Stockholders' Equity | Stockholders' Equity Equity Plans The Company has used long-term incentive plans for the purpose of granting equity awards to employees of the Company, including officers, and nonemployees, including consultants and nonemployee members of the Company's board of directors (collectively, "Participants"). The Participants may receive awards as determined by a committee of independent members of the Company's board of directors or, to the extent authorized by such committee with respect to certain Participants, a duly authorized employee (collectively, the "Committee"). The incentive plan currently used by the Company is the 2018 Equity Incentive Compensation Plan (the "2018 Plan"), which was adopted by the stockholders of the Company in June 2018, with 1,500,000 shares authorized for issuance thereunder, plus any shares currently awarded under the 2015 Equity Compensation Plan (the "2015 Plan") or the Amended and Restated 2009 Equity Compensation Plan (the "2009 Plan") that are not issued due to their subsequent forfeiture, cancellation, or other settlement thereof. Concurrent with the adoption of the 2018 Plan, no future awards will occur under the 2015 Plan or the 2009 Plan. The awards that may be made under the 2018 Plan include: (a) incentive stock options and nonqualified stock options, (b) shares of restricted stock, (c) restricted stock units, and (d) other kinds of equity-based compensation awards. All stock options under the 2015 Plan and 2009 Plan were granted and the 2018 Plan are granted at the fair market value of the common stock at the grant date. Stock options vest either on the date of grant, ratably over a period determined at time of grant, or upon the accomplishment of specified business milestones, and generally expire 2 , 3 , or 10 years from the grant date depending on the status of the recipient as a nonemployee, employee or director of the Company. As of December 31, 2018 , there were 1,054,411 shares available for future grants under the 2018 Plan. No additional awards may be made under the 2015 Plan or the 2009 Plan. The Company adopted an employee stock purchase plan effective January 1, 2013 and authorized 50,000 shares under the plan (the "2012 ESPP"). The plan has two six -month offering periods per year under which eligible employees may contribute up to 15% of their compensation toward the purchase of the Company's common stock per offering period (with a $25,000 cap per calendar year). The employee's purchase price is equal to (i) 85% of the closing price of a share of the Company's common stock on the enrollment date of such offering period or (ii) 85% of the closing price of a share of the Company's common stock on the Exercise Date of such Offering Period, whichever is lower. In May 2017, the Company's stockholders approved an amendment and restatement to the 2012 ESPP (the "2017 ESPP") in order to effect an increase of authorized shares from 50,000 to 100,000 . In June 2018, the Company's stockholders approved an amendment to the 2017 ESPP (the " Amended 2017 ESPP") in order to effect an increase of authorized shares from 100,000 to 500,000 . During the year ended December 31, 2018 , 26,875 shares were issued under the 2017 ESPP. At December 31, 2018 , the Company had 405,655 shares of the Company's common stock available for future grant in connection with this plan. Equity Issuances September 2016 Private Placement In September 2016, the Company entered into Securities Purchase Agreements with certain accredited investors with whom it had a substantive, pre-existing relationship, including certain existing stockholders, for the sale by the Company of its common stock, at a purchase price of $4.72 per share. The investments were placed in two tranches whereby (i) $6.6 million was received and 1.4 million shares of common stock were issued in 2016 upon an initial closing, and (ii) $4.4 million was received and 0.9 million shares of common stock were issued in 2017, which was subject to certain closing conditions, including the enrollment of 70 subjects in the Company’s Phase 2 CLBS03 clinical trial, in a second closing. Aspire Purchase Agreement In November 2015, the Company entered into a common stock purchase agreement (the "Purchase Agreement") with Aspire Capital Fund, LLC, an Illinois limited liability company (“Aspire Capital”), which provided that, subject to certain terms and conditions and Nasdaq rules, Aspire Capital was committed to purchase up to an aggregate of $30 million of shares (limited to a maximum of approximately 1.1 million shares, unless stockholder approval was obtained or certain minimum sale price levels were reached) of the Company's common stock over a 24 -month term. The Company issued 319,776 shares of under the Purchase Agreement for gross proceeds of $1.5 million , which Purchase Agreement expired in November 2017. Common Stock Sales Agreement In February 2018, the Company entered into a common stock sales agreement (the "Sales Agreement") with H.C. Wainwright & Co., LLC ("HCW") as sales agent, in connection with an “at the market offering” under which the Company from time to time may offer and sell shares of its common stock, having an aggregate offering price of up to $12.0 million (limited to a maximum of 2,790,697 shares). Subject to the terms and conditions of the Sales Agreement, HCW will use its commercially reasonable efforts consistent with its normal trading and sales practices to sell the shares from time to time, based upon the Company's instructions, including any price, time or size limits specified by the Company. The Company has provided HCW with customary indemnification rights, and HCW is entitled to a commission at a fixed commission rate equal to 3.0% of the gross proceeds per share sold. The Company has no obligation to sell any of the shares and may at any time suspend sales under the Sales Agreement or terminate the Sales Agreement. The Sales Agreement will terminate upon the sale of all of the shares under the Sales Agreement unless terminated earlier by either party as permitted under the Sales Agreement. In August 2018, the Company entered into an amendment to the Sales Agreement to reflect that the shares will be issued pursuant to a Registration Statement on Form S-3 (Registration No. 333-226319) that was declared effective in August 2018 and that replaced the Company’s previously effective shelf registration statement. In connection with the amendment, the number of shares of common stock that may be sold pursuant to the Sales Agreement was increased from an aggregate offering amount of $12.0 million to $25.0 million (limited to a maximum of 4,921,260 shares). All other provisions of the Sales Agreement remained unchanged. During the year ended December 31, 2018 , the Company issued 149,041 shares of common stock under the Sales Agreement for net proceeds of $1.0 million . Stock Options and Warrants The following table summarizes the activity for stock options and warrants for the year ended December 31, 2018 : Stock Options Warrants Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (In Thousands) Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (In Thousands) Outstanding at December 31, 2017 1,072,499 $ 33.50 4.76 $ 0.1 209,818 $ 53.20 0.95 $ — Changes during the Year: Granted 157,360 $ 4.00 — $ — Exercised (77,498 ) $ 4.60 — $ — Forfeited (3,030 ) $ 3.80 — $ — Expired (130,801 ) $ 32.50 (179,818 ) $ 60.40 Outstanding at December 31, 2018 1,018,530 $ 30.50 5.30 $ 3.3 30,000 $ 5.90 4.19 $ — Vested at December 31, 2018 or expected to vest in the future 1,008,918 $ 30.80 5.26 $ 3.3 30,000 $ 5.90 4.19 $ — Exercisable at December 31, 2018 895,861 $ 34.20 4.78 $ 3.3 30,000 $ 5.90 4.19 $ — Restricted Stock During the years ended December 31, 2018 and 2017 , the Company issued restricted stock for services as follows ($ in thousands, except share data): 2018 2017 Number of Restricted Stock Issued 91,740 181,908 Value of Restricted Stock Issued $ 347.7 $ 627.7 The weighted average estimated fair value of restricted stock issued for services in the years ended December 31, 2018 and 2017 was $ 3.79 and $3.45 per share, respectively. The fair value of the restricted stock was determined using the Company’s closing stock price on the date of issuance. The vesting terms of restricted stock issuances are generally between one to four years. Restricted Stock Units During the years ended December 31, 2018 and 2017 , the Company issued restricted stock units for services as follows ($ in thousands, except share data): 2018 2017 Number of Restricted Stock Units Issued 139,497 10,260 Value of Restricted Stock Units Issued $ 711.9 $ 55.1 The weighted average estimated fair value of restricted stock issued for services in the years ended December 31, 2018 and 2017 was $5.10 and $5.37 per share, respectively. The fair value of the restricted stock units was determined using the Company’s closing stock price on the date of issuance. The vesting terms of restricted stock unit issuances are generally one year, or upon the achievement of performance-based milestones. |