I'd like to know the process of drug approval; the flow from R&D, planning a clinical trial to drug approval, or other additional process.

As far as I am aware, some documents provide too much detail about a clinical trial's procedural flow, still, I could not find any documents that provide an overview of the entire process.

It may vary from country to country, but I'd like to know about the following, mainly for the US and Europe.

Can I understand the typical flow from planning to a clinical trial to approval to be as follows? If I'm wrong, please correct it.

Clinical trial's procedural flow (As I understand it.):

(1)Pre-clinical study:
Simulate the efficacy and safety of an investigational drug by in vivo studies.
(2) Pre IND consultation:
Consult with regulatory authorities to bring the clinical trial plan to an acceptable level. (Target Disease, Optimize dosage, number of subjects and endpoints, setting up observation periods, etc.)
(3) IND:
Submission of Clinical Trial Plan.
(4) Review of Clinical Trial Plans by Regulatory Authorities:
Regulatory Authorities determine the acceptance/rejection of the clinical trial plan.
(5) Conducting a Clinical Trial:
Patient Recruitment, FPI, ..., LPI, and data analysis.
(6)Pre-NDA/BLA consultation:
Pre-consultation to meet the requirements for the NDA/BLA.
Request to have regulatory authority's review to the investigational drug.
To obtain permission to sell it as a pharmaceutical product. Permission is granted to advocate that the product has specific medicinal properties.


1 Answer 1


I'm afraid it would be frowned you all if I answered it by myself and took my response as a solution, but... As I mentioned in the comments section above, I found a very summarized resource on the FDA's web site.

According to the FDA, Drug Review Steps Simplified is as follows.(This is a regular approve route. Not a shortcut-way.)


  1. Preclinical (animal) testing.
  2. An investigational new drug application (IND) outlines what the sponsor of a new drug proposes for human testing in clinical trials.
  3. Phase 1 studies (typically involve 20 to 80 people).
  4. Phase 2 studies (typically involve a few dozen to about 300 people).
  5. Phase 3 studies (typically involve several hundred to about 3,000 people).
  6. The pre-NDA period, just before a new drug application (NDA) is submitted. A common time for the FDA and drug sponsors to meet.
  7. Submission of an NDA is the formal step asking the FDA to consider a drug for marketing approval.
  8. After an NDA is received, the FDA has 60 days to decide whether to file it so it can be reviewed.
  9. If the FDA files the NDA, an FDA review team is assigned to evaluate the sponsor's research on the drug's safety and effectiveness.
  10. The FDA reviews information that goes on a drug's professional labeling (information on how to use the drug).
  11. The FDA inspects the facilities where the drug will be manufactured as part of the approval process.
  12. FDA reviewers will approve the application or issue a complete response letter.

Now that's a generally satisfactory answer.

While #1, #2, and ... describe "what action is to be taken", it is not clear who is to perform these action. However, #1 is likely to be a matter for the drug companies (sponcer) side. Perhaps the action should be taken by the sponsor, except for the step where the subject of the action is specified as the FDA (For example #8).

The #2 above is an explanation of the role of the document being reviewed, not "what action will be taken," but the reality is probably "the action will be that this document will be submitted at this step.

Also, although it's not specified in the Box above, I think you probably need to get permission to conduct a separate clinical trial for each of phase 1 to 3 (see #3 through #5 in the Box above). But, I don't have the rationale for that at the moment.

The Pre-IND Consultation described in the questions section also appears to be a real process in the US.

Note that, in addition to the INDs and NDAs mentioned in the Box above, the following types of drug applications that can be submitted to FDA.

  • Abbreviated New Drug Application (ANDA)
  • Biologic License Application (BLA)

Other FDA's resources have been narrowed down to five from BoxF1's (See Box F2); it omits typical administrative procedures, such as IND, NDA,... . On the other hand, it also contains an explanation of post marketing surveillance, which is not described in Box F1.

BoxF2 :

STEP1: Discovery and Development
Research for a new drug begins in the laboratory.
STEP2: Preclinical Research
Drugs undergo laboratory and animal testing to answer basic questions about safety.
STEP3: Clinical Research
Drugs are tested on people to make sure they are safe and effective.
STEP4: FDA Review
FDA review teams thoroughly examine all of the submitted data related to the drug or device and make a decision to approve or not to approve it.
STEP5: FDA Post-Market Safety Monitoring
FDA monitors all drug and device safety once products are available for use by the public.

I also found more detailed course designed for non expert .

The FDA has committees that advise on drugs, medical devices and regenerative medicine products. That is discussed in this Q&A.

For EMA, the followings are beneficial.

EMA's schema of Drug Review includes the followings (This is a regular approve route. Not a shortcut-way;


  • Scientific advice
    ・EMA can provide scientific advice to help medicine developers generate robust data on medicines.
    ・Developers ask specific questions about their plans to develop their medicine.
    ・EMA responds to the questions, often consulting additional experts and patients.
    ・EMA provides its advice, which is not binding either on EMA regarding future assessment of the medicine or on the developer, which can decide not to follow it.
  • Research & development
    ・Pharmaceutical and biotechnology companies, doctors and academics research new medicines.
  • Evaluation
    ・Developers apply for marketing authorization and submit data.
    ・EMA starts its assessment and prepares questions for the medicine developer.
    ・EMA often consults additional experts, healthcare professionals and patients.
    ・EMA recommends whether or not the medicine can be authorized for use in patients.
  • Authorization
    The European Commission takes a final decision on whether the medicine can be marketed in the EU
  • Access
    National and regional authorities decide on pricing and reimbursement.
  • Safety monitoring
    Once the medicine is authorized, EMA and national authorities continuously monitor its safety.

The European Medicines Agency (EMA) has following seven scientific committees.

  • Committee for Medicinal Products for Human Use (CHMP)
  • Pharmacovigilance Risk Assessment Committee (PRAC)
  • Committee for Medicinal Products for Veterinary Use (CVMP)
  • Committee for Orphan Medicinal Products (COMP)
  • Committee on Herbal Medicinal Products (HMPC)
  • Committee for Advanced Therapies (CAT)
  • Paediatric Committee (PDCO)

According to the EMA's site, committees and working parties also contribute to the development of medicines and medicine regulation, by the followings;

Box E2

  • providing scientific advice to companies researching and developing new medicines;
  • preparing scientific guidelines and regulatory guidance to help pharmaceutical companies prepare marketing authorisation applications;
  • contributing to the harmonisation of regulatory requirements n the EU and internationally.

Medical devices in Europe seem to be CE-mark based, but now it's in the middle of the confusion. I don't understand this, so I'd like to split the question separately.

  • 1
    Answering your own question isn't frowned upon on any SE site. It's perfectly fine to do so.,
    – Carey Gregory
    Commented Oct 22, 2020 at 3:55
  • @CareyGregory Thank you for your kind comment. Commented Oct 22, 2020 at 3:58
  • 1
    @BlueVarious You might want to add a little bit about Phase IV clinical trials to your answer. Phase IV clinical trials are not described in the "simplified" version of the flow for study approval but they can be an very important part of the post-approval assessment of FDA-regulated products. Commented Oct 22, 2020 at 16:53
  • @Diana Petitti Thanks for your comment, I'll look into Postmarketing surveillance as well. en.wikipedia.org/wiki/Postmarketing_surveillance Commented Oct 23, 2020 at 0:08

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.