Cartalax and ARA 290: Joint and Nerve Research Peptides

Cartalax and ARA 290 are two research peptides studied in joint and nerve biology, but they have very different pedigrees. Cartalax is a three-amino-acid cartilage bioregulator (Ala-Glu-Asp) from the Khavinson laboratory in St Petersburg, supported mainly by cell-culture and animal work. ARA 290, also called cibinetide, is an 11-amino-acid peptide engineered from erythropoietin that completed placebo-controlled phase 2 trials in sarcoidosis-associated small-fibre neuropathy and type 2 diabetes. In the UK both are sold as research chemicals for laboratory use only; neither has an MHRA marketing authorisation.

This guide profiles each compound in turn, sets out what the published research actually reports, compares the strength of evidence, and explains what UK researchers should check before buying either.

What is Cartalax?

Cartalax belongs to the family of ultra-short peptide bioregulators developed by Vladimir Khavinson and the St Petersburg Institute of Bioregulation and Gerontology. The group's working theory is that each tissue contains short peptides that regulate gene expression in its own cells, and that synthetic versions of those sequences can restore tissue-specific gene activity. The cartilage-derived sequence they identified was the tripeptide alanine-glutamate-aspartate, synthesised as Cartalax.

The proposed mechanism is epigenetic: the tripeptide is thought to enter the nucleus and influence transcription of chondrocyte genes. Work from the Khavinson group, summarised in a 2023 review by Linkova, Khavinson and colleagues in the International Journal of Molecular Sciences on peptide regulation of chondrogenic stem-cell differentiation, describes short peptides altering expression of the cartilage matrix genes COL2A1 (type II collagen), ACAN (aggrecan) and the transcription factor SOX9, with involvement of WNT, ERK/p38 and Smad 1/5/8 signalling. Reported effects also include changes in proliferation and ageing markers such as Ki-67, p53 and the sirtuins SIRT1 and SIRT6.

The honest summary is that the Cartalax evidence base is thin and almost entirely from one research network. There are no randomised controlled trials of Cartalax in humans published in Western journals, and the Russian clinical reports that exist are small, open-label and difficult to assess. Cartalax is therefore best understood as an early-stage research compound in cartilage biology, not as an established joint therapy.

What is ARA 290 (cibinetide)?

ARA 290 sits at the other end of the evidence spectrum. It was designed by Michael Brines, Anthony Cerami and colleagues at Araim Pharmaceuticals, who reported in the Proceedings of the National Academy of Sciences (2008) that the tissue-protective effects of erythropoietin (EPO) could be separated from its red-blood-cell-stimulating effects. They isolated an 11-amino-acid sequence from the helix B surface of EPO, which they named ARA 290 and later cibinetide.

The peptide activates what the group termed the innate repair receptor, a heterocomplex of the EPO receptor and the beta-common receptor (CD131) that is expressed at low levels in healthy tissue and up-regulated after injury or inflammation. Activation is reported to dampen local inflammation, inhibit apoptosis and promote repair, without binding the classical homodimeric EPO receptor that drives erythropoiesis. That distinction matters: EPO itself has been studied for neuroprotection but raises haematocrit and clotting risk, which ARA 290 was designed to avoid.

ARA 290 clinical trials in small-fibre neuropathy

ARA 290 is unusual among research peptides in having a run of peer-reviewed human trials, most from a collaboration between Araim and the Leiden University Medical Centre anaesthesiology group led by Albert Dahan.

Sarcoidosis, 2012 to 2013. A randomised, double-blind pilot study by Heij and colleagues in Molecular Medicine (2012) tested ARA 290 in sarcoidosis patients with symptoms of small-fibre neuropathy, a painful condition in which the thin sensory nerve fibres in skin and cornea are lost. A larger follow-up by Dahan and colleagues in the same journal (2013) reported that 28 days of treatment improved neuropathic symptoms, increased corneal nerve fibre density measured by confocal microscopy, altered cutaneous temperature sensitivity and increased exercise capacity on the six-minute walk test compared with placebo.

Type 2 diabetes, 2015. Brines and colleagues in Molecular Medicine (2015) ran a phase 2 double-blind, placebo-controlled trial in patients with type 2 diabetes and neuropathic symptoms. Over a 28-day treatment period and 56-day observation window, the ARA 290 group showed improvements in HbA1c and lipid profile and a significant reduction in neuropathic symptoms on the PainDetect questionnaire.

Phase 2b, 2017. Culver, Dahan and colleagues in Investigative Ophthalmology and Visual Science (2017) reported a 28-day randomised phase 2b trial of cibinetide in 64 patients with sarcoidosis-associated small-fibre loss and neuropathic pain (NCT02039687). The higher of the doses studied produced a significant increase of around 23% in corneal nerve fibre area versus placebo, alongside an increase in regenerating GAP-43-positive fibres in skin biopsies, which the authors interpreted as evidence of a disease-modifying effect on nerve fibre abundance rather than pain relief alone.

The trials were small and short, and cibinetide has not progressed to a marketing authorisation anywhere. But the combination of a defined receptor, placebo-controlled human data and objective structural endpoints puts it in a different category from most peptides sold for research.

Cartalax vs ARA 290: evidence compared

How these peptides are used in laboratory research

Because their proposed mechanisms are so different, the two compounds tend to appear in different kinds of study.

• Cartalax: chondrocyte and mesenchymal stem-cell cultures measuring COL2A1, ACAN and SOX9 expression; cartilage explant models; comparison against other cartilage-directed peptides in chondrogenic differentiation assays.
• Cartalax: attempts to replicate the Khavinson findings with independent methods, which would be the most valuable contribution any new lab could make.
• ARA 290: cell and animal models of nerve injury, ischaemia and inflammation where the innate repair receptor is up-regulated, including studies on islet transplantation and diabetic neuropathy.
• ARA 290: corneal confocal microscopy and skin-biopsy methods, following the endpoints used in the sarcoidosis trials, as a model for measuring small-fibre regeneration.
• Both: analytical and stability work. A tripeptide and an 11-mer are both straightforward to characterise by HPLC and mass spectrometry.

Researchers working on tissue repair more broadly sometimes study these compounds alongside BPC-157 and TB-500, the two peptides in Calibre's Wolverine blend, which have their own body of animal literature in tendon and ligament models.

Are Cartalax and ARA 290 legal in the UK?

Yes. Both Cartalax and ARA 290 are legal to buy, sell and possess in the UK as research chemicals. Neither is a controlled substance under the Misuse of Drugs Act 1971 and neither is covered by the Psychoactive Substances Act 2016. Neither has an MHRA marketing authorisation, so supplying either for human medicinal use, or marketing them with claims about joint pain or neuropathy, is unlawful under the Human Medicines Regulations 2012. UK suppliers sell them strictly for research, and this article reports the literature rather than making claims about any product.

What to check before you buy Cartalax or ARA 290 in the UK

Short peptides are cheap to make and easy to make badly. A tripeptide like Cartalax can be mis-sequenced or under-weighed and still look plausible on a label; ARA 290 is long enough that deletion sequences and incomplete deprotection show up as impurities on a good HPLC trace. In both cases the certificate of analysis is the only meaningful check.

1. Ask for a batch-specific certificate of analysis with HPLC purity and mass-spectrometry identity. Calibre pens are tested by Janoshik Analytical and COAs are published on the site's COA page.
2. Confirm the stated quantity is peptide content. Calibre's Cartalax pen is 20mg and the ARA 290 pen is 32mg.
3. Look for a purity target above 99% and check the retention time and mass on the COA correspond to the correct sequence.
4. Store refrigerated and protected from light; record the batch number in your lab notebook so results can be traced to a specific COA.
5. Prefer pre-filled, precision-made pens if your workflow benefits from consistent volumes rather than reconstituting lyophilised powder.

Summary

Cartalax and ARA 290 are grouped together as joint and nerve research peptides, but their evidence could hardly be more different. Cartalax is a Khavinson bioregulator with an intriguing mechanism and almost no independent confirmation. ARA 290 is a rationally designed EPO derivative with a named receptor and placebo-controlled phase 2 data showing measurable small-fibre regeneration. Both are legal for UK researchers to buy as research chemicals, both lack any MHRA licence, and for both the certificate of analysis is where due diligence starts.