CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current Assets:
Cash and Cash Equivalents	$ 22,724	$ 11,232
Marketable Securities	30,998	53,151
Accounts and Other Receivables	1,108	1,015
Prepaid and Other Current Assets	1,088	1,300
Total Current Assets	55,918	66,698
Property and Equipment, Net	4,116	4,031
Operating Lease Right-of-Use Assets, Net	3,739	3,473
Intangible Assets, Net	48,690	48,690
Other Assets	41	41
Total Assets	112,504	122,933
Current Liabilities:
Accounts Payable	1,609	1,174
Accrued Expenses	5,648	6,499
Current Portion of Operating Lease Liabilities	1,682	1,944
Current Portion of Long-Term Liabilities	1,993	2,026
Total Current Liabilities	10,932	11,643
Long-Term Portion of Operating Lease Liabilities	2,106	1,713
Other Long-Term Liabilities	15,763	15,551
Total Liabilities	28,801	28,907
Commitments and Contingent Liabilities (Note 14)
Stockholders' Equity:
Convertible Preferred Stock, $.01 Par Value; 3,000,000 Shares Authorized; No Shares Issued and Outstanding at March 31, 2020 and December 31, 2019, Respectively
Common Stock, $.001 Par Value; 297,000,000 Shares Authorized; 17,730,802 and 16,972,077 Shares Issued and Outstanding at March 31, 2020 and December 31, 2019, Respectively	18	17
Additional Paid-In Capital	1,107,029	1,104,706
Accumulated Other Comprehensive Income	2,597	2,619
Accumulated Deficit	(1,025,941)	(1,013,316)
Total Stockholders' Equity	83,703	94,026
Total Liabilities and Stockholders' Equity	$ 112,504	$ 122,933