Commitments and Contingencies

Lease Commitment Summary

The following table presents future minimum commitments of the Company due under non-cancelable operating leases with original or remaining terms in excess of one year as of December 31, 2018. The Company’s operating lease obligations are primarily related to its principal executive office and research facility in Durham, North Carolina, and its corporate offices in Irvine, California, and Bedminster, New Jersey.

Minimum lease payments under operating leases were as follows at December 31, 2018:



(in thousands)
2019	$	4,283
2020	4,855
2021	4,278
2022	1,643
2023	1,438
2024 and thereafter	6,698
Total minimum lease payments	$	23,195

Minimum expected lease payments related to the Company’s manufacturing plant in Athlone, Ireland, are not reflected in the table above (see Note 7).

Rent expense amounted to $3.5 million, $2.0 million and $1.4 million for the years ended December 31, 2018, 2017 and 2016, respectively, and is reflected in selling, general and administrative expenses, pre-approval commercial manufacturing and research and development expenses as determined by the underlying activities occurring at each of the Company’s locations.

Milestone Payments

In association with the Envisia asset acquisition (see Note 1), contingent milestone payments of up to $45.0 million may be due, subject to achievement of certain product regulatory approvals using the IPR&D assets acquired, if achieved within the 15-year milestone period. Further, the Collaboration Agreement with DSM (see Note 1) includes contingent payments of up to $75 million that may be due to DSM upon the achievement of certain development and regulatory milestones. These contingent milestone payments are recognized only when the contingency is resolved (the milestone is achieved) and the consideration is paid or becomes payable.

Litigation

The Company may periodically become subject to legal proceedings and claims arising in connection with its business. The Company is not a party to any known litigation, is not aware of any material unasserted claims and does not have contingency reserves established for any litigation liabilities.