Getting a peptide drug into clinical trials requires a clear regulatory pathway. The Investigational New Drug (IND) application is the key step that allows you to test your peptide in humans.
The IND process can seem overwhelming, but breaking it down into simple steps makes it manageable. This guide walks you through everything you need to know.
- An IND application must be filed with the FDA before starting clinical trials in the U.S.
- The IND has three main sections: chemistry, nonclinical, and clinical
- The FDA has 30 days to review an IND before trials can begin
- Good planning and early FDA interactions can speed up the process
- Peptide drugs have some unique regulatory considerations compared to small molecules
What Is an IND Application?
An IND is a formal request to the FDA to begin testing a new drug in people. It provides the FDA with data showing that the drug is reasonably safe for initial testing.
The IND is not an approval to sell the drug. It is permission to conduct clinical trials under carefully controlled conditions.
The FDA receives over 2,000 new IND applications each year. Peptide drugs make up a growing share of these submissions as the peptide therapeutics market continues to expand.
When Do You Need an IND?
You need an IND before any human testing of your peptide drug in the United States. This includes Phase 1, Phase 2, and Phase 3 clinical trials.
There are some limited exceptions, such as investigator-initiated studies using already marketed drugs. But for new peptide compounds, an IND is always required.
The Three Main Sections of an IND
Every IND application has three main technical sections. Each section covers a different aspect of the drug and the proposed study.
Understanding what goes into each section helps you plan your development program efficiently. Here is an overview of the three sections.
| IND Section | What It Covers | Key Documents |
|---|---|---|
| Chemistry, Manufacturing, Controls (CMC) | Drug substance and product quality | Manufacturing process, specifications, stability data |
| Nonclinical | Animal and lab safety studies | Toxicology reports, pharmacology data |
| Clinical | Proposed human study design | Protocol, investigator brochure, informed consent |
Chemistry, Manufacturing, and Controls (CMC)
The CMC section describes how your peptide is made, tested, and stored. It must show that you can consistently produce a high quality product.
For peptide drugs, this section includes details about the synthesis method, purification process, analytical testing, and stability. The FDA wants to see that your peptide is well characterized and that your manufacturing process is under control.
Key CMC Requirements for Peptides
| Topic | What to Include |
|---|---|
| Drug substance | Synthesis route, structure confirmation, impurity profile |
| Drug product | Formulation, dosage form, container closure |
| Specifications | Acceptance criteria for identity, purity, potency |
| Stability | Data supporting the proposed shelf life |
| Reference standard | Characterization of the reference material |
Expert Quote: "The CMC section is where many peptide INDs stumble. Start your analytical method development early and invest in thorough characterization. The FDA expects a high level of detail for peptide drugs.", Dr. Robert Kim, Regulatory Affairs Consultant
Nonclinical Studies
The nonclinical section presents the results of your animal and laboratory studies. These studies must show that the peptide is reasonably safe to test in humans.
Required studies typically include pharmacology studies, toxicology studies in at least one relevant animal species, and sometimes safety pharmacology assessments. The scope depends on the type of peptide and the proposed clinical use.
Clinical Protocol
The clinical section describes the proposed human study. It includes the protocol, investigator brochure, and informed consent form.
The protocol must clearly state the study objectives, patient population, dose levels, endpoints, and safety monitoring plan. The investigator brochure summarizes all available information about the drug for the clinical team.
The IND Timeline
Planning your IND timeline is critical for staying on track. Most companies need 12 to 18 months to prepare an IND application from the time they have a candidate molecule.
Here is a typical timeline for a peptide drug IND. Your actual timeline may vary depending on the complexity of your program.
| Activity | Typical Timeline |
|---|---|
| Select lead peptide candidate | Month 0 |
| Begin GMP manufacturing | Month 2 to 4 |
| Start nonclinical studies | Month 3 to 6 |
| Develop analytical methods | Month 2 to 6 |
| Complete toxicology studies | Month 9 to 12 |
| Write IND application | Month 10 to 14 |
| Submit IND to FDA | Month 14 to 18 |
| FDA 30-day review period | 30 calendar days |
| Begin clinical trial | Month 15 to 19 |
Pre-IND Meeting With the FDA
Before filing your IND, you can request a pre-IND meeting with the FDA. This is a valuable opportunity to discuss your development plan and get feedback.
The FDA generally grants pre-IND meetings for novel drug candidates. Submit your meeting request with a briefing document that outlines your program and specific questions.
Companies that hold pre-IND meetings with the FDA are significantly more likely to have their IND accepted on the first submission. The feedback from these meetings helps avoid common mistakes.
Benefits of a Pre-IND Meeting
A pre-IND meeting lets you discuss your nonclinical study plans, CMC strategy, and clinical protocol design. The FDA's feedback can save you months of work and millions of dollars.
Prepare clear, specific questions for the meeting. Vague questions will get vague answers, so focus on the issues that matter most for your program.
Unique Considerations for Peptide INDs
Peptide drugs have some special regulatory considerations that differ from small molecule drugs. Understanding these helps you prepare a stronger application.
Peptides often have more complex manufacturing processes and more challenging stability profiles. The FDA expects detailed information about these aspects.
Impurity Profiling
Peptide synthesis can produce many related impurities, including deletion sequences, modification products, and racemized forms. The FDA expects thorough impurity identification and control.
Develop strong analytical methods that can detect and quantify all significant impurities. HPLC, LC-MS, and peptide mapping are commonly used techniques.
Immunogenicity Assessment
Peptide drugs can sometimes trigger immune responses in patients. The FDA may require you to assess the immunogenicity risk of your peptide.
Include an immunogenicity risk assessment in your IND. If your peptide is similar to a human protein, the risk may be lower, but it still needs to be evaluated.
Stability Challenges
Many peptides are sensitive to heat, light, and moisture. Your stability program must demonstrate that the drug product remains potent and pure throughout its shelf life.
Work with your manufacturing partner to develop a stable formulation early in development. Consider peptide storage requirements when designing your stability studies.
Common Reasons INDs Are Placed on Hold
The FDA can place an IND on clinical hold if they have safety concerns. This means you cannot begin or must stop your clinical trial until the issue is resolved.
According to the FDA's own data, the most common reasons for clinical holds include insufficient safety data, poor manufacturing controls, and inadequate clinical protocols. Being thorough in your application helps avoid holds.
How to Avoid Clinical Holds
| Common Hold Reason | How to Prevent It |
|---|---|
| Insufficient toxicology data | Follow FDA guidance documents for study design |
| CMC deficiencies | Invest in thorough characterization and process controls |
| Protocol safety concerns | Include strong safety monitoring and stopping rules |
| Inadequate informed consent | Have an experienced IRB review your consent form |
| Missing or incomplete information | Use FDA's IND template checklist |
Working With Regulatory Consultants
Many peptide companies hire regulatory consultants to help with their IND applications. A good consultant can guide you through the process and help avoid costly mistakes.
Look for consultants with specific experience in peptide or biologic drug INDs. General regulatory consultants may not understand the unique challenges of peptide development.
After the IND Is Accepted
Once the FDA accepts your IND, you can begin your clinical trial. But the regulatory work does not stop there.
You must submit annual reports, safety reports, and protocol amendments as needed. The IND remains active throughout the entire clinical development program until the drug is approved or the program ends.
Expert Quote: "Filing the IND is a milestone, not a finish line. Maintaining your IND in good standing requires ongoing communication with the FDA and prompt reporting of any safety signals.", Lisa Wang, VP of Regulatory Affairs
International Considerations
If you plan to run clinical trials outside the United States, you will need to file applications with other regulatory agencies. The requirements vary by country.
The European Medicines Agency (EMA) uses a Clinical Trial Application (CTA) process. Other countries have their own requirements that may differ from the FDA's IND process.
Frequently Asked Questions
How long does the FDA take to review an IND?
The FDA has 30 calendar days to review a new IND application. If they do not raise any concerns during that period, the IND goes into effect and you can begin your trial.
How much does it cost to prepare an IND for a peptide drug?
Total IND-enabling costs for a peptide drug typically range from $2 million to $10 million. This includes GMP manufacturing, nonclinical studies, analytical development, and regulatory writing.
Can I start manufacturing before the IND is filed?
Yes. In fact, you must manufacture your clinical trial material before filing the IND, since the CMC section requires data from your GMP batches. Start manufacturing early in your timeline.
What happens if the FDA places my IND on clinical hold?
You must address the FDA's concerns before resuming clinical activities. The FDA will issue a clinical hold letter explaining the specific issues. Once you respond adequately, they will lift the hold.
Do peptide drugs follow the same IND process as small molecule drugs?
The basic IND process is the same, but peptide drugs have unique CMC and nonclinical requirements. The FDA has specific guidance documents for peptide and protein therapeutics that you should follow closely.
Topics
Dr. Lisa Park
Regulatory Affairs Specialist
PharmD | 9 years in peptide pharmaceutical compliance
Focuses on FDA, DEA, and state pharmacy board regulations governing peptide compounds. Guides compounding pharmacies and peptide manufacturers through changing compliance landscapes.
Reviewed by Dr. Lisa Park, PharmD, April 2026