Revenue

12 Months Ended

Dec. 31, 2020

Revenue

Revenue

10.  Revenue

	Year ended December 31,
(in thousands)	2018		2019		2020
Product revenue, net	$	—	$	1,538	$	108
Collaboration revenues		6,500		6,210		2,756
Research premium		2,594		1,311		1,227
Government grants		562		422		936
Total	$	9,656	$	9,481	$	5,027

Collaboration revenues for the year ended December 31, 2019 includes a $1.0 million upfront payment under the Sunovion License Agreement received in April 2019, and a $5.0 million milestone payment under the Sinovant License Agreement (see Note 16). Collaboration revenues for the year ended December 31, 2020 includes a $0.5 million regulatory milestone payment from Sunovion, $1.8 million for the Company´s share of revenues associated with the SIVEXTRO distribution agreement with Merck & Co., Inc., as well as collaboration revenues associated with the

restructuring of the Company´s license agreement with Sinovant. The Company will recognize the $1.0 million payment received as collaboration revenue in the consolidated statements of operations over the estimated period the manufacturing collaboration and regulatory support will be provided to Sinovant.

The Company sells its products to pharmaceutical wholesalers/distributors (i.e. the Company´s customers). The Company´s wholesalers/distributors in turn sell the Company´s products directly to clinics, hospitals, and private practices. Revenue from the Company´s product sales is recognized as physical delivery of product occurs (when the Company´s customer obtains control of the product), in return for agreed-upon consideration.

For the year ended December 31, 2020 product revenues, gross were $0.5 million, respectively. The Company´s product revenues, gross (i.e., delivered units multiplied by the contractual price per unit) are reduced by the corresponding gross-to-net, or GTN, estimates, resulting in the Company´s reported “product revenues, net” in the accompanying consolidated statements of operations. These GTN estimates are based upon information received from external sources (such as written or oral information obtained from the Company´s customers with respect to their period-end inventory levels and sales to end-users during the period), in combination with management’s informed judgments. Due to the inherent uncertainty of these estimates, the actual amount incurred may be materially above or below the amount initially estimated when product revenues are originally recorded, then requiring prospective adjustments to our reported product revenues, net.

The following tables summarizes GTN adjustments for the periods presented:

	Year Ended December 31,
(in thousands)	2019		2020
Product revenue, gross	$	2,173	$	484
GTN accruals
Chargebacks and cash discounts		48		16
Medicaid and Medicare rebates		223		52
Other returns, rebates, discounts and adjustments		364		115
Total GTN accruals		(635)		(183)
Product revenue		1,538		301
Adjustments to prior period accruals
Returns reserve (1)		—		(421)
GTN accrual adjustments		—		228
Product revenue, net	$	1,538	$	108

(1) As of December 31, 2020, the Company recorded a returns reserve adjustment for slow-moving inventory, representing 50% of XENLETA IV inventory held at its Specialty Distributors, as well as an adjustment for returns from a single mail order specialty pharmacy.