Abstract A041: Recurrent Symptomatic Hemorrhage after Discontinuation of Atorvastatin versus Placebo in Randomized Trial of Hemorrhagic Cerebral Cavernous Malformations

Background: There is much interest in drug development to prevent rebleeding after symptomatic hemorrhage (SH) in cerebral cavernous malformations (CCM) and its neurologic sequelae. A recent randomized prospective controlled trial (AT CASH EPOC clinicaltrials.gov NCT02603328) demonstrated that atorvastatin for up to 2 years was safe but did not significantly alter CCM iron deposition or SH rates. However, the consequences of discontinuing atorvastatin in CCM patients remain unknown. Given reports of rebound effects with discontinuation of statins, we here hypothesize that SH recurs more frequently in hemorrhagic CCMs after discontinuation of atorvastatin than placebo. Methods: We conducted 12-month (±1 month) post-treatment follow-up of all 80 patients randomized in the AT CASH EPOC trial (41 atorvastatin, 39 placebo) to identify potential recurrent SH from the date of trial drug discontinuation. Every SH was adjudicated by review of imaging and corresponding symptoms. Patients were excluded for < 90% compliance with study drug or its discontinuation <3 months during the trial, and for lack of follow-up. Cases were censored during follow-up upon CCM resection/radiation or atorvastatin initiation/re-initiation. Results: Follow-up included 33 patients who had been randomized to placebo and 32 who had taken atorvastatin.During follow-up, 4 SH events occurred at 3, 49, 84, and 225 days after atorvastatin discontinuation, and only 1 SH 395 days after discontinuing placebo. Kaplan–Meier curves demonstrated significantly lower symptomatic hemorrhage-free survival in the atorvastatin-discontinuation group (log-rank chi=4.136, p=0.042). The Gehan–Breslow–Wilcoxon test (chi=4.080, p=0.043) highlighted early divergence in recurrent SH risk. The hazard ratio was 0.162 (95% CI 0.027–0.977) for placebo vs. atorvastatin discontinuation. Conclusion: While there was no difference in SH rates during 2 years of treatment with atorvastatin versus placebo in randomized clinical trial, discontinuation of atorvastatin was associated with a significantly higher and earlier risk of recurrent SH compared with placebo discontinuation. This raises concern for a rebound effect during the year after statin withdrawal in hemorrhagic CCM patients, potentially mediated by reactivation of Rho-associated kinase. Additional studies are warranted to confirm these observations and to assess whether statin tapering or maintenance therapy can mitigate the risk of discontinuation in hemorrhagic CCM.