Evidence is not a single bucket. An FDA label, a peer-reviewed trial, a registered study record, and a community protocol page answer different questions and carry different limits.
The four labels PepPlanner uses
| Evidence type | What it can support | What it cannot prove by itself |
|---|---|---|
| FDA prescribing information | Approved indications, administration, warnings, contraindications, and current labeled regimen. | That the same regimen fits every person or every off-label use. |
| Published clinical trial | What a defined study tested, in whom, for how long, and what happened. | Regulatory approval or a universal treatment plan. |
| Registered clinical trial | A planned or ongoing study design, sponsor, status, arms, outcomes, and timing. | Successful results, publication, or approval. |
| Community research reference | Secondary context and terminology when clearly labeled. | An established human regimen, product quality, or clinical authority. |
1. FDA prescribing information
This is the highest authority tier used by PepPlanner for an approved drug. The label is product- and indication-specific. It includes far more than a starting value: warnings, contraindications, administration details, adverse reactions, use in specific populations, and revisions all matter.
The FDA explains that its review examines clinical evidence, side effects, manufacturing, and proposed labeling before approval. Read the agency's overview of the drug review process.
PepPlanner currently treats the FDA prescribing information for products such as Zepbound and Wegovy as approved-label sources. The app links to the current document rather than paraphrasing it as a generic class rule.
2. Published clinical trial
A published trial can be excellent primary evidence. It still describes a specific experiment: eligibility rules, randomized arms, target outcomes, duration, and statistical analysis. The tested regimen belongs to that design.
A useful reading pass asks: Was the study randomized? Was there a comparator? How many participants completed it? What was the primary endpoint? How long was follow-up? Were adverse events reported by arm? Who funded the work?
For example, the published Retatrutide phase 2 obesity trial tested several once-weekly study arms over 48 weeks. It supports describing those arms. It does not create an FDA-approved Retatrutide dose or one standard plan for the public. PepPlanner links the original New England Journal of Medicine report and marks the compound investigational.
3. Registered clinical trial
ClinicalTrials.gov records are valuable for seeing what a study plans to evaluate, which phase it is in, the sponsor, recruitment status, eligibility, endpoints, and whether results have been posted.
Registration is not publication and is not approval. Some records mask exact arm details, and some completed trials have no posted results yet. ClinicalTrials.gov provides a useful guide to reading a study record, including its status, NCT number, sponsor, results tab, and record history.
4. Community research reference
Community sources can help identify vocabulary or locate claims worth checking. They are not interchangeable with a regulator, manufacturer label, hospital, university, or primary paper. A polished chart does not upgrade the authority behind it.
PepPlanner keeps these references visibly separated. If no approved label or qualifying human trial supports a use, the app says so rather than borrowing the authority of a different product or indication.
Investigational does not mean secretly approved
Phase 2 or Phase 3 language can sound close to approval. It is still research. A later-phase trial may provide more evidence about efficacy and safety, but only the regulator can approve a product for a labeled indication.
The clean sentence is often the least exciting one: "This is a regimen tested in a clinical trial; the compound remains investigational and is not FDA-approved." That sentence preserves the useful study information without implying a prescription.
Fast red flags
- The source is described as "clinical" but no trial, label, DOI, or NCT number is linked.
- A study arm is rewritten as "the standard dose" without the study population or status.
- A secondary blog cites another secondary blog.
- Animal, cell, or mechanistic findings are presented as proven human outcomes.
- "FDA registered" or "made in an FDA facility" is used to imply that a product is FDA-approved.
- Product quality and regimen evidence are treated as the same question.
FDA states that compounded drugs are not FDA-approved and are not reviewed for safety, effectiveness, or quality before marketing. A study about an active ingredient does not establish the quality of an unrelated finished product. See Compounding and the FDA: Questions and Answers.
The bottom line
Good evidence reading starts by naming the source type before repeating the claim. PepPlanner's job is to keep that label attached all the way from the source card to the calculator, so a useful number never loses its context.