Pyros Pharmaceuticals Announces FDA Approval of VIGAFYDE™ (vigabatrin) as the First and Only Ready-to-Use Vigabatrin Oral Solution

PARSIPPANY, N.J.--()--Pyros Pharmaceuticals, Inc. (Pyros or the Company), a leader in the development of enhanced specialty pharmaceuticals for rare diseases, announced today that the U.S. Food and Drug Administration (FDA) has approved VIGAFYDE™, the only ready-to-use vigabatrin oral solution. VIGAFYDE™ (vigabatrin) oral solution, is indicated as a monotherapy for the treatment of pediatric patients 1 month to 2 years of age with infantile spasms (IS), where the potential benefits outweigh the potential risk of vision loss. Please see full Prescribing Information below to view Important Safety Information, including BOXED WARNINGS.

Infantile spasms, a rare but severe form of epilepsy, poses significant challenges for patients and their families. Pyros is committed to providing dependable services and an affordable treatment option to help ensure that families facing an IS diagnosis, and whose children are prescribed vigabatrin can quickly obtain this essential therapy.

"The approval of VIGAFYDE™ marks the first new drug indicated for infantile spasms in fifteen years and underscores our unwavering commitment to supporting families facing this challenging condition," stated Michael Smith, co-founder and Chief Executive Officer of Pyros.

“This is a momentous day for patients and caregivers who have long awaited the first ready-to-use vigabatrin. I believe this approval will bring renewed energy and momentum to the infantile spasms community, enhancing our efforts to improve disease education, develop care pathways, and expand investment in infantile spasms research,” stated Edwin Urrutia, co-founder and Chief Operating Officer at Pyros.

VIGAFYDE™ is expected to be available in the second half of 2024. Additionally, Pyros Total Care™, the Company’s personalized comprehensive support program, is available to assist families throughout the treatment journey.

About Pyros Total Care

As part of the Company’s commitment to prioritizing patient access to treatments for those who need them most, Pyros provides ongoing personalized support to caregivers through Pyros Total Care™ for those prescribed VIGAFYDE™. The support program offers personal assistance and financial resources to caregivers whose child is starting or continuing therapy.

Our dedicated support team includes a nurse educator, reimbursement support, and a clinical pharmacist. For more information, visit or call 1-888-760-8330, Monday to Friday, 8 a.m. to 5 p.m. Central Time.

About Infantile Spasms

Infantile spasms (IS) is a rare, severe form of epilepsy that typically begins in children less than one year old.1 Infantile spasms can appear as subtle but repetitive movements that can often be overlooked or misdiagnosed. IS can lead to long-term permanent issues such as continued seizures, other forms of epilepsy, autism spectrum disorder, and developmental issues.2 The American Academy of Neurology conducted a systematic review of treatment for IS and concluded that successful treatment of IS can improve the long-term prognosis.3

About Vigabatrin

Vigabatrin is a medication used in the treatment of infantile spasms and is designed to inhibit the enzyme GABA transaminase, consequently increasing gamma-aminobutyric acid (GABA) levels in the brain.4,5 This release is thought to enhance seizure control for patients by modulating neuronal excitability.6 Vigabatrin's mechanism of action underscores its importance in treating seizure disorders.7 Its impact may extend beyond seizure management, with emerging research indicating potential benefits in mitigating neurodevelopmental complications associated with certain epilepsy syndromes.8

Vigabatrin REMS

The U.S. FDA has approved a single shared system Risk Evaluation and Mitigation Strategy (REMS) for all vigabatrin products called the Vigabatrin REMS. This strategy is mandated by the FDA to ensure that patients and healthcare providers make informed risk-benefit decisions before starting treatment, and to ensure the proper use of vigabatrin throughout the treatment process.

Healthcare providers must be certified in the Vigabatrin REMS to prescribe VIGAFYDE™, and patients must be enrolled in the Vigabatrin REMS to receive VIGAFYDE™. Once certified and enrolled, prescribers and patients remain in the Vigabatrin REMS and do not need to undergo recertification or re-enrollment.


VIGAFYDE™ (vigabatrin) is indicated as monotherapy for the treatment of infantile spasms in pediatric patients 1 month to 2 years of age for whom the potential benefits outweigh the potential risk of vision loss.



See full Prescribing Information for complete BOXED WARNING.


  • VIGAFYDE can cause permanent bilateral concentric visual field constriction, including tunnel vision that can result in disability. In some cases, VIGAFYDE may also decrease visual acuity.
  • Risk increases with increasing dose and cumulative exposure, but there is no dose exposure to VIGAFYDE known to be free of risk of vision loss.
  • Risk of new and worsening vision loss continues as long as VIGAFYDE is used, and possibly after discontinuing VIGAFYDE.
  • Baseline and period vision assessment is recommended for patients on VIGAFYDE. However, this assessment cannot always prevent vision damage.
  • VIGAFYDE is available only through a restricted program called the Vigabatrin REMS.


  • VIGAFYDE can cause permanent vision loss. Because of this risk and because VIGAFYDE, when it is effective, provides an observable symptomatic benefit; patient response and continued need for treatment should be periodically assessed.
  • Monitoring of vision by an ophthalmic professional with expertise in visual field interpretation and the ability to perform dilated indirect ophthalmoscopy of the retina is recommended. Because vision testing in infants and children is difficult, vision loss may not be detected until it is severe. VIGAFYDE is not approved for use in pediatric patients older than 2 years of age or in adults.
  • Due to the risk of permanent vision loss, VIGAFYDE is only available through the Vigabatrin REMS. Further information is available at or 1-866-244-8175.
  • Abnormal Magnetic Resonance Imaging (MRI) signal changes and Intramyelinic Edema (IME) in some infants and young children treated with vigabatrin have been observed. These changes generally resolved with discontinuation of treatment and resolved in a few patients despite continued use.
  • VIGAFYDE should be withdrawn gradually to avoid withdrawal seizures. Patients and caregivers should be told not to suddenly discontinue VIGAFYDE therapy.
  • Monitor for symptoms of anemia.
  • VIGAFYDE causes somnolence and fatigue.
  • In pediatric clinical trials (pooled data), the incidence of peripheral neuropathy and edema observed in pediatric patients was similar on vigabatrin and placebo.
  • VIGAFYDE causes weight gain in pediatric patients.


Most common (≥10%) adverse reactions in patient receiving low-dose (18-36 mg/kg/day) vs high-dose (100-148 mg/kg/day) vigabatrin, respectively, were upper respiratory tract infection (51%, 46%), otitis media (44%, 30%), fever (29%, 19%), viral infection (20%, 19%), sedation (19%, 17%), somnolence (17%, 19%), irritability (16%, 23%), constipation (14%, 12%), vomiting (14%, 20%), diarrhea (13%, 12%), nasal congestion (13%, 4%), pneumonia (13%, 11%), insomnia (10%, 12%), ear infection (7%, 14%), and rash (8%, 11%).

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit or call 1-800-FDA-1088 or Pyros at 1-855-406-1010.

Please see full Prescribing Information, including BOXED WARNING, for additional Important Safety Information.

About Pyros

Pyros Pharmaceuticals is developing enhanced specialty pharmaceuticals for rare diseases. Our mission is to elevate the standard of care for infantile spasms, providing treatment options that significantly improve the lives of affected children. Through our enhanced therapies and comprehensive support services, we aim to assist providers and caregivers in navigating the complexities of the patient journey.

For more information, please visit:

Forward-Looking Statements

The Company has made statements throughout this press release which constitute forward-looking statements. These statements involve known and unknown risks, uncertainties and other factors that may cause its actual results, levels of activity, performance or achievements to be materially different from any results, levels of activity, performance or achievements expressed or implied by any such forward-looking statements. In some cases you can identify forward-looking statements by terminology such as “may,” “will,” “should,” “could,” “expect,” “hopes,” “intends,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “likely,” “potential,” or “continue” or the negative of these terms and similar words. Although management believe that the expectations reflected in these forward-looking statements are reasonable, management cannot guarantee future results, levels of activity, performance or achievements. Furthermore, management undertakes no obligation to update any forward-looking statements for any reason unless required to do so by law.


  1. Mackay, M. T., Weiss, S. K., Adams-Webber, T., et al. (2004). Practice parameter: medical treatment of infantile spasms. Report of the American Academy of Neurology and the Child Neurology Society. Neurology, 62(10), 1668-1681.
  2. Lux, A. L., & Osborne, J. P. (2004). A proposal for case definitions and outcome measures in studies of infantile spasms and West syndrome: consensus statement of the West Delphi group. Epilepsia, 45(11), 1416-1428.
  3. Pellock, J. M., Hrachovy, R., Shinnar, S., et al. (2010). Infantile spasms: a U.S. consensus report. Epilepsia, 51(10), 2175-2189.
  4. Cilio, M. R., & Cross, H. J. (2011). Vigabatrin. Neurotherapeutics, 8(2), 330–337.
  5. Löscher, W., & Schmidt, D. (2004). New horizons in the development of antiepileptic drugs: innovative strategies. Epilepsy Research, 60(2–3), 77–159.
  6. Houston, S. M., & Smart, T. G. (2006). GABA pharmacology: the search for analgesics. Current Opinion in Investigational Drugs, 7(1), 48–55.
  7. Wheless, J. W. (2004). Vigabatrin: efficacy and safety in pediatric epilepsy. Journal of Child Neurology, 19(Suppl 1), S21–S29.
  8. Chiron, C. (2006). Vigabatrin in the treatment of epilepsy: literature review. Epileptic Disorders, 8(S1), S33–S38.



Edwin Urrutia
Chief Operating Officer


Edwin Urrutia
Chief Operating Officer