The Vigabatrin REMS program

Short answer: the Vigabatrin REMS is an FDA-required safety program built around the risk of permanent vision loss. Vigabatrin is available only through it: the prescriber must be certified, the patient must be enrolled, and the medicine can only be dispensed by a certified pharmacy.¹ Contact details from the labels are www.vigabatrinREMS.com and 1-866-244-8175.^1,2

REMS stands for Risk Evaluation and Mitigation Strategy. The requirements on this page are summarized from the FDA labels for vigabatrin, not from the program's own website, which may have more detail on forms and steps.²

Why vigabatrin has a REMS

Vigabatrin can cause permanent narrowing of side vision in both eyes, and it can also reduce sharpness of vision. The risk rises with dose and with time on the medicine, and no dose is known to be free of risk.¹ Based on adult studies, 30% or more of patients can be affected.³ The labels describe vigabatrin as a treatment for people in whom the possible benefits outweigh this risk, and the REMS adds controls on who can prescribe and dispense it, alongside a schedule of vision checks.¹ See vision loss for the full picture.

The REMS applies to every form. The ready-to-use liquid, the powder sachets and the tablets contain the same medicine and carry the same warning.^1,3

The three requirements

The labels list three parts:¹

In practice, this means a prescription for vigabatrin cannot simply be filled at any pharmacy. The medicine comes from a pharmacy that is part of the program. Ask the prescriber's office which pharmacy they use and who to call about refills.

The vision-check schedule

The labels set a schedule of vision assessments:¹

• no later than 4 weeks after starting vigabatrin
• at least every 3 months while on it
• about 3 to 6 months after stopping

The REMS was designed around this baseline exam plus ongoing monitoring.⁴ For babies, standard field tests are not possible, so eye specialists may use other tests such as an electroretinogram, which measures how the retina responds to light.⁴ The vision loss page explains these tests.

Keep a note of each eye appointment. If a check is missed, tell the prescriber.

What the REMS means for families

Researchers interviewed patients and caregivers about REMS programs like this one. The group included 10 people taking vigabatrin and 4 vigabatrin caregivers. People said the programs reassured them, but they also described real burdens, such as having to travel to reach a certified prescriber or pharmacy, and educational materials that were hard to understand.⁵

A companion study interviewed 31 physicians, 6 of whom prescribed vigabatrin. They understood the REMS but felt it changed their practice only a little, and they raised concerns about paperwork and administrative load.⁶

Practical steps that may help:

• Ask the prescriber's team to explain the enrollment forms in plain words. You can ask for a copy of what you sign.
• Ask for the certified pharmacy's phone number and the usual delivery time, so refills do not run late.
• Put every vision check in your calendar as soon as it is booked.
• If you change prescriber, pharmacy or insurance, check that the new one is part of the program before your supply runs low. Only certified prescribers and pharmacies can take part.¹
• Bring questions about the vision risk to each visit.

Starting, switching and stopping

Starting. For infantile spasms, the label advises stopping vigabatrin if it has not clearly helped within 2 to 4 weeks. For refractory complex partial seizures, the limit is 3 months.³ Because the vision risk rises with time on the medicine, this limits exposure when it is not working.¹

Switching forms. Moving between powder and the ready-to-use liquid changes the volume of each dose, because the liquid is twice as concentrated. The label warns prescribers, pharmacists and caregivers to confirm the new volume.¹ See dosage.

Stopping. Vigabatrin should not be stopped suddenly, because that can bring on seizures. The dose is lowered gradually, and a final vision check is due about 3 to 6 months after the last dose.¹