ARA 290

What it is

ARA 290, also called cibinetide, is a short peptide designed from part of the erythropoietin (EPO) molecule. EPO is best known for boosting red blood cell production. ARA 290 was engineered to keep some of EPO's tissue-protective signalling while not stimulating red blood cell production.

It has been studied in small human trials for small fibre neuropathy and nerve pain, notably in people with sarcoidosis and type 2 diabetes. It is not a licensed medicine anywhere, so anything sold in vials is a research chemical.

History

The idea emerged from work in the 2000s by Michael Brines, Anthony Cerami and colleagues showing that EPO protects tissues through a different receptor complex than the one that makes red blood cells. ARA 290 was designed to activate only the protective pathway. Small Phase 2 trials were run in the 2010s, with the drug owned by Araim Pharmaceuticals. It has not reached approval.

How it works

ARA 290 is thought to bind a receptor complex called the innate repair receptor (made of the EPO receptor and a second subunit called CD131) found on injured and inflamed tissue. Activating it appears to dampen inflammation and support nerve fibre survival, without the blood-thickening effects of EPO.

Dosage

• In published small human trials, the dose was about 4 mg given as a subcutaneous injection once daily for 28 days. That is a trial regimen, not a recommendation, and results were modest and from small groups.
• Community protocols vary, with some using lower daily doses and some using longer courses. These are extrapolations.

How it is taken

• Subcutaneous injection into belly fat with a 29-31G insulin syringe. Rotate sites.
• Some people split the dose, but the trial protocol was a single daily injection.

How to reconstitute

• For a 10 mg vial, adding 2 ml of bacteriostatic water gives 5 mg/ml. On a 1 ml (100-unit) insulin syringe, 20 units (0.2 ml) is 1 mg, 40 units is 2 mg and 80 units is 4 mg.
• Because the trial-scale dose is high for a peptide, a 10 mg vial gives only a couple of full trial-size doses.
• Add water slowly down the vial wall, swirl gently and do not shake.

How it should arrive

A sealed glass vial with a white to off-white lyophilised cake and an intact crimped cap.

How it should look once reconstituted

A clear, colourless solution. Cloudiness or floating particles mean the vial should not be used.

What to expect, and when

• In the small trials, nerve-pain and nerve fibre measures changed over the 28-day dosing period and a few weeks after.
• Neuropathy changes are slow in general, so judge it over weeks to a couple of months rather than days.

Side effects

• Generally well tolerated in the small trials.
• Injection-site reactions such as redness or irritation.
• Headache and mild tiredness reported occasionally.

Risks

• Trial sample sizes were small, so rarer side effects could be missed.
• Long-term safety is not known.
• It is derived from EPO, a pathway that has links to tumour growth and clotting in some contexts. ARA 290 does not act on the red blood cell receptor, but anyone with a cancer history should talk to a doctor before use.
• Neuropathy needs a proper diagnosis. Nerve symptoms can come from vitamin deficiency, diabetes, thyroid problems and more, and those should be sorted first.
• Quality varies on the grey market.

Potential gains

• In small human trials, improvements in small nerve fibre density and neuropathic symptoms in sarcoidosis. Results in diabetic neuropathy were more mixed.
• Reduced inflammation markers in some studies.
• In animals, protection for a range of tissues including nerve, heart and kidney.
• No evidence yet that it works for non-neuropathy goals like general recovery.

Other useful information

This is one of the better-supported research peptides in terms of having real, peer-reviewed human trials, but those trials were small and the programme has not led to an approved drug. If you have nerve pain, see a GP or neurologist first. Treatable causes are common.