FDA Approves Pyros' Infantile Spasm Treatment

The U.S. Food and Drug Administration (FDA) has approved a new ready-to-use oral solution of vigabatrin, developed by Pryos Pharmaceuticals, for the treatment of infantile spasms. This approval marks the first new drug formulation in this therapeutic area in 15 years.

Pryos Pharmaceuticals, based in the United States, has introduced Vigafyde, an oral solution of vigabatrin intended for pediatric patients aged one month to two years, particularly where the benefits of the treatment outweigh the risks of potential vision loss. The approval was announced on June 17.

Infantile spasms, a rare and severe form of epilepsy, have been historically treated in the U.S. with Sabril (vigabatrin) from Lundbeck Pharmaceuticals and its generic equivalents. Sabril was initially approved by the FDA in 2009, after Lundbeck acquired the U.S. commercialization rights from Sanofi. Sabril is available in 500mg tablets and powder form for oral solutions.

Given the risk of permanent vision loss associated with vigabatrin, the FDA requires a Risk Evaluation and Mitigation Strategy (REMS) for its use. Patients prescribed Vigafyde must be enrolled in the Vigabatrin REMS program. Pryos plans to launch Vigafyde with this REMS program in the second half of 2024. The company also offers a support team to assist families throughout the treatment process.

Vigafyde will be added to Pyros Pharmaceuticals' portfolio alongside Vigpoder, another oral solution of vigabatrin that is therapeutically equivalent to Sabril. Vigpoder received FDA approval in 2022.

Infantile spasms typically manifest in children under one year of age and can result in long-term neurological issues, including persistent seizures, other forms of epilepsy, and autism spectrum disorder. Vigafyde functions by inhibiting GABA transaminase, leading to increased levels of GABA in the brain. This helps to modulate neuronal excitability and provides better seizure control.

Sabril experienced significant sales in the U.S., peaking at $229 million in 2017. However, following the expiration of several market exclusivities, its sales have significantly declined. It is projected to generate approximately $12 million annually by 2030, according to data from GlobalData’s Pharma Intelligence Centre.

Edwin Urrutia, the Chief Operating Officer of Pryos Pharmaceuticals, expressed that the approval of Vigafyde marks a significant milestone for patients and caregivers who have been waiting for a ready-to-use formulation of vigabatrin.

In addition to Vigafyde, Pryos Pharmaceuticals is developing two other drugs, PYR-001 and PYR-002, which have undisclosed therapeutic targets. PYR-001 is currently in late-stage clinical trials, while PYR-002 remains in the early stages of development.