Clinical trial phases are the stages a medicine passes through between the laboratory and approval. This explainer covers each phase, the accelerated route, and where a few catalogue compounds actually sit.

Often, news about peptides mentions a phase. One compound is “in phase 3”, another “had a phase 1 study”, and a third has “approval”. Those words carry precise meanings, and they say a great deal about how much human evidence exists.

This article sets out the standard sequence as the US Food and Drug Administration describes it. Then it places three compounds from the SHLabz range on that map, using primary sources for each status. It describes regulatory stages only, and says nothing about what any compound does.

Quick answer: The clinical trial phases run in order. Preclinical lab and animal work comes first, then phase 1 in a small group of people, phase 2 in up to several hundred, and phase 3 in up to 3,000. A regulator then reviews the data and may approve the medicine for one use. Phase 4 studies follow approval. Each step filters out candidates, so “in a trial” never means “approved”.

Before the First Phase

First, every development programme starts in the laboratory. Preclinical research covers cell work and animal studies, and its job is to decide whether a compound should move into people at all.

The FDA states that these studies are usually not very large. Even so, they must give detailed information on toxicity before anyone moves on. The agency also requires researchers to follow good laboratory practice, a set of minimum standards for how such studies run, who staffs them and which facilities they use.

Accordingly, a compound with only preclinical data has no human trial record behind it. That is the position of much of the research peptide literature, and it is worth naming plainly when reading any claim.

The IND Gate

Next comes paperwork. In the US, a developer files an investigational new drug application, or IND, before the first study in people. According to the FDA, it includes animal and toxicity data, manufacturing information, the clinical study plans, any prior human data and details of the investigator.

The FDA review team then has 30 days to review the original submission. Only after that gate do the clinical trial phases begin.

Early Phase 1: A Step Before the Clinical Trial Phases

Some programmes add a very small study at the start. ClinicalTrials.gov labels these “Early Phase 1”, formerly listed as Phase 0. The NIH’s NCATS toolkit describes them as exploratory trials run before traditional phase 1 work.

In other words, they look at how or whether a drug affects the body. They involve very limited human exposure, and they have no therapeutic or diagnostic goals. So an “early phase 1” label marks the very start of human research, not a midpoint.

Clinical Trial Phases 1 to 3

Next, the FDA describes three phases before a marketing application. Each one is larger and longer than the last, and each one filters out a share of candidates.

• Phase 1. Typically 20 to 100 healthy volunteers or people with the condition, over several months. According to the FDA, about 70% of drugs move on to the next phase.
• Phase 2. Up to several hundred people with the condition, over several months to two years. The focus is efficacy and side effects, and about 33% of drugs move on.
• Phase 3. Usually 300 to 3,000 volunteers, over one to four years. These trials look at efficacy and monitor adverse reactions, and about 25–30% of drugs move on.

Those percentages also compound across the clinical trial phases. Consequently, “in phase 2” is a long way from “approved”, even though both phrases appear in the same kind of headline.

Some records also carry a combined label, such as “Phase 1/Phase 2”. That marks a single trial that combines phases 1 and 2. Still, the record itself is the place to check what the study actually measured.

How Trials Limit Bias

Size is not the only difference between the clinical trial phases. When researchers plan a study, the FDA says they decide whether there will be a control group and what other ways they will use to limit bias.

Late-stage trials usually use the strictest designs. For example, Lilly describes its retatrutide trial TRIUMPH-1 as a phase 3, 80-week, randomised, double-blind, placebo-controlled trial that randomised 2,339 participants. Randomised means chance decides who gets what. Double-blind means neither participants nor investigators know, and a placebo arm gives a fair comparison.

Phase 4 and Approval

After the regulator reviews the full data package, it decides whether to approve the medicine for a specific use. Approval is tied to that use, that formulation and that manufacturer. It does not extend to any other source of the same molecule.

Before filing, the FDA says a developer must have adequate data from two large, controlled clinical trials. That is why phase 3 programmes usually include several studies rather than one.

Phase 4 then follows approval. The FDA describes these studies as involving several thousand volunteers, and they continue to gather data once the medicine is in wider use.

The Accelerated Approval Route

For serious conditions with an unmet need, the FDA runs an accelerated approval programme. It allows earlier approval based on a surrogate endpoint. The agency defines that as a marker thought to predict a clinical result but not itself a measure of one.

However, the route carries a condition. Companies must still run confirmatory studies, and if those fail, the FDA has procedures that could lead to removing the drug from the market. An accelerated approval is therefore real but provisional.

Where Catalogue Compounds Sit on the Clinical Trial Phases

Retatrutide. Retatrutide, which SHLabz lists as SH-R, is investigational. As such, it holds no marketing authorisation anywhere. In its second-quarter 2026 results, Eli Lilly reported further positive phase 3 trials, called its clinical data package complete, and said it planned an FDA submission in the first quarter of 2027.

Elamipretide (SS-31). On 19 September 2025, the FDA granted accelerated approval to Forzinity, an elamipretide injection, for Barth syndrome. The approval rests on a surrogate measure, and the FDA requires a randomised, double-blind, placebo-controlled confirmatory trial. That medicine is a specific approved product. Research-grade SS-31 is not that medicine.

BPC-157. According to a 2025 literature and patent review, a phase 1 study of BPC-157 began in 2015 with 42 healthy volunteers. In 2016, however, the researchers cancelled submission of the results. No controlled human data have appeared since.

Beyond these three, many catalogue compounds rest mainly on cell and animal work. Each single-compound guide in our library states what exists for that compound.

What Regulators in the Region Have Said

Progress through the clinical trial phases abroad changes nothing locally. In July 2026, the Emirates Drug Establishment acted against 71 sources selling unapproved peptide products and referred 14 influencers. According to Gulf News, it said retatrutide remains under clinical investigation and is not approved for marketing or medical use in the UAE.

Neighbouring regulators have moved too. On 27 August 2026, The Peninsula reported a Qatar Ministry of Public Health circular banning the import, trade, use and promotion of unlicensed peptide preparations. It named retatrutide and BPC-157, and a “research use” label gives no exemption when someone promotes a product for human use. Then, on 29 September 2026, the Saudi Food and Drug Authority took legal action against online stores marketing unregistered peptides.

Checking Clinical Trial Phases on a Trial Record

Generally, registered trials carry an NCT number on ClinicalTrials.gov. Before trusting a summary, open the record and check four things: the phase, the recruitment status, whether results have been posted, and the sponsor. A registered trial with no posted results, as the BPC-157 example shows, adds little evidence.

A few more fields repay attention. The design section shows whether the study was randomised, masked and placebo-controlled. The enrolment figure shows how many people took part, and it lets you place the study against the FDA’s phase ranges. Meanwhile, the condition field shows what the trial studied, which may differ from what a headline implies.

Finally, compare dates. A study that finished years ago with nothing posted tells a different story from one that is still recruiting.

What a Certificate Can and Cannot Tell You

A certificate of analysis answers a narrower question than a trial does. It describes one batch of material: its identity by mass, its purity by HPLC and, sometimes, its measured content. Our certificate guide walks through each field.

For example, the SH-R 10 mg certificate on our lab results page covers batch SHRT10-082026, with an HPLC purity of 99.745% and measured content of 11.18 mg. The BPC-157 10 mg certificate covers batch BC10/2026-0310, at 99.764% purity and 9.72 mg content. SHLabz has not yet published a certificate for SS-31.

By contrast, a certificate says nothing about clinical status. A high purity figure does not move a compound up a phase. Similarly, the material in a trial is not the same thing as research material. The FDA’s IND file includes manufacturing information for the trial product itself, so a research vial cannot borrow a trial’s standing.

A Checklist for Clinical Trial Phases Claims

When a page or post mentions a phase, a short routine helps:

1. First, find the NCT number. If nobody gives one, treat the claim as unsupported until you find the record.
2. Second, confirm the phase on the record itself, not in a summary.
3. Next, check the recruitment status and whether results appear on the record.
4. Then note the sponsor and the condition studied.
5. After that, read the design: randomised, masked, placebo-controlled or open-label.
6. Also check the enrolment figure against the typical size for that phase.
7. Finally, separate the trial product from any research material. A certificate documents a batch, while approval belongs to one manufacturer’s product.

Where SHLabz Fits

SHLabz supplies every compound strictly as a laboratory research material, not for human use in the UAE or anywhere else. That includes SH-R, SS-31 and BPC-157. An independent laboratory tests every batch, and the certificates for SH-R and BPC-157 are on the lab results page.

The Short Version

In short, clinical trial phases run from small phase 1 studies through larger phase 2 and phase 3 trials to approval and phase 4. Each step filters out candidates, and accelerated approval remains provisional until confirmatory trials report.

Meanwhile, catalogue compounds sit at very different points. Retatrutide is in late-stage development, elamipretide holds an FDA accelerated approval as Forzinity, and BPC-157 has no published human trial results.

Frequently Asked Questions

What are the clinical trial phases? Phase 1 is a small first study in people, phase 2 is larger and looks at efficacy and side effects, and phase 3 is larger again. Phase 4 follows approval.

How many drugs make it through? The FDA estimates that about 70% move from phase 1 to phase 2, about 33% from phase 2 to phase 3, and about 25–30% beyond phase 3.

What is phase 0? ClinicalTrials.gov now calls it Early Phase 1. These exploratory studies come before phase 1, involve very limited exposure and have no therapeutic or diagnostic goals.

Is retatrutide approved? No. It is investigational, and Lilly has said it plans an FDA submission in the first quarter of 2027.

Is SS-31 an approved medicine? Elamipretide holds FDA accelerated approval as Forzinity for Barth syndrome. Research-grade SS-31 is a laboratory material, not that approved product.

What is a surrogate endpoint? It is a marker, such as a lab value or physical sign, that is thought to predict a clinical result. Accelerated approvals rely on one and require confirmatory trials.

Does a high purity result mean a compound is approved? No. A certificate describes one batch’s identity and purity. Approval comes from a regulator’s review of trial data for one specific product.

References

• Step 3: Clinical Research — US Food and Drug Administration. Participant numbers, durations and progression rates for phases 1 to 4.
• Accelerated Approval Program — US Food and Drug Administration. Surrogate endpoints, confirmatory studies and possible removal from the market.
• FDA Grants Accelerated Approval to First Treatment for Barth Syndrome — US Food and Drug Administration, 19 September 2025. Forzinity (elamipretide) and the required confirmatory trial.
• Lilly Second-Quarter 2026 Financial Results — Eli Lilly and Company, filed with the SEC, August 2026. Retatrutide phase 3 status and planned FDA submission.
• Multifunctionality and Possible Medical Application of the BPC 157 Peptide — Literature and Patent Review — Józwiak et al., Pharmaceuticals, 2025. The 2015 phase 1 study and its cancelled results.

Regulation in this area moves quickly. This article offers general information rather than legal advice, so anyone making a procurement decision with legal consequences should confirm the current position independently.

Finally, if you want to see each compound’s format and price, the catalogue lists the full research range.

This article is provided for general research and educational purposes only. All SHLabz products are sold strictly for laboratory research use and are not intended for human or veterinary consumption, diagnosis, treatment, or prevention of any disease. Nothing in this article constitutes medical advice. Always consult a qualified professional and comply with applicable local regulations regarding the handling and use of research compounds.