5.	Property, Plant and Equipment, net:

Property, plant and equipment, net at December 31, 2018 and 2017 consist of the following:


	December 31, 2018			December 31, 2017
Leasehold Improvements	$	11,538,377		$	10,873,895
Capitalized Leasehold Interest		7,150,611			—
Manufacturing Equipment		3,779,950			2,477,637
Laboratory Equipment		1,485,544			993,409
Computer and Office Equipment		334,525			276,100
Asset Retirement Obligation		113,678			153,133
Furniture & Fixtures		88,660			93,786

		24,491,345			14,867,960
Less: Accumulated depreciation		(2,477,108	)		(612,231	)

	$	22,014,237		$	14,255,729

In February 2016, the Company sublet a manufacturing facility for a term of 5 years, that included an additional 5-year option. This sub-lease was accounted for as an operating lease. On December 14, 2018, the Company executed a new sub-lease for this manufacturing facility whereby the sub landlords remaining term of 108 years was assigned to the Company. Under the new sub-lease, the Company paid a one-time fee of £5,250,000 (approximately $6,615,000 assuming a rate of $1.26 per GBP on the date of the acquisition) for the assignment and will no longer pay any base rent for the remaining 108 years. The one-time fee and related transaction costs, in the aggregate amount of £5,613,165 (approximately $7,150,611 using a rate of $1.2739 per GBP at December 31, 2018), have been accounted for as a capital lease and recorded as property, plant and equipment. The Company determined that the cost of the new sub-lease would be amortized on a straight-line basis over a 25-year estimated useful life.

In connection with the above-mentioned lease, the Company estimated that it had an asset retirement obligation at the end of the initial five-year lease term in the amount of $306,400. The Company discounted the asset retirement obligation using an 8% discount rate and recorded an asset retirement obligation in the amount of $205,659 as of December 31, 2016, which is included in leasehold improvements and was being depreciated over the five-year term of the lease (see Note 15). As of December 31, 2017, the Company determined that it was probable that it would exercise the additional five-year option provided for in the sub-lease. Therefore, the company remeasured the asset retirement obligation using the remaining eight-year new sub-lease term and recorded a reduction in the asset retirement obligation of $75,011 recorded in leasehold improvements. On December 14, 2018, upon execution of the new sub-lease, the Company remeasured the asset retirement obligation using the remaining 25-year estimated useful life and recorded a reduction in the asset retirement obligation of $99,090 recorded in leasehold improvements.

In connection with two operating leases entered into in July 2018, the Company estimated that it had asset retirement obligations at the end of the eight-year terms in the amount of $140,129. The Company discount the asset retirement obligation using an 8% discount rate and recorded an asset retirement obligation in the aggregate amount of $69,286, which is included in leasehold improvements and is being depreciated over the eight-year term of the lease.

Capitalized leases in the amount of $95,880 are included in computer and office equipment at December 31, 2018 and 2017, and accumulated depreciation of $62,912 and 34,552 at December 31, 2018 and 2017, respectively.

A capitalized lease in the amount of $7,150,611 is included in capitalized leasehold interest at December 31, 2018 and accumulated depreciation of $6,928 at December 31, 2018.

Depreciation expense was $2,052,948 and $679,177 for the years ended December 31, 2018 and 2017 respectively.