Annual report pursuant to Section 13 and 15(d)

Consolidated Statements of Cash Flows

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
Consolidated Statements of Cash Flows (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net loss	$ (35,726,669)us-gaap_NetIncomeLoss	$ (42,699,458)us-gaap_NetIncomeLoss	$ (29,157,204)us-gaap_NetIncomeLoss
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization of property and equipment	487,906	400,304	198,822
Amortization of patents and trademarks	12,277us-gaap_AmortizationOfIntangibleAssets	3,877us-gaap_AmortizationOfIntangibleAssets	1,400us-gaap_AmortizationOfIntangibleAssets
Loss on disposal and abandonment of assets	31,794us-gaap_GainLossOnDispositionOfAssets	1,160us-gaap_GainLossOnDispositionOfAssets	2,534us-gaap_GainLossOnDispositionOfAssets
Inventory Write-down	539,027us-gaap_InventoryWriteDown	0us-gaap_InventoryWriteDown	0us-gaap_InventoryWriteDown
Amortization of debt discount and debt offering costs	844,250	765,263	544,517
Stock compensation expense	1,634,162us-gaap_ShareBasedCompensation	2,908,269us-gaap_ShareBasedCompensation	2,304,118us-gaap_ShareBasedCompensation
Equity in loss of R-NAV, LLC	523,809	0	0
Change in fair value of financial instruments	1,342,389us-gaap_UnrealizedGainLossOnDerivatives	112,073us-gaap_UnrealizedGainLossOnDerivatives	(32,110)us-gaap_UnrealizedGainLossOnDerivatives
Loss on extinguishment of debt	2,610,196	1,372,266	0
Issuance of common stock for payment of milestone and sublicense fees	0	166,000	1,146,000
Other	150,761	71,209	61,928
Change in operating assets and liabilities:
Accounts receivable	334,082	(1,042,280)	6,499
Inventory	761,024us-gaap_IncreaseDecreaseInInventories	(1,934,936)us-gaap_IncreaseDecreaseInInventories	524,049us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other assets	(476,860)	84,493	(385,125)
Accounts payable	(944,850)	1,003,515	736,109
Accrued liabilities and other liabilities	(1,250,047)	3,176,170	125,144
Net cash used in operating activities	(29,126,749)	(35,612,075)	(23,923,319)
Cash flows from investing activities:
Purchases of equipment	(1,114,448)	(1,239,666)	(663,348)
Patent and trademark costs	(77,184)	(52,701)	(8,460)
Investment in R-NAV, LLC	(333,334)us-gaap_PaymentsToAcquireInvestments	0us-gaap_PaymentsToAcquireInvestments	0us-gaap_PaymentsToAcquireInvestments
Net cash used in investing activities	(1,524,966)	(1,292,367)	(671,808)
Cash flows from financing activities:
Proceeds from issuance of common stock, net	87,984	41,303,750	2,724,189
Payment of common stock issuance costs	0	(1,752,932)	0
Payment for common stock repurchased from executives	0	0	(100,875)
Payment of tax withholdings related to stock-based compensation	(130,537)	(659,018)	(8,765)
Payment of preferred stock dividends	0	0	(100,000)
Proceeds from notes payable	30,000,000us-gaap_ProceedsFromNotesPayable	29,000,000us-gaap_ProceedsFromNotesPayable	4,000,000us-gaap_ProceedsFromNotesPayable
Payment of debt issuance costs	(1,763,526)us-gaap_PaymentsOfDebtIssuanceCosts	(1,177,293)us-gaap_PaymentsOfDebtIssuanceCosts	(153,949)us-gaap_PaymentsOfDebtIssuanceCosts
Principal payments on notes payable	(25,000,000)us-gaap_RepaymentsOfNotesPayable	(5,982,155)us-gaap_RepaymentsOfNotesPayable	(1,285,046)us-gaap_RepaymentsOfNotesPayable
Payments under capital leases	(2,226)	(7,448)	(5,867)
Net cash provided by financing activities	3,191,695	60,724,904	5,069,687
Net (decrease) increase in cash	(27,460,020)	23,820,462	(19,525,440)
Cash, beginning of year	32,939,026	9,118,564	28,644,004
Cash, end of year	$ 5,479,006	$ 32,939,026	$ 9,118,564