diff --git a/AUTHORS.md b/AUTHORS.md
index 1906975..baa4721 100644
--- a/AUTHORS.md
+++ b/AUTHORS.md
@@ -1,6 +1,7 @@
 Redis Session Store authors
 ===========================
 
+- Atsushi Tatsuma
 - Ben Marini
 - Bill Ruddock
 - Dan Buch
diff --git a/lib/redis-session-store.rb b/lib/redis-session-store.rb
index 9e3514a..66a6157 100644
--- a/lib/redis-session-store.rb
+++ b/lib/redis-session-store.rb
@@ -42,7 +42,7 @@ def initialize(app, options = {})
 
     @default_options[:namespace] = 'rack:session'
     @default_options.merge!(options[:redis] || {})
-    init_options = options[:redis]&.reject { |k, _v| %i[expire_after key_prefix].include?(k) } || {}
+    init_options = options[:redis]&.reject { |k, _v| %i[expire_after ttl key_prefix].include?(k) } || {}
     @redis = init_options[:client] || Redis.new(init_options)
     @on_redis_down = options[:on_redis_down]
     @serializer = determine_serializer(options[:serializer])