Track B7‑33 in Peptimes™
B7-33 is a peptide of 27 amino acids derived from the hormone relaxin, with no disulfide bonds. NLM's MeSH lists it as a supplementary substance mapped to relaxin. (Source: NLM MeSH.)
Is B7-33 FDA-approved?
No. B7-33 isn't FDA-approved, and Drugs@FDA lists no application with it as an active ingredient.
B7-33
Also: B7-33 peptide, H2 relaxin B7-33
- Status label in the Peptimes Library
- Not FDA-Approved
- Routes in Peptimes
- Subcutaneous
- Updated
- 1 Nov 2026
US regulatory status
What studies have looked at
Each point says who or what was studied and what the study reported, with its source and the date we checked it. These are findings from the sources cited, not advice or a promise of any result.
- In animals or the lab
In cells and in three rodent models of heart or lung disease, B7-33 prevented or reversed organ scarring (fibrosis) about as potently as relaxin-2. Unlike relaxin-2, it did not promote prostate tumour growth in mice.
Source: PMID 30155023, checked 1 Nov 2026
- In animals or the lab
In mice after a blocked coronary artery was reopened, B7-33 reduced the area of damaged heart muscle (about 22% vs 45% with vehicle) and preserved heart pumping function at 24 hours and 7 days.
Source: PMID 32295457, checked 1 Nov 2026
- In animals or the lab
In mice with drug-induced heart damage, B7-33 and relaxin reduced left ventricle scarring and inflammation about equally. Perindopril, studied as a comparison, lowered blood pressure but did not reduce scarring.
Source: PMID 36753958, checked 1 Nov 2026
How to track it in Peptimes
Add B7-33 in My Protocols and set the schedule you already follow: days of the week, times of day and a start date. Peptimes never suggests an amount when you log or schedule a dose. Its Library entry shows the status label “Not FDA-Approved”.
- Logging: the amount you took and how you feel.
- Injection sites: each dose records the site, and Insights shows where you’ve injected and how recently. It never suggests where to inject next.
- Reminders and history: reminders at your times, Dose History, the Calendar and CSV or JSON export work as described on the peptide tracker app page.
Peptimes is a tracking app, not medical advice. Talk to a licensed clinician about your treatment. Peptimes doesn’t sell B7-33 or any other compound.
More sources
- US National Library of Medicine, MeSH, B7-33 peptide, checked 1 Nov 2026: a 27-amino-acid peptide derived from relaxin, with no disulfide bonds.
- Medsafe (New Zealand’s medicines regulator), Classification of Unscheduled Peptides, June 2025, checked 1 Nov 2026: B7-33 does not appear to have been studied in human clinical trials.
- NIH, ClinicalTrials.gov, search for B7-33, checked 1 Nov 2026: no registered study.
- FDA, Drugs@FDA, checked 1 Nov 2026: no application lists B7-33 as an active ingredient.