OP50 – 3017: The International Collaborative Infantile Spasms Study (ICISS) comparing hormonal therapies (prednisolone or tetracosactide depot) and vigabatrin versus hormonal therapies alone in the treatment of infantile spasms: Early clinical outcome

Abstract

Objective To compare hormonal therapies (Prednisolone or tetracosactide depot) and vigabatrin versus hormonal therapies alone in the treatment of infantile spasms. Methods Between March 2007 and May 2014, infants with IS and a compatible EEG were enrolled in a multicenter treatment trial. Infants were randomized to receive either hormonal therapy and vigabatrin or hormonal therapy alone. A second stage randomization allowed hormonal treatment to be allocated as either prednisolone or tetracosactide depot. Minimum doses were: vigabatrin 100 mg/kg/day, prednisolone 40 mg per day, or IM tetracosactide depot 0.5 mg on alternate days. The early primary outcome measure was cessation of spasms on and between days 14 and 42. Analysis is by intention to treat. Results 377 children were enrolled and early clinical outcome data will be available on 376 (1 case withdrew). 185 were allocated hormonal therapy and vigabatrin and 191 were allocated hormonal therapy alone. 133/185 (71.9%) on combination therapy versus 108/191 (56.6%) on hormonal therapy alone achieved a primary clinical response: treatment difference 15.3% (95% CI 5.4% to 25.2%, p=0.002). The treatment effect favouring combination therapy remained highly significant in a logistic regression analysis controlling for underlying aetiology, country of enrollment, whether hormonal therapy was randomized or not, and gender (Odds ratio 2.03, 95% CI 1.3 to 3.2, p=0.002). Treatment response was also significantly faster on combination therapy (median response time = 2 days, IQR 2–4 days) than hormonal therapy alone (median response time = 4 days, IQR 3–6 days, p Conclusion The ICISS trial shows that combination therapy of hormonal therapy + vigabatrin is associated with a more rapid clinical response and greater proportion of infants achieving spasm cessation than on hormonal therapy alone.