arbaclofen

Arbaclofen is an investigational drug undergoing randomized, placebo-controlled clinical trials for potential use in the following conditions:

• To reduce muscle stiffness (spasticity) in patients with multiple sclerosis, an autoimmune neurological disorder
• To improve symptoms of autism spectrum disorder, a condition that causes difficulties with social behavior, interaction, and communication
• To improve social function and behavior in fragile X syndrome, an inherited condition that causes intellectual disability and autism spectrum disorder

Gamma-aminobutyric acid (GABA) is the primary inhibitory chemical messenger (neurotransmitter) in the central nervous system. Impaired functioning of GABA and an imbalance between excitatory and inhibitory neurotransmission are believed to be linked to fragile X syndrome and autism spectrum disorder.

Arbaclofen works by enhancing the activity of GABA. Preliminary study results suggest that arbaclofen may improve social function and behavior in patients with these conditions. By enhancing GABA activity, arbaclofen is believed to inhibit neurotransmission through spinal reflex arcs that mediate reflex muscle contraction and may help reduce muscle spasticity in multiple sclerosis.

Further randomized, controlled studies are required to establish the safety and efficacy of the drug. Currently, arbaclofen is still under investigation, and is not approved by the FDA, nor commercially available in the U.S. market.

Warning

• Arbaclofen is an investigational drug yet to be approved by the FDA. There are no data available on contraindications and warnings pertaining to the drug.

Common side effects of arbaclofen reported in clinical trials for use in the treatment of autism include:

• Upper respiratory infection
• Insomnia
• Irritability
• Hyperactivity
• Aggression
• Anxiety
• Agitation
• Sleep disorder
• Drowsiness (somnolence)
• Mood swings
• Vomiting
• Diarrhea
• Decrease in appetite
• Decrease in weight
• Nasal discharge (rhinorrhea)
• Inflammation of the nose and throat (nasopharyngitis)
• Cough
• Nasal congestion
• High temperature (pyrexia)
• Headache
• Rash

Call your doctor immediately if you experience any of the following symptoms or serious side effects while using this drug:

• Serious heart symptoms include fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness;
• Severe headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady;
• Severe nervous system reaction with very stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, and feeling like you might pass out; or
• Serious eye symptoms include blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.

This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.

• Arbaclofen is not yet approved by the FDA and there is no established dosage of arbaclofen.
• Dosages ranging from 10 mg to 30 mg have been used in clinical trials for use in the treatment of autism spectrum disorder in patients of age 5-21.

Overdose

• Arbaclofen is an investigational drug yet to be approved by the FDA. There is no information available on arbaclofen overdose or on the treatment for overdose.

Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.

• Arbaclofen is an investigational drug yet to be approved by the FDA. There is no information available on drug interactions with arbaclofen.

The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.

It is important to always tell your doctor, pharmacist, or health care provider about all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or healthcare provider if you have any questions about the medication.

• Arbaclofen is an investigational drug yet to be approved by the FDA.
• There is no information available on arbaclofen use during pregnancy and breastfeeding.