Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2019	Aug. 06, 2019
Document and Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Entity Registrant Name	GALECTIN THERAPEUTICS INC
Entity Central Index Key	0001133416
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Trading Symbol	GALT
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		56,631,304
Entity Interactive Data Current	Yes
Entity Small Business	true
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Address, State or Province	GA
Title of 12(b) Security	Common Stock
Security Exchange Name	NASDAQ

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 52,043	$ 8,253
Prepaid expenses and other current assets	652	579
Total current assets	52,695	8,832
Other	317	174
Total assets	53,012	9,006
Current liabilities:
Accounts payable	396	297
Accrued expenses and other	857	1,512
Accrued dividends payable	66	299
Total current liabilities	1,319	2,108
Other liabilities	72	0
Total liabilities	1,391	2,108
Commitments and contingencies (Note 10)
Stockholders' equity:
Undesignated stock, $0.01 par value; 20,000,000 shares authorized, 20,000,000 designated at June 30, 2019 and December 31, 2018, respectively	0	0
Common stock, $0.001 par value; 100,000,000 shares authorized at June 30, 2019 and December 31, 2018, 56,591,278 and 41,190,905 issued and outstanding at June 30, 2019 and December 31, 2018, respectively	56	41
Additional paid-in capital	257,678	194,130
Retained deficit	(208,373)	(196,215)
Total stockholders' equity	49,898	5,175
Total liabilities, redeemable convertible preferred stock and stockholders' equity	53,012	9,006
Series C super dividend redeemable convertible preferred stock
Current liabilities:
Convertible preferred stock, value	1,723	1,723
Series A 12% convertible preferred stock
Stockholders' equity:
Convertible preferred stock, value	537	537
Series B-1 12% convertible preferred stock
Stockholders' equity:
Convertible preferred stock, value	0	1,761
Series B-2 12% convertible preferred stock
Stockholders' equity:
Convertible preferred stock, value	0	3,697
Series B-3 8% convertible preferred stock
Stockholders' equity:
Convertible preferred stock, value	$ 0	$ 1,224

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Undesignated stock, par value	$ 0.01	$ 0.01
Undesignated stock, shares authorized	20,000,000	20,000,000
Undesignated stock, shares designated	20,000,000	20,000,000
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, issued	56,591,278	41,190,905
Common stock, outstanding	56,591,278	41,190,905
Series C super dividend redeemable convertible preferred stock
Convertible preferred stock, shares authorized	1,000	1,000
Convertible preferred stock, shares issued	176	176
Convertible preferred stock, shares outstanding	176	176
Convertible preferred stock, redemption value	$ 8,758,000
Convertible preferred stock, liquidation value	$ 1,760,000
Series A 12% convertible preferred stock
Convertible preferred stock, shares authorized	1,742,500	1,742,500
Convertible preferred stock, issued	1,327,500	1,327,500
Convertible preferred stock, outstanding	1,327,500	1,327,500
Convertible preferred stock, liquidation value	$ 1,327,500
Series B-1 12% convertible preferred stock
Convertible preferred stock, shares authorized	900,000	900,000
Convertible preferred stock, issued	0	900,000
Convertible preferred stock, outstanding	0	900,000
Series B-2 12% convertible preferred stock
Convertible preferred stock, shares authorized	2,100,000	2,100,000
Convertible preferred stock, issued	0	2,100,000
Convertible preferred stock, outstanding	0	2,100,000
Series B-3 8% convertible preferred stock
Convertible preferred stock, shares authorized	2,508,000	2,508,000
Convertible preferred stock, issued	0	2,508,000
Convertible preferred stock, outstanding	0	2,508,000

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Operating expenses:
Research and development	$ 1,522	$ 1,476	$ 2,168	$ 3,774
General and administrative	1,498	2,283	3,219	4,163
Total operating expenses	3,020	3,759	5,387	7,937
Total operating loss	(3,020)	(3,759)	(5,387)	(7,937)
Other income (expense):
Interest income	43	4	57	8
Interest expense	(21)	(85)	(43)	(169)
Total other income (expense)	22	(81)	14	(161)
Net loss	(2,998)	(3,840)	(5,373)	(8,098)
Preferred stock dividends	(67)	(268)	(163)	(553)
Warrant modification (Note 9)	0	0	(6,622)	0
Net loss applicable to common stockholders	$ (3,065)	$ (4,108)	$ (12,158)	$ (8,651)
Net loss per common share — basic and diluted	$ (0.06)	$ (0.11)	$ (0.26)	$ (0.23)
Weighted average common shares outstanding — basic and diluted	50,301	38,227	47,653	37,755

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (5,373)	$ (8,098)
Adjustments to reconcile net loss to net cash flows from operating activities:
Payment of preferred stock dividends	(396)	0
Stock-based compensation expense	855	2,630
Amortization of right to use lease asset	18	0
Issuance of common stock for services	0	10
Non-cash interest expense	43	169
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(277)	226
Accounts payable and accrued expenses	(484)	(1,532)
Net cash from operating activities	(5,614)	(6,595)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from issuance of common stock and warrants	49,404	14,039
Net cash flows from financing activities	49,404	14,039
NET INCREASE IN CASH AND CASH EQUIVALENTS	43,790	7,444
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	8,253	3,053
CASH AND CASH EQUIVALENTS, END OF PERIOD	52,043	10,497
NONCASH FINANCING ACTIVITIES:
Payment of preferred stock dividends in common stock	$ 0	$ 554

Condensed Consolidated Statements of Changes in Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Warrants	Series A 12% convertible preferred stock	Series B-1 12% convertible preferred stock	Series B-2 12% convertible preferred stock	Series B-3 8% convertible preferred stock	Series C super dividend redeemable convertible preferred stock	Series A 12% convertible preferred stock	Series A 12% convertible preferred stock Series A Convertible Preferred Stock [Member]	Series B-1 12% convertible preferred stock	Series B-1 12% convertible preferred stock Series B Convertible Preferred Stock [Member]	Series B-2 12% convertible preferred stock	Series B-2 12% convertible preferred stock Series B Convertible Preferred Stock [Member]	Series B-3 8% convertible preferred stock	Series B-3 8% convertible preferred stock Series B Convertible Preferred Stock [Member]	Common Stock	Common Stock Warrants	Common Stock Series A 12% convertible preferred stock	Common Stock Series B-1 12% convertible preferred stock	Common Stock Series B-2 12% convertible preferred stock	Common Stock Series B-3 8% convertible preferred stock	Common Stock Series C super dividend redeemable convertible preferred stock	Common Stock Series B Convertible Preferred Stock [Member]	Common Stock Series A Convertible Preferred Stock [Member]	Additional Paid-In Capital	Additional Paid-In Capital Warrants	Additional Paid-In Capital Series A 12% convertible preferred stock	Additional Paid-In Capital Series B-1 12% convertible preferred stock	Additional Paid-In Capital Series B-2 12% convertible preferred stock	Additional Paid-In Capital Series B-3 8% convertible preferred stock	Additional Paid-In Capital Series C super dividend redeemable convertible preferred stock	Additional Paid-In Capital Series B Convertible Preferred Stock [Member]	Additional Paid-In Capital Series A Convertible Preferred Stock [Member]	Retained Deficit	Retained Deficit Series A 12% convertible preferred stock	Retained Deficit Series B-1 12% convertible preferred stock	Retained Deficit Series B-2 12% convertible preferred stock	Retained Deficit Series B-3 8% convertible preferred stock	Retained Deficit Series C super dividend redeemable convertible preferred stock
Stockholders' Equity (Deficit), Balance (in shares) at Dec. 31, 2017								1,377,500		900,000		2,100,000		2,508,000		35,789,388
Stockholders' Equity (Deficit), Balance at Dec. 31, 2017	$ (530)							$ 557		$ 1,761		$ 3,697		$ 1,224		$ 36									$ 173,363									$ (181,168)
Temporary Equity, Balance (in shares) at Dec. 31, 2017							176
Temporary Equity, Balance at Dec. 31, 2017							$ 1,723
Convertible preferred stock dividend																											$ 66	$ 101	$ 237	$ 94	$ 56				$ (66)	$ (101)	$ (237)	$ (94)	$ (56)
Convertible preferred stock dividend (in shares)																		13,775	18,879	44,051	17,478	11,899
Issuance of common stock	5,242															$ 1									5,241
Issuance of common stock (in shares)																618,614
Issuance of common stock for exercise of warrants and options		$ 8,797															$ 4									$ 8,793
Issuance of common stock for exercise of warrants and options ( in shares)																	4,107,187
Issuance of common stock from Series A conversion									$ (10)																								$ 10
Issuance of common stock from Series A conversion (in shares)									(25,000)															4,257
Conversion of Series B Convertible Preferred to common									$ (10)																								10
Conversion of Series B Convertible Preferred to common (in shares)									(25,000)															4,257
Net loss	(8,098)																																	(8,098)
Temporary Equity, Balance (in shares) at Jun. 30, 2018							176
Temporary Equity, Balance at Jun. 30, 2018							$ 1,723
Issuance of common stock for services	10																								11
Issuance of common stock for services (in shares)																2,655
Stock-based compensation expense	2,630																								2,630
Stockholders' Equity (Deficit), Balance (in shares) at Jun. 30, 2018								1,352,500		900,000		2,100,000		2,508,000		40,628,183
Stockholders' Equity (Deficit), Balance at Jun. 30, 2018	8,052							$ 547		$ 1,761		$ 3,697		$ 1,224		$ 41									190,602									(189,820)
Stockholders' Equity (Deficit), Balance (in shares) at Mar. 31, 2018								1,377,500		900,000		2,100,000		2,508,000		37,645,971
Stockholders' Equity (Deficit), Balance at Mar. 31, 2018	925							$ 557		$ 1,761		$ 3,697		$ 1,224		$ 38									179,359									(185,711)
Convertible preferred stock dividend			$ (42)				$ (26)																					$ 47	$ 110	$ 44					(42)	(47)	(110)	(44)	(26)
Convertible preferred stock dividend (in shares)																			7,421	17,315	6,870
Issuance of common stock	5,242															$ 1									5,241
Issuance of common stock (in shares)																618,614
Issuance of common stock for exercise of warrants and options		4,346															$ 2									4,344
Issuance of common stock for exercise of warrants and options ( in shares)																	2,326,709
Issuance of common stock from Series A conversion									$ (10)																								10
Issuance of common stock from Series A conversion (in shares)									(25,000)															4,257
Conversion of Series B Convertible Preferred to common									$ (10)																								$ 10
Conversion of Series B Convertible Preferred to common (in shares)									(25,000)															4,257
Net loss	(3,840)																																	(3,840)
Temporary Equity, Balance (in shares) at Jun. 30, 2018							176
Temporary Equity, Balance at Jun. 30, 2018							$ 1,723
Issuance of common stock for services	4																								4
Issuance of common stock for services (in shares)																1,026
Stock-based compensation expense	1,443																								1,443
Stockholders' Equity (Deficit), Balance (in shares) at Jun. 30, 2018								1,352,500		900,000		2,100,000		2,508,000		40,628,183
Stockholders' Equity (Deficit), Balance at Jun. 30, 2018	8,052							$ 547		$ 1,761		$ 3,697		$ 1,224		$ 41									190,602									(189,820)
Stockholders' Equity (Deficit), Balance (in shares) at Dec. 31, 2018								1,327,500		900,000		2,100,000		2,508,000		41,190,905
Stockholders' Equity (Deficit), Balance at Dec. 31, 2018	5,175							$ 537		$ 1,761		$ 3,697		$ 1,224		$ 41									194,130
Temporary Equity, Balance (in shares) at Dec. 31, 2018							176
Temporary Equity, Balance at Dec. 31, 2018							$ 1,723
Convertible preferred stock dividend	(53)		(80)	$ (6)	$ (15)	$ (9)	$ (53)																											(196,215)	(80)	$ (6)	$ (15)	$ (9)	(53)
Issuance of common stock	$ 46,754															$ 10									46,744
Issuance of common stock (in shares)																10,883,394
Issuance of common stock for exercise of warrants and options		2,650															$ 1									2,649
Issuance of common stock for exercise of warrants and options ( in shares)	142,543																727,633
Issuance of common stock from Series A conversion											$ (1,761)		$ (3,697)		$ (1,224)								$ 4									$ 6,678
Issuance of common stock from Series A conversion (in shares)											(900,000)		(2,100,000)		(2,508,000)								3,789,346
Conversion of Series B Convertible Preferred to common											$ (1,761)		$ (3,697)		$ (1,224)								$ 4									$ 6,678
Conversion of Series B Convertible Preferred to common (in shares)											(900,000)		(2,100,000)		(2,508,000)								3,789,346
Warrant modification (Note 9)																									6,622									(6,622)
Net loss	$ (5,373)																																	(5,373)
Temporary Equity, Balance (in shares) at Jun. 30, 2019							176
Temporary Equity, Balance at Jun. 30, 2019							$ 1,723
Issuance of common stock for services	0
Stock-based compensation expense	855																								855
Stockholders' Equity (Deficit), Balance (in shares) at Jun. 30, 2019								1,327,500		0		0		0		56,591,278
Stockholders' Equity (Deficit), Balance at Jun. 30, 2019	49,898							$ 537		$ 0		$ 0		$ 0		$ 56									257,678									(208,373)
Stockholders' Equity (Deficit), Balance (in shares) at Mar. 31, 2019								1,327,500								45,594,411
Stockholders' Equity (Deficit), Balance at Mar. 31, 2019	5,119							$ 537								$ 45									209,845									(205,308)
Convertible preferred stock dividend			$ (40)				$ (27)																												$ (40)				$ (27)
Issuance of common stock	44,889															$ 10									44,879
Issuance of common stock (in shares)																10,488,161
Issuance of common stock for exercise of warrants and options		$ 2,512															$ 1									$ 2,511
Issuance of common stock for exercise of warrants and options ( in shares)																	508,706
Net loss	(2,998)																																	(2,998)
Temporary Equity, Balance (in shares) at Jun. 30, 2019							176
Temporary Equity, Balance at Jun. 30, 2019							$ 1,723
Stock-based compensation expense	443																								443
Stockholders' Equity (Deficit), Balance (in shares) at Jun. 30, 2019								1,327,500		0		0		0		56,591,278
Stockholders' Equity (Deficit), Balance at Jun. 30, 2019	$ 49,898							$ 537		$ 0		$ 0		$ 0		$ 56									$ 257,678									$ (208,373)

Basis of Presentation

6 Months Ended

Jun. 30, 2019

Basis of Presentation

1. Basis of Presentation

Galectin Therapeutics Inc. (the “Company”) is a clinical stage biopharmaceutical company that is applying its leadership in galectin science and drug development to create new therapies for fibrotic disease, skin diseases and cancer. These candidates are based on the Company’s targeting of galectin proteins which are key mediators of biologic and pathologic function. These compounds also may have application for drugs to treat other diseases and chronic health conditions.

The unaudited condensed consolidated financial statements as reported in this Quarterly Report on Form

10-Q

reflect all adjustments which are, in the opinion of management, necessary to present fairly the financial position of the Company as of June 30, 2019 and the results of its operations for the three and six months ended June 30, 2019 and 2018 and its cash flows for the six months ended June 30, 2019 and 2018. All adjustments made to the interim financial statements include all those of a normal and recurring nature. Amounts presented in the condensed consolidated balance sheet as of December 31, 2018 are derived from the Company’s audited consolidated financial statements as of that date, but do not include all of the information and footnotes required by accounting principles generally accepted in the United States of America for complete financial statements. The Company considers events or transactions that occur after the balance sheet date but before the financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated through the date these financial statements are available to be issued. The results for interim periods are not necessarily indicative of results that may be expected for any other interim period or for the full year. The unaudited condensed consolidated financial statements of the Company should be read in conjunction with its Annual Report on Form

10-K

for the year ended December 31, 2018.

The Company has operated at a loss since its inception and has had no significant revenues. The Company anticipates that losses will continue for the foreseeable future. At June 30, 2019, the Company had $52 million of unrestricted cash and cash equivalents available to fund future operations. The Company believes there is sufficient cash, including availability of the line of credit (see Note 3), to fund currently planned operations at least through December 31, 2020. We expect that we will require more cash to fund our operations after December 31, 2020 and believe we will be able to obtain additional financing. The currently planned operations include estimated costs related to a planned Phase 3 clinical trial through December 31, 2020. While the costs of the trial and general overhead during the Phase 3 trial are expected to be approximately $100 million, the costs and timing of such trial is not yet completely finalized. These costs will require additional funding. There can be no assurance that we will be successful in obtaining financing to support our operations beyond December 31, 2020 or, if available, that any such financing will be on terms acceptable to us. Accordingly, based on the forecasts and estimates underlying our current operating plan, the financial statements do not currently include any adjustments that might be necessary if we are unable to continue as a going concern.

The Company was founded in July 2000, was incorporated in the State of Nevada in January 2001 under the name

“Pro-Pharmaceuticals,

Inc.,” and changed its name to “Galectin Therapeutics Inc.” on May 26, 2011.

Recently Adopted Accounting Standards

The Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”)

No. 2016-02,

Leases (Topic 842),

amended by ASU

2018-11,

Leases

(Topic 842): Targeted Improvements

. The new guidance requires a lessee to recognize assets and liabilities for all leases with lease terms of more than 12 months and provide additional disclosures. The ASU requires adoption using a modified retrospective transition approach with either 1) periods prior to the adoption date being recast or 2) a cumulative-effect adjustment recognized to the opening balance of retained earnings on the adoption date with prior periods not recast. We adopted this standard using a modified retrospective transition approach on January 1, 2019 however we only have one lease related to our office space and it was amended effective January 1, 2019. Therefore, no cumulative-effect adjustment approach was required. See Note 11 for the financial position impact and additional disclosures.

Line of Credit

6 Months Ended

Jun. 30, 2019

Line of Credit

3. Line of Credit

On December 19, 2017, the Company entered into a $10 million Line of Credit arrangement with Richard E. Uihlein, a director and shareholder who had an approximate 7% ownership interest in the Company on a fully-diluted basis at December 31, 2017. Originally, borrowings may be made by the Company through December 31, 2018. Borrowings bear interest at the Applicable Federal Rate for short term loans published by the Internal Revenue Service (2.7% in January 2019). All borrowings and interest were originally due on December 31, 2019 but could be prepaid without penalty. In connection with the Line of Credit agreement, the Company issued to Mr. Uihlein warrants to purchase 1 million shares of the Company’s common stock for $5 per share. Half of the warrants vested at closing of the Line of Credit and the other half vest ratably with borrowings under the agreement. There have been no borrowings under the Line of Credit to date.

On December 20, 2018, the Line of Credit arrangement was extended for one year for both borrowings and maturity. At the time of the conversion of the Series B Convertible Preferred stock into common stock (See Note 9), on January 11, 2019, the Line of Credit arrangement was extended for an additional two years for both borrowings and maturity. After the second amendment to the Line of Credit arrangement, borrowings may be made through December 31, 2021 with repayment due on December 31, 2022. There was no additional consideration or benefits provided to Mr. Uihlein for any of the extensions of the Line of Credit.

The fair value of the 500,000 warrants vested at closing in December 2017 was $696,000 at the date of issuance based on the following assumptions: an expected life of 7 years, volatility of 98%, risk free interest rate of 2.05% and zero dividends. The fair value of the vested warrants was recorded in other current assets and other assets

(non-current)

as a deferred financing cost and were to be amortized on a straight-line basis from December 19, 2017 through December 31, 2019. The remaining unamortized balance of the deferred financing cost on January 11, 2019 was adjusted to be recorded as expense on a straight-line basis through December 31, 2022. Amortization for the six months ended June 30, 2019 and 2018 of $43,000 and $169,000, respectively, was recorded as interest expense. In May 2019, Mr. Uihlein exercised the 500,000 vested warrants and the Company received the proceeds of $2,500,000.

The fair value of warrants that vest in the future based on borrowings will be computed when those borrowings occur and amortized over the remaining period through December 31, 2022 reflecting the second extension.

Stock-Based Compensation

6 Months Ended

Jun. 30, 2019

Stock-Based Compensation

4. Stock-Based Compensation

Following is the stock-based compensation expense related to common stock options, common stock, restricted common stock and common stock warrants:


	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Research and development	$	83	$	627	$	170	$	1,161
General and administrative		360		816		685		1,469

Total stock-based compensation expense	$	443	$	1,443	$	855	$	2,630

The following table summarizes the stock option activity in the Company’s equity incentive plans, including

non-plan

grants to Company executives, from December 31, 2018 through June 30, 2019:


	Shares			Weighted Average Exercise Price
Outstanding, December 31, 2018		2,713,979		$	4.67
Granted		530,000			4.72
Exercised		(142,543	)		1.79
Options forfeited/cancelled		(39,098	)		2.09

Outstanding, June 30, 2019		3,062,338		$	4.85

As of June 30, 2019, there was $1,301,000 of unrecognized compensation related to 468,750 unvested options, which is expected to be recognized over a weighted–average period of approximately 1.07 years. The weighted-average grant date fair value for options granted during the three months ended June 30, 2019 was $3.83. The Company granted 530,000 stock options during the three months ended March 31, 2019.

The fair value of all options granted is determined using the Black-Scholes option-pricing model. The following weighted average assumptions were used:


	Six Months Ended June 30,			Six Months Ended June 30,
	2019			2018
Risk-free interest rate		2.68	%		2.47	%
Expected life of the options		6 years			5.7 years
Expected volatility of the underlying stock		104	%		104	%
Expected dividend rate		0	%		0	%

Fair Value of Financial Instruments

6 Months Ended

Jun. 30, 2019

Fair Value Disclosures [Text Block]

6. Fair Value of Financial Instruments

The Company has certain financial assets and liabilities recorded at fair value. Fair values determined by Level 1 inputs utilize observable data such as quoted prices in active markets. Fair values determined by Level 2 inputs utilize data points other than quoted prices in active markets that are observable either directly or indirectly. Fair values determined by Level 3 inputs utilize unobservable data points in which there is little or no market data, which require the reporting entity to develop its own assumptions. The carrying amounts reflected in the consolidated balance sheets for cash equivalents, accounts payable and accrued expenses approximate their carrying value due to their short-term nature. There were no level 2 or level 3 assets or liabilities at June 30, 2019 or December 31, 2018.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Common Stock

6 Months Ended

Jun. 30, 2019

Equity [Abstract]

Stockholders' Equity Note Disclosure [Text Block]

8. Common Stock

2017 At Market Issuance of Common Stock

On May 19, 2017, the Company entered into an At Market Issuance Sales Agreement (the “2017 At Market Agreement”) with a sales agent under which the Company may issue and sell shares of its common stock having an aggregate offering price of up to $30.0 million from time to time through the sales agent. Sales of the Company’s common stock through the sales agent, if any, will be made by any method that is deemed an “at the market” offering as defined by the U.S. Securities and Exchange Commission. The Company will pay to the sales agent a commission rate equal to 3.0% of the gross proceeds from the sale of any shares of common stock sold through the sales agent under the 2017 At Market Agreement. During the three months ended March 31, 2019, the Company issued 395,233 shares of its common stock under the 2017 At Market Agreement for net proceeds of approximately $1,865,000.

For the three months ended March 31, 2018, the Company has issued a total of 74,476 shares of common stock for dividends on Series A, Series B and Series C Preferred Stock.

Rights Offering

On May 23, 2019, the Company completed an offering of common stock and warrants to its shareholders of record as of April 29, 2019. In the offering, the Company received approximately $44.9 million for the issuance of 10,488,161 shares of common stock and warrants which may be exercised for 2,622,154 shares of common stock. The warrants may be exercised at $7.00 per share of common stock and expire on May 23, 2026. The warrants were valued at approximately $8.2 million as of the issuance, using the closing price of $4.01, a life of 7 years, a volatility of 101% and a risk-free interest rate of 2.33%. Based upon the Company’s analysis of the criteria contained in ASC Topic

815-40,

“Derivatives and Hedging — Contracts in Entity’s Own Equity” the Company has determined that warrants issued in connection with this financing transaction were not derivative liabilities and therefore, were recorded as additional

paid-in

capital.

Preferred Stock Conversion into Common Stock

6 Months Ended

Jun. 30, 2019

Preferred Stock Conversion into Common Stock

9. Preferred Stock Conversion into Common Stock

On January 11, 2019, 10X Fund L.P. (“10X Fund”), converted all of its Series B Convertible Preferred Stock into Common Stock of Galectin Therapeutics. Pursuant to the terms of the conversion, as of January 11, 2019, 10X Fund converted 5,508,000 shares of its Series

B-1,

B-2

and

B-3

Convertible Preferred Stock into 3,789,346 shares of Common Stock of Galectin Therapeutics. All special voting rights and protective provisions that previously benefited the Series B Preferred Stock were extinguished by the conversion to Common Stock.

In connection with the conversion of the Series B Preferred Stock, the Company extended by five years the exercise date of warrants for 3,579,642 shares of Common Stock issued by the Company in connection with sale of the Series

B-1

and Series

B-2

Preferred Stock. Before the extension, the warrants had various expiration dates in 2019 and 2020. The warrant amendments give 10X Fund the right to nominate one director to the Company’s board of directors. Previously, under the now extinguished voting rights of the Series B Preferred, 10X Fund had the right to name two directors and nominate an additional three directors.

The Company has accounted for the modified terms of the warrants pursuant to ASC 718, Stock Compensation, whereby the Company has recognized a charge for the change in fair value of the warrants immediately before and immediately after the modification. In January 2019, the Company recognized a

one-time

non-cash

charge of $6,622,000 related to the extension of the 3,579,642 warrants. The following assumptions were used to value the extension of the warrants immediately before and immediately after the modification: a) immediately before the modification — an expected life range of 0.09 to 1.33 years, volatility of 98%, risk free interest rate range of 2.4% to 2.59% and zero dividends and; b) immediately following the modification — an expected life range of 5.09 to 6.33 years, volatility range of 106%, risk free interest rate range of 2.56% to 2.6% and zero dividends.

Galectin Sciences LLC

6 Months Ended

Jun. 30, 2019

Galectin Sciences LLC

12. Galectin Sciences LLC

In January 2014, we created Galectin Sciences, LLC (the “LLC” or “Investee”), a collaborative joint venture

co-owned

by SBH Sciences, Inc. (“SBH”), to research and develop small organic molecule inhibitors of

galectin-3

for oral administration. The LLC was initially capitalized with a $400,000 cash investment to fund future research and development activities, which was provided by the Company, and specific

in-process

research and development (“IPR&D”) contributed by SBH. The estimated fair value of the IPR&D contributed by SBH, on the date of contribution, was $400,000. Initially, the Company and SBH each had a 50% equity ownership interest in the LLC, with neither party having control over the LLC. Accordingly, from inception through the fourth quarter of 2014, the Company accounted for its investment in the LLC using the equity method of accounting. Under the equity method of accounting, the Company’s investment was initially recorded at cost with subsequent adjustments to the carrying value to recognize additional investments in or distributions from the Investee, as well as the Company’s share of the Investee’s earnings, losses and/or changes in capital. The estimated fair value of the IPR&D contributed to the LLC was immediately expensed upon contribution as there was no alternative future use available at the point of contribution. The operating agreement provides that if either party does not desire to contribute its equal share of funding required after the initial capitalization, then the other party, providing all of the funding, will have its ownership share increased in proportion to the total amount contributed from inception. In the fourth quarter of 2014, after the LLC had expended the $400,000 in cash, SBH decided not to contribute its share of the funding required. Since then, the Company has contributed a total of $1,883,000, including $79,000 for the three months ended June 30, 2019, for expenses of the LLC. Since the end of 2014, SBH has contributed $123,000 for expenses in the LLC. As of June 30, 2019, the Company’s ownership percentage in the LLC was 81.4%. The Company accounts for the interest in the LLC as a consolidated, less than wholly owned subsidiary. Because the LLC’s equity is immaterial, the value of the

non-controlling

interest is also deemed to be immaterial.

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2019

Stock-Based Compensation Expense Related to Common Stock Options, Restricted Common Stock and Common Stock Warrants

Following is the stock-based compensation expense related to common stock options, common stock, restricted common stock and common stock warrants:


	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Research and development	$	83	$	627	$	170	$	1,161
General and administrative		360		816		685		1,469

Total stock-based compensation expense	$	443	$	1,443	$	855	$	2,630

Weighted Average Assumptions Used to Determine Fair Value of Options Granted

The fair value of all options granted is determined using the Black-Scholes option-pricing model. The following weighted average assumptions were used:


	Six Months Ended June 30,			Six Months Ended June 30,
	2019			2018
Risk-free interest rate		2.68	%		2.47	%
Expected life of the options		6 years			5.7 years
Expected volatility of the underlying stock		104	%		104	%
Expected dividend rate		0	%		0	%

Summary of Stock Option Activity

The following table summarizes the stock option activity in the Company’s equity incentive plans, including

non-plan

grants to Company executives, from December 31, 2018 through June 30, 2019:


	Shares			Weighted Average Exercise Price
Outstanding, December 31, 2018		2,713,979		$	4.67
Granted		530,000			4.72
Exercised		(142,543	)		1.79
Options forfeited/cancelled		(39,098	)		2.09

Outstanding, June 30, 2019		3,062,338		$	4.85

Common Stock Warrants (Tables)

6 Months Ended

Jun. 30, 2019

Text Block [Abstract]

Common Stock Warrant Activity

The following table summarizes the common stock warrant activity from December 31, 2018 through June 30, 2019:


	Shares			Weighted Average Exercise Price
Outstanding, December 31, 2018		10,647,026		$	3.48
Granted		2,622,154			7.00
Exercised		(585,090	)		4.71
Forfeited/cancelled		(143,411	)		3.00

Outstanding, June 30, 2019		12,540,679		$	4.22

Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Basis of Presentation [Line Items]
Unrestricted cash and cash equivalents	$ 52,043	$ 8,253	$ 10,497	$ 3,053
Expected costs of trail and general overhead	$ 100,000

Accrued Expenses and Other (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Jun. 30, 2019
Schedule of Accrued Liabilities [Line Items]
Legal and accounting fees	$ 45	$ 106
Accrued compensation	1,294	715
Lease liability		36
Accrued research and development costs and other	173
Total	$ 1,512	$ 857

Line of Credit - Additional Information (Detail) - USD ($)	1 Months Ended	6 Months Ended
	May 31, 2019	Jun. 30, 2019	Jun. 30, 2018	May 23, 2019	Jan. 31, 2019	Jan. 01, 2019	Dec. 31, 2017	Dec. 19, 2017
Line of Credit Facility [Line Items]
Number of securities called by warrant	500,000	500,000				3,579,642
Warrant value		$ 696,000
Expected life		6 years	5 years 8 months 12 days
Expected Volatility		104.00%	104.00%
Expected dividend		0.00%	0.00%
Risk free interest rate		2.68%	2.47%
Amortization of interest expense		$ 43,000	$ 169,000
Issued of warrant	$ 2,500,000
Director And Shareholder [Member]
Line of Credit Facility [Line Items]
Minority interest							7.00%
Director \| Director And Shareholder [Member]
Line of Credit Facility [Line Items]
Line of credit current		$ 0
Unsecured Line Of Credit \| Director
Line of Credit Facility [Line Items]
Line of credit facility								$ 10,000,000
Short term borrowing interest rate					2.70%
Number of securities called by warrant		1,000,000
Exercise price of warrant		$ 5
Warrant
Line of Credit Facility [Line Items]
Exercise price of warrant				$ 7.00
Expected life		7 years
Expected Volatility		98.00%
Expected dividend		0.00%
Risk free interest rate		2.05%

Stock-Based Compensation - Additional Information (Detail)	3 Months Ended	6 Months Ended
	Jun. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2019 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair values of options granted \| $ / shares	$ 3.83
Unvested option	468,750	468,750
Unrecognized compensation cost \| $	$ 1,301,000	$ 1,301,000
Unrecognized compensation cost, recognition period		1 year 25 days
Number of options granted	530,000	530,000

Stock-Based Compensation Expense Related to Common Stock Options, Restricted Common Stock and Common Stock Warrants (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 443	$ 1,443	$ 855	$ 2,630
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	83	627	170	1,161
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 360	$ 816	$ 685	$ 1,469

Summary of Stock Option Activity (Detail) - $ / shares	3 Months Ended	6 Months Ended
Summary of Stock Option Activity (Detail) - $ / shares	Jun. 30, 2019	Jun. 30, 2019
Shares
Beginning Balance \| shares		2,713,979
Granted \| shares	530,000	530,000
Forfeited/Cancelled \| shares		(39,098)
Exercised \| shares		(142,543)
Ending Balance \| shares	3,062,338	3,062,338
Weighted Average Exercise Price
Beginning Balance \| $ / shares		$ 4.67
Granted \| $ / shares		4.72
Forfeited/Cancelled \| $ / shares		2.09
Exercised \| $ / shares		1.79
Ending Balance \| $ / shares	$ 4.85	$ 4.85

Weighted Average Assumptions Used to Determine Fair Value of Options Granted (Detail)	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	2.68%	2.47%
Expected life of the options	6 years	5 years 8 months 12 days
Expected volatility of the underlying stock	104.00%	104.00%
Expected dividend rate	0.00%	0.00%

Common Stock Warrant Activity (Detail) - Warrant	6 Months Ended
Common Stock Warrant Activity (Detail) - Warrant	Jun. 30, 2019 $ / shares shares
Shares
Outstanding, December 31, 2018 \| shares	10,647,026
Granted \| shares	2,622,154
Exercised \| shares	(585,090)
Forfeited/cancelled \| shares	(143,411)
Outstanding, March 31, 2019 \| shares	12,540,679
Weighted Average Exercise Price
Outstanding, December 31, 2018 \| $ / shares	$ 3.48
Granted \| $ / shares	7.00
Exercised \| $ / shares	4.71
Forfeited/cancelled \| $ / shares	3.00
Outstanding, March 31, 2019 \| $ / shares	$ 4.22

Dilutive Shares Which Could Exist Pursuant to Exercise of Outstanding Stock Instruments and Which were not Included in Calculation (Detail) - shares	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive shares not included in calculation	16,117,619	19,417,730
Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive shares not included in calculation	12,540,679	10,815,336
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive shares not included in calculation	3,062,338	4,294,279
Contingently Issuable Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive shares not included in calculation	514,602	4,308,115

Common Stock - Additional Information (Detail)	1 Months Ended	3 Months Ended			6 Months Ended
Common Stock - Additional Information (Detail)	May 23, 2019 USD ($) yr $ / shares shares	Jun. 30, 2019 shares	Jun. 30, 2018 shares	Mar. 31, 2018 shares	Jun. 30, 2019 USD ($) shares	Jun. 30, 2018 USD ($) shares	May 31, 2019 shares	Jan. 01, 2019 shares	May 19, 2017 USD ($)
Net proceeds from issuance of common stock \| $					$ 49,404,000	$ 14,039,000
Exercise of warrants		500,000			500,000		500,000	3,579,642
Measurement Input, Expected Term [Member]
Fair value assumptions, Measurement Input \| yr	7
Measurement Input, Price Volatility [Member]
Fair value assumptions, Measurement Input	101
Measurement Input, Risk Free Interest Rate [Member]
Fair value assumptions, Measurement Input	2.33
2017 At Market Agreement
Aggregate Offering Price \| $									$ 30,000,000
Commissions as Percentage of Gross Offering Proceeds									3.00%
Shares of common stock issued					395,233
Net proceeds from issuance of common stock \| $					$ 1,865,000
Issuance of common stock					395,233
Other Agreements \| Series A, B and C Preferred Stock
Common stock issued for dividend				74,476
Common Stock [Member]
Shares of common stock issued	10,488,161	10,488,161	618,614		10,883,394	618,614
Net proceeds from issuance of common stock \| $	$ 44,900,000
Issuance of common stock	10,488,161	10,488,161	618,614		10,883,394	618,614
Exercise of warrants	2,622,154
Warrant [Member]
Warrants expiration	May 23, 2026
Price per warrants class \| $ / shares	$ 7.00
Value of warrants \| $	$ 8,200,000
Closing price \| $ / shares	$ 4.01

Preferred Stock Conversion into Common Stock - Additional Information (Detail) $ in Thousands		1 Months Ended	3 Months Ended		6 Months Ended
	Jan. 11, 2019 shares	Jan. 31, 2019 USD ($) shares	Jun. 30, 2019 USD ($) shares	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) shares	Jun. 30, 2018 USD ($)	May 31, 2019 shares	Jan. 01, 2019 shares
Number of shares called by warrants			500,000		500,000		500,000	3,579,642
Recognition of non cash charge related to extension of warrants \| $		$ 6,622	$ 0	$ 0	$ 6,622	$ 0
Warrants Issued		3,579,642
Minimum Expected Life Range [Member] \| Maximum [Member] \| Before Modification of Terms of Warrants [Member]
Derivative Liability		1.33
Minimum Expected Life Range [Member] \| Maximum [Member] \| After Modification of Terms of Warrants [Member]
Derivative Liability		6.33
Minimum Expected Life Range [Member] \| Minimum [Member] \| Before Modification of Terms of Warrants [Member]
Derivative Liability		0.09
Minimum Expected Life Range [Member] \| Minimum [Member] \| After Modification of Terms of Warrants [Member]
Derivative Liability		5.09
Measurement Input, Volatility Rate [Member] \| Before Modification of Terms of Warrants [Member]
Derivative Liability		98
Measurement Input, Volatility Rate [Member] \| After Modification of Terms of Warrants [Member]
Derivative Liability		106
Measurement Input, Risk Free Interest Rate [Member] \| Maximum [Member] \| Before Modification of Terms of Warrants [Member]
Derivative Liability		2.59
Measurement Input, Risk Free Interest Rate [Member] \| Maximum [Member] \| After Modification of Terms of Warrants [Member]
Derivative Liability		2.6
Measurement Input, Risk Free Interest Rate [Member] \| Minimum [Member] \| Before Modification of Terms of Warrants [Member]
Derivative Liability		2.4
Measurement Input, Risk Free Interest Rate [Member] \| Minimum [Member] \| After Modification of Terms of Warrants [Member]
Derivative Liability		2.56
Measurement Input, Dividend Yield Rate [Member] \| Before Modification of Terms of Warrants [Member]
Derivative Liability		0
Measurement Input, Dividend Yield Rate [Member] \| After Modification of Terms of Warrants [Member]
Derivative Liability		0
Common Stock [Member] \| 10X Fund L.P.[Member]
Common stocks issued upon conversion of Preferred Stock	3,789,346
Series B1 B2 and B3 Convertible Preferred Stock [Member] \| 10X Fund L.P.[Member]
Convertible preferred shares	5,508,000

Leases - Maturity of operating lease (Details) $ in Thousands	Jun. 30, 2019 USD ($)
Leases [Abstract]
2019	$ 23
2020	47
2021	48
2022	8
Total	126
Less imputed interest	18
Present value of lease liability	$ 108

Leases Additional Information (Detail) - USD ($)	6 Months Ended
Leases Additional Information (Detail) - USD ($)	Jun. 30, 2019	Jan. 01, 2019
Term of Contract		38 months
Lease Deposits		$ 6,000
Lease liability	$ 36,000
Discount rate	11.04%
Other assets
Right-of-Use Asset	$ 101,000
Accrued And Other Liabilities Current
Lease liability	36,000
Other liabilities
Non current lease liability	72,000
General and administrative
Lease cost	$ 22,000

Galectin Science LLC - Additional Information (Detail) - Galectin Sciences, LLC - USD ($)	1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended	54 Months Ended	57 Months Ended
	Jan. 31, 2014	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2014	Jun. 30, 2019	Jun. 30, 2019
Investments in and Advances to Affiliates [Line Items]
Equity method investment in Galectin Sciences LLC	$ 400,000
Subsequent capital contribution		$ 79,000				$ 1,883,000
Equity Method Investment, Ownership Percentage	50.00%
Loss from equity method investment in Galectin Sciences, LLC				$ 400,000
SBH Sciences, Inc
Investments in and Advances to Affiliates [Line Items]
Subsequent capital contribution					$ 123,000
Ownership Percentage			81.40%
SBH Sciences, Inc \| In Process Research and Development
Investments in and Advances to Affiliates [Line Items]
Estimated fair value of the IPR&D Contributed by SBH	$ 400,000