Fexapotide
A single prostate injection designed to shrink the gland
Fexapotide triflutate is a synthetic 17-amino-acid peptide that is injected once into the prostate, through the rectum under ultrasound guidance, in a clinic visit lasting minutes. It makes prostate gland cells die by apoptosis. Long-term follow-up of two placebo-controlled phase 3 trials reported fewer surgeries and urinary retention episodes in men with benign prostatic hyperplasia. It is not approved.
What is it?
Benign prostatic hyperplasia, the non-cancerous enlargement of the prostate, causes urinary symptoms in many older men. Treatment usually starts with daily tablets and can end in surgery. Fexapotide was developed by Nymox as a third option: a single injection into the gland itself. In rats, injected fexapotide caused prostate glandular cells to die by apoptosis within one to three days and led to near-total loss of glandular tissue by six to twelve months, without damaging the nerves, vessels or connective tissue around them.
The main human evidence is two placebo-controlled, double-blind phase 3 trials in 995 men at 72 US sites, randomised 3 to 2 to fexapotide 2.5 mg or placebo, with follow-up of 2 to 6.75 years. The published report gives long-term results: symptom scores improved more with fexapotide (median 5.2 against 3.0 points), acute urinary retention and later prostate cancer were less frequent, and men who crossed over to fexapotide needed surgery less often than those who switched to tablets (8.1% against 27.9% at three years). Safety did not differ from placebo. The abstract does not state the 12-month primary endpoint result.
The same injection was tested in Grade Group 1 prostate cancer, the lowest-risk form usually managed by watching it. In 146 men randomised to 2.5 mg, 15 mg or active surveillance, a single injection reduced progression to treatment over four years, more so at 15 mg, with no drug-related serious adverse events.
Several authors of these trials disclosed consulting for, or shares in, Nymox. A 2014 independent review judged the treatment experimental on small numbers. Fexapotide has not been approved.
At a Glance
Every value in this table is printed from the Grey Peptides dataset, the same record the compound explorer and comparison tool read, so the three can never disagree.
Educational information, not medical advice. The doses on this page come from approved labels, published studies and, where no study exists, amounts reported by users. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose. Full medical disclaimer.
Published Research
Studies of fexapotide, from their PubMed abstracts.
Long-term phase 3 BPH trials
In 995 men (3:2 fexapotide 2.5 mg:placebo; follow-up mean 3.58 years), long-term symptom improvement was greater (median -5.2 vs -3.0, p < 0.0001); acute urinary retention and prostate cancer incidence were lower; BPH intervention at 3 years was 8.08% vs 27.85% for oral medication crossover; no significant safety differences.
Grade Group 1 prostate cancer
In 146 men randomised to 2.5 mg, 15 mg or active surveillance, a single injection significantly reduced progression to intervention over 4 years, with 15 mg superior to 2.5 mg and no drug-related serious adverse events.
Selective ablation in rats
In 371 rats, intraprostatic fexapotide caused glandular cell apoptosis within 24-72 hours and near-total loss of glandular epithelium at 6-12 months, sparing periprostatic nerves, vessels and stroma.
Review of the trial programme
More than 1,700 fexapotide and control injections in randomised blinded trials were reviewed; long-term US studies reported symptom improvement and fewer retention episodes and surgeries; all three authors disclosed Nymox consulting.
Independent evidence review
NX1207 reduced prostate volume and improved symptoms, but patient numbers were still low and treatment was still experimental.
Cost-effectiveness model
A Medicare-perspective model found fexapotide about as cost-effective as initial tablets at up to $14,000 per injection with a $150,000 per QALY threshold; one author disclosed Nymox consulting and shares.
Side Effects & Contraindications
Reported Side Effects
From the trials above.
Contraindications & Cautions
There is no label.
Legal Status
Fexapotide is investigational.
Frequently Asked Questions
?What is fexapotide?
An investigational 17-amino-acid peptide injected once into the prostate under ultrasound guidance. It causes prostate gland cells to die, aiming to shrink an enlarged prostate.
?Does fexapotide work for an enlarged prostate?
Long-term follow-up of two placebo-controlled phase 3 trials reported better symptom scores and fewer surgeries and urinary retention episodes. The trials involved investigators with financial ties to the developer, and the 12-month primary result is not given in the published abstract.
?Is fexapotide approved?
No. It has no FDA approval in Drugs@FDA as of October 3, 2026.
?Is it used for prostate cancer?
It was tested in Grade Group 1 prostate cancer, where a single injection reduced progression to treatment over four years compared with active surveillance. It is not approved for that either.
References
- [other] PubChem CID 16207730, Fexapotide: formula C90H163N27O25S, molecular weight 2055.5. Read October 3, 2026. https://pubchem.ncbi.nlm.nih.gov/compound/16207730
- [fda] FDA. Drugs@FDA (openFDA): no application on record for fexapotide. Read October 3, 2026.
- [registry] ClinicalTrials.gov API v2, read October 3, 2026: NCT00918983 and NCT00945490 (phase 3 BPH, 500 each, completed), NCT01438775 and NCT01846793 (phase 3 re-injection, 192 and 160, completed), NCT02003742 (phase 3, 104, terminated), NCT01620515 (phase 2 low-risk prostate cancer, 141, completed).
- [clinical-trial] Shore N, et al. "Fexapotide triflutate: results of long-term safety and efficacy trials of a novel injectable therapy for symptomatic prostate enlargement." World J Urol, 2018;36(5):801-809. PMID: 29380128.
- [clinical-trial] Shore N, et al. "Prospective evaluation of fexapotide triflutate injection treatment of Grade Group 1 prostate cancer: 4-year results." World J Urol, 2020;38(12):3101-3111. PMID: 32088746.
- [pubmed] Averback P, et al. "Fexapotide Triflutate Induces Selective Prostate Glandular Pharmaco-Ablation in the Rat." Res Rep Urol, 2019;11:343-350. PMID: 31909043.
- [pubmed] Shore N, et al. "Efficacy and safety of fexapotide triflutate in outpatient medical treatment of male lower urinary tract symptoms associated with benign prostatic hyperplasia." Ther Adv Urol, 2019;11:1756287218820807. PMID: 30719081.
- [pubmed] Kunit T, et al. "An evidence-based review of NX1207 and its potential in the treatment of benign prostatic hyperplasia." Res Rep Urol, 2014;6:67-70. PMID: 25157337.
- [pubmed] Wei Y, et al. "Fexapotide triflutate vs oral pharmacotherapy as initial therapy for moderate-to-severe benign prostate hyperplasia patients: a cost-effectiveness analysis." BMC Urol, 2022;22(1):76. PMID: 35550071.
Sources & Citations
Studies were read from their PubMed records and trial registrations from ClinicalTrials.gov, October 3, 2026.
Medical Disclaimer: This content is for educational and informational purposes only. It is not medical advice, and nothing here is an instruction to obtain or use any compound. Consult a licensed healthcare provider before making health decisions.