13. Commitments and Contingencies In August 2010, the Company entered into a five-year, non-cancelable operating lease for office and laboratory space. The Company has the option to extend the lease for one additional term of two years. The lease commenced on January 1, 2011, with the Company providing a security deposit of $400,000. In accordance with the operating lease agreement, the Company reduced its security deposit by $80,000 to $320,000 on January 14, 2013. In May, 2013, the Company entered into a six month operating lease for laboratory space with an option to extend the lease an additional six months. In September 2013, the Company exercised the extension. In June 2014, the Company further extended the lease on a month-to-month basis, cancelable with not less than 60 days notice. I n May, 2013, the Company entered into a two-year operating lease for additional office, laboratory and manufacturing space. The lease includes two one-year extension options. The first one-year extension option was exercised in 2014. In July, 2014, the Company entered into a lease amendment to expand facilities at the Company s headquarters in Lexington, MA. The term of the lease amendment ends concurrently with the original lease entered into in August 2010 and will increase the monthly base rent by approximately $39,000 per month through December 2015. The Company retains the option to extend the lease for one additional term of two years. In November, 2014 the Company entered into an agreement to rent additional office space in Lexington, MA. The term of the agreement is two years, commencing December 2014. In connection with this agreement, the Company paid a security deposit totaling $50,000, which is recorded as a component of other assets in the consolidated balance sheets. In November, 2014, the Company entered into a lease for additional laboratory space in Lexington, MA. The Company is expected to occupy the space on April 1, 2015, once the build-out of the space is complete, and the lease term extends for six year