Revenues

Product Revenues

The Company’s net product revenues consisted of the following for the years ended December 31:



	2017		2016		2015
Products:
Acetadote	$	6,576,720	$	7,214,341	$	8,489,167
Omeclamox-Pak	1,761,868		2,536,027		3,037,078
Kristalose	11,455,805		15,898,760		15,733,327
Vaprisol	1,576,222		1,857,838		2,641,484
Caldolor	4,178,443		4,132,833		3,112,128
Ethyol	10,835,038		838,386		—
Totect	3,992,467		—		—
Total net product revenues	$	40,376,563	$	32,478,185	$	33,013,184

The Company acquired rights to Ethyol and Totect, as discussed in Note 3. Ethyol contributed to net revenue during 2017 and 2016 and Totect contributed to net revenue during 2017.

Cumberland supplies Perrigo Company ("Perrigo") with an Authorized Generic version of the Company's Acetadote product. The Company's revenue generated by sales of its Authorized Generic distributed by Perrigo is included in the Acetadote product revenue presented above. The Company's share of Authorized Generic revenue was $4.6 million, $4.8 million and $4.5 million during 2017, 2016 and 2015, respectively.

The allowances in accounts receivable for chargebacks, cash discounts and damaged goods were $0.5 million at December 31, 2017 and $0.4 million at December 31, 2016, and the accruals for rebates, product returns and certain administrative and service fees included in other current liabilities were $4.7 million and $4.1 million, at December 31, 2017 and 2016, respectively.

Other Revenues

The Company has entered into agreements, beginning in 2012, with international partners for commercialization of the Company's products. The international agreements provide that each of the partners are responsible for seeking regulatory approvals for the products, and following approvals, each partner will handle ongoing distribution and sales in the respective international territories. The Company maintains responsibility for the intellectual property and product formulations. Under the international agreements, the Company is entitled to receive non-refundable up-front payments at the time the agreements are entered into and milestone payments upon the partners' achievement of defined regulatory approvals and sales milestones. The Company will recognize revenue for these substantive milestones using the milestone method. The Company is also entitled to receive royalties on future sales of the products under the agreements. The international agreements provide for $1.5 million in non-refundable up-front payments, milestone payments of up to $2.4 million of milestone payments related to regulatory approvals and up to $4.6 million in payments related to product sales. As of December 31, 2017, the Company has recognized a cumulative $1.5 million in upfront payments as other revenue and has recognized $0.1 million revenue related to the milestone payments associated with these international agreements.

Other revenues during 2017, 2016 and 2015 also includes revenue generated by CET through grant funding from federal Small Business grant programs, and lease income generated by CET’s Life Sciences Center and contract services. The Life Sciences Center is a research center that provides scientists with access to flexible lab space and other resources to develop biomedical products. Grant revenue from SBIR/STTR programs totaled approximately $0.2 million, $0.1 million, and $0.2 million for the years ending December 31, 2017, 2016 and 2015, respectively.