The United Kingdom Infantile Spasms Study comparing vigabatrin with prednisolone or tetracosactide at 14 days: a multicentre, randomised controlled trial

BACKGROUND: Infantile spasms, which comprise a severe infantile seizure disorder, have a high morbidity and are difficult to treat. Hormonal treatments (adrenocorticotropic hormone and prednisolone) have been the main therapy for decades, although little evidence supports their use. Vigabatrin has been recorded to have a beneficial effect in this disorder. We aimed to compare the effects of vigabatrin with those of prednisolone and tetracosactide in the treatment of infantile spasms.

METHODS: The United Kingdom Infantile Spasms Study assessed these treatments in a multicentre, randomised controlled trial in 150 hospitals in the UK. The primary outcome was cessation of spasms on days 13 and 14. Minimum doses were vigabatrin 100 mg/kg per day, oral prednisolone 40 mg per day, or intramuscular tetracosactide depot 0.5 mg (40 IU) on alternate days. Analysis was by intention to treat.

FINDINGS: Of 208 infants screened and assessed, 107 were randomly assigned to vigabatrin (n=52) or hormonal treatments (prednisolone n=30, tetracosactide n=25). None was lost to follow-up. Proportions with no spasms on days 13 and 14 were: 40 (73%) of 55 infants assigned hormonal treatments (prednisolone 21/30 [70%], tetracosactide 19/25 [76%]) and 28 (54%) of 52 infants assigned vigabatrin (difference 19%, 95% CI 1%-36%, p=0.043). Two infants allocated tetracosactide and one allocated vigabatrin received prednisolone. Adverse events were reported in 30 (55%) of 55 infants on hormonal treatments and 28 (54%) of 52 infants on vigabatrin. No deaths were recorded.

INTERPRETATION: Cessation of spasms was more likely in infants given hormonal treatments than those given vigabatrin. Adverse events were common with both treatments.