INVENTORIES

Inventories consist of the following as of:

(in thousands)	June 30, 2017		December 31, 2016
Raw materials	$	17,183	$	14,138
Packaging materials		1,279		930
Work-in-progress		776		477
Finished goods⁽¹⁾		23,279		10,812
		42,517		26,357
Reserve for excess/obsolete inventories		(210)		(174)
Inventories, net	$	42,307	$	26,183

⁽¹⁾Includes finished goods acquired in asset purchases (Note 12).

Vendor Concentration

We source the raw materials for our products, including active pharmaceutical ingredients (“API”), from both domestic and international suppliers. Generally, only a single source of API is qualified for use in each product due to the cost and time required to validate a second source of supply. As a result, we are dependent upon our current vendors to reliably supply the API required for ongoing product manufacturing. During the three months ended June 30, 2017, we purchased approximately 27% of our inventory (exclusive of inventory acquired in asset purchases (Note 12)) from two suppliers. As of June 30, 2017, the amounts payable to these suppliers was immaterial. During the six months ended June 30, 2017, we purchased approximately 18% of our inventory (exclusive of inventory acquired in asset purchases (Note 12)) from one supplier. As of June 30, 2017, the amounts payable to this supplier was immaterial. During the three months ended June 30, 2016, we purchased approximately 48% of our inventory from four suppliers. During the six months ended June 30, 2016, we purchased approximately 29% of our inventory from two suppliers.