In short
Hydroxocobalamin acetate is a form of vitamin B12 used as an authorised medicine in the United Kingdom. It is given as an injection to treat vitamin B12 deficiency. The clinical trial data in this page concerns a different substance, thiamine (vitamin B1), which is being studied for brain protection in people with alcohol use disorder. One Phase 2 trial with 60 participants is authorised.
Key points
- Hydroxocobalamin acetate is a vitamin B12 form authorised in the UK for treating vitamin B12 deficiency.
- The registered clinical trial investigates thiamine (vitamin B1), not hydroxocobalamin acetate.
- The trial is Phase 2 and has 60 participants.
- The study is randomised and open-label, taking place in outpatients with alcohol use disorder.
- The primary outcome measures plasma neurofilament light (NFL) levels after 14 days of treatment.
- The trial status is Authorised.
What is hydroxocobalamin acetate?
Hydroxocobalamin acetate is a form of vitamin B12. In the United Kingdom National Health Service formularies, it is listed as an authorised medicine for the treatment of vitamin B12 deficiency. The Buckinghamshire Formulary names hydroxocobalamin 1 mg/1 mL injection as the first-line option for medically diagnosed vitamin B12 deficiency, in line with NICE guidance. It is also known by the trade name Cyanokit when used as a cyanide antidote in emergency poisoning treatment.
How does hydroxocobalamin acetate work?
Hydroxocobalamin is a form of vitamin B12 that the body can use for essential functions including red blood cell formation and nerve function. In the context of cyanide poisoning, hydroxocobalamin acts as a cyanide antidote by binding to cyanide ions, allowing them to be removed from the body. The formulary sources list hydroxocobalamin among the specific drugs used for cyanide poisoning.
Which conditions is it used or studied for?
- Vitamin B12 deficiency — hydroxocobalamin acetate injection is the first-line treatment for medically diagnosed vitamin B12 deficiency in UK formulary guidance.
- Cyanide poisoning — hydroxocobalamin (Cyanokit) is listed as a cyanide antidote in emergency poisoning formularies.
- Alcohol use disorder — the registered clinical trial investigates thiamine (vitamin B1), not hydroxocobalamin acetate, for reducing brain injury in chronic alcohol users.
How is hydroxocobalamin acetate given?
Hydroxocobalamin acetate is given as an injection. The Buckinghamshire Formulary lists hydroxocobalamin 1 mg/1 mL for intramuscular injection. The Suffolk and North East Essex formulary also lists hydroxocobalamin (vitamin B12) as an injection. In the emergency treatment of cyanide poisoning, hydroxocobalamin is available as the Cyanokit formulation.
What do the clinical trials show?
One clinical trial is registered. It is a Phase 2 randomised open-label pilot study called STRENA, which is authorised to begin. The trial investigates thiamine (vitamin B1) at a dose of 1000 mg given orally in outpatients with alcohol use disorder. It is important to note that this trial does not study hydroxocobalamin acetate; the trial record concerns thiamine supplementation.
The primary endpoint is the change in plasma light neurofilaments (NFL) between day 0 and after 14 days of treatment, comparing the thiamine group with a control group without supplementation. The analysis uses intention-to-treat (ITT) and is adjusted for sex and age.
What side effects are known?
The formulary sources do not provide a side effect profile for hydroxocobalamin acetate. One source notes an MHRA alert advising patients with known cobalt allergy to be vigilant for sensitivity reactions when receiving vitamin B12 preparations including hydroxocobalamin.