XML 46 R28.htm IDEA: XBRL DOCUMENT
v3.19.1

Note 10 - Stock-based Compensation (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Notes Tables |
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block] |
|  | Year ended December 31, |
|  | 2018 |  |  | 2017 |
Research and development |  | $ | 62,161 |  |  | $ | 674,643 |
General and administrative |  |  | 1,159,430 |  |  |  | 716,425 |
Total stock-based compensation expense |  | $ | 1,221,591 |  |  | $ | 1,391,068 |
Share-based Compensation, Stock Options, Activity [Table Text Block] |
|  | Number of Options |  |  | Weighted average exercise price per share |  |  | Weighted average remaining contractual life (in years) |  |  | Aggregate Intrinsic Value |
Balance at January 1, 2017 |  |  | 147,214 |  |  | $ | 121.37 |  |  |  |  |  |  |  |  |
Granted |  |  | 23,345 |  |  |  | 36.92 |  |  |  |  |  |  |  |  |
Expired |  |  | (98 | ) |  |  | 225.00 |  |  |  |  |  |  |  |  |
Balance at January 1, 2018 |  |  | 170,461 |  |  | $ | 109.74 |  |  |  | 7.13 |  |  | $ | 4,746 |
Granted |  |  | 44,005 |  |  |  | 15.37 |  |  |  |  |  |  |  |  |
Forfeited |  |  | (10,583 | ) |  |  | 131.25 |  |  |  |  |  |  |  |  |
Expired |  |  | (147 | ) |  |  | 256.50 |  |  |  |  |  |  |  |  |
Outstanding at December 31, 2018 |  |  | 203,736 |  |  | $ | 88.14 |  |  |  | 6.70 |  |  | $ | 143 |
Exercisable at December 31, 2018 |  |  | 167,585 |  |  | $ | 101.69 |  |  |  | 6.25 |  |  | $ | 143 |
Vested and expected to vest at December 31, 2018 |  |  | 203,736 |  |  | $ | 88.14 |  |  |  | 6.70 |  |  | $ | 143 |
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] |
|  | 2018 |  |  | 2017 |
Expected term (in years) |  | 5.27 | — | 5.66 |  |  | 5.27 | — | 6.00 |
Risk-free interest rate |  | 2.3% | — | 2.8% |  |  | 1.8% | — | 2.4% |
Expected volatility |  | 113.6% | — | 115.0% |  |  | 109.8% | — | 136.7% |
Dividend yield |  | — | — | — |  |  | — | — | — |

X
- Definition Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 + Details
Name: | us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_TableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration