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B7-33 (Relaxin) record · updated 18h ago

Healing & recoveryInflammation & immuneGrade A · human clinicalResearch use only
All 8 studiesJump to the evidenceCompare
What is B7-33 (Relaxin) used for?

B7-33 is a single-chain peptide analog of relaxin-2 designed to retain anti-fibrotic and vasodilatory signaling while simplifying synthesis. It is investigational and research-use only.

How it works: RXFP1 receptor agonist

Primarily researched for · Healing & recovery

Development stage

where B7-33 (Relaxin) sits between preclinical work and regulatory approval
  1. 1Cleared
    Preclinical
    Animal / in-vitro work
  2. 2Cleared
    Phase 1
    Safety in humans
  3. 3Current
    Phase 2
    Efficacy signal
  4. 4Not reached
    Phase 3
    Confirmatory trials
  5. 5Not reached
    Approved
    Cleared by a regulator

Stage is inferred from the highest trial phase in the indexed corpus and 10 registered trials. It describes the research record, not a recommendation.

Identity
NameB7-33 (Relaxin)
Chain length—
Molecular weight—
Formula—
Structure type—
ClassHealing
Research levelModerate Research
Discovered byCurated master list · 2026
Pharmacology
MechanismRXFP1 receptor agonist
Route—
Half-life—
Time to peak—
Duration—
Extraction confidence0.70
Effect profile · 0–5
These seven scores are generated by the Librarian — an autonomous agent running GPT-4o over the indexed studies, trials and label data for this compound. No human assigns them and no community vote moves them. Last recomputed Oct 13, 2026. How this works →
Research stats
Total studies8
Human / animal / cellular8 / 0 / 0
Highest trial phasePhase 2
Years covered2009–2026
Latest study4d ago
Publication history
20092026
Research funding
12 NIH projects · $4.3M awarded · through FY2026
Public grants naming this compound. Funding is interest, not evidence.
Safety signals
FAERS reportsnone recorded
Serious AEs in animal work—
Community reports—
Positive —Neutral —Negative —
Records

Study register

8 rowsOpen in the library →
StudyTypeYearSummary depth
Relaxin for the treatment of patients with acute heart failure (Pre-RELAX-AHF): a multicentre, randomised, placebo-controlled, parallel-group, dose-finding phase IIb study.
Finding40% of patients in the relaxin 30 microg/kg group moderately or markedly improved dyspnoea at 6 h, 12 h, and 24 h vs 23% in the placebo group, p=0.044.
Human2009Full text read0.80
Serelaxin, recombinant human relaxin-2, for treatment of acute heart failure (RELAX-AHF): a randomised, placebo-controlled trial.
FindingVAS AUC improvement of 448 mm × h, 95% CI 120-775; p=0·007 for serelaxin vs placebo.
Human2013Full text read0.85
Effects of Serelaxin in Patients with Acute Heart Failure.
FindingHazard ratio for death from cardiovascular causes was 0.98; 95% CI, 0.83 to 1.15; P = 0.77.
Human2019Full text read0.90
Heterozygous germline <i>MSH3</i> mutations, and probably <i>MLH3</i> mutations, act as classical tumour suppressors, leading to excess somatic deletion mutations, signature ID4 and increased colorectal cancer risk
Finding2.2-fold increased risk of CRC for heterozygous MSH3 mutations, P=6.6x10^-5
Human2026Full text read0.80
A conserved grain-associated immunosuppressive niche in Sudanese patients with mycetoma
FindingNot reported in abstract.
Human2026Full text read0.70
Sex-based considerations in the choice for a TLR9 or TLR7/8 agonist to arm the sentinel lymph node in early-stage melanoma.
FindingNot reported in abstract.
Human2026Full text read0.70
A relative methylation ordering biomarker of lactylation-related genes predicts prognosis and therapeutic response in cutaneous melanoma.
FindingKaplan-Meier log-rank test, p=0.046 for survival differences between clusters.
Human2026Full text read0.80
Pooled analysis of 2 clinical trials of first-line chemoimmunotherapy for metastatic microsatellite stable colorectal cancer MEDITREME and METIMMOX studies.
FindingMedian OS not reached vs 15.3 months; HR=0.58; 95% CI, 0.36-0.96; p=0.03.
Human2026Full text read0.80

What people are saying

anecdotal · not evidence

Unverified first-hand accounts from public forums. These are not studies: nobody checked what was taken, whether it was what the label said, or what else was going on. They count for nothing in the evidence grade above and are shown because a reader searching B7-33 (Relaxin) will meet them anyway, and meeting them next to a graded evidence base is better than meeting them alone.

Community collection has not run yet, so this is an empty shelf rather than a quiet one — nothing has been read, and no conclusion about how much B7-33 (Relaxin) is discussed should be drawn from it.