Edratide
A peptide copied from a lupus autoantibody, meant to retrain the immune response; safe in a 340-patient phase 2, but it missed its main goals
Edratide, also called hCDR1, is a synthetic peptide whose sequence comes from the first complementarity-determining region of a human antibody against DNA, the kind of autoantibody that drives systemic lupus erythematosus. The idea was to use a piece of the disease's own antibody to calm the T cells that help make it. In lupus-prone mice and in cells from patients it lowered inflammatory signals and raised regulatory T cells. In a 340-patient phase 2 trial run by Teva, weekly injections were safe, but the trial's main disease-activity endpoints were not met. It was never approved.
Used in human trials: 0.5, 1.0 or 2.5 mg, Once weekly, Subcutaneous (Study: PRELUDE phase 2, active systemic lupus (three dose arms vs p...) Details ↓
Recommended Dosing
Used in human trials
No manufacturer dose exists for this use: these are amounts given in published trials, not recommendations.
Work out syringe units → · New to syringes? · All dosing data ↓
What is it?
In systemic lupus erythematosus the immune system makes antibodies against the body's own DNA and other nuclear material. One line of research studied a human anti-DNA antibody carrying a shared marker called the 16/6 idiotype. Immunising mice with that antibody gave them a lupus-like disease. The researchers then made a short peptide from the antibody's first complementarity-determining region (CDR1), the loop that helps it bind its target, and called it hCDR1. Unlike the whole antibody, the peptide did not cause disease, and the plan was to use it to switch off the T cells that react to that region.
In mice it did what was hoped. Ten weekly injections eased established lupus in two mouse models, lowering anti-DNA antibodies, protein in the urine and kidney damage. It reduced the inflammatory cytokines interferon-gamma, interleukin-1-beta and interleukin-10 and raised the calming cytokine TGF-beta. Later papers from the group linked its effects to regulatory T cells, to lower BAFF (the B-cell survival factor targeted by the lupus drug belimumab), and to less brain inflammation and better behaviour in lupus mice. It also helped mice carrying blood cells from lupus patients, and pigs given an induced lupus-like disease.
The same group tested it in human cells. Added to blood cells from lupus patients, but not to cells from healthy donors, it lowered the same inflammatory genes and increased regulatory T cells. In a small placebo-controlled study, five patients treated for about six months showed lower expression of those genes, of interferon-alpha and of the immune enzyme IDO in their blood, along with lower disease-activity scores. Almost all of this work comes from the laboratory that designed the peptide.
The decisive test was the phase 2 PRELUDE trial, sponsored by Teva and registered as NCT00203151. It enrolled 340 patients with active lupus, mostly involving joints, skin and blood, and gave weekly injections of 0.5, 1.0 or 2.5 mg or placebo. Edratide was safe and well tolerated, but its two primary endpoints, both based on the SLEDAI-2K disease-activity score, were not met. A secondary endpoint, the BILAG response index, was met in the lowest-dose group, and the authors pointed to subgroups and trends. A 2012 review counts the hCDR1 trials among those that failed.
No phase 3 trial followed. ClinicalTrials.gov lists the phase 2 study as terminated, and no regulator lists edratide. The dose row below gives the amounts used in that trial, not a treatment anyone can be prescribed.
Mechanism of Action
Edratide is meant to induce tolerance: as a piece of a disease-driving antibody, it targets the T cells that respond to that antibody and shifts the immune response toward regulation. The evidence comes almost entirely from mice and from patients' cells.
Regulatory T cells
Raises TGF-beta and FoxP3-expressing regulatory T cells in patients' blood cells (PMID 19280712) and in treated patients (PMID 19346102).
Inflammatory cytokines
Lowers IL-1-beta, interferon-gamma, IL-10 and interferon-alpha expression in patients' blood cells and treated patients (PMIDs 19280712, 23555966).
B-cell survival
Lowered expression of BLyS (BAFF), the B-cell survival factor, in treated patients (PMID 19346102).
Published Research
These are studies of hCDR1 (edratide) itself, read from their PubMed abstracts: the phase 2 trial, small treated-patient studies of gene expression, studies of patients' blood cells in the dish, the mouse, pig and humanised-mouse work, and reviews. Nearly all come from the group that designed it. Studies of other lupus peptides, such as the mouse CDR1 peptide or P140, are not carded here.
PRELUDE phase 2: primary endpoints missed
340 patients with active lupus (SLEDAI-2K 6 to 12), mostly with joint, skin and blood involvement, received weekly subcutaneous edratide at 0.5, 1.0 or 2.5 mg or placebo. It was safe and well tolerated. Neither co-primary endpoint, both built on SLEDAI-2K, was met. The secondary BILAG endpoint was met at 0.5 mg (odds ratio 2.09) with trends at the higher doses, and post hoc subgroups pointed the same way.
Gene expression in treated patients
In 9 lupus patients treated for 26 weeks, the 5 given hCDR1 had lower blood-cell expression of IL-1-beta, TNF-alpha, interferon-gamma, IL-10, BLyS and two pro-apoptotic caspases, and higher TGF-beta and FoxP3. Their SLEDAI-2K fell from 8.0 to 4.4 and BILAG from 8.2 to 3.6. The 4 placebo patients were the comparison.
Lower interferon-alpha
In lupus mice, hCDR1 cut spleen interferon-alpha expression by 73%. In blood cells of 10 lupus patients in the dish it cut it by 74%, with no effect on cells of healthy people or antiphospholipid syndrome patients. In 5 patients treated weekly for 24 weeks, interferon-alpha expression fell 64% from baseline; none fell in the 4 on placebo.
Lower IDO in mice and patients
hCDR1 lowered expression of indoleamine-2,3-dioxygenase, an immune-regulating enzyme raised in lupus, in lupus mice, in patients treated with it and in patients' blood cells in the dish, but not in healthy donors or with a control peptide. The authors concluded its regulatory T cells do not depend on IDO.
Patients' blood cells in the dish
Blood cells from 11 lupus patients cultured with hCDR1 showed less IL-1-beta, interferon-gamma and IL-10, less of the pro-apoptotic caspase-3 and more of the protective Bcl-xL, and more TGF-beta, FoxP3 and regulatory T cells. Cells from 5 healthy controls, or cells given a control peptide, did not respond; blocking CD25 removed the regulatory effect.
Sjögren's syndrome cells
In blood cells from 16 patients with primary Sjögren's syndrome, hCDR1 but not a control peptide lowered IL-1-beta, TNF-alpha, MX-1 and BLyS and raised TGF-beta, FOXP3 and IDO. It had no effect on cells from rheumatoid arthritis or antiphospholipid syndrome patients.
Gene expression in lupus mice
Microarrays of spleen cells showed many genes changed in lupus-prone mice with established disease; treatment with edratide brought about 22% of them back to the levels of young healthy mice, including OX40 ligand, which also fell in the kidneys.
Its developers' summary
Its developers summarise hCDR1's effects in mouse lupus (kidney, serology and brain), its effects on cytokines, regulatory T cells, apoptosis and BAFF, and the gene changes and clinical improvement in treated patients, and presents it as a candidate disease-specific treatment.
Dosing Data
Edratide was never approved. These are the weekly amounts given in its 340-patient phase 2 trial, as stated in the published abstract and the registry record; the trial's primary endpoints were not met.
Educational information, not medical advice. Each dose above is tagged with its source: an approved label, a published human study, animal data, or 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.
What a Buyer Needs to Know
What is sold, how it is mixed, stored and taken, and what is known about its safety, quality and legal status. Each part names its source. Where we have none, it says unknown.
What is sold
Unknown: we hold no label and no published test that says what forms or vial sizes Edratide is sold in. A vial's own label is a seller's claim, not a source.
Mixing a vial: a worked example
An arithmetic example, not a recommendation: a 5 mg vial mixed with 2 mL of bacteriostatic water holds 2,500 mcg per mL, so every 10 units on a U-100 insulin syringe hold 250 mcg. 0.5 mg, the first amount in the “Study: PRELUDE phase 2, active systemic lupus (three dose arms vs placebo)” row (0.5, 1.0 or 2.5 mg) is 20.0 units (0.200 mL). If your vial or water differ, the numbers change: use the reconstitution calculator.
Source: dose: Used in human trials, PMID 26301100 (Dosing Data below); vial and water: the calculator's default example, not a vial size we have a source for.
Storage before and after mixing
Unknown: no label or published stability study on file says how to store Edratide, before or after mixing. The mixing guide sets out the general rules, with their sources: keep a mixed vial in the fridge, and use it promptly, as the bacteriostatic water label says of any drug dissolved in it. The 28 days often quoted is the limit for an opened multiple-dose vial from a manufacturer, an outer limit set for sterility, not a time a mixed solution has been shown to keep. Nobody has published how long Edratide stays intact once mixed.
How it is taken
As it was given in human studies: Subcutaneous (Once weekly; Study: PRELUDE phase 2, active systemic lupus (three dose arms vs placebo)).
For injection technique, sites and needle disposal, see the mixing guide.
Source: Used in human trials: the route and frequency of each row in Dosing Data below.
What to expect, and when
How long it stays in the body: not established by a measurement cited on this entry.
How long the doses were given: Study: PRELUDE phase 2, active systemic lupus (three dose arms vs placebo): Primary outcome assessed at 30 weeks (ClinicalTrials.gov NCT00203151).
When effects appear: unknown; no source on this page gives a time to effect for Edratide. Results reported in the studies are under Published Research.
Source: Used in human trials, the duration of each row in Dosing Data below.
Side effects, and when to stop or get help
From the Side Effects section: Safe and well tolerated at all three doses in the 340-patient phase 2 trial (PMID 26301100); The published abstracts list no specific side effects; injection-site and other events are not described there; Long-term safety beyond the trial period is unknown. Full list and cautions ↓
When to stop or get help: unknown; no label or trial on file sets rules for stopping Edratide. Treat a severe or unexpected reaction as a reason to stop and see a doctor.
Source: the Side Effects section below (“From the phase 2 trial and the small treated-patient studies”).
Interactions
Unknown: a PubMed search for human interaction studies of Edratide (reviewed 2026-10-28) found none. Unknown is not the same as safe to combine.
Every peptide's record, with its source: the interaction matrix.
Checking what you bought
Unknown: no published independent test of Edratide products is in our lab-results database yet, so how products sold under this name measure up is not known.
To read a certificate of analysis, paste it into the COA decoder; it checks the measured mass against Edratide's expected mass, 2,309.5 Da, from this entry's molecular data. Trust & Verification explains what independent testing can and cannot show.
Legal status
US: Not FDA Approved (Not approved anywhere we found: Drugs@FDA holds no record (searched October 28, 2026) and the EMA medicines list holds none (downloaded October 29, 2026)). Sport: Prohibited (S0 catch-all).
Country by country ↓ · Regulatory tracker
Source: this entry's approval status and the WADA Prohibited List, as in Legal Status below.
Side Effects & Contraindications
Reported Side Effects
From the phase 2 trial and the small treated-patient studies. The published abstracts report safety only in general terms, so specific side effects and their rates cannot be given here.
Contraindications & Cautions
No product label exists. These cautions follow from the evidence.
Legal Status
Edratide reached phase 2 in lupus and was never approved.
Frequently Asked Questions
?What is edratide?
A synthetic peptide, also called hCDR1, copied from the first complementarity-determining region of a human antibody against DNA. It was designed to make the immune system tolerate that antibody region in lupus.
?Did edratide work in lupus?
Not on its main measures. In a 340-patient phase 2 trial the two SLEDAI-2K-based primary endpoints were not met. A secondary measure, BILAG response, was met at the lowest dose.
?Was it safe?
In the phase 2 trial it was reported safe and well tolerated at weekly doses up to 2.5 mg. Long-term safety was not studied.
?Why do the early results look stronger?
The early human results come from small studies, five treated patients against four on placebo, measuring blood-cell gene expression, mostly from the laboratory that designed the peptide. The larger trial did not confirm a clear benefit.
?Is edratide approved anywhere?
No. No phase 3 trial followed, and no drug regulator lists it.
?Was edratide tested in any disease other than lupus?
Only in the laboratory. Blood cells from 16 people with primary Sjögren's syndrome responded to it in the dish, with lower inflammatory genes and higher regulatory markers, but no trial in Sjögren's syndrome followed.
?What did the treated-patient studies actually measure?
Gene expression in blood cells. Five patients given edratide for about six months had lower interferon-alpha, IL-1-beta, TNF-alpha and BLyS expression and lower disease scores than before, against four on placebo. These are small, short measurements, not proof of benefit.
?How is it different from belimumab?
Belimumab is an approved antibody that blocks BAFF. Edratide is a short peptide meant to induce tolerance; in mice it lowered BAFF as one of many downstream effects, but it was never approved.
References
- [other] PubChem CID 16214485, Edratide: formula C111H149N27O28, molecular weight 2309.5. Read October 28, 2026. https://pubchem.ncbi.nlm.nih.gov/compound/16214485
- [registry] ClinicalTrials.gov API v2, read October 28, 2026: NCT00203151 (phase 2, terminated).
- [clinical-trial] Urowitz MB, et al. "Safety and efficacy of hCDR1 (Edratide) in patients with active systemic lupus erythematosus: results of phase II study." Lupus Sci Med, 2015;2(1):e000104. PMID: 26301100.
- [clinical-trial] Sthoeger ZM, et al. "Treatment of lupus patients with a tolerogenic peptide, hCDR1 (Edratide): immunomodulation of gene expression." J Autoimmun, 2009;33(1):77-82. PMID: 19346102.
- [pubmed] Sthoeger Z, et al. "The tolerogenic peptide, hCDR1, down-regulates the expression of interferon-α in murine and human systemic lupus erythematosus." PLoS One, 2013;8(3):e60394. PMID: 23555966.
- [pubmed] Sthoeger Z, et al. "Indoleamine-2,3-dioxygenase in murine and human systemic lupus erythematosus: Down-regulation by the tolerogeneic peptide hCDR1." Clin Immunol, 2018;197:34-39. PMID: 30170030.
- [pubmed] Sthoeger ZM, et al. "The tolerogenic peptide hCDR1 downregulates pathogenic cytokines and apoptosis and upregulates immunosuppressive molecules and regulatory T cells in peripheral blood mononuclear cells of lupus patients." Hum Immunol, 2009;70(3):139-45. PMID: 19280712.
- [pubmed] Sthoeger Z, et al. "The tolerogenic peptide hCDR1 immunomodulates cytokine and regulatory molecule gene expression in blood mononuclear cells of primary Sjogren's syndrome patients." Clin Immunol, 2018;192:85-91. PMID: 29730433.
- [pubmed] Elmann A, et al. "Altered gene expression in mice with lupus treated with edratide, a peptide that ameliorates the disease manifestations." Arthritis Rheum, 2007;56(7):2371-81. PMID: 17599765.
- [review] Mozes E, et al. "A novel tolerogenic peptide, hCDR1, for the specific treatment of systemic lupus erythematosus." Autoimmun Rev, 2010;10(1):22-6. PMID: 20659591.
- [pubmed] Luger D, et al. "A peptide based on the complementarity determining region 1 of a human monoclonal autoantibody ameliorates spontaneous and induced lupus manifestations in correlation with cytokine immunomodulation." J Clin Immunol, 2004;24(6):579-90. PMID: 15622442.
- [pubmed] Mauermann N, et al. "Amelioration of lupus manifestations by a peptide based on the complementarity determining region 1 of an autoantibody in severe combined immunodeficient (SCID) mice engrafted with peripheral blood lymphocytes of systemic lupus erythematosus (SLE) patients." Clin Exp Immunol, 2004;137(3):513-20. PMID: 15320900.
- [pubmed] Sharabi A, et al. "A new model of induced experimental systemic lupus erythematosus (SLE) in pigs and its amelioration by treatment with a tolerogenic peptide." J Clin Immunol, 2010;30(1):34-44. PMID: 19756988.
- [pubmed] Lapter S, et al. "Amelioration of brain pathology and behavioral dysfunction in mice with lupus following treatment with a tolerogenic peptide." Arthritis Rheum, 2009;60(12):3744-54. PMID: 19950283.
- [pubmed] Telerman A, et al. "Induction of hippocampal neurogenesis by a tolerogenic peptide that ameliorates lupus manifestations." J Neuroimmunol, 2011;232(1-2):151-7. PMID: 21129786.
- [pubmed] Parameswaran R, et al. "B-cell activating factor (BAFF) plays a role in the mechanism of action of a tolerogenic peptide that ameliorates lupus." Clin Immunol, 2009;131(2):223-32. PMID: 19188092.
- [pubmed] Lapter S, et al. "A role for the B-cell CD74/macrophage migration inhibitory factor pathway in the immunomodulation of systemic lupus erythematosus by a therapeutic tolerogenic peptide." Immunology, 2011;132(1):87-95. PMID: 20738420.
- [pubmed] Sela U, et al. "A peptide that ameliorates lupus up-regulates the diminished expression of early growth response factors 2 and 3." J Immunol, 2008;180(3):1584-91. PMID: 18209054.
- [review] Sthoeger Z, et al. "Novel approaches to the development of targeted therapeutic agents for systemic lupus erythematosus." J Autoimmun, 2014;54:60-71. PMID: 24958634.
- [review] Amarilyo G, et al. "Preclinical studies with synthetic peptides in systemic lupus erythematosus." Front Biosci (Landmark Ed), 2012;17(5):1940-7. PMID: 22201847.
Sources & Citations
Every study on this page was read from its PubMed record on October 29, 2026. Identity data come from PubChem (CID 16214485); trial status from ClinicalTrials.gov (NCT00203151) and regulatory status from Drugs@FDA (openFDA) and the EMA medicines list. Grey Peptides sells nothing and links to no vendor.
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. Talk to a licensed clinician about your own situation.