In November 2017 the Company has contracted with City of Hope's Center for Biomedicine and Genetics ("COH") to produce clinical supplies of NurOwn® adult stem cells for the Company’s ongoing Phase 3 clinical study. The Company has paid COH $2,665 as advance payment which was recorded as prepaid expense and is amortized over the term of the agreement. As of September 30, 2018, $1,103 and $551 were recorded as current and long-term prepaid expenses, respectively, compared to $1,103 and $1,378 that were recorded as current and long-term prepaid expense, respectively, as of December 31, 2017.