The 21-year-old, who joined the Cottagers from Palermo in 2011, has featured in both of their league matches this season.
"Of course the Sunderland and Arsenal results were completely different. But personally I'm happy with my development and how I'm doing," he told the club's official website.
"I'm just continuing to work hard and I'm always looking forward to the next game."
Kasami is also expected to feature when his side face Burton Albion in the second round of the League Cup on Tuesday.