Last reviewed · How we verify

Mecobalamin IM injection

Eisai Co., Ltd. · FDA-approved active Small molecule ✓ Verified May 2026

Mecobalamin IM injection is a Vitamin B12 analog Small molecule drug developed by Eisai Co., Ltd.. It is currently FDA-approved for Vitamin B12 deficiency with neurological manifestations, Peripheral neuropathy associated with B12 deficiency, Subacute combined degeneration.

Mecobalamin is an active form of vitamin B12 that replenishes cellular cobalamin stores and restores normal methylation and energy metabolism.

Mecobalamin is a small molecule administered via intramuscular (IM) injection, used to treat conditions such as Diabetic Peripheral Neuropathy and Peripheral Neuropathy, as well as Amyotrophic Lateral Sclerosis (ALS).

At a glance

Generic nameMecobalamin IM injection
SponsorEisai Co., Ltd.
Drug classVitamin B12 analog
TargetMethionine synthase; B12-dependent enzymes
ModalitySmall molecule
Therapeutic areaNeurology; Hematology
PhaseFDA-approved

Mechanism of action

Mecobalamin is a methylcobalamin derivative that acts as a cofactor for methionine synthase and other B12-dependent enzymes essential for DNA synthesis, myelin formation, and neuronal function. It crosses the blood-brain barrier more effectively than cyanocobalamin and is directly utilized in cellular metabolism without requiring enzymatic conversion. This makes it particularly effective for treating B12 deficiency-related neurological conditions.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

Frequently asked questions about Mecobalamin IM injection

What is Mecobalamin IM injection?

Mecobalamin IM injection is a Vitamin B12 analog drug developed by Eisai Co., Ltd., indicated for Vitamin B12 deficiency with neurological manifestations, Peripheral neuropathy associated with B12 deficiency, Subacute combined degeneration.

How does Mecobalamin IM injection work?

Mecobalamin is an active form of vitamin B12 that replenishes cellular cobalamin stores and restores normal methylation and energy metabolism.

What is Mecobalamin IM injection used for?

Mecobalamin IM injection is indicated for Vitamin B12 deficiency with neurological manifestations, Peripheral neuropathy associated with B12 deficiency, Subacute combined degeneration, Pernicious anemia with neurological complications.

Who makes Mecobalamin IM injection?

Mecobalamin IM injection is developed and marketed by Eisai Co., Ltd. (see full Eisai Co., Ltd. pipeline at /company/eisai).

What drug class is Mecobalamin IM injection in?

Mecobalamin IM injection belongs to the Vitamin B12 analog class. See all Vitamin B12 analog drugs at /class/vitamin-b12-analog.

What development phase is Mecobalamin IM injection in?

Mecobalamin IM injection is FDA-approved (marketed).

What are the side effects of Mecobalamin IM injection?

Common side effects of Mecobalamin IM injection include Injection site reactions, Headache, Dizziness, Itching or rash, Hypokalemia (rare).

What does Mecobalamin IM injection target?

Mecobalamin IM injection targets Methionine synthase; B12-dependent enzymes and is a Vitamin B12 analog.

Related

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing