part 11, decides to add a location in the U.S. (or its territories), and as a result the trial meets the definition of an ACT, the sponsor becomes subject to 402(j) of the Public Health Service Act and 42 CFR Part 11. The requirements set forth in the regulation would need to be met, beginning with registration of the ACT not later than 21 days after the enrollment of the first participant at the U.S. site. Per 42 CFR 11.22(b), "[a] clinical trial or study that, at any point in time, meets the conditions listed in paragraph (b)(1) or (2) of this section will be considered to meet the definition of an applicable clinical trial." Therefore, this trial would become an ACT when it adds the U.S. site. Clinical trial registration information must include information applicable to the entire trial, as is the case with all multi-site trials with information in ClinicalTrials.gov, because the entire clinical investigation is considered to be the applicable device or drug clinical trial (see 81 FR 65013, 81 FR 65015).

If my study is an applicable clinical trial (ACT), am I required to register?

The regulations at 42 CFR 11.22(a) require the registration of any ACT that is (1) initiated after September 27, 2007, or (2) initiated on or before September 27, 2007 and is ongoing (i.e., not yet reached the Primary Completion Date) on December 26, 2007.

What registration information must I submit if my applicable clinical trial is required to be registered?

The regulations at 42 CFR 11.28 address which registration information requirements apply to which studies. The "Applicability of Requirements in 42 CFR Part 11" table may be used to evaluate whether the registration information requirements in 42 CFR Part 11 or section 402(j) of the Public Health Service (PHS) Act apply to specific studies. (81 FR 65121)

As outlined in the table, required registration information is determined by the study initiation date. The initiation date is the date on which the trial is initiated (i.e., the actual Study Start Date as defined in 42 CFR 11.10(b)(16). (81 FR 65120)

  • Study Start Date on or before September 27, 2007, and ongoing on December 26, 2007: Follow requirements in section 402(j)(2)(A)(ii) of the PHS Act.
  • Study Start Date after September 27, 2007 but before January 18, 2017: Follow requirements in section 402(j)(2)(A)(ii) of the PHS Act.
  • Study Start Date on or after January 18, 2017: Follow requirements specified in 42 CFR 11.28 of the final rule.

When must I submit the required clinical trial registration information?

The regulations at 42 CFR 11.24(a) require that, for an applicable clinical trial for which registration information is required to be submitted, the registration information specified in section 402(j)(2)(A)(ii) of the PHS Act or 42 CFR 11.28(a) must be submitted within 21 days after the first human subject is enrolled. The final rule in 42 CFR 11.10(a) defines "enroll or enrolled" to mean a "human subject's, or their legally authorized representative's, agreement to participate in a clinical trial following completion of the informed consent process, as required in 21 CFR part 50 and/or 45 CFR part 46, as applicable." The definition further states that "for the purposes of ... [42 CFR part 11], potential subjects who are screened for the purpose of determining eligibility for a trial, but do not participate in the trial, are not considered enrolled, unless otherwise specified by the protocol."

For an applicable device clinical trial that is a pediatric postmarket surveillance of a device product and is not a clinical trial, the registration information specified in section 402(j)(2)(A)(ii) of the PHS Act or 42 CFR 11.28(b) must be submitted within 21 days after FDA approves the postmarket surveillance plan.

Am I required to submit results information for my applicable clinical trial (ACT)?

The regulations at 42 CFR 11.42 address those applicable clinical trials for which a responsible party must submit results information. The "Applicability of Requirements in 42 CFR Part 11" table may be used to evaluate whether the results information requirements in 42 CFR Part 11 or section 402(j) of the Public Health Service (PHS) Act apply to specific applicable clinical trials. (81 FR 65121)

As outlined in the table, required results information is determined by the Primary Completion Date:

  • For ACTs that are required to be registered and with a Primary Completion Date before January 18, 2017:
    • If the ACT studies a drug, biological, or device product that is approved, licensed or cleared as of the Primary Completion Date, then the responsible party is required to submit the results information specified in sections 402(j)(3)(C) and 402(j)(3)(I) of the PHS Act. (42 CFR 11.42(a)(1))
    • If the ACT studies a drug, biological, or device product that is not approved, licensed, or cleared as of the Primary Completion Date, then the responsible party is not required to submit results information. (42 CFR 11.42(b))
  • For ACTs that are required to be registered and with a Primary Completion Date on or after January 18, 2017:
    • If the ACT studies a drug, biological, or device product that is approved, licensed or cleared as of the Primary Completion Date, then the responsible party is required to submit the results information specified in 42 CFR 11.48. (42 CFR 11.42(a)(2))
    • If the ACT studies a drug, biological, or device product that is not approved, licensed, or cleared as of the Primary Completion Date, then the responsible party is required to submit the results information specified in 42 CFR 11.48. (42 CFR 11.42(b))

The regulations at 42 CFR 11.60 also establish requirements for the voluntary submission of results information that are not otherwise required to be submitted under 42 CFR 11.42.

When is required clinical trial results information due?

For applicable clinical trials that are subject to 42 CFR 11.42, the standard submission deadline for results information is no later than 1 year after the study's Primary Completion Date, as described in 42 CFR 11.44(a) of the final rule.

The regulations provide for the delayed submission of results information under certain conditions (see 42 CFR 11.44(b)) with certification if the responsible party is seeking approval, licensure, or clearance of a new use being studied for a product that previously has been approved, licensed, or cleared by the FDA. For applicable clinical trials with a Primary Completion Date on or after January 18, 2017, the final rule in 42 CFR 11.44(c) also provides for the delayed submission of results information under certain conditions with certification if the responsible party is seeking initial approval, licensure, or clearance for the studied product. The deadline for the delayed submission of results information as specified in 42 CFR 11.44(b) or 42 CFR 11.44(c) is 30 calendar days after the earliest of specific events described in each provision, with a maximum deadline for delayed results information submission of 2 years after the date of submission of the certification. Specific deadlines are also described in 42 CFR 11.44(d) of the final rule for the submission of partial results information. An extension for good cause may be requested under conditions specified in 42 CFR 11.44(e) of the final rule. The preamble explains that such requests will be granted in limited circumstances. (81 FR 65076-79)

Is a protocol and statistical analysis plan (SAP) required to be submitted?

The regulations at 42 CFR 11.48(a)(5) require a copy of the protocol and SAP (if not included in the protocol) to be submitted as part of clinical trial results information for those applicable clinical trials with a Primary Completion Date on or after January 18, 2017. The submission of a protocol and SAP is not required for those applicable clinical trials with a Primary Completion Date before January 18, 2017.

The regulations at 42 CFR 11.48(a)(5) also state that a "responsible party may redact names, addresses, and other personally identifiable information, as well as any trade secret and/or confidential commercial information (as those terms are defined in the Freedom of Information Act (5 U.S.C. 552) and the Trade Secrets Act (18 U.S.C. 1905)) contained in the protocol or statistical analysis plan prior to submission, unless such information is otherwise required to be submitted under this part."

Additional information about redaction of protocols is also provided in the preamble to 42 CFR part 11. (81 FR 64999 - 65002) This information includes noting that "[m]ore specific guidance regarding redaction will be considered in the future" and that the "protocol and statistical analysis plan must be submitted in a common electronic document format specified at https://prsinfo.clinicaltrials.gov."

The protocol and, if separate, the SAP are to be posted with other clinical trial results, in accordance with 42 CFR 11.52. (81 FR 65002)

Who should submit an Expanded Access record?

The final rule clarifies that expanded access (EA) use of a drug, biological, or device product is not considered an "applicable clinical trial" (ACT) under the definition in 42 CFR 11.10 (81 FR 65009-10). Thus, the submission of clinical trial registration and results information for EA use would not be required by 42 CFR 11.22 and 42 CFR 11.42.

However, for "applicable drug clinical trials" that are required to submit the registration information specified in 42 CFR 11.28, and the responsible party is both the drug manufacturer and trial sponsor, information on the availability of investigational drug products for expanded access is required to be submitted as part of the registration information under 42 CFR 11.28(a)(2)(ii)(H). In addition, an expanded access record must be submitted as required under 42 CFR 11.28(c) to provide details about how to obtain access to the investigational drug (including biological) product. The regulations at 42 CFR 11.64(a)(1)(ii)(D) and (E) requires this availability of expanded access and expanded access record information to be updated. More information about the expanded access submission requirements is available in the final rule preamble. (81 FR 65059-62)

What is the final rule's effective date and compliance date?

As explained in the final rule preamble in Section IV.F. Effective Date, Compliance Date, and Applicability of Requirements in this Part (81 FR 65118-122), the effective date is on January 18, 2017 and the compliance date is on April 18, 2017. Responsible parties have until April 18, 2017, to come into compliance with the requirements of the final rule. For more information on the final rule implementation, see https://prsinfo.clinicaltrials.gov.

This page last reviewed in February 2017