Investigational New Drug (IND) Application - Complete University-Level Guide

1. DEFINITION AND OVERVIEW

2. WHY AN IND IS NEEDED - IMPORTANCE AND STUDY REQUIREMENT

A. Legal Requirement

B. Human Subject Protection

• Allow the study to proceed
• Place a clinical hold (partial or full) if safety concerns exist
• Request additional data

C. Preclinical to Clinical Bridge

1. Preclinical (nonclinical) studies - animal-based assessment of safety, toxicology (acute, sub-acute, chronic), pharmacokinetics (ADME), pharmacodynamics, reproductive toxicity, mutagenicity, and carcinogenicity
2. Clinical trials (Phases 1-4) - human-based evaluation of safety and efficacy

D. Regulatory Oversight Throughout Development

• Protocol amendments (changes to study design)
• Information amendments (new CMC, pharmacology-toxicology, or clinical data)
• IND safety reports (15-day expedited reports for serious unexpected adverse reactions)
• Annual progress reports (filed within 60 days of the annual IND date)

E. Ethical Obligations

3. CLASSIFICATION OF IND

A. By TYPE (Three IND Types)

B. By CATEGORY (Two IND Categories)

C. Special IND Designations

4. FORMAT OF THE IND APPLICATION (21 CFR § 312.23)

SECTION 1: Cover Sheet - FDA Form 1571

• Full name, address, and telephone number of the sponsor
• Date of application
• Name of the investigational new drug
• Identification of the phase(s) of clinical investigation to be conducted (Phase 1, 2, or 3)
• A commitment that the sponsor will not begin clinical investigations until the IND is in effect
• A commitment to conduct investigations in accordance with all applicable regulations
• Certification that the sponsor will notify the FDA of any adverse experience reports
• Signature of the sponsor or sponsor's authorized representative

SECTION 2: Table of Contents

SECTION 3: Introductory Statement and General Investigational Plan

• Brief description of the drug substance and drug product
• The drug's route of administration, dosage level(s), and duration of administration
• The type of investigation(s) to be conducted
• The general plan for clinical investigation (including phases, goals, number of subjects, safety monitoring)

SECTION 4: Investigator's Brochure (IB)

• Physical, chemical, and pharmaceutical properties and formulation
• Pharmacological and toxicological data obtained from animal studies
• Summary of human experience (if any prior human data exists)
• Brief statement of potential risks and side effects based on all prior experience
• Any precautions or special monitoring required

SECTION 5: Clinical Protocol(s) - FDA Form 1572

• Clear statement of the research question and hypothesis

• Name, address, and credentials of each investigator (Form FDA-1572 - Statement of Investigator)
• Name, address of IRB responsible for review

• Inclusion and exclusion criteria
• Age range, sex, and health status of subjects
• Number of subjects to be enrolled

• Phase designation (I, II, or III)
• Randomization and blinding methods
• Comparator arm (placebo, standard of care)

• Dose levels to be administered
• Method of administration
• Duration of individual subject participation

• Clinical observations to be made
• Laboratory tests to be performed
• Criteria for stopping the study (dose-limiting toxicity, stopping rules)

• Procedures for tabulating and analyzing data
• Primary and secondary endpoints

SECTION 6: Chemistry, Manufacturing, and Controls (CMC)

• Name, structural formula, and molecular weight
• Method of synthesis/manufacture
• Physical, chemical, and biological properties
• Stability data and storage conditions
• Purity, impurity profile, and analytical test methods

• Formulation composition (active ingredient, excipients)
• Dosage form and strength
• Container/closure system
• Manufacturing process and controls
• Release specifications and in-process controls

• All labels and labeling to be used for the investigational product

• Assessment of potential environmental impact (most products qualify for categorical exclusion)

SECTION 7: Pharmacology and Toxicology Information

• Mechanism of action
• Pharmacodynamic effects (receptor binding, downstream effects)
• Pharmacokinetics (ADME): absorption, distribution, metabolism, excretion
• Drug-drug interaction data

• Acute toxicity: Single-dose studies in at least two species; establishes LD50 and initial safety margins
• Subacute/Subchronic toxicity: Repeated-dose studies (14 days to 3 months) assessing target organ toxicity
• Chronic toxicity: Required for drugs intended for long-term human use (6 months to 2 years)
• Genotoxicity/Mutagenicity: Ames test, chromosomal aberration assay, in vivo micronucleus test
• Reproductive and developmental toxicity: Effects on fertility, embryo-fetal development (teratogenicity), postnatal development
• Carcinogenicity: Required if long-term use is intended; rat and mouse lifetime studies
• Local tolerance: Assessment at the intended route of administration

SECTION 8: Previous Human Experience (if any)

• Summary of all prior human use of the drug, whether from foreign studies, compassionate use, or unapproved marketed use
• Any published or unpublished results of prior human testing
• If the drug has been marketed elsewhere, information about those markets

SECTION 9: Additional Information

• Drug dependence and abuse potential (if applicable)
• Radioactivity data (if radioactively labeled drug)
• Pediatric considerations (if the drug will be tested in children)
• Special manufacturing requirements

KEY FDA FORMS IN THE IND

5. STUDY REQUIREMENTS CORRESPONDING TO IND PHASES

6. ONGOING IND OBLIGATIONS AFTER INITIAL SUBMISSION

1. 30-Day Review Window - No clinical trial begins until 30 days post-submission (or sooner if FDA clears it)
2. Protocol Amendments - Required before implementing any protocol changes
3. IND Safety Reports - Serious Unexpected Suspected Adverse Reactions (SUSARs) must be reported within 15 calendar days (7 days for fatal/life-threatening reactions)
4. Annual Reports - Filed within 60 days of the IND anniversary, including enrollment progress, safety summary, protocol status, and manufacturing changes
5. Information Amendments - New CMC, pharmacology/toxicology, or clinical data submitted as needed (but no more than every 30 days where feasible)

7. IND EXEMPTIONS

• A lawfully marketed drug is being studied under conditions of approved labeling (routine clinical practice)
• The study does not involve a route of administration, dose level, or patient population that significantly increases risk
• The investigation does not involve a new indication or purpose that requires demonstrating safety and effectiveness
• The study is not intended to support an NDA or IND application

8. SUMMARY DIAGRAM OF IND PROCESS

DISCOVERY & PRECLINICAL
        ↓
  Synthesize molecule → Animal pharmacology/toxicology → CMC development
        ↓
  PRE-IND MEETING WITH FDA (optional but recommended)
        ↓
  SUBMIT IND APPLICATION (Form 1571 + all sections)
        ↓
  FDA 30-DAY REVIEW
   ├── Approved → Begin Phase 1 Clinical Trial
   ├── Clinical Hold → Additional data required
   └── Disapproved → Cannot proceed
        ↓
  PHASES 1 → 2 → 3 (ongoing IND amendments/reports)
        ↓
  NDA / BLA SUBMISSION → Market Approval
        ↓
  PHASE 4 Post-Marketing Surveillance

9. KEY REGULATORY REFERENCES

• Goodman & Gilman's The Pharmacological Basis of Therapeutics (The IND Application section)
• Tietz Textbook of Laboratory Medicine, 7th Ed. (Drug Development, p. 385)
• U.S. Code of Federal Regulations, 21 CFR Part 312 (eCFR, 2025)
• FDA CBER: Submission of an IND to CBER
• PMC Article: Understanding FDA Regulatory Requirements for IND Applications - PMID 4435682