CASI Pharmaceuticals (CASI) 10-K 30 Mar 21 2020 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2020	Mar. 26, 2021	Jun. 30, 2020
Cover
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2020
Entity File Number	0-20713
Entity Registrant Name	CASI PHARMACEUTICALS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	58-1959440
Entity Address, Address Line One	9620 Medical Center Drive
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Rockville
Entity Address, State or Province	MD
Entity Address, Postal Zip Code	20850
City Area Code	240
Local Phone Number	864-2600
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	CASI
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
ICFR Auditor Attestation Flag	false
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Central Index Key	0000895051
Current Fiscal Year End Date	--12-31
Entity Public Float			$ 183,834,503
Entity Common Stock, Shares Outstanding		139,797,487

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 57,064	$ 53,621
Investment in equity securities, at fair value	9,309	625
Accounts receivable, net of $0 allowance for doubtful accounts	4,645	1,293
Inventories	1,356	4,542
Prepaid expenses and other	1,651	1,420
Assets held-for-sale	0	3,221
Total current assets	74,025	64,722
Property, plant and equipment, net	2,062	985
Intangible assets, net	13,210	13,674
Long-term investments	29,442	14,038
Right of use assets	8,696	8,708
Other assets	299	504
Total assets	127,734	102,631
Current liabilities:
Accounts payable	3,669	5,113
Accrued and other current liabilities	3,015	2,834
Bank borrowings	826	0
Notes payable	466	0
Total current liabilities	7,976	7,947
Deferred income	2,351	0
Other liabilities	13,834	1,019
Total liabilities	24,161	8,966
Commitments and contingencies (Note 21)
Redeemable noncontrolling interest, at redemption value (Note 12)	22,033	20,670
Stockholders' equity:
Preferred stock, $1.00 par value: 5,000,000 shares authorized and 0 shares issued and outstanding	0	0
Common stock, $0.01 par value: 250,000,000 shares authorized at December 31, 2020 and December 31, 2019; 124,023,374 shares and 97,851,243 shares issued at December 31, 2020 and December 31, 2019, respectively; 123,943,829 shares and 97,771,698 shares outstanding at December 31, 2020 and December 31, 2019, respectively	1,240	979
Additional paid-in capital	658,246	606,686
Treasury stock, at cost: 79,545 shares held at December 31, 2020 and December 31, 2019	(8,034)	(8,034)
Accumulated other comprehensive income (loss)	589	(2,728)
Accumulated deficit	(570,501)	(523,908)
Total stockholders' equity	81,540	72,995
Total liabilities, redeemable noncontrolling interest and stockholders' equity	$ 127,734	$ 102,631

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Condensed Consolidated Balance Sheets
Allowance for doubtful accounts	$ 0	$ 0
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 1	$ 1
Preferred Stock, Shares Authorized (in shares)	5,000,000	5,000,000
Preferred Stock, Shares Issued (in shares)	0	0
Preferred Stock, Shares Outstanding (is shares)	0	0
Common Stock, Par Value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized (in shares)	250,000,000	250,000,000
Common Stock, Shares Issued (in shares)	124,023,374	97,851,243
Common Stock, Shares Outstanding (in shares)	123,943,829	97,771,698
Treasury stock, Shares Held (in shares)	79,545	79,545

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenues:
Product sales	$ 15,001,000	$ 4,063,000
Lease income	140,000	68,000
Total revenues	15,141,000	4,131,000
Costs and expenses:
Costs of revenues	9,508,000	3,935,000
Research and development	11,470,000	9,340,000
General and administrative	19,661,000	27,336,000
Selling and marketing	7,815,000	3,103,000
(Gain) Loss on disposal of intangible assets	(1,152,000)	408,000
Impairment of intangible assets	1,537,000	0
Acquired in-process research and development	17,828,000	6,967,000
Total costs and expenses	66,667,000	51,089,000
Loss from operations	(51,526,000)	(46,958,000)
Non-operating income/(expense):
Interest income, net	866,000	1,062,000
Foreign exchange (losses) gains	(1,255,000)	817,000
Change in fair value of investment in equity securities	4,322,000	(288,000)
Other income	82,000	5,000
Net loss	(47,511,000)	(45,362,000)
Less: loss attributable to redeemable noncontrolling interest	(918,000)	(395,000)
Accretion to redeemable noncontrolling interest redemption value	1,694,000	1,065,000
Net loss attributable to CASI Pharmaceuticals, Inc.	$ (48,287,000)	$ (46,032,000)
Net loss per share (basic and diluted)	$ (0.44)	$ (0.48)
Weighted average number of common shares outstanding (basic and diluted)	110,452	95,948
Comprehensive loss:
Net loss	$ (47,511,000)	$ (45,362,000)
Foreign currency translation adjustment	3,904,000	(1,501,000)
Total comprehensive loss	(43,607,000)	(46,863,000)
Less: Comprehensive loss attributable to redeemable noncontrolling interest	(331,000)	(395,000)
Comprehensive loss attributable to common stockholders	$ (43,276,000)	$ (46,468,000)

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Preferred Stock	Common Stock	Additional Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive Loss	Accumulated Deficit	Total
Balance at Dec. 31, 2018	$ 0	$ 954	$ 596,712	$ (8,034)	$ (1,227)	$ (478,941)	$ 109,464
Balance (in shares) at Dec. 31, 2018	0	95,287,268
Issuance of common stock for options and warrants exercised	$ 0	$ 24	4,105	0	0	0	4,129
Issuance of common stock for options and warrants exercised (in shares)	0	2,425,526
Repurchase of stock options to satisfy tax withholding obligations	$ 0	$ 0	(367)	0	0	0	(367)
Issuance of common stock pursuant to financing agreements	$ 0	$ 1	181	0	0	0	182
Issuance of common stock pursuant to financing agreements (in shares)	0	58,904
Stock issuance costs	$ 0	$ 0	(190)	0	0	0	(190)
Stock-based compensation expense, net of forfeitures	0	0	7,310	0	0	0	7,310
Foreign currency translation adjustment	0	0		0	(1,501)	0	(1,501)
Net loss attributable to CASI Pharmaceuticals, Inc.	0	0	(1,065)	0	0	(44,967)	(46,032)
Balance at Dec. 31, 2019	$ 0	$ 979	606,686	(8,034)	(2,728)	(523,908)	72,995
Balance (in shares) at Dec. 31, 2019	0	97,771,698
Issuance of common stock for options and warrants exercised	$ 0	$ 27	3,847	0	0	0	3,874
Issuance of common stock for options and warrants exercised (in shares)	0	2,737,795
Repurchase of stock options to satisfy tax withholding obligations	$ 0	$ 0	(251)	0	0	0	(251)
Issuance of common stock pursuant to financing agreements	$ 0	$ 234	44,865	0	0	0	45,099
Issuance of common stock pursuant to financing agreements (in shares)	0	23,434,336
Stock issuance costs	$ 0	$ 0	(3,028)	0	0	0	(3,028)
Stock-based compensation expense, net of forfeitures	0	0	7,821	0	0	0	7,821
Foreign currency translation adjustment	0	0		0	3,317	0	3,317
Net loss attributable to CASI Pharmaceuticals, Inc.	0	0	(1,694)	0	0	(46,593)	(48,287)
Balance at Dec. 31, 2020	$ 0	$ 1,240	$ 658,246	$ (8,034)	$ 589	$ (570,501)	$ 81,540
Balance (in shares) at Dec. 31, 2020	0	123,943,829

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (47,511,000)	$ (45,362,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization for property, plant and equipment	562,000	603,000
Net loss on disposal of property, plant and equipment	0	2,000
Amortization of intangible assets	1,397,000	1,550,000
Reduction in the carrying amount of the right-of-use assets	1,272,000	424,000
Write down of obsolete inventories	0	152,000
(Gain) Loss on disposal of intangible assets	(1,152,000)	408,000
Impairment of equipment	0	386,000
Impairment of intangible assets	1,537,000	0
Stock-based compensation expense	7,821,000	7,310,000
Acquired in-process research and development	17,828,000	6,967,000
Change in fair value of investment in equity securities	(4,322,000)	288,000
Non-cash interest	0	1,000
Changes in operating assets and liabilities:
Accounts receivable	(3,352,000)	(1,293,000)
Inventories	3,186,000	(4,411,000)
Prepaid expenses and other assets	(184,000)	5,751,000
Accounts payable	(1,540,000)	4,001,000
Payable to related party	0	153,000
Accrued liabilities and other liabilities	(1,393,000)	(173,000)
Deferred income	(35,000)	0
Net cash used in operating activities	(25,886,000)	(23,243,000)
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds from disposal of intangible assets	2,700,000	0
Purchases of property, plant and equipment	(1,499,000)	(427,000)
Purchase of land use rights	0	(6,626,000)
Loan to a related party	(10,033,000)	0
Receipt of repayment of loan from a related party	10,033,000	0
Cash paid to acquire in-process research and development	(17,828,000)	(6,967,000)
Receipt of government grants related to land use right	2,309,000	0
Net cash used in investing activities	(20,719,000)	(28,058,000)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from notes payable	466,000	0
Proceeds from bank borrowings	783,000	0
Repayment of notes payable	0	(1,500,000)
Stock issuance costs	(2,818,000)	(190,000)
Proceeds from sale of common stock and warrants	45,099,000	182,000
Cash contribution from redeemable noncontrolling interest	0	20,000,000
Proceeds from exercise of stock options	3,874,000	854,000
Repurchase of stock options to satisfy tax withholding obligations	(251,000)	(367,000)
Proceeds from exercise of warrants	0	3,275,000
Payment of deferred offering costs	0	(209,000)
Net cash provided by financing activities	47,153,000	22,045,000
Effect of exchange rate change on cash and cash equivalents	2,895,000	(1,328,000)
Net increase (decrease) in cash and cash equivalents	3,443,000	(30,584,000)
Cash and cash equivalents at beginning of year	53,621,000	84,205,000
Cash and cash equivalents at end of year	57,064,000	53,621,000
Supplemental disclosure of cash flow information:
Interest paid	0	30,000
Income taxes paid	0	0
Black Belt Tx Limited
CASH FLOWS FROM INVESTING ACTIVITIES
Cash paid to acquire securities	(83,000)	(2,250,000)
Juventas Cell Therapy Ltd.
CASH FLOWS FROM INVESTING ACTIVITIES
Cash paid to acquire securities	0	(11,788,000)
BioInvent International AB
CASH FLOWS FROM INVESTING ACTIVITIES
Cash paid to acquire securities	$ (6,318,000)	$ 0

DESCRIPTION OF BUSINESS

DESCRIPTION OF BUSINESS	12 Months Ended
	Dec. 31, 2020
DESCRIPTION OF BUSINESS
DESCRIPTION OF BUSINESS	CASI Pharmaceuticals, Inc. Notes to Consolidated Financial Statements December 31, 2020 and 2019 1. DESCRIPTION OF BUSINESS CASI Pharmaceuticals, Inc. (“CASI” or the “Company”) (Nasdaq: CASI) is a U.S. biopharmaceutical company focused on developing and commercializing innovative therapeutics and pharmaceutical products in China, the United States, and throughout the world. The Company is focused on acquiring, developing and commercializing products that augment its hematology oncology therapeutic focus as well as other areas of unmet medical need. The Company is executing its plan to become a biopharmaceutical leader by launching medicines in the greater China market leveraging its China-based regulatory, clinical and commercial competencies and its global drug development expertise. The Company’s operations in China are conducted primarily through two of its subsidiaries: (i) CASI Pharmaceuticals (China) Co., Ltd. (“CASI China”), which is wholly owned and is located in Beijing, China, and (ii) CASI Pharmaceuticals (Wuxi) Co., Ltd. (“CASI Wuxi”), which is located in Wuxi, China. The Company launched in China the Company’s first commercial product, EVOMELA ® ● CNCT19 is an autologous CD19 CAR-T investigative product (CNCT19) being developed by the Company’s partner Juventas Cell Therapy Ltd (“Juventas”) for which the Company has co-commercial and profit-sharing rights. CNCT19 is being developed as a potential treatment for patients with hematological malignancies which express CD19 including, B-cell acute lymphoblastic leukemia (“B-ALL”) and B-cell non-Hodgkin lymphoma (“B-NHL”). China Phase 1 studies have been substantially completed by Juventas, with the Phase 2 B-NHL registration study in China currently enrolling. The Phase 2 B-ALL registration study is expected to start by the end of March 2021. In December 2020, Juventas received a breakthrough therapy designation for CNCT19 in the treatment of adults with relapsed/refractory B-ALL from the Chinese Center for Drug Evaluation, a division of the China National Medical Products Administration. ● BI-1206 is an antibody which has a novel mode-of-action, blocking the inhibitory antibody checkpoint receptor FcγRIIB to unlock anti-cancer immunity in both hematological malignancies and solid tumors for which the Company has exclusive greater China rights BI-1206 is being investigated in a Phase 1/2 trial, in combination with anti-PD1 therapy Keytruda® (pembrolizumab), in solid tumors, and in a Phase 1/2a trial in combination with MabThera® (rituximab) in patients with relapsed/refractory non-Hodgkin lymphoma (NHL). BioInvent International AB, released positive interim results from its Phase 1/2a trial that suggests that novel anti-FcyRIIB antibody BI-1206 restores activity of rituximab in patients with relapsed/refractory non-Hodgkin’s lymphoma. An FDA End of Phase 1 meeting for the NHL development program is planned for the third quarter of 2021. ● CB-5339 is a novel VCP/p97 inhibitor, in mainland China, Taiwan, Hong Kong and Macau. Cleave is a clinical-stage biopharmaceutical company focused on valosin-containing protein (VCP)/p97 as a novel target in protein homeostasis, DNA damage response and other cellular stress pathways for therapeutic use in cancer. CB-5339, an oral second-generation, small molecule VCP/p97 inhibitor, is being evaluated in a Phase 1 clinical trial in patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS), while the National Cancer Institute (NCI) is sponsoring and evaluating CB-5339 in a Phase 1 clinical trial of patients with solid tumors and lymphomas. The Company entered into an exclusive license with Cleave Therapeutics, Inc. (Cleave”) for the development and commercialization of CB-5339 in March 2021. ● CID-103 is a full human IgG1 anti-CD38 monoclonal antibody recognizing a unique epitope that has demonstrated encouraging preclinical efficacy & safety profile compared to other anti-CD38 monoclonal antibodies for which the Company has exclusive global rights. CID-103 is being developed for the treatment of patients with multiple myeloma. The CID-103 Phase 1 study in EU was initiated in March 2021. Other assets in the Company’s pipeline for which the Company has exclusive rights in China are Octreotide Long Acting Injectable (“LAI”), for which the Company plan to begin the China registration study in 2021, and a novel formulation of Thiotepa, for which the Company’s partner plans to begin the China registration study in 2021. Thiotepa is used as a conditioning treatment for certain allogeneic haemopoietic stem cell transplants. Subject to regulatory and marketing approvals, the Company intends to advance and commercialize these established products in China. The Company’s assets include a few FDA-approved ANDAs which the Company is evaluating due to generic drug pricing reforms by the Chinese government and its impact on the pricing and competitiveness of these products. The Company also has greater China rights to ZEVALIN ® ® The Company’s business development strategy is currently focused on acquiring additional targeted drugs and immuno-oncology therapeutics through licensing that will expand its hematology-oncology franchise. In many cases its business development strategy includes direct equity investments in the licensor company. The Company intends for its pipeline to reflect a diversified and risk-balanced set of assets that include (1) late-stage clinical drug candidates in-licensed for China regional rights, (2) proprietary or licensed innovative drug candidates, and (3) select high quality pharmaceuticals that fit its therapeutic focus. The Company uses a market-oriented approach to identify pharmaceutical/biotechnology candidates that the Company believes to have the potential for gaining widespread market acceptance, either globally or in China, and for which development can be accelerated under the Company’s global drug development strategy. Although oncology with a focus on hematological malignancies is its principal clinical and commercial target, The Company is opportunistic about other therapeutic areas that can address unmet medical needs. During the second quarter 2020, the Company completed a plan to change the manufacturing site for EVOMELA to an alternative manufacturer that significantly reduced the cost of revenue since the third quarter of 2020. As part of the long-term strategy to support the Company’s future clinical and commercial manufacturing needs and to manage the Company’s supply chain for certain products, on December 26, 2018, the Company established CASI Pharmaceuticals (Wuxi) Co., Ltd. (“CASI Wuxi”). In November 2019, CASI Wuxi entered into a fifty-year lease agreement for the right to use state-owned land in China for the construction of a manufacturing facility. In April 2020, CASI Wuxi received RMB 15.9 million (equivalent to $2.2 million) from the Jiangsu Province Wuxi Huishan Economic Development Zone as government grant for this development project which was recorded as deferred income in April 2020. On August 27, 2020, CASI Wuxi entered into a Construction Project Contract for RMB 74,588,000 (equivalent to $10,923,000) to complete the phase 1 project of CASI Wuxi's research and development production base (see Note 21). The estimated completion date is October 2023. Certain line items, as disclosed below, in the December 31, 2019 consolidated financial statements have been reclassified to conform to the December 31, 2020 presentation. Loss on disposal of intangible assets in the amount of $0.4 million for the year ended December 31, 2019, which was previously included in research and development, has been separately presented on the consolidated statement of operations and comprehensive loss for the year ended December 31, 2019. Assets held-for-sale in the amount of $3.2 million as of December 31, 2019, which was previously included in intangible assets, and has been reclassified as assets held-for-sale and separately presented on the consolidated balance sheet as of December 31, 2019 (see Note 8). Liquidity Risks and Management’s Plans Since its inception in 1991, the Company has incurred significant losses from operations and, as of December 31, 2020, has incurred an accumulated deficit of $570.5 million. In 2012, with new leadership, the Company shifted its business strategy to China and has since built an infrastructure in China that includes sales and marketing, medical affairs, regulatory and clinical development and in the foreseeable future, manufacturing. In 2014, the Company changed its name to “CASI Pharmaceuticals, Inc.” The majority of the Company’s operations are now located in China. The Company expects to continue to incur operating losses for the foreseeable future due to, among other factors, its continuing clinical and development activities and expansion of the Company’s operations. The Company’s operations in China are conducted primarily through two of the Company’s subsidiaries, CASI Pharmaceuticals (China) Co., Ltd. (“CASI China”) and CASI Pharmaceuticals (Wuxi) Co., Ltd. (“CASI Wuxi”). The Company’s Beijing office is primarily responsible for the Company’s day-to-day operations and the Company’s commercial team of over 80 hematology and oncology sales and marketing specialists based in China. CASI Wuxi is part of the long-term strategy to support the Company’s future clinical and commercial manufacturing needs, to manage the Company’s supply chain for certain products, and to develop a GMP manufacturing facility in China. On July 24, 2020, the Company closed an underwritten public offering of 23 million shares of common stock (the "Offering") and received gross proceeds of $43.7 million before deducting the underwriting discounts and commissions and offering expenses payable by CASI. Certain insiders, including CASI's Chairman and CEO, and CASI's President, purchased shares of common stock in the Offering at the public offering price and on the same terms as the other purchasers in this Offering (see Note 12). The Company is using the net proceeds of this Offering for working capital and general corporate purposes, which include, but are not limited to advancing the Company's product portfolio, acquiring the rights to new product candidates and general and administrative expenses. On November 20, 2020, the Company filed a Form S-3 registration statement with the SEC utilizing a “shelf” registration process. On December 2020, the Form S-3 registration statement was declared effective by the SEC. Pursuant to this shelf registration statement, the Company may sell debt or equity securities in one or more offerings up to a total public offering price of $150 million. As a result of the Company’s failure to timely file a periodic report with the SEC in connection with the adoption of its amended and restated bylaws, absent a waiver of the Form S-3 eligibility requirements, the Company is ineligible to use or file new short form registration statements on Form S-3 until October 1, 2021, assuming the Company continues to timely file the Company’s required Exchange Act reports. In the interim, however, the Company may raise capital pursuant to a registration statement on Form S-1 or on a private placement basis. On March 24, 2021, the Company closed an underwriting agreement (the “Underwriting Agreement”) with Oppenheimer & Co. Inc., as representative of the several underwriters named therein (the “Underwriters”), providing for the offer and sale of 15,853,658 shares of the Company’s common stock (the “Offering”) at a price to the public of $2.05 per share. In addition, the Company granted the Underwriters an option to purchase up to an additional 2,378,048 shares of common stock, which terminates on the earlier of 30 days and the day before the Company files to the Securities and Exchange Commission (“SEC”) the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. The Offering closed on March 26, 2021. The gross proceeds to CASI from the Offering are approximately $32.5 million, excluding the over-allotment option and before deducting the underwriting discounts and commissions and offering expenses payable by CASI. Certain insiders, including CASI’s Chairman and Chief Executive Officer, purchased shares of common stock in the Offering at the public offering price and on the same terms as the other purchasers in this Offering. The Company has agreed to pay the underwriters a commission of 1% of the gross proceeds raised from certain such insiders, and 6% of the gross proceeds raised in the offering from other investors. ​ The Offering is being made by means of a written prospectus supplement and accompanying prospectus forming part of a shelf registration statement on Form S-3 (Registration Statement No. 333-250801), previously filed with the SEC on November 20, 2020, which was declared effective on December 2, 2020. The Company filed a final prospectus supplement, dated March 24, 2021, with the SEC relating to the Offering. Pursuant to the Underwriting Agreement, the Company’s directors and executive officers entered into agreements in substantially the form agreed to by the Underwriters providing for a 90-day “lock-up” period with respect to sales of specified securities, subject to certain exceptions. ​ Taking into consideration the cash and cash equivalents as of December 31, 2020, the Company believes that it has sufficient resources to fund its operations at least one year beyond the date that the consolidated financial statements are issued. As of December 31, 2020, the Company had a balance of cash and cash equivalents of $57.1 million of which $4.5 million was held by CASI China, and $19.5 million was held by CASI Wuxi. The Company intends to continue to exercise tight controls over operating expenditures and will continue to pursue opportunities, as required, to raise additional capital and will also actively pursue non- or less-dilutive capital raising arrangements or opportunities, as required, to raise additional capital and will also actively pursue non- or less-dilutive capital raising arrangements. Risks and Uncertainties The Company's business has been and may continue to be adversely affected by the COVID-19 pandemic. In March 2020, the World Health Organization characterized the outbreak of COVID-19 as a pandemic. Due to the evolving and highly uncertain nature of this event, the Company cannot predict at this time the full extent to which the COVID-19 pandemic will adversely impact its business, results and financial condition. The impact will depend on many factors that are not known at this time. These include, among others, the extent of harm to public health, the continued disruption to operations, and the impact of the global business and economic environment on liquidity and the availability of capital. The Company has experienced operational interruptions as a result of COVID-19, including the temporary disruption of operations in China due to a Chinese government mandated quarantine protocol, including mandatory business closures, social distancing measures, and various travel restrictions. Although the Company's operations in China are beginning to normalize, there can be no assurance that such operations will continue to do so or that there will not be a renewed outbreak of COVID-19 due to new variants of the virus or other significant contagious diseases in China or elsewhere. To the extent that such events occur, demand for the Company's products may decline, and the Chinese government or other governments may impose additional restrictions resulting in further shutdowns, further work restrictions, and the disruption of the Company’s supply and distribution channels. The COVID-19 pandemic has adversely affected, and may continue to adversely affect, the economies and financial markets of many countries, which may result in a period of regional, national, and global economic slowdown or regional, national, or global recessions that could affect the Company's ability to continue to commercialize and expand distribution of EVOMELA (Melphalan For Injection) or other drugs in the Company’s existing product pipeline. The effectiveness of the Company's sales teams may be negatively impacted by the lack of travel and their reduced ability to engage with decision-makers. In the first quarter of 2020, during which the peak of the pandemic occurred in China, the Company experienced some disruptions to EVOMELA marketing and sales activities due to travel restrictions and the prioritization of hospitals and physicians to attend to patients with COVID-19 infection. During the remainder of 2020, operations have returned to expected levels; however, there can be no assurance that such restrictions will not be imposed again. In addition, economic and other uncertainties may adversely affect other parties' willingness to negotiate and execute product licenses and thus hamper the Company's ability to in-license clinical-stage and late-stage drug candidates in China or elsewhere. The Company currently relies on a single source for its supply of EVOMELA. Due to COVID-19, the Company experienced a disruption to its supply chain for EVOMELA. That disruption, along with a change in 2020 in the manufacturer of EVOMELA, contributed to a decrease in the Company's revenue for the second quarter of 2020. The Company has returned to expected levels of sales as indicated by the increase in sales in the second half of 2020. If suppliers refuse or are unable to provide products for any reason (including the occurrence of an event like the COVID-19 pandemic that makes delivery impractical), the Company would be required to negotiate an agreement with a substitute supplier, which would likely interrupt the manufacturing of EVOMELA, cause delays and increase costs. Clinical trials, whether planned or ongoing, may be affected by the COVID-19 pandemic. The Company's partner, Juventas, experienced some delay in the conduct of the CNCT19 clinical trials due to the COVID-19 pandemic. The COVID-19 pandemic has also impacted the Company's targeted start time of CID-103 trial due to the lock-down of many medical facilities in Europe. Study procedures (particularly any procedures that may be deemed non-essential), site initiation, participant recruitment and enrollment, participant dosing, shipment of the Company's product candidates, distribution of clinical trial materials, study monitoring, site inspections and data analysis may be paused or delayed due to changes in hospital or research institution policies, federal, state or local regulations, prioritization of hospital and other medical resources toward COVID-19 efforts, or other reasons related to the pandemic. In addition, there could be a potential effect of COVID-19 on the operations of the health regulatory authorities, which could result in delays of reviews and approvals, including with respect to the Company's product candidates. Any prolongation or de-prioritization of the Company's clinical trials or delay in regulatory review resulting from such disruptions could materially affect the development and study of the Company's product candidates. ​ License and Distribution Agreements China Resources Guokang Pharmaceuticals Co., Ltd The Company has product rights and perpetual exclusive licenses from Acrotech Biopharma L.L.C. (“Acrotech”) to develop and commercialize its commercial product EVOMELA® in the greater China region (which includes China, Taiwan, Hong Kong and Macau). On December 3, 2018, the Company received NMPA’s approval for importation, marketing and sales in China, and in August 2019 the Company launched EVOMELA in China. The NMPA required post-marketing study is ongoing and is actively recruiting. In March 2019, the Company entered into a three-year exclusive distribution agreement with China Resources Guokang Pharmaceuticals Co., Ltd (“CRGK”) to appoint CRGK on an exclusive basis as its distributor to distribute EVOMELA in the territory of the People’s Republic of China (excluding Hong Kong, Taiwan and Macau), subject to certain terms and conditions. The Company’s internal marketing and sales team will continue to be responsible for commercial activities, including, for example, direct interaction with Key Opinion Leaders (KOL), physicians, hospital centers and the generating of sales. Commercial sales of EVOMELA were launched in August 2019. For the year ended December 31, 2020 and 2019, the Company recognized $15.0 million and $4.1 million, respectively, of revenues from sales of EVOMELA under this arrangement. Juventas Cell Therapy Ltd In June 2019, the Company entered into a license agreement for worldwide license to commercialize an autologous anti-CD19 T-cell therapy product (CNCT19) from Juventas Cell Therapy Ltd (“Juventas”) (the “Juventas license agreement”). Juventas is a China- based company engaged in cell therapy. The terms of the agreement include RMB 70 million ($10 million) of milestone payments upon the registration of Phase II clinical trial of CNCT19 and sales royalty payments. The milestone became probable to be met during the quarter ended September 30, 2020. As a result, the Company paid the milestone payment of RMB 70 million to Juventas in September 2020 (see Note 3), which was expensed as acquired in-process research and development in the accompanying consolidated statement of operations and comprehensive income for the year ended December 31, 2020. In September 2020, Juventas and its shareholders (including CASI Biopharmaceuticals) agreed to certain terms and conditions required by a new third-party investor to facilitate the Series B financing of Juventas, pursuant to which the Company agreed to amend and supplement the original licensing agreement (the "Supplementary Agreement") by agreeing to pay Juventas certain percentage of profits generated from commercial sales of CNCT19. The Supplementary Agreement also specifies a minimum annual target net profit to be distributed to Juventas and certain other terms and obligations. In return, the Company obtained additional equity interests in Juventas (see Note 3). Under the Supplementary Agreement, Juventas and the Company will jointly market CNCT19, including, but not limited to, establishing medical teams, developing medical strategies, conducting post-marketing clinical studies, establishing Standardized Cell Therapy Centers, establishing and training providers with respect to cell therapy, testing for cell therapy, and monitoring quality controls (cell collection and transfusion, etc.), and patient management (adverse reactions treatment, patients’ follow-up visits, and establishment of a database). The Company also will reimburse Juventas for a portion of Juventas’ marketing expenses as reviewed and approved by a joint commercial committee to be constituted. The Company will continue to be responsible for recruiting and establishing a sales team to commercialize CNCT19. In November 2020, Juventas Cell Therapy Ltd completed the Series B financing. BioInvent International AB In October 2020, the Company entered into an exclusive licensing agreement with BioInvent International AB (“BioInvent”) for the development and commercialization of novel anti-FcγRIIB antibody, BI-1206, in mainland China, Taiwan, Hong Kong and Macau. BioInvent is a biotechnology company focused on the discovery and development of first-in-class immune-modulatory antibodies for cancer immunotherapy. Under the terms of the agreement, BioInvent and CASI will develop BI-1206 in both hematological malignancies and solid tumors, with CASI responsible for commercialization in China and associated markets. CASI made a $5.9 million upfront payment in November 2020 to BioInvent and will pay up to $83 million in development and commercial milestone payments plus tiered royalties in the high-single to mid-double-digit range on net sales of BI-1206. Because BI-1206 underlying the acquired rights has not reached technological feasibility and has no alternative uses, the Company expensed $5.9 million as acquired in-process research and development in the accompanying consolidated statement of operations and comprehensive loss for the year ended December 31, 2020. Black Belt Therapeutics Limited In April 2019, the Company entered into a license agreement with Black Belt Therapeutics Limited (“Black Belt”) for exclusive worldwide rights to CID-103, an investigational anti-CD38 monoclonal antibody (Mab) (formerly known as TSK011010). The CID-103 Phase 1 study is scheduled to begin in EU in March 2021. The Company expects that its clinical materials and commercial inventory will be supplied by one or more contract manufacturers with whom the Company is in current discussions. Under the terms of the agreement, CASI obtained global rights to CID-103 for an upfront payment of 5 million euros ($5.7 million) as well as certain milestone and royalty payments. Because CID-103 underlying the acquired rights has not reached technological feasibility and has no alternative uses, the Company expensed 5 million euros as acquired in-process research and development in the accompanying consolidated statement of operations and comprehensive loss for the year ended December 31, 2019. Cleave Therapeutics, Inc. In March 2021, the Company entered into an exclusive license with Cleave Therapeutics, Inc. (“Cleave”) for the development and commercialization of CB-5339, an oral novel VCP/p97 inhibitor, in both hematological malignancies and solid tumors, in Mainland China, Hong Kong, Macau and Taiwan. Cleave is a clinical-stage biopharmaceutical company focused on valosin-containing protein (VCP)/p97 as a novel target in protein homeostasis, DNA damage response and other cellular stress pathways for therapeutic use in cancer. CB-5339 is being evaluated in a Phase 1 clinical trial in patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS), while the National Cancer Institute (NCI) is sponsoring and evaluating CB-5339 in a Phase 1 clinical trial of patients with solid tumors and lymphomas. Pharmathen Global BV On October 29, 2019, the Company entered into an exclusive distribution agreement with Pharmathen Global BV ("Pharmathen") for the development and distribution of octreotide long acting injectable (Octreotide LAI) microsphere in China. Octreotide LAI formulations, which are approved in various European countries, are considered a standard of care for the treatment of acromegaly and the control of symptoms associated with certain neuroendocrine tumors. Subject to regulatory and marketing approvals, the Company intends to advance and commercialize these established products in China. The terms of the agreement include an upfront payment of 1 million euros which was paid by the Company in 2019, and up to 2 million euros of additional milestone payments. During the year ended December 31, 2020, milestones were achieved related to Pharmathen's approval of Octreotide in the UK, which triggered a 1 million euros payment to Pharmathen, and related to the first submission to the National Medical Products Administration in China, triggering a 500,000 euros payment to Pharmathen. The 1.5 million euros ($1.7 million) was expensed as acquired in-process research and development in the accompanying consolidated statement of operations and comprehensive income for the year ended December 31, 2020. CASI is responsible for the development, import drug registration, product approval and commercialization in China. CASI has a 10-year non-royalty exclusive distribution period after the product launch at agreed supply costs for the first three years. Riemser Pharma GmbH In August 2019, the Company entered into an distribution agreement in China with Riemser Pharma GmbH (“Riemser”) to a novel formulation of thiotepa, a chemotherapeutic agent, which has multiple indications including use as a conditioning treatment for use prior to allogenic hematopoietic stem cell transplantation. Thiotepa has a long history of established use in the hematology/oncology setting. Pursuant to the distribution agreement, CASI obtained the exclusive distribution right of the products in China, and Riemser will be responsible for manufacturing and supplying CASI with clinical materials and commercial inventory. Subject to regulatory and marketing approvals, the Company intends to advance and commercialize these established products in China. ​

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2020
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The Company's significant accounting estimates relate to recoverability of operating lease right-of-use assets, intangible assets and long-term investments, net realizable value and obsolescence allowance for inventory, deferred tax assets and valuation allowance, allowance for doubtful accounts, stock-based arrangements and fair value of investments in equity securities in Juventas. Management bases its estimates on historical experience and on various other assumptions that it believes are reasonable under the circumstances. Actual results may differ from those estimates, and such differences may be material to the consolidated financial statements. Consolidation The accompanying consolidated financial statements include the accounts of the Company and its subsidiaries, in which CASI, directly or indirectly, has a controlling financial interest. These subsidiaries include Miikana Therapeutics, Inc. ("Miikana"), CASI China, CASI Wuxi and CASI Biopharmaceuticals. CASI China is a non-stock Chinese entity with 100% of its interest owned by CASI. CASI China received approval for a business license from the Beijing Industry and Commercial Administration in August 2012 and has operating facilities in Beijing. CASI Wuxi was established on December 26, 2018 in China to develop a manufacturing facility in China. CASI Biopharmaceuticals is a wholly owned subsidiary of CASI Wuxi and was established in April 2019. The Company controls CASI Wuxi through 80% voting rights. Accordingly, the financial statements of CASI Wuxi have been consolidated in the Company's consolidated financial statements since its inception. All inter-company balances and transactions have been eliminated in consolidation. The Company currently operates in one operating segment, which is the development of innovative therapeutics addressing cancer and other unmet medical needs for the global market. Foreign Currency Translation and Transactions The accompanying consolidated financial statements of the Company are reported in US dollars. The financial position and results of operations of the Company’s subsidiaries in the PRC are measured using the Renminbi (RMB), which is the local and functional currency of these entities. Assets and liabilities of the Company’s PRC subsidiaries are translated into US$ using the exchange rates in effect at the consolidated balance sheet date. The revenues and expenses of these entities are translated into US$ at the weighted average exchange rates for the period. The resulting translation gains (losses) are recorded in accumulated other comprehensive income (loss) as a component of shareholders’ equity. Transactions denominated in foreign currencies are remeasured into the functional currency at the exchange rates prevailing on the transaction dates. Foreign currency denominated financial assets and liabilities are remeasured at the exchange rates prevailing at the balance sheet date. Net gains or losses resulting from foreign currency denominated transactions are recorded in foreign exchange gain (losses) in the consolidated statements of operations. Revenue Recognition Product sales recognized in the consolidated statements of operations are considered revenue from contracts with customers and, accordingly, the Company recognizes revenue using the following steps: ● Identification of the contract, or contracts, with a customer; ● Identification of the performance obligations in the contract; ● Determination of the transaction price, including the identification and estimation of variable consideration; ● Allocation of the transaction price to the performance obligations in the contract; and ● Recognition of revenue when the Company satisfies a performance obligation. The Company recognizes revenue on sales of EVOMELA when the control of the product is transferred to the distributor, which occurs upon delivery of the product to the carrier appointed by the distributor, in an amount that reflects the consideration to which the Company expects to be entitled to in exchange for the product, excluding amounts collected on behalf of third parties (e.g. value-added taxes). Payment terms for these sales are due within 90 days. The arrangement does not include any variable consideration. The costs of assurance type warranties that provide the customer the right to exchange purchased product that does meet appropriate quality standards are recognized when they are probable and are reasonably estimable. There was no product exchange during the years ended December 31, 2020 and 2019. As of December 31, 2020 and 2019, the Company did not incur, and therefore did not defer, any material costs to obtain or fulfill contracts. The Company did not have any contract assets or contract liabilities as of December 31, 2020 and 2019. Concentrations of Risk Cash Concentration Risk The Company maintains its U.S. and RMB cash in bank deposit accounts, which, at times, may exceed regulated insured limits. The Company believes it is not exposed to significant credit risk on cash and cash equivalents. Vendor Concentration Risk The Company has a sole supplier for its EVOMELA product. Through the second quarter of 2020, it was sourced solely from Spectrum Pharmaceuticals, Inc. (“Spectrum”) and its suppliers. Starting with the third quarter of 2020, and all future needs will be sourced from Acrotech and its suppliers. The Company’s ability to select other providers of EVOMELA is limited by FDA regulations. Accounts Receivable and Credit Concentration CRGK is the sole customer of the Company's EVOMELA product sales in China. All consolidated revenues for the year ended December 31, 2020 and 2019 were generated from sales to CRGK in China, and all the Company's accounts receivable balance as of December 31, 2020 and 2019 were due from CRGK. Accounts receivable consist of CRGK receivables of $4.6 million and $1.3 million as of December 31, 2020 and 2019, respectively. The Company extends credit to CRGK on an unsecured basis and maintains an allowance for doubtful accounts for estimated losses inherent in its accounts receivable. In establishing the required allowance, management considers the historical losses, customer’s financial condition, the amount of accounts receivables in dispute, the accounts receivables aging and the customer’s payment pattern. The Company determined that no allowance for doubtful accounts were necessary as of December 31, 2020 and 2019. The balance of accounts receivable as of December 31, 2020 has been subsequently collected. Fair Value of Financial Instruments The majority of the Company’s financial instruments (consisting principally of cash and cash equivalents, accounts receivable, prepaid expenses, accounts payable, accrued liabilities, bank borrowings, and notes payable) are carried at cost which approximates their fair values due to the short-term nature of the instruments. The Company’s investment in equity securities is carried at fair value, and its investment in convertible loan-AFS are carried at fair value (see Note 3). The Company also had a note payable which was paid off during the year ended December 31, 2019 (see Note 11). See Note 18 for additional fair value disclosures. Cash and Cash Equivalents Cash and cash equivalents include cash and highly liquid investments with original maturities of less than 90 days that are readily convertible to known amounts of cash. Inventories Inventories consist of EVOMELA finished goods and raw materials to be used in production of ANDAs and are stated at the lower of cost or net realizable value. Cost is determined using a first-in, first-out method. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. Adjustments are recorded to write down the carrying amount of any obsolete and excess inventory to its estimated net realizable value based on historical and forecasted demand. Property, Plant and Equipment Property, plant and equipment are stated at cost, less accumulated depreciation and impairment, if any. Costs incurred in the construction of property, plant and equipment, including down payments and progress payments, are initially capitalized as construction-in-progress and transferred into their respective asset categories when the assets are ready for their intended use, at which time depreciation commences. Furniture and equipment are depreciated over their estimated useful lives of 3 Costs of Revenues Costs of revenues consist primarily of the cost of inventories of EVOMELA and sales-based royalties related to the sale of EVOMELA. Investments Investment in equity securities with readily determinable fair value are measured at fair values, and any changes in fair value are recognized in earnings. Where the fair value of an investment in equity securities is not readily determinable, the Company recognizes such investment in long-term investments, and uses the measurement alternative of cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. For equity investments measured at fair value with changes in fair value recorded in earnings, the Company does not assess whether those securities are impaired. For equity investments without readily determinable fair value, at each reporting period, the Company makes a qualitative assessment considering impairment indicators to evaluate whether the investment is impaired. Impairment indicators that the Company considers include, but are not limited to, (i) the deterioration of earnings performance, credit rating, asset quality, or business prospects of the investee, (ii) a significant adverse change in the regulatory, economic, or technological environment of the investee, (iii) a significant adverse change in the general market condition of either the geographic area or the industry in which the investee operates. If a qualitative assessment indicates that the investment is impaired, the Company has to estimate the investment’s fair value and if the fair value is less than the investment’s carrying value, the Company recognizes an impairment loss in non-operating expenses equal to the difference between the carrying value and fair value. Dividend income is recognized in other income when earned. Leases The Company adopted Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) Prior to the adoption of ASC 842, operating leases were not recognized on the balance sheet of the Company, instead rent expenses with fixed escalating payments and/or rent holidays were recognized on a straight-line basis over the lease term. Upon adoption of ASC 842, ROU assets and lease liabilities are recognized upon lease commencement for operating leases based on the present value of lease payments over the lease term. As the rate implicit in the lease cannot be readily determined, the Company uses incremental borrowing rate at the lease commencement date in determining the imputed interest and present value of lease payments. The incremental borrowing rate was determined based on the rate of interest that the Company would have to borrow an amount equal to the lease payments on a collateralized basis over a similar term. The incremental borrowing rate is primarily influenced by the risk-free interest rate of China and the US, the Company’s credit rating and lease term, and is updated for measurement of new lease liabilities. For operating leases, the Company recognizes a single lease cost on a straight-line basis over the remaining lease term. The Company has elected not to recognize ROU assets or lease liabilities for leases with an initial term of 12 months or less; the Company recognizes lease expense for these leases on a straight-line basis over the lease term. In addition, the Company has elected not to separate non-lease components (e.g., common area maintenance fees) from the lease components. Land use rights acquired are assessed in accordance with ASC 842 and recognized in right-of-use assets if they meet the definition of lease. Impairment of Long-Lived Assets Long-lived assets, including property, plant and equipment, operating lease right-of-use (“ROU”) assets and intangible assets subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Such events and circumstances include the use of the asset or asset group in current research and development projects and any potential alternative uses of the asset or asset group. If circumstances require a long-lived asset or asset group be tested for possible impairment, the Company first compares undiscounted cash flows expected to be generated by that asset or asset group to its carrying value. If the carrying value of the long-lived asset or asset group is not recoverable on an undiscounted cash flow basis, an impairment is recognized to the extent that the carrying value exceeds its fair value. Fair value is determined through various valuation techniques including discounted cash flow models, quoted market values and third-party independent appraisals, as considered necessary. Impairment charges related to property, plant and equipment were $0 and $386,000 for the years ended in December 31, 2020 and 2019, respectively. Impairment charges related to intangibles were $1.5 million and $0 for the years ended in December 31, 2020 and 2019, respectively. Research and Development Expenses Research and development expenses consist primarily of compensation and other expenses related to research and development personnel, research collaborations, costs associated with pre-clinical testing and clinical trials of the Company’s product candidates, including the costs of manufacturing drug substance and drug product, regulatory maintenance costs, and facilities expenses, along with the amortization of acquired ANDAs. Research and development costs are expensed as incurred. Stock-Based Compensation The Company records compensation expense associated with service and performance-based stock options in accordance with provisions of authoritative guidance. The estimated fair value of service-based awards is determined using option pricing models that use unobservable inputs and is generally recognized on a straight-line basis over the requisite service period and based on the proportionate amount of the requisite service period that has been rendered during each reporting period. The estimated fair value of performance-based awards is measured on the grant date and is recognized when it is determined that it is probable that the performance condition will be achieved. Government Grants Government grants are recognized when there is reasonable assurance that the Company will comply with required conditions and the grants will be received. Government grants related to assets are presented as deferred income that is recognized on a systematic basis over the useful life of the asset. Income Taxes Income tax expense is recognized using the asset and liability method. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities and operating loss and tax credit carryforwards as measured by the enacted tax rates that will be in effect when these differences reverse. A valuation allowance is provided to reduce the amount of deferred income tax assets if it is considered more likely than not that some portion or all of the deferred income tax assets will not be realized. The Company recognizes in its consolidated financial statements the impact of a tax position if a tax return position or future tax position is “more likely-than-not” to be sustained upon examination, based on the technical merits of the position. Tax positions that meet the “more-likely-than-not” recognition threshold are measured at the largest amount of tax benefit that has a greater than fifty percent likelihood of being realized upon settlement. The Company recognizes interest and penalties related to uncertain tax positions, if any, in income tax expense. Net Loss Per Share Net loss per share (basic and diluted) was computed by dividing net loss attributable to common shareholders by the weighted average number of shares of common stock outstanding. As of December 31, 2020, and 2019, outstanding stock options totaling 16,746,238 and 18,268,372, respectively, and outstanding warrants totaling 8,271,709 and 9,843,720, respectively, were anti-dilutive, and therefore, were not included in the computation of weighted average shares used in computing diluted loss per share. New Accounting Pronouncements Recently Adopted Pronouncements Effective January 1, 2019, the Company adopted Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2016-02, Leases (“Topic 842”). The guidance amends the accounting requirements for leases and requires lessees to recognize assets and liabilities related to long-term leases on the balance sheets and expands disclosure requirements regarding leasing arrangements. The Company adopted this guidance on a modified retrospective basis and used the following practical expedients: ● The Company did not reassess if any expired or existing contracts are or contain leases; ● The Company did not reassess the classification of any expired or existing leases. Upon adoption of the new guidance on January 1, 2019, the Company recorded right of use assets of $3.0 million and recognized lease liabilities of $3.2 million. There was no cumulative effect impact to accumulated deficit as of January 1, 2019. No adjustments were made to prior comparative periods. In August 2018, the FASB issued ASU 2018-15, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The new guidance requires a customer in a cloud computing arrangement (i.e., hosting arrangement) that is a service contract to follow the internal-use software guidance in ASC 350-40 to determine which implementation costs to capitalize as assets or expense as incurred. Capitalized implementation costs related to a hosting arrangement that is a service contract will be amortized over the term of the hosting arrangement, beginning when the module or component of the hosting arrangement is ready for its intended use. The update is effective for calendar-year public business entities in 2020. For all other calendar-year entities, it is effective for annual periods beginning in 2021 and interim periods in 2022. Early adoption is permitted. The Company early adopted this guidance effective January 1, 2019. The net impact to the financial statements was $140,000 of capitalized cost. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement. ASU 2018-13 eliminates, adds and modifies certain disclosure requirements for fair value measurements. The amendments applicable to the disclosures of changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial year of adoption. This ASU is effective for all entities for fiscal years beginning after December 15, 2019, including interim periods therein. All other amendments should be applied retrospectively to all periods presented upon their effective date. Early adoption is permitted, and an entity is also permitted to early adopt any removed or modified disclosures and delay adoption of the additional disclosures until their effective date. The Company adopted this guidance effective January 1, 2020. The adoption of this new accounting standard did not have a significant impact on the Company's consolidated financial statements. Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments — Credit Losses (Topic 326) (“ASU 2016-13”) and subsequent amendments to the initial guidance including ASU No. 2018-19, ASU No. 2019-04, and ASU No. 2019-05 (collectively, “Topic 326”). Topic 326 requires entities to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. This replaces the existing incurred loss model and is applicable to the measurement of credit losses on financial assets measured at amortized cost. This standard is effective for public business entities, excluding entities eligible to be smaller reporting companies for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. For all other entities, this standard is effective for annual and interim periods beginning after December 15, 2022 and early adoption is permitted for annual and interim periods beginning after December 15, 2018. As a smaller reporting company, the Company expects to adopt this standard in fiscal year 2023. The Company is currently assessing the impact that the adoption of this ASU will have on the consolidated financial statements. There are no other recently issued accounting pronouncements that are expected to have a material effect on the Company’s financial position, results of operations or cash flows.

INVESTMENT IN EQUITY SECURITIES

INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS	12 Months Ended
	Dec. 31, 2020
INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS
INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS	3. INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS Investment in equity securities, at fair value MaxCyte Inc. The Company has an equity investment in the common stock of MaxCyte, a publicly traded company. The Company’s investment in this equity security is carried at its fair value, with changes in fair value reported in the statement of operations each reporting period. The fair value of this security was measured using its quoted market price, a Level 1 input, and was $2.7 million as of December 31, 2020 and $0.6 million on December 31, 2019 (see Note 18). BioInvent International AB In October 2020, in conjunction with its license agreement entered into with BioInvent (see Note 1), a publicly traded company, CASI made a $6.3 million investment (equivalent to SEK 53.8 million) to acquire 1.2 million new shares (after 25:1 reverse stock split) of BioInvent, and 14,700,000 warrants, each warrant with a right to subscribe for 0.04 shares (after 25:1 reverse stock split) in BioInvent within a period of five years. The investments in the ordinary shares and warrants of BioInvent are carried at fair value, with changes in fair value reported in the statement of operations each reporting period. The fair value of the ordinary shares was measured using its quoted market price, a Level 1 input, and was $6.6 million as of December 31, 2020 (see Note 18). The fair value of the warrants was measured using observable market-based inputs other than quoted prices in active markets for identical assets or liabilities, level 2 inputs. The Company uses the Black-Scholes-Merton valuation model to estimate the fair value of warrants. The fair value of the warrants was $841,000 as of December 31, 2020 (see Note 18), with assumptions including an expected life of 4.91 years, an assumed volatility of 47.63%, and a risk-free interest rate of 0.36%. The following table summarizes the Company’s investments in equity securities at Fair Value as of December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ ​ (In thousands) ​ ​ ​ ​ ​ ​ unrealized ​ Aggregate fair Description Classification Cost gains value MaxCyte - equity interest Investment ​ $ — ​ $ 2,729 ​ $ 2,729 BioInvent - equity interest Investment ​ $ 5,661 ​ $ 919 ​ $ 6,580 ​ Unrealized gain (losses) on the Company’s equity investment for the year ended December 31, 2020 and 2019 were $3.2 million and ($288,000), respectively, and are recognized as change in fair value of investment in equity securities in the accompanying consolidated statements of operations and comprehensive loss. Long-term investments Long-term investments consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (In thousands) 2020 2019 Available-for-sale debt securities: ​ ​ Black Belt Tx Limited - convertible loan ​ $ 83 ​ $ — Securities measured at fair value: ​ ​ ​ ​ ​ ​ BioInvent International AB - warrants ​ ​ 840 ​ ​ — Equity securities without readily determinable fair value: ​ ​ Black Belt Tx Limited - equity interest ​ 2,250 ​ 2,250 Juventas Cell Therapy Ltd - equity interest ​ 26,059 ​ 11,355 Juventas Cell Therapy Ltd - put option ​ 210 ​ 433 Total ​ $ 29,442 ​ $ 14,038 ​ Black Belt Tx Limited In April 2019, in conjunction with its license agreement entered into with Black Belt (see Note 1), the Company made a 2 million euros ($2,249,600) equity investment in the ordinary shares of a newly established, privately held UK Company, Black Belt Tx Ltd ("Black Belt Tx"), representing a 14.1% equity interest with the right to appoint a non-voting board observer. As the Company does not have significant influence over operating and financial policies of Black Belt Tx, and the equity interests do not have readily determinable fair value, the investment in Black Belt Tx is stated at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment. The Company did not record any adjustments or impairments during the year ended December 31, 2020 and 2019 related to this investment. In July 2020, the Company entered into a three-year convertible loan agreement with Black Belt Tx (the "Black Belt Tx Loan") in the amount of 211,800 euros ($250,000) with a non-compounding annual interest rate of 6% payable at maturity. The principal balance is also due at maturity. The proceeds will support and advance Black Belt Tx's programs and general operations. The loan principal will be disbursed in three equal installments of 70,600 euros ($83,000). The first tranche was disbursed upon execution of the loan agreement in August 2020. The second tranche was disbursed in February 2021. In the first quarter of 2021, Black Belt Tx reached certain operational circumstances as stipulated in the loan agreement, and Black Belt Tx’s Board of Directors met in February 2021 to approve disbursement of the second tranche. The third tranche will be disbursed in the event Black Belt Tx reaches again certain operational circumstances as stipulated in the loan agreement and with Black Belt Tx's Board of Directors' approval. In the event that Black Belt Tx, on or prior to the maturity date, completes an equity financing round of at least 5,000,000 euros ($5.9 million), then the outstanding principal amount shall be automatically converted into such shares at 80% of the price per share issued divided by a compensating factor based on the number of years that the Black Belt Tx Loan has been outstanding. The investment in convertible loan is accounted for as investment in debt securities as available-for-sale instrument. Juventas Cell Therapy Ltd In June 2019, in conjunction with its license agreement entered into with Juventas (see Note 1), the Company, through CASI Biopharmaceuticals, a wholly-owned subsidiary of CASI Wuxi, made an RMB 80 million ($11,788,000) investment in Juventas, a privately held, China-based company, in Juventas' Series A plus equity, which represented a 16.327% equity interest on a fully diluted basis, and the right to appoint a non-voting board observer. The Company was entitled with substantive liquidation preference over the founding shareholder of Juventas. In addition, the Juventas' founding shareholder provided a put option to the Company pursuant to which the Company can put the equity investment to the founding shareholder at a fixed return of 8% per annum upon occurrence of certain events. The investment in the equity interests of the Juventas and the investment in put option to the founding shareholder were accounted for as investments in equity securities using the measurement alternative at its cost, minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer, as the fair value of the equity securities of Juventas is not readily determinable. The consideration of RMB 80 million ($11,788,000) was allocated into investment in equity interests and investment in put option based on their relative fair value on the transaction date. In September 2020, in conjunction with the Supplementary Agreement entered into with Juventas (see Note 1), the Company obtained additional Series A plus equity interest in Juventas with substantive liquidation preference over Juventas' founding shareholder, resulting in the Company's equity ownership increasing to 16.45% (post-Juventas Series B financing) on a fully diluted basis. CASI Biopharmaceuticals is also entitled to appoint a director to Juventas’ board of directors. Juventas' founding shareholder also provided a put option to the Company pursuant to which the Company can put the additional equity investment to the founding shareholder at RMB 70 million plus a fixed return of 8% per annum upon occurrence of certain events. The transaction closed on September 29, 2020. The fair value of the Company's additional equity interest in Juventas and the new put option was RMB 83.7 million ($12.3 million) and RMB 0.4 million ($64,000) on September 29, 2020, respectively, which was estimated using significant estimates and assumptions, including multiples of selected comparable companies in applying the market approach model. Since the equity interest with substantive liquidation preference is not in-substance common stock, the investment in the additional equity interests of Juventas was accounted for as an investment in equity securities at transaction date fair value with a corresponding credit to Other Liabilities. The profit-sharing liability represents the Company's obligation to pay an increased share of future profits pursuant to the Supplementary Agreement (see Note 1) which was conveyed by the Company in exchange for the additional equity interests in Juventas. The Company views this as a payment from a vendor that should reduce cost of revenues over the period of royalty payments. The long-term liability will be derecognized as payments are made on a systematic and rational basis representing the pattern in which the Company expects to settle the profit-sharing payment during the commercialization period of CNCT19. The investments are measured using the measurement alternative at its cost, minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer, as the fair value of the equity securities of Juventas is not readily determinable. In addition, the changes in the fair value of the original investment in equity interests and put option in the amount of $1,116,000 resulting from the observable price in this transaction was recognized during the year ended December 31, 2020. In June 2020, the Company entered into a one-year loan agreement with Juventas in the amount of RMB 30,000,000 ($4,243,000) with an annual interest rate of 20%. In August 2020, the Company entered into another one-year loan with Juventas in the amount of RMB 40 million ($5,790,000) for one year with an annual interest rate of 20%. In September 2020, the Company received early repayments for both principals and accrued interest from Juventas. For the year ended December 31, 2020, the Company recognized interest income of $351,000 and $375,000, respectively.

INVENTORIES

INVENTORIES	12 Months Ended
	Dec. 31, 2020
INVENTORIES
INVENTORIES	4. INVENTORIES Inventories at December 31, 2020 and 2019 consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31 (In thousands) 2020 ​ 2019 Finished goods ​ $ 1,356 $ 4,514 Raw materials ​ — ​ 28 Total ​ $ 1,356 ​ $ 4,542 ​ No provisions to write down the carrying amount of inventory have been recorded in the year ended December 31, 2020. Provisions to write-down the carrying amount of obsolete inventory related to ANDAs were $152,000, and were recorded as expenses in the consolidated statements of comprehensive loss for the year ended December 31, 2019.

LEASES

LEASES	12 Months Ended
	Dec. 31, 2020
LEASES
LEASES	5. LEASES As discussed in Note 2, effective January 1, 2019, the Company adopted Topic 842. At the inception of a contract, the Company determines if the arrangement is, or contains, a lease. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. Rent expense is recognized on a straight-line basis over the lease term. The Company has made accounting policy elections whereby it (i) does not recognize ROU assets or lease liabilities for short-term leases (those with original terms of 12-months or less) and (ii) combines lease and non-lease components for facilities leases, which primarily relate to ancillary expenses such as common area maintenance charges and management fees of its operating leases. Operating lease liabilities (see below) are included in accrued liabilities and other current liabilities, and other liabilities (noncurrent) in the consolidated balance sheets as of December 31, 2020. As of December 31, 2020, the Company did not have any finance leases. All of the Company’s existing leases as of December 31, 2020 are classified as operating leases. As of December 31, 2020, the Company has seven material operating leases for land, facilities and office equipment with remaining terms expiring from 2021 through 2069 and a weighted average remaining lease term of 38.37 years. The Company has fair value renewal options for many of the Company’s existing leases, none of which are considered reasonably certain of being exercised or included in the minimum lease term. Weighted average discount rates used in the calculation of the lease liability is 3.72%. The discount rates reflect the estimated incremental borrowing rate, which includes an assessment of the credit rating to determine the rate that the Company would have to pay to borrow, on a collateralized basis for a similar term, an amount equal to the lease payments in a similar economic environment. In November 2019, CASI Wuxi entered into a fifty-year lease agreement for the right to use state-owned land in China for the construction of a manufacturing facility. The land parcel is 74,028.40 square meters. The Company classifies this lease as an operating lease. The Company prepaid all of the lease payments for the land use right in 2019 in the amount of RMB45 million (equivalent to $6.5 million). During 2020, the Company entered into two 3-year lease agreements for office space in China each of which continue through August 2023 and September 2023, respectively, and one 5-year lease agreement for a Research and Development facility also in China which continues through March 2025. The Company recorded right-of-use assets of $1.3 million and related lease liabilities of $1.2 million at lease commencement date. The Company classifies these leases as operating leases. In the fourth quarter of 2020, the company terminated one lease of office space twelve months earlier than the lease term and recognized a loss of $13,000 from this lease termination. Rent expense for the years ended December 31, 2020 and December 31, 2019 was $1,600,000 and $1,315,000. There were no variable lease costs or sublease income for leased assets for the years ended December 31, 2020 and 2019. Right of use assets and liabilities as of December 31, 2020 and December 31, 2019 consolidated balance sheets were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) December 31, ​ 2020 2019 ​ Right of use assets ​ $ 8,696 ​ $ 8,708 ​ ​ ​ ​ ​ ​ ​ ​ ​ Accrued liabilities ​ $ 939 ​ $ 1,182 ​ Other liabilities ​ 965 ​ 1,019 ​ Total lease liabilities ​ $ 1,904 ​ $ 2,201 ​ ​ Supplemental cash flow information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (In thousands) ​ 2020 ​ 2019 Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ Operating cash flows ​ $ 1,375 ​ $ 1,315 ​ ​ ​ ​ ​ ​ ​ Right of use assets obtained in exchange for lease obligations: ​ $ 1,196 ​ $ 2,157 ​ A maturity analysis of the Company’s operating leases as of December 31, 2020 follows: Future undiscounted cash flows: ​ ​ ​ ​ ​ (In thousands) ​ 2021 $ 1,052 2022 ​ 626 2023 ​ 280 Thereafter ​ 42 Total ​ 2,000 ​ ​ ​ ​ Discount factor ​ (96) Lease liability ​ 1,904 Amounts due within 12 months ​ 939 Non-current lease liability ​ $ 965 ​

PROPERTY, PLANT AND EQUIPMENT

PROPERTY, PLANT AND EQUIPMENT	12 Months Ended
	Dec. 31, 2020
PROPERTY, PLANT AND EQUIPMENT
PROPERTY, PLANT AND EQUIPMENT	6. PROPERTY, PLANT AND EQUIPMENT In November 2019, CASI Wuxi entered into a lease agreement for the right to use state-owned land in China for the construction of a manufacturing facility. Pursuant to the agreement, CASI Wuxi commits to invest land use right and property, plant and equipment of RMB 1 billion (equivalent to $143 million). On August 27, 2020, CASI Wuxi entered into a Construction Project Contract (the "Construction Contract") with China Electronic System Engineering No. 2 Construction Co., Ltd. ("China Engineering"). Pursuant to the Construction Contract, CASI Wuxi will pay a contract price of RMB 74,588,000 (equivalent to $10,923,000) to retain China Engineering to complete the phase 1 project of CASI Wuxi's research and development production base, consisting of construction and installation of a combined factory building, warehouse, guard house and public works. The estimated completion date is October 2023. Construction in progress (“CIP”) is included in Property, Plant and Equipment (“PP&E”). CIP is stated at cost and includes costs incurred to acquire, construct, or install PP&E. CIP overhead is expensed as incurred. Construction in progress is not depreciated until such time when the asset is substantially completed and ready for its intended use. At December 31, 2020, CIP is $1.2 million. Furniture and equipment are stated at cost and are depreciated over their estimated useful lives of 3 to 5 years. Leasehold improvements are stated at cost and are amortized over the shorter of their useful lives or the lease term. Depreciation and amortization expense are determined on a straight-line basis. Depreciation and amortization expense were $562,000 and $603,000 in 2020 and 2019, respectively. Property, plant and equipment consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) ​ December 31, ​ 2020 2019 Furniture and equipment ​ $ 1,622 ​ $ 1,305 Leasehold improvements ​ 985 ​ 792 Construction in progress ​ ​ 1,193 ​ ​ — Total property, plant and equipment, gross ​ 3,800 ​ 2,097 Accumulated depreciation and amortization ​ ​ (1,322) ​ ​ (726) Impairment of property, plant and equipment ​ (416) ​ (386) ​ ​ $ 2,062 ​ $ 985 ​ The Company recognized no impairment during the year ended December 31, 2020, and $386,000 during the year ended December 31, 2019 related to equipment which was leased to a related party (see Note 19).

INTANGIBLE ASSETS

INTANGIBLE ASSETS	12 Months Ended
	Dec. 31, 2020
INTANGIBLE ASSETS
INTANGIBLE ASSETS	7. INTANGIBLE ASSETS Intangible assets include ANDAs that were acquired as part of 2018 asset acquisitions and US marketed generic products and capitalized cost related to a cloud computing arrangement (CCA). These intangible assets were originally recorded at relative estimated fair values based on the purchase price for the asset acquisitions and are stated net of accumulated amortization and impairment, if any. The ANDAs are amortized over their estimated useful lives of 13 years, using the straight-line method. The cloud computing arrangement is amortized over its useful life of 5 years. In February 2020, the Company entered into an agreement with Chartwell Rx Sciences, LLC (“Chartwell”) in which the Company sold and transferred the control of seven U.S. FDA-approved ANDAs to Chartwell in exchange for $450,000 in cash, which the Company received in March 2020. These ANDAs had a net book value of $0 at the time of sale. The Company is entitled to an additional $1 million, contingent upon Chartwell receiving certain FDA approvals relating to certain of these ANDAs. The Company recognized a gain on disposal of intangible assets in the amount of $450,000 in the accompanying consolidated statement of operations and comprehensive loss for the year ended December 31, 2020. The additional $1 million is treated as variable consideration. Because the amount of variable consideration is highly susceptible to factors outside the Company's influence and the Company’s experience with similar types of contracts is limited, the Company did not include the amount of variable consideration in recognition of gain on disposal of intangible assets for the year ended December 31, 2020. The Company will recognize the variable consideration and additional gain on disposal of intangible assets when the constraint on variable consideration is resolved, i.e., Chartwell receives relevant FDA approvals. Intangible assets at December 31, 2020 consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) ​ ​ ​ ​ ​ ​ ​ ​ Asset Purchase Price Accumulated Amortization Estimated useful lives ANDAs ​ $ 15,832 ​ $ (2,721) 13 years Others ​ ​ 197 ​ ​ (98) ​ 5 years Total ​ $ 16,029 ​ $ (2,819) ​ The changes in intangible assets for the year ended December 31, 2020 are as follows: ​ ​ ​ ​ ​ (In thousands) ​ Balance as of December 31, 2019 ​ $ 13,674 Additions ​ — Disposal of 7 ANDAs at $0 net book value ​ — Amortization expense ​ (1,289) Foreign currency translation adjustment ​ 825 Balance as of December 31, 2020 ​ $ 13,210 ​ Expected future amortization expense is as follows as of December 31, 2020: ​ ​ ​ ​ ​ (In thousands) ​ ​ ​ 2021 $ 1,321 2022 ​ 1,321 2023 ​ 1,321 2024 ​ 1,288 2025 ​ 1,288 2026 and thereafter ​ 6,671 ​

ASSETS HELD FOR SALE

ASSETS HELD FOR SALE	12 Months Ended
	Dec. 31, 2020
ASSETS HELD FOR SALE
ASSETS HELD FOR SALE	8. ASSETS HELD FOR SALE During the year ended December 31, 2020, the Company classified 14 ANDAs as assets held for sale as it committed to plans to sell these assets within one year and actively market the assets in their current condition at a price that is reasonable in relation to their estimated fair value. The Company reclassified the comparable balance sheet amounts related to these fourteen ANDAs in the amount of $3.2 million as of December 31, 2019 from intangible assets to assets held for sale. The Company recorded an impairment related to these assets held for sale of $1.5 million during the year ended December 31, 2020. In July 2020, the Company entered into an agreement with Rubicon Research Private Limited (“Rubicon”) in which the Company sold and transferred the control of four U.S. FDA-approved ANDAs to Rubicon in exchange for $1.25 million in cash, which the Company received in July 2020. These ANDAs had a net book value of $1.25 million at the time of sale resulting in no gain or loss on the sale. ​ In October 2020, the Company entered into an agreement with Chartwell pursuant to which the Company sold and transferred the control of 10 ANDAs to Chartwell in exchange for $1.0 million in cash, which the Company received in the fourth quarter of 2020. These ANDAs had a net book value of $0.3 million at the time of sale, resulting in a gain on sale of assets of $0.7 million in the fourth quarter of 2020. ​ Assets held-for-sale at December 31, 2019 consist of the following: ​ ​ ​ ​ ​ (In thousands) December 31, 2019 Cost of intangible assets $ 4,074 Accumulated amortization ​ ​ (853) ​ $ 3,221 ​

GRANTS

GRANTS	12 Months Ended
	Dec. 31, 2020
GRANTS
GRANTS	9. GRANTS In November 2019, CASI Wuxi entered into a fifty-year lease agreement for the right to use state-owned land in China for the construction of a manufacturing facility (see Note 5). In November 2019, the Company entered into a grant agreement with the Administrative Committee of Wuxi Huishan Economic Development Zone, under which, the Company is eligible for grants up to RMB 25 million (equivalent to $3.6 million) to support the development of CASI Wuxi’s manufacturing site. In April 2020, CASI Wuxi received RMB 15.9 million (equivalent to $2.2 million) from the Jiangsu Province Wuxi Huishan Economic Development Zone as a government grant for this development project which was recorded as deferred income in April 2020. The grant will be amortized over the term of the lease of the land. The Company recognized $35,000 of other income during the year ended December 31, 2020. ​

BANK BORROWINGS

BANK BORROWINGS	12 Months Ended
	Dec. 31, 2020
BANK BORROWINGS
BANK BORROWINGS	​ 10. BANK BORROWINGS ​ On November 3, 2020, Beijing Branch of China CITIC Bank Corporation Limited approved a guaranteed line of Credit (“Bank Borrowings) to the Company with maximum borrowings of RMB 10.0 million ($1.5 million). The joint and several liability guarantee was provided by Beijing Capital Financing Guarantee Co, Ltd. At December 31, 2020, the Company had outstanding borrowings under the Bank Borrowings of RMB 5.4 million ($826,000), which matures on November 7, 2021, and bears interest at a fixed rate of 3.35% per annum. Interest expense of $1,000 was recorded in the year ended December 31, 2020. ​

NOTE PAYABLE

NOTE PAYABLE	12 Months Ended
	Dec. 31, 2020
NOTE PAYABLE
NOTE PAYABLE	11. NOTES PAYABLE On April 27, 2020, M&T Bank approved a $465,595 loan to the Company under the Paycheck Protection Program (PPP) pursuant to the Coronavirus Aid, Relief and Economic Security (CARES) Act that was signed into law on March 27, 2020. The loan, evidenced by a promissory note to M&T Bank as lender and dated April 29, 2020, has a term of two years, is unsecured, and is guaranteed by the Small Business Administration (SBA). The loan bears interest at a fixed rate of one percent per annum. Some or all of the loan may be forgiven if the Company complies with certain relevant conditions. In June 2020, the PPP was amended through enactment of the Paycheck Protection Program Flexibility Act of 2020 (PPPFA). Under the new act, the Company’s payments of principal and interest are deferred until October 2021. The Company has until August 2021 to apply for loan forgiveness before potential loan payments would begin. Interest expense of $3,100 was recorded in the year ended December 31, 2020.

REDEEMABLE NONCONTROLLING INTER

REDEEMABLE NONCONTROLLING INTEREST	12 Months Ended
	Dec. 31, 2020
REDEEMABLE NONCONTROLLING INTEREST
REDEEMABLE NONCONTROLLING INTEREST	12. REDEEMABLE NONCONTROLLING INTEREST On December 26, 2018, the Company, together with Wuxi Jintou Huicun Investment Enterprise, a limited partnership organized under Chinese law (“Wuxi LP”) established CASI Wuxi to build and operate a manufacturing facility in the Wuxi Huishan Economic Development Zone in Jiangsu Province, China. The Company holds 80% of the equity interests in CASI Wuxi and will invest, over time, $80 million in CASI Wuxi. The Company’s investment will consist of (i) $21 million in cash (paid in February 2019), (ii) a transfer of selected ANDAs valued at $30 million (transferred in May 2019), and (iii) an additional $29 million cash payment within three years from the date of establishment of CASI Wuxi. Wuxi LP holds 20% of the equity interest in CASI Wuxi through its investment in RMB of $20 million in cash (paid in March 2019). As the transfer of ANDAs, valued at $30 million, was to the Company’s consolidated subsidiary (CASI Wuxi), the Company recognized the transfer of the ANDAs at their carrying value and did not recognize a gain on the transfer. Pursuant to the investment contract between the Company and Wuxi LP and Articles of Association of CASI Wuxi, the Company has the call option to purchase the 20% equity interest in CASI Wuxi held by Wuxi LP at any time within 5 years from the date of establishment of CASI Wuxi (i.e. up to December 26, 2023). Wuxi LP has the put option to require the Company to redeem the 20% equity interest in CASI Wuxi at any time after December 26, 2023. The redemption value under both the Company’s embedded put option and Wuxi LP’s embedded call option is equal to $20 million plus interest at the bank loan interest rate issued by the People's Bank of China for the period beginning with the initial capital contribution by Wuxi LP to the date of redemption. In addition, Wuxi LP has the put option to require the Company to redeem the 20% equity interest in CASI Wuxi at $20 million upon the occurrence of any of the following conditions: (i) the Company fails to fulfill its investment obligation to CASI Wuxi; (ii) CASI Wuxi suffers serious losses, discontinued operation, dissolution, goes into process of bankruptcy liquidation; or (iii) the Company substantially violates the investment contract and Articles of Association of CASI Wuxi. The investment of Wuxi LP in CASI Wuxi is treated as redeemable noncontrolling interest and is classified outside of permanent equity on the consolidated balance sheets because (1) the noncontrolling interest is not mandatorily redeemable financial instruments, and (2) it is redeemable at the option of the holder, or upon the occurrence of an event that is not solely within the control of the Company. The Company initially recorded the redeemable noncontrolling interest at its fair value of $20 million. The carrying amount of the redeemable noncontrolling interest is subsequently recorded at the greater of the amount of (1) the initial carrying amount, increased or decreased for the redeemable noncontrolling interest’s share of net income or loss in CASI Wuxi or (2) the redemption value, assuming the noncontrolling interest is redeemable at the balance sheet date. Accretion of the carrying amount of redeemable noncontrolling interest to the redemption value is recorded in additional paid-in capital. Changes in redeemable noncontrolling interest during the year ended December 31, 2020 and 2019 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (In thousands) ​ 2020 ​ 2019 ​ Balance at beginning of period ​ $ 20,670 $ — ​ Cash contribution by Wuxi LP ​ — ​ 20,000 ​ Share of CASI Wuxi net (loss)/income ​ (918) ​ (395) ​ Accretion of redeemable noncontrolling interest ​ 1,694 ​ 1,065 ​ Foreign currency translation adjustment ​ ​ 587 ​ ​ — ​ Balance at end of period ​ $ 22,033 $ 20,670 ​ ​

STOCKHOLDERS' EQUITY

STOCKHOLDERS' EQUITY	12 Months Ended
	Dec. 31, 2020
STOCKHOLDERS' EQUITY
STOCKHOLDERS' EQUITY	13. STOCKHOLDERS’ EQUITY The Company had 250 million of authorized common stock at December 31, 2020 and 2019, respectively. The Company had 5 million of authorized preferred stock as of December 31, 2020 and 2019. The Company held 79,545 of shares of common stock in treasury at its acquisition cost at December 31, 2020 and 2019. March 2021 Underwritten Public Offering ​ On March 24, 2021, the Company closed an underwriting agreement (the “Underwriting Agreement”) with Oppenheimer & Co. Inc., as representative of the several underwriters named therein (the “Underwriters”), providing for the offer and sale of 15,853,658 shares of the Company’s common stock (the “Offering”) at a price to the public of $2.05 per share. In addition, the Company granted the Underwriters an option to purchase up to an additional 2,378,048 shares of common stock, which terminates on the earlier of 30 days and the day before the Company files to the Securities and Exchange Commission (“SEC”) the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. The Offering closed on March 26, 2021. The gross proceeds to CASI from the Offering are approximately $32.5 million, excluding the over-allotment option and before deducting the underwriting discounts and commissions and offering expenses payable by CASI. Certain insiders, including CASI’s Chairman and Chief Executive Officer, purchased shares of common stock in the Offering at the public offering price and on the same terms as the other purchasers in this Offering. The Company has agreed to pay the underwriters a commission of 1% of the gross proceeds raised from certain such insiders, and 6% of the gross proceeds raised in the offering from other investors. ​ The Offering is being made by means of a written prospectus supplement and accompanying prospectus forming part of a shelf registration statement on Form S-3 (Registration Statement No. 333-250801), previously filed with the SEC on November 20, 2020, which was declared effective on December 2, 2020. The Company filed a final prospectus supplement, dated March 24, 2021, with the SEC relating to the Offering. Pursuant to the Underwriting Agreement, the Company’s directors and executive officers entered into agreements in substantially the form agreed to by the Underwriters providing for a 90-day “lock-up” period with respect to sales of specified securities, subject to certain exceptions. ​ The Company intends to use the net proceeds of this offering for working capital and general corporate purposes, which include, but are not limited to advancing the Company’s product portfolio, acquiring the rights to new product candidates and general and administrative expenses. “Shelf “Registration Statement On November 20, 2020, the Company filed a Form S-3 registration statement with the SEC utilizing a “shelf” registration process. In December 2020, the Form S-3 registration statement was declared effective by the SEC. Pursuant to this shelf registration statement, the Company may sell debt or equity securities in one or more offerings up to a total public offering price of $150 million. As a result of the Company’s failure to timely file a periodic report with the SEC in connection with the adoption of the Company’s amended and restated bylaws, absent a waiver of the Form S-3 eligibility requirements, the Company is ineligible to use or file new short form registration statements on Form S-3 until October 1, 2021, assuming the Company continues to timely file the required Exchange Act reports. In the interim, however, the Company may raise capital pursuant to a registration statement on Form S-1 or on a private placement basis. July 2020 Underwritten Public Offering On July 24, 2020, the Company closed an underwritten public offering of 23 million shares of common stock (the "Offering") and received gross proceeds of $43.7 million before deducting the underwriting discounts and commissions and offering expenses payable by CASI. Certain insiders, including CASI's Chairman and CEO, and CASI's President, purchased shares of common stock in the Offering at the public offering price and on the same terms as the other purchasers in this Offering. CASI's Chairman and CEO purchased 2,952,426 shares directly and ETP Global Fund LP purchased 1,200,000 shares. CASI's President purchased 20,152 shares. The Company is using the net proceeds of this offering for working capital and general corporate purposes, which include, but are not limited to advancing the Company’s product portfolio, acquiring the rights to new product candidates and general and administrative expenses. Common Stock Sales Agreements On February 23, 2018, the Company entered into a Common Stock Sales Agreement (the “Sales Agreement”) with H.C. Wainwright & Co., LLC (“HCW”). Pursuant to the terms of the Sales Agreement, the Company may sell from time to time, at its option, shares of the Company’s common stock, through HCW, as sales agent. On July 19, 2019, the Company entered into an amendment to the Sales Agreement reducing the maximum amount that may be sold under the Sales Agreement to $20 million. In 2018, the Company issued 143,248 shares under the Sales Agreement resulting in net proceeds to the Company of $475,000. As of December 31, 2020, $19.5 million remained available under the Sales Agreement. On July 19, 2019, the Company entered into an Open Market Sale Agreement SM During 2020, the Company issued 434,000 shares under the Open Market Agreement with net proceeds of $1,357,000. As of March 30, 2021, the Company has issued 493,000 shares with net proceeds of $1,539,000. As of March 30, 2021, $28.4 million remained available under the Open Market Agreement. ​ Stock purchase warrants activity for the year ended December 31, 2020 and 2019 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Weighted Average ​ Warrants Exercise Price Outstanding at December 31, 2018 11,781,825 ​ $ — Issued — ​ $ — Exercised (1,938,105) ​ $ 1.69 Expired — ​ $ — Outstanding at December 31, 2019 9,843,720 ​ $ 4.43 Issued — ​ $ — Exercised (82,304) ​ $ 1.69 Expired (1,489,707) ​ $ 3.75 Outstanding at December 31, 2020 8,271,709 ​ $ 4.58 Exercisable at December 31, 2020 8,271,709 ​ $ 4.58 ​ All outstanding warrants are equity classified.

NET LOSS PER SHARE

NET LOSS PER SHARE	12 Months Ended
	Dec. 31, 2020
NET LOSS PER SHARE
NET LOSS PER SHARE	14. NET LOSS PER SHARE Net loss per share (basic and diluted) was computed by dividing net loss attributable to common stockholders, considering the accretions to redemption value of the redeemable noncontrolling interest, by the weighted average number of shares of common stock outstanding. As of December 31, 2020, and 2019, outstanding stock options totaling 16,746,238 and 18,268,372, respectively, and outstanding warrants totaling 8,271,709 and 9,843,720, respectively, were anti-dilutive, and therefore, were not included in the computation of weighted average shares used in computing diluted loss per share. The following table sets forth the basic and diluted net loss per share computation and provides a reconciliation of the numerator and denominator for the periods presented: ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (In thousands, except per share data) 2020 ​ 2019 Numerator: ​ ​ ​ ​ Net loss attributable to CASI Pharmaceuticals, Inc. ​ $ (48,287) ​ $ (46,032) Denominator: ​ ​ ​ Weighted average number of common shares ​ 110,452 ​ 95,948 Denominator for basic and diluted net loss per share calculation ​ 110,452 ​ 95,948 Net loss per share ​ ​ ​ — Basic and diluted ​ $ (0.44) ​ $ (0.48) ​

EMPLOYEE BENEFIT PLAN

EMPLOYEE BENEFIT PLAN	12 Months Ended
	Dec. 31, 2020
EMPLOYEE BENEFIT PLAN
EMPLOYEE BENEFIT PLAN	15. EMPLOYEE BENEFIT PLAN The Company sponsors the CASI Pharmaceuticals, Inc. 401(k) Plan and Trust. The plan covers substantially all U.S. employees and enables participants to contribute a portion of salary and wages on a tax-deferred basis. Contributions to the plan by the Company are discretionary. Contributions by the Company totaled $250,000 and $217,000 in 2020 and 2019, respectively. Full time employees of the Company in the PRC participate in a government mandated defined contribution plan, pursuant to which certain pension benefits, medical care, employee housing fund and other welfare benefits are provided to employees. Chinese labor regulations require that the PRC subsidiaries of the Company make contributions to the government for these benefits based on certain percentages of the employees’ salaries. The Company has no legal obligation for the benefits beyond the contributions made. The total amounts for such employee benefits, which were expensed as incurred, were $1,542,000 and $1,780,000 for the years ended December 31, 2020 and 2019, respectively.

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	12 Months Ended
	Dec. 31, 2020
STOCK-BASED COMPENSATION
STOCK-BASED COMPENSATION	16. STOCK-BASED COMPENSATION The Company has adopted various stock compensation plans for executive, scientific and administrative personnel of the Company, as well as outside directors and consultants. In June 2019, the Company’s stockholders approved an amendment to the 2011 Long-Term Incentive Plan, increasing the number of shares of common stock reserved for issuance from 20,230,000 to 25,230,000 to be available for grants and awards. As of December 31, 2020, a total of 10,084,923 shares remained available for grant under the Company’s 2011 Long-Term Incentive Plan. The Company’s net loss for the twelve months ended December 31, 2020 and 2019 includes $7,821,000 and $7,310,000, respectively, of non-cash compensation expense related to the Company’s share-based compensation awards. The compensation expense related to the Company’s share-based compensation arrangements is recorded as components of general and administrative expense and research and development expense, as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended ​ ​ December 31, (In thousands) 2020 2019 Research and development ​ $ 245 ​ $ 466 Sales and Marketing ​ ​ 39 ​ ​ — General and administrative ​ 7,537 ​ 6,844 Share-based compensation expense ​ $ 7,821 ​ $ 7,310 ​ Compensation expense related to stock options is recognized over the requisite service period, which is generally the option vesting term of up to five years. Awards with performance conditions are expensed when it is probable that the performance condition will be achieved. For the years ended December 31, 2020 and 2019, $49,000 and $73,000 was expensed for share awards with performance conditions that became probable during the year, respectively. The Company uses the Black-Scholes-Merton valuation model to estimate the fair value of service based and performance-based stock options granted to employees. Option valuation models, including Black-Scholes-Merton, require the input of highly subjective assumptions, and changes in the assumptions used can materially affect the grant date fair value of an award. Expected Volatility Risk-Free Interest Rate Expected Term of Options Expected Dividend Yield Following are the weighted-average assumptions used in valuing the stock options granted to employees during the years ended December 31, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ Year ended ​ ​ December 31, ​ ​ 2020 2019 Expected volatility ​ 78.70 % 77.30 % Range of expected volatility ​ 75.84% to 81.63 % 75.50% to 84.48 % Range of risk free interest rate ​ 0.31% to 1.77 % 1.62% to 2.59 % Expected term of option ​ 6.10 years 6.05 years Expected dividend yield ​ 0.00 % 0.00 % ​ The weighted average fair value of stock options granted during the years ended December 31, 2020 and 2019 were $1.85 and $2.20, respectively. A summary of the Company’s stock option plans and changes in options outstanding under the plans during the years ended December 31, 2020 and 2019 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted Average ​ Weighted Average Remaining ​ ​ ​ ​ Number of Options Exercise Price Contractual Term In Years Aggregate Intrinsic Value Outstanding at December 31, 2018 18,429,308 ​ $ 2.44 ​ ​ Exercised (599,002) ​ $ 1.43 ​ ​ ​ $ 1,124,000 Granted 5,834,808 ​ $ 3.01 ​ ​ Expired (7,090) ​ $ 3.69 ​ ​ Forfeited (1,389,652) ​ $ 1.17 ​ ​ ​ ​ ​ Cancelled (4,000,000) ​ $ 3.22 ​ ​ Outstanding at December 31, 2019 18,268,372 ​ $ 2.58 ​ ​ ​ ​ ​ ​ Exercised (2,789,473) ​ $ 1.39 ​ ​ ​ $ 1,856,978 Granted 2,380,686 ​ $ 2.71 ​ ​ ​ Expired (117,722) ​ $ 5.06 ​ ​ Forfeited (995,625) ​ $ 3.78 ​ ​ Cancelled ​ - ​ $ - ​ ​ ​ ​ ​ ​ Outstanding at December 31, 2020 16,746,238 ​ $ 2.71 ​ $ 6.71 ​ $ 10,866,320 Vested and expected to vest at December 31, 2020 ​ 16,746,238 ​ $ 2.71 ​ $ 6.71 ​ $ 10,866,320 Exercisable at December 31, 2020 9,381,854 ​ $ 2.35 ​ $ 5.17 ​ $ 9,964,551 ​ The aggregate intrinsic value is calculated as the difference between (i) the closing price of the common stock at December 31, 2020 and (ii) the exercise price of the underlying awards, multiplied by the number of options that had an exercise price less than the closing price on the last trading day of the year. Cash received from option exercises under all share-based payment arrangements for the twelve months ended December 31, 2020 and 2019 was $3.9 million and $854,000, respectively. In March 2018, the Compensation Committee of the Board of Directors (the “Board”) approved a grant of stock options to Dr. Wei-Wu He, the Company’s Executive Chairman at the time, exercisable for 1.0 million shares of common stock that will vest and become exercisable on the first anniversary date of the grant. In addition, the Board approved the grant of a performance-based option covering 4.0 million shares of common stock that will vest if, within 18 months of the date of grant, specific operational and strategic milestones are achieved. In April 2019, the 2018 performance-based option awarded to Dr. He, the Company’s Chairman and CEO, covering 4 million shares of common stock was cancelled. At the date of cancellation, the performance condition of the option award was not expected to vest based on the original vesting conditions, and therefore no compensation cost was recognized on the cancellation date. On June 20, 2019, the Company’s stockholders approved a grant of stock options to Dr. He, as the Company’s Chairman and CEO at the 2019 Annual Meeting. Under the terms of the grant, Dr. He received a stock option covering 4 million shares of common stock, at an exercise price of $2.85, vesting upon the earlier of (i) the completion of a transformative event by the Company as determined at the discretion of the Company’s compensation committee and (ii) April 2, 2021, the second anniversary of the date of his appointment as CEO. The following summarizes information about stock options that are outstanding at December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding Options Exercisable ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Weighted ​ ​ ​ ​ Weighted ​ Number Remaining ​ Average ​ Number ​ Average Range of Outstanding at Contractual ​ Exercise ​ Exercisable at ​ Exercise Exercise Prices December 31, 2020 Life in Years ​ Price ​ December 31, 2020 ​ Price $0.00 - $1.00 ​ 1,273,853 5.19 ​ $ 0.87 ​ 1,273,853 ​ $ 0.87 $1.01 - $2.00 ​ 4,982,929 4.39 ​ $ 1.50 ​ 4,912,929 ​ $ 1.50 $2.01 - $4.00 ​ 8,955,456 8.25 ​ $ 2.94 ​ 2,231,072 ​ $ 3.10 $4.01 - $7.00 ​ 1,329,000 6.40 ​ $ 6.61 ​ 759,000 ​ $ 6.50 $7.01 - $9.00 ​ 205,000 7.50 ​ $ 8.23 ​ 205,000 ​ $ 8.23 ​ ​ 16,746,238 6.71 ​ $ 2.71 ​ 9,381,854 ​ $ 2.35 ​ As of December 31, 2020, there was $8,208,000 of total unrecognized compensation cost related to non-vested stock options, excluding not-probable performance condition options. That cost is expected to be recognized over a weighted-average period of 1.74 years.

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2020
INCOME TAXES
INCOME TAXES	17. INCOME TAXES For financial reporting purposes, loss before income taxes includes the following components: ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) 2020 2019 United States ​ $ (40,626) ​ $ (28,957) PRC ​ (6,885) ​ (16,405) Total ​ $ (47,511) ​ $ (45,362) ​ Significant components of the Company’s deferred income tax assets and liabilities as of December 31, 2020 and 2019 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (In thousands) 2020 2019 Deferred income tax assets: ​ ​ Net operating loss carryforwards ​ $ 78,790 ​ $ 94,828 Research and development credit carryforward ​ 6,244 ​ 7,740 Intangible assets ​ 8,049 ​ 5,733 Equity-based compensation ​ 4,436 ​ 5,423 Other ​ (2,533) ​ 396 Valuation allowance for deferred income tax assets ​ (94,986) ​ (114,120) Net deferred income tax assets ​ $ — ​ $ — ​ The Company has U.S. federal and state net operating loss (NOL) carryforwards of $324,707,000 at December 31, 2020. The Company also has People’s Republic of China (“PRC”) NOL carryforwards of $13,464,000 at December 31, 2020. The Company’s U.S. federal NOL carryforwards generated prior to 2018 begin to expire in 2021. The Company also has research and experimentation (“R&E”) tax credit carryforwards of $6,244,000 as of December 31, 2020 that begin to expire in 2021. Under the provisions of the Internal Revenue Code, the NOL and tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service and state tax authorities. NOL and tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders over a three-year period in excess of 50%, as defined under Sections 382 and 383 of the Internal Revenue Code of 1986, respectively, as well as similar state tax provisions. This could limit the amount of tax attributes that the Company can utilize annually to offset future taxable income or tax liabilities. The amount of the annual limitation, if any, will be determined based on the value of the Company immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. For financial reporting purposes, a 100% valuation allowance has been recognized to reduce the net deferred tax assets to zero because it is more likely than not that the Company could not generate sufficient taxable income in the future to realize the benefit of deferred income tax assets. A reconciliation of the provision for income taxes to the federal statutory rate is as follows: ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) 2020 2019 Tax benefit at statutory rate ​ $ (9,977) ​ $ (9,526) State taxes ​ (732) ​ (1,701) Attribute expiration ​ 13,707 ​ 12,461 Nondeductible expenses ​ ​ 358 ​ ​ 453 Deemed royalty ​ ​ 4,220 ​ ​ — Other ​ (54) ​ (608) Change in applicable tax rates ​ 11,612 ​ (7) Change in valuation allowance ​ (19,134) ​ (1,072) ​ ​ $ — ​ $ — ​ The Company had $2,581,000 of unrecognized tax benefits as of December 31, 2019 related to net R&E tax credit carryforwards. For the year ended December 31, 2020, there was a net reduction of unrecognized tax benefits of $499,000 related to R&E tax credits. The Company has a full valuation allowance at December 31, 2020 and 2019 against the full amount of its net deferred tax assets and, therefore, there was no impact on the Company’s financial position. The Company does not expect significant changes to the unrecognized benefit during 2020. As of December 31, 2020 and 2019, the Company did not accrue any interest related to uncertain tax positions. To date, there have been no interest or penalties charged to the Company related to income taxes. A reconciliation of the beginning and ending amount of gross unrecognized tax benefits is as follows: ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) 2020 2019 Unrecognized tax benefits balance at January 1 ​ $ 2,581 ​ $ 2,986 Reductions for tax positions of prior periods ​ (499) ​ (405) Additions for tax positions of current period ​ — ​ — Unrecognized tax benefits balance at December 31 ​ $ 2,082 ​ $ 2,581 ​ The Company and each of its PRC subsidiaries file income tax returns in the United States and the PRC, respectively. Due to the existence of tax attribute carryforwards (which are currently offset by a full valuation allowance), all of the Company’s tax returns since 1999 are open to examination by the taxing authorities. According to the PRC Tax Administration and Collection Law, the statute of limitations is three years if the underpayment of taxes is due to computational errors made by the taxpayer or the withholding agent. The statute of limitations is extended to five years under special circumstances where the underpayment of taxes is more than RMB100,000 ($14,334). In the case of transfer pricing issues, the statute of limitations is ten years. There is no statute of limitations in the case of tax evasion. The PRC tax returns for the Company’s PRC subsidiaries are open to examination by the PRC tax authorities for the tax years beginning in 2014.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 31, 2020
FAIR VALUE MEASUREMENTS
FAIR VALUE MEASUREMENTS	18. FAIR VALUE MEASUREMENTS The majority of the Company’s financial instruments (consisting of cash and cash equivalents, account receivable, accounts payable, accrued liabilities, notes payable and bank borrowings) are carried at cost which approximates their fair values due to the short-term nature of the instruments. The Company’s investment in equity securities is carried at fair value, and investment in convertible loan-AFS are carried at fair value (see Note 3). Fair value is the price that would be received from the sale of an asset or paid to transfer a liability assuming an orderly transaction in the most advantageous market at the measurement date. U.S. GAAP establishes a hierarchical disclosure framework which prioritizes and ranks the level of observability of inputs used in measuring fair value. These tiers include: ● Level 1—Quoted prices (unadjusted) in active markets that are accessible at the measurement date for identical assets or liabilities. The fair value hierarchy gives the highest priority to Level 1 inputs. ● Level 2—Observable market-based inputs other than quoted prices in active markets for identical assets or liabilities. ● Level 3—Unobservable inputs are used when little or no market data is available. The fair value hierarchy gives the lowest priority to Level 3 inputs. Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis The Company evaluates financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level at which to classify them each reporting period. This determination requires the Company to make subjective judgments as to the significance of inputs used in determining fair value and where such inputs lie within the hierarchy. The Company has equity investments in the common stock of two publicly traded companies. The Company’s investments in these equity securities are carried at their estimated fair value, with changes in fair value reported in the consolidated statement of operations and comprehensive loss each reporting period (see Note 3). The fair value of the common stock is based on quoted market price for the investees’ common stock, a Level 1 input. The Company has an equity investment in the warrants of a publicly traded company. The Company’s investment is carried at its estimated fair value, with changes in fair value reported in the consolidated statement of operations and comprehensive loss each reporting period (see Note 3). The fair value of the warrants was measured using observable market-based inputs other than quoted prices in active markets for identical assets or liabilities, level 2 inputs. The Company uses the Black-Scholes-Merton valuation model to estimate the fair value of warrants. Option valuation models, including Black-Scholes-Merton, require the input of highly subjective assumptions, and changes in the assumptions used can materially affect the fair value determination of a warrant. The following tables presents the Company’s financial assets and liabilities accounted for at fair value on a recurring basis as of December 31, 2020 and December 31, 2019, by level within the fair value hierarchy: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) ​ Fair Value at ​ ​ ​ ​ ​ ​ ​ ​ ​ Description December 31, 2020 Level 1 Level 2 Level 3 Investments in Current Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investments in common stock ​ $ 9,309 ​ $ 9,309 ​ $ — ​ $ — Investment in convertible loan-AFS ​ $ 83 ​ $ — ​ $ — ​ $ 83 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) Fair Value at ​ ​ ​ ​ ​ ​ ​ ​ ​ Description December 31, 2019 Level 1 Level 2 Level 3 Investments in Current Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment in common stock ​ $ 625 ​ $ 625 ​ $ — ​ $ — ​ Financial Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis The Company measures equity investments without readily determinable fair values at its cost, minus impairment, if any, plus or minus changes resulting from observable transactions of identical or similar securities of the same issuer. On September 29, 2020, the Company remeasured the investments in equity securities in Juventas (see Note 3) to the fair value. The Company estimated the fair value of these securities based on the transaction price of similar securities issued by the investee. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quantitative Information about Level 3 Fair Value Measurements ​ ​ (In Thousands) Fair Value at ​ ​ ​ ​ ​ ​ ​ September 29, 2020 ​ ​ ​ ​ ​ Description (remeasurement date) Valuation Techniques Unobservable Input Average/Median Investment in equity securities using measurement alternative ​ $ 12,872 Market comparable companies Multiples of selected comparable companies 5.3/1.1 ​ Non-Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis The Company has no non-financial assets and liabilities that are measured at fair value on a recurring basis. Non-Financial Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis ​ As of June 30, 2020, the intangible assets and assets held for sale with a total carrying amount of $3,087,000 were written down to their fair value of $1,550,000, resulting in an impairment charge of $1,537,000, which represents the difference between the carrying value of the intangible asset and assets held for sale and its fair value. The Company estimated the fair value using Level 2 inputs based on quoted price As of December 31, 2019, equipment leased to Juventas with a total carrying amount of $673,000 were written down to their fair value of $287,000, resulting in an impairment charge of $386,000, representing the difference between total carrying amount and fair value of these long-lived assets, which was calculated based on Level 3 Inputs. No impairment was recorded for the year ended December 31, 2020.

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	12 Months Ended
	Dec. 31, 2020
RELATED PARTY TRANSACTIONS
RELATED PARTY TRANSACTIONS	19. RELATED PARTY TRANSACTIONS Juventas. For license, investment and loan transactions with Juventas, refer to Note 1 and Note 3. Transactions with Juventas are considered to be related party transactions: ● T he Company’s CEO and Chairman is the chairman and a founding shareholder of Juventas ● The Company’s Chairman of the Audit Committee, is a founding partner of Panacea Venture, which is a current shareholder of Juventas. Panacea Venture is a global venture fund focusing on investments in healthcare and life science companies. In June 2019 and September 2020, a committee of independent directors of CASI negotiated the terms of the investment and license agreements and recommended that the board of directors approve the transactions. The Company’s CEO did not participate in the committee’s deliberations or the board of directors’ approval of the transaction. Spectrum/Acrotech. Based on the original licenses, the Company had supply agreements with Spectrum for the purchase of EVOMELA, ZEVALIN, and MARQIBO in China for quality testing purposes to support the Company’s application for import drug registration and for commercialization purposes. On March 1, 2019, Spectrum completed the sale of its portfolio of seven FDA-approved hematology/oncology products including EVOMELA, MARQIBO, and ZEVALIN to Acrotech. The original supply agreements with Spectrum for EVOMELA, MARQIBO, and ZEVALIN were assumed by Acrotech; Spectrum agreed to continue with a short-term supply agreement for EVOMELA for the initial commercial product supply for the greater China region. As part of the license arrangements with Spectrum, the Company issued to Spectrum a secured promissory note originally due March 17, 2016, which was subsequently amended and extended to September 17, 2019. The principal of the secured promissory note was $1.5 million and the coupon interest rate was 0.5%. The Company paid this note, including accrued interest in full during the year ended December 31, 2019. In 2018, the Company entered into commercial purchase obligation commitments for EVOMELA from Spectrum totaling $9.2 million under the short-term supply agreement for EVOMELA. All of these EVOMELA purchase commitments have been delivered as of October 2019. There were no transactions with Spectrum during the year ended December 31, 2020. For the year ended December 31, 2019, the transactions relating to the manufacturing and purchase of the EVOMELA commercial product supply amounted to $7.8 million. The amount due to Spectrum was $0.2 million as of December 31, 2019. The Company also accrued $2.6 million for material costs related to EVOMELA during the year ended December 31, 2019 which are included in accrued expenses. As of December 31, 2020, all amounts due to Spectrum have been settled. BioCheck. also the Chairman of BioCheck. Transactions with ETP, parent of BioCheck, and a more than 5% shareholder of the Company, are also considered to be related party transactions as Dr. Wei-Wu He, the Company’s CEO and Chairman is also the chairman of ETP. Since the Company required additional office space, in January 2020, the agreement was amended for annualized rents in the amount of $144,000 ($12,000 a month) with a stipulation that the new rent was retroactive to October 1, 2019. During the year ended December 31, 2020, the Company recognized rent expense of $144,000 and expects to recognize $63,000 of additional rent expense in 2021 related to this lease.

ACROTECH LICENSE ARRANGEMENTS

ACROTECH LICENSE ARRANGEMENTS	12 Months Ended
	Dec. 31, 2020
ACROTECH LICENSE ARRANGEMENTS
ACROTECH LICENSE ARRANGEMENTS	20. ACROTECH LICENSE ARRANGEMENTS The Company has product rights and perpetual exclusive licenses from Acrotech Biopharma L.L.C. (“Acrotech”) to develop and commercialize its commercial product EVOMELA® (Melphalan Hydrochloride For Injection) in the greater China region (which includes China, Taiwan, Hong Kong and Macau), as well as similar rights to assets ZEVALIN® (Ibritumomab Tiuxetan) and MARQIBO® (Vincristine Sulfate Liposome Injection). The exclusive licenses held by the Company were originally licensed from Spectrum Pharmaceuticals, which they later transferred to Acrotech. On December 3, 2018, the Company received NMPA’s approval for importation, marketing and sales in China and in August 2019 the Company launched EVOMELA in China. The NMPA required post-marketing study is ongoing and actively recruiting. The Company is currently evaluating future development options for ZEVALIN and MARQIBO due to the evolving standard of care environment, the rare and niche indications for these products, and its commitment to prioritize resources.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2020
COMMITMENTS AND CONTINGENCIES
COMMITMENTS AND CONTINGENCIES	21. COMMITMENTS AND CONTINGENCIES In conjunction with the BioInvent agreement entered into during 2020 (see Note 1), the Company is responsible for certain milestone and royalty payments. As of December 31, 2020, no milestones have been achieved. In conjunction with the Black Belt agreement entered into during 2019 (see Note 1), the Company is responsible for certain milestone and royalty payments. As of December 31, 2020, no milestones have been achieved. In conjunction with the Pharmathen agreement entered into during 2019 (see Note 1), the Company is responsible for one remaining milestone payment. As of December 31, 2020, the remaining milestone has not been met. In conjunction with the Laurus Labs agreement entered into during 2018, the Company is responsible for certain remaining milestone payments. As of December 31, 2020, the remaining milestones have not been met. In November 2019, CASI Wuxi entered into a lease agreement for the right to use state-owned land in China for the construction of a manufacturing facility. Pursuant to the agreement, CASI Wuxi commits to invest land use right and property, plant and equipment of RMB1 billion (equivalent to $143 million) within three years from the date of establishment of CASI Wuxi. On August 27, 2020, CASI Wuxi entered into a Construction Project Contract (the "Construction Contract") with China Electronic System Engineering No. 2 Construction Co., Ltd. ("China Engineering"). Pursuant to the Construction Contract, CASI Wuxi will pay a contract price of RMB 74,588,000 (equivalent to $10,923,000) to retain China Engineering to complete the phase 1 project of CASI Wuxi's research and development production base, consisting of construction and installation of a combined factory building, warehouse, guard house and public works. The estimated completion date is October 2023. The Company is subject in the normal course of business to various legal proceedings in which claims for monetary or other damages may be asserted. Management does not believe such legal proceedings, unless otherwise disclosed herein, are material.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	12 Months Ended
	Dec. 31, 2020
SUBSEQUENT EVENTS
SUBSEQUENT EVENTS	22. SUBSEQUENT EVENTS Cleave Investment In March 2021, the Company entered into an exclusive license agreement with Cleave Therapeutics, Inc. (“Cleave”)for the development and commercialization of CB-5339, a novel VCP/p97 inhibitor, in mainland China, Taiwan, Hong Kong and Macau. CB-5339, an oral second-generation, small molecule VCP/p97 inhibitor, is being evaluated in a Phase 1 clinical trial in patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS), while the National Cancer Institute (NCI) is sponsoring and evaluating CB-5339 in a Phase 1 clinical trial of patients with solid tumors and lymphomas. Under the terms of the agreement, Cleave and CASI will develop CB-5339 in both hematological malignancies and solid tumors, with CASI responsible for development and commercialization in China and associated markets. Cleave received a $5.5 million upfront payment and is eligible to receive up to $74 million in development and commercial milestone payments plus tiered royalties in the high-single to mid-double-digit range on net sales of CB-5339. In addition to the upfront cash payment, CASI made a $5.5 million investment in Cleave through a convertible note. Bank Borrowings Under the guaranteed line of Credit approved by Beijing Branch of China CITIC Bank Corporation Limited on November 3, 2020 (See Note 10), the Company had additional bank borrowings of RMB 4.6 million ($0.7 million) on February 3, 2021, of which RMB 3.0 million ($0.5 million) matures on September 2, 2021 and the remainder balance matures on November 7, 2021. These additional bank borrowings bear interest at a fixed rate of 3.72% per annum. March 2021 Underwritten Public Offering On March 24, 2021, the Company closed an underwriting agreement (the “Underwriting Agreement”) with Oppenheimer & Co. Inc., as representative of the several underwriters named therein (the “Underwriters”), providing for the offer and sale of 15,853,658 shares of the Company’s common stock (the “Offering”) at a price to the public of $2.05 per share. In addition, the Company granted the Underwriters an option to purchase up to an additional 2,378,048 shares of common stock, which terminates on the earlier of 30 days and the day before the Company files to the Securities and Exchange Commission (“SEC”) the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. The Offering closed on March 26, 2021. The gross proceeds to CASI from the Offering are approximately $32.5 million, excluding the over-allotment option and before deducting the underwriting discounts and commissions and offering expenses payable by CASI. Certain insiders, including CASI’s Chairman and Chief Executive Officer, purchased shares of common stock in the Offering at the public offering price and on the same terms as the other purchasers in this Offering. The Company has agreed to pay the underwriters a commission of 1% of the gross proceeds raised from certain such insiders, and 6% of the gross proceeds raised in the offering from other investors. ​ The Offering is being made by means of a written prospectus supplement and accompanying prospectus forming part of a shelf registration statement on Form S-3 (Registration Statement No. 333-250801), previously filed with the SEC on November 20, 2020, which was declared effective on December 2, 2020. The Company filed a final prospectus supplement, dated March 24, 2021, with the SEC relating to the Offering. Pursuant to the Underwriting Agreement, the Company’s directors and executive officers entered into agreements in substantially the form agreed to by the Underwriters providing for a 90-day “lock-up” period with respect to sales of specified securities, subject to certain exceptions.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2020
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”).
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The Company's significant accounting estimates relate to recoverability of operating lease right-of-use assets, intangible assets and long-term investments, net realizable value and obsolescence allowance for inventory, deferred tax assets and valuation allowance, allowance for doubtful accounts, stock-based arrangements and fair value of investments in equity securities in Juventas. Management bases its estimates on historical experience and on various other assumptions that it believes are reasonable under the circumstances. Actual results may differ from those estimates, and such differences may be material to the consolidated financial statements.
Consolidation	Consolidation The accompanying consolidated financial statements include the accounts of the Company and its subsidiaries, in which CASI, directly or indirectly, has a controlling financial interest. These subsidiaries include Miikana Therapeutics, Inc. ("Miikana"), CASI China, CASI Wuxi and CASI Biopharmaceuticals. CASI China is a non-stock Chinese entity with 100% of its interest owned by CASI. CASI China received approval for a business license from the Beijing Industry and Commercial Administration in August 2012 and has operating facilities in Beijing. CASI Wuxi was established on December 26, 2018 in China to develop a manufacturing facility in China. CASI Biopharmaceuticals is a wholly owned subsidiary of CASI Wuxi and was established in April 2019. The Company controls CASI Wuxi through 80% voting rights. Accordingly, the financial statements of CASI Wuxi have been consolidated in the Company's consolidated financial statements since its inception. All inter-company balances and transactions have been eliminated in consolidation. The Company currently operates in one operating segment, which is the development of innovative therapeutics addressing cancer and other unmet medical needs for the global market.
Foreign Currency Translation and Transactions	Foreign Currency Translation and Transactions The accompanying consolidated financial statements of the Company are reported in US dollars. The financial position and results of operations of the Company’s subsidiaries in the PRC are measured using the Renminbi (RMB), which is the local and functional currency of these entities. Assets and liabilities of the Company’s PRC subsidiaries are translated into US$ using the exchange rates in effect at the consolidated balance sheet date. The revenues and expenses of these entities are translated into US$ at the weighted average exchange rates for the period. The resulting translation gains (losses) are recorded in accumulated other comprehensive income (loss) as a component of shareholders’ equity. Transactions denominated in foreign currencies are remeasured into the functional currency at the exchange rates prevailing on the transaction dates. Foreign currency denominated financial assets and liabilities are remeasured at the exchange rates prevailing at the balance sheet date. Net gains or losses resulting from foreign currency denominated transactions are recorded in foreign exchange gain (losses) in the consolidated statements of operations.
Revenue Recognition	Revenue Recognition Product sales recognized in the consolidated statements of operations are considered revenue from contracts with customers and, accordingly, the Company recognizes revenue using the following steps: ● Identification of the contract, or contracts, with a customer; ● Identification of the performance obligations in the contract; ● Determination of the transaction price, including the identification and estimation of variable consideration; ● Allocation of the transaction price to the performance obligations in the contract; and ● Recognition of revenue when the Company satisfies a performance obligation. The Company recognizes revenue on sales of EVOMELA when the control of the product is transferred to the distributor, which occurs upon delivery of the product to the carrier appointed by the distributor, in an amount that reflects the consideration to which the Company expects to be entitled to in exchange for the product, excluding amounts collected on behalf of third parties (e.g. value-added taxes). Payment terms for these sales are due within 90 days. The arrangement does not include any variable consideration. The costs of assurance type warranties that provide the customer the right to exchange purchased product that does meet appropriate quality standards are recognized when they are probable and are reasonably estimable. There was no product exchange during the years ended December 31, 2020 and 2019. As of December 31, 2020 and 2019, the Company did not incur, and therefore did not defer, any material costs to obtain or fulfill contracts. The Company did not have any contract assets or contract liabilities as of December 31, 2020 and 2019.
Concentrations of Risk	Concentrations of Risk Cash Concentration Risk The Company maintains its U.S. and RMB cash in bank deposit accounts, which, at times, may exceed regulated insured limits. The Company believes it is not exposed to significant credit risk on cash and cash equivalents. Vendor Concentration Risk The Company has a sole supplier for its EVOMELA product. Through the second quarter of 2020, it was sourced solely from Spectrum Pharmaceuticals, Inc. (“Spectrum”) and its suppliers. Starting with the third quarter of 2020, and all future needs will be sourced from Acrotech and its suppliers. The Company’s ability to select other providers of EVOMELA is limited by FDA regulations. Accounts Receivable and Credit Concentration CRGK is the sole customer of the Company's EVOMELA product sales in China. All consolidated revenues for the year ended December 31, 2020 and 2019 were generated from sales to CRGK in China, and all the Company's accounts receivable balance as of December 31, 2020 and 2019 were due from CRGK. Accounts receivable consist of CRGK receivables of $4.6 million and $1.3 million as of December 31, 2020 and 2019, respectively. The Company extends credit to CRGK on an unsecured basis and maintains an allowance for doubtful accounts for estimated losses inherent in its accounts receivable. In establishing the required allowance, management considers the historical losses, customer’s financial condition, the amount of accounts receivables in dispute, the accounts receivables aging and the customer’s payment pattern. The Company determined that no allowance for doubtful accounts were necessary as of December 31, 2020 and 2019. The balance of accounts receivable as of December 31, 2020 has been subsequently collected.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The majority of the Company’s financial instruments (consisting principally of cash and cash equivalents, accounts receivable, prepaid expenses, accounts payable, accrued liabilities, bank borrowings, and notes payable) are carried at cost which approximates their fair values due to the short-term nature of the instruments. The Company’s investment in equity securities is carried at fair value, and its investment in convertible loan-AFS are carried at fair value (see Note 3). The Company also had a note payable which was paid off during the year ended December 31, 2019 (see Note 11). See Note 18 for additional fair value disclosures.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents include cash and highly liquid investments with original maturities of less than 90 days that are readily convertible to known amounts of cash.
Inventories	Inventories Inventories consist of EVOMELA finished goods and raw materials to be used in production of ANDAs and are stated at the lower of cost or net realizable value. Cost is determined using a first-in, first-out method. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. Adjustments are recorded to write down the carrying amount of any obsolete and excess inventory to its estimated net realizable value based on historical and forecasted demand.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at cost, less accumulated depreciation and impairment, if any. Costs incurred in the construction of property, plant and equipment, including down payments and progress payments, are initially capitalized as construction-in-progress and transferred into their respective asset categories when the assets are ready for their intended use, at which time depreciation commences. Furniture and equipment are depreciated over their estimated useful lives of 3
Costs of Revenues	Costs of Revenues Costs of revenues consist primarily of the cost of inventories of EVOMELA and sales-based royalties related to the sale of EVOMELA.
Investments	Investments Investment in equity securities with readily determinable fair value are measured at fair values, and any changes in fair value are recognized in earnings. Where the fair value of an investment in equity securities is not readily determinable, the Company recognizes such investment in long-term investments, and uses the measurement alternative of cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. For equity investments measured at fair value with changes in fair value recorded in earnings, the Company does not assess whether those securities are impaired. For equity investments without readily determinable fair value, at each reporting period, the Company makes a qualitative assessment considering impairment indicators to evaluate whether the investment is impaired. Impairment indicators that the Company considers include, but are not limited to, (i) the deterioration of earnings performance, credit rating, asset quality, or business prospects of the investee, (ii) a significant adverse change in the regulatory, economic, or technological environment of the investee, (iii) a significant adverse change in the general market condition of either the geographic area or the industry in which the investee operates. If a qualitative assessment indicates that the investment is impaired, the Company has to estimate the investment’s fair value and if the fair value is less than the investment’s carrying value, the Company recognizes an impairment loss in non-operating expenses equal to the difference between the carrying value and fair value. Dividend income is recognized in other income when earned.
Leases	Leases The Company adopted Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) Prior to the adoption of ASC 842, operating leases were not recognized on the balance sheet of the Company, instead rent expenses with fixed escalating payments and/or rent holidays were recognized on a straight-line basis over the lease term. Upon adoption of ASC 842, ROU assets and lease liabilities are recognized upon lease commencement for operating leases based on the present value of lease payments over the lease term. As the rate implicit in the lease cannot be readily determined, the Company uses incremental borrowing rate at the lease commencement date in determining the imputed interest and present value of lease payments. The incremental borrowing rate was determined based on the rate of interest that the Company would have to borrow an amount equal to the lease payments on a collateralized basis over a similar term. The incremental borrowing rate is primarily influenced by the risk-free interest rate of China and the US, the Company’s credit rating and lease term, and is updated for measurement of new lease liabilities. For operating leases, the Company recognizes a single lease cost on a straight-line basis over the remaining lease term. The Company has elected not to recognize ROU assets or lease liabilities for leases with an initial term of 12 months or less; the Company recognizes lease expense for these leases on a straight-line basis over the lease term. In addition, the Company has elected not to separate non-lease components (e.g., common area maintenance fees) from the lease components. Land use rights acquired are assessed in accordance with ASC 842 and recognized in right-of-use assets if they meet the definition of lease.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets Long-lived assets, including property, plant and equipment, operating lease right-of-use (“ROU”) assets and intangible assets subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Such events and circumstances include the use of the asset or asset group in current research and development projects and any potential alternative uses of the asset or asset group. If circumstances require a long-lived asset or asset group be tested for possible impairment, the Company first compares undiscounted cash flows expected to be generated by that asset or asset group to its carrying value. If the carrying value of the long-lived asset or asset group is not recoverable on an undiscounted cash flow basis, an impairment is recognized to the extent that the carrying value exceeds its fair value. Fair value is determined through various valuation techniques including discounted cash flow models, quoted market values and third-party independent appraisals, as considered necessary. Impairment charges related to property, plant and equipment were $0 and $386,000 for the years ended in December 31, 2020 and 2019, respectively. Impairment charges related to intangibles were $1.5 million and $0 for the years ended in December 31, 2020 and 2019, respectively.
Research and Development Expenses	Research and Development Expenses Research and development expenses consist primarily of compensation and other expenses related to research and development personnel, research collaborations, costs associated with pre-clinical testing and clinical trials of the Company’s product candidates, including the costs of manufacturing drug substance and drug product, regulatory maintenance costs, and facilities expenses, along with the amortization of acquired ANDAs. Research and development costs are expensed as incurred.
Stock-Based Compensation	Stock-Based Compensation The Company records compensation expense associated with service and performance-based stock options in accordance with provisions of authoritative guidance. The estimated fair value of service-based awards is determined using option pricing models that use unobservable inputs and is generally recognized on a straight-line basis over the requisite service period and based on the proportionate amount of the requisite service period that has been rendered during each reporting period. The estimated fair value of performance-based awards is measured on the grant date and is recognized when it is determined that it is probable that the performance condition will be achieved.
Government Grants	Government Grants Government grants are recognized when there is reasonable assurance that the Company will comply with required conditions and the grants will be received. Government grants related to assets are presented as deferred income that is recognized on a systematic basis over the useful life of the asset.
Income Taxes	Income Taxes Income tax expense is recognized using the asset and liability method. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities and operating loss and tax credit carryforwards as measured by the enacted tax rates that will be in effect when these differences reverse. A valuation allowance is provided to reduce the amount of deferred income tax assets if it is considered more likely than not that some portion or all of the deferred income tax assets will not be realized. The Company recognizes in its consolidated financial statements the impact of a tax position if a tax return position or future tax position is “more likely-than-not” to be sustained upon examination, based on the technical merits of the position. Tax positions that meet the “more-likely-than-not” recognition threshold are measured at the largest amount of tax benefit that has a greater than fifty percent likelihood of being realized upon settlement. The Company recognizes interest and penalties related to uncertain tax positions, if any, in income tax expense.
Net Loss Per Share	Net Loss Per Share Net loss per share (basic and diluted) was computed by dividing net loss attributable to common shareholders by the weighted average number of shares of common stock outstanding. As of December 31, 2020, and 2019, outstanding stock options totaling 16,746,238 and 18,268,372, respectively, and outstanding warrants totaling 8,271,709 and 9,843,720, respectively, were anti-dilutive, and therefore, were not included in the computation of weighted average shares used in computing diluted loss per share.
New Accounting Pronouncements	New Accounting Pronouncements Recently Adopted Pronouncements Effective January 1, 2019, the Company adopted Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2016-02, Leases (“Topic 842”). The guidance amends the accounting requirements for leases and requires lessees to recognize assets and liabilities related to long-term leases on the balance sheets and expands disclosure requirements regarding leasing arrangements. The Company adopted this guidance on a modified retrospective basis and used the following practical expedients: ● The Company did not reassess if any expired or existing contracts are or contain leases; ● The Company did not reassess the classification of any expired or existing leases. Upon adoption of the new guidance on January 1, 2019, the Company recorded right of use assets of $3.0 million and recognized lease liabilities of $3.2 million. There was no cumulative effect impact to accumulated deficit as of January 1, 2019. No adjustments were made to prior comparative periods. In August 2018, the FASB issued ASU 2018-15, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The new guidance requires a customer in a cloud computing arrangement (i.e., hosting arrangement) that is a service contract to follow the internal-use software guidance in ASC 350-40 to determine which implementation costs to capitalize as assets or expense as incurred. Capitalized implementation costs related to a hosting arrangement that is a service contract will be amortized over the term of the hosting arrangement, beginning when the module or component of the hosting arrangement is ready for its intended use. The update is effective for calendar-year public business entities in 2020. For all other calendar-year entities, it is effective for annual periods beginning in 2021 and interim periods in 2022. Early adoption is permitted. The Company early adopted this guidance effective January 1, 2019. The net impact to the financial statements was $140,000 of capitalized cost. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement. ASU 2018-13 eliminates, adds and modifies certain disclosure requirements for fair value measurements. The amendments applicable to the disclosures of changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial year of adoption. This ASU is effective for all entities for fiscal years beginning after December 15, 2019, including interim periods therein. All other amendments should be applied retrospectively to all periods presented upon their effective date. Early adoption is permitted, and an entity is also permitted to early adopt any removed or modified disclosures and delay adoption of the additional disclosures until their effective date. The Company adopted this guidance effective January 1, 2020. The adoption of this new accounting standard did not have a significant impact on the Company's consolidated financial statements. Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments — Credit Losses (Topic 326) (“ASU 2016-13”) and subsequent amendments to the initial guidance including ASU No. 2018-19, ASU No. 2019-04, and ASU No. 2019-05 (collectively, “Topic 326”). Topic 326 requires entities to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. This replaces the existing incurred loss model and is applicable to the measurement of credit losses on financial assets measured at amortized cost. This standard is effective for public business entities, excluding entities eligible to be smaller reporting companies for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. For all other entities, this standard is effective for annual and interim periods beginning after December 15, 2022 and early adoption is permitted for annual and interim periods beginning after December 15, 2018. As a smaller reporting company, the Company expects to adopt this standard in fiscal year 2023. The Company is currently assessing the impact that the adoption of this ASU will have on the consolidated financial statements. There are no other recently issued accounting pronouncements that are expected to have a material effect on the Company’s financial position, results of operations or cash flows.

INVESTMENT IN EQUITY SECURITI_2

INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS (Tables)	12 Months Ended
	Dec. 31, 2020
INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS
Schedule of investment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ ​ (In thousands) ​ ​ ​ ​ ​ ​ unrealized ​ Aggregate fair Description Classification Cost gains value MaxCyte - equity interest Investment ​ $ — ​ $ 2,729 ​ $ 2,729 BioInvent - equity interest Investment ​ $ 5,661 ​ $ 919 ​ $ 6,580
Schedule of components of long-term investments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (In thousands) 2020 2019 Available-for-sale debt securities: ​ ​ Black Belt Tx Limited - convertible loan ​ $ 83 ​ $ — Securities measured at fair value: ​ ​ ​ ​ ​ ​ BioInvent International AB - warrants ​ ​ 840 ​ ​ — Equity securities without readily determinable fair value: ​ ​ Black Belt Tx Limited - equity interest ​ 2,250 ​ 2,250 Juventas Cell Therapy Ltd - equity interest ​ 26,059 ​ 11,355 Juventas Cell Therapy Ltd - put option ​ 210 ​ 433 Total ​ $ 29,442 ​ $ 14,038

INVENTORIES (Tables)

INVENTORIES (Tables)	12 Months Ended
	Dec. 31, 2020
INVENTORIES
Schedule of components of inventories	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31 (In thousands) 2020 ​ 2019 Finished goods ​ $ 1,356 $ 4,514 Raw materials ​ — ​ 28 Total ​ $ 1,356 ​ $ 4,542

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 31, 2020
LEASES
Schedule of right of use assets and liabilities on condensed balance sheet	​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) December 31, ​ 2020 2019 ​ Right of use assets ​ $ 8,696 ​ $ 8,708 ​ ​ ​ ​ ​ ​ ​ ​ ​ Accrued liabilities ​ $ 939 ​ $ 1,182 ​ Other liabilities ​ 965 ​ 1,019 ​ Total lease liabilities ​ $ 1,904 ​ $ 2,201 ​
Schedule of supplemental cash flow information	​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (In thousands) ​ 2020 ​ 2019 Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ Operating cash flows ​ $ 1,375 ​ $ 1,315 ​ ​ ​ ​ ​ ​ ​ Right of use assets obtained in exchange for lease obligations: ​ $ 1,196 ​ $ 2,157
Schedule of future undiscounted cash flows	​ ​ ​ ​ ​ (In thousands) ​ 2021 $ 1,052 2022 ​ 626 2023 ​ 280 Thereafter ​ 42 Total ​ 2,000 ​ ​ ​ ​ Discount factor ​ (96) Lease liability ​ 1,904 Amounts due within 12 months ​ 939 Non-current lease liability ​ $ 965

PROPERTY, PLANT AND EQUIPMENT (

PROPERTY, PLANT AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2020
PROPERTY, PLANT AND EQUIPMENT
Schedule of property and equipment	Property, plant and equipment consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) ​ December 31, ​ 2020 2019 Furniture and equipment ​ $ 1,622 ​ $ 1,305 Leasehold improvements ​ 985 ​ 792 Construction in progress ​ ​ 1,193 ​ ​ — Total property, plant and equipment, gross ​ 3,800 ​ 2,097 Accumulated depreciation and amortization ​ ​ (1,322) ​ ​ (726) Impairment of property, plant and equipment ​ (416) ​ (386) ​ ​ $ 2,062 ​ $ 985

INTANGIBLE ASSETS (Tables)

INTANGIBLE ASSETS (Tables)	12 Months Ended
	Dec. 31, 2020
INTANGIBLE ASSETS
Schedule of net definite-lived intangible assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) ​ ​ ​ ​ ​ ​ ​ ​ Asset Purchase Price Accumulated Amortization Estimated useful lives ANDAs ​ $ 15,832 ​ $ (2,721) 13 years Others ​ ​ 197 ​ ​ (98) ​ 5 years Total ​ $ 16,029 ​ $ (2,819)
Schedule of changes in intangible assets	​ ​ ​ ​ ​ (In thousands) ​ Balance as of December 31, 2019 ​ $ 13,674 Additions ​ — Disposal of 7 ANDAs at $0 net book value ​ — Amortization expense ​ (1,289) Foreign currency translation adjustment ​ 825 Balance as of December 31, 2020 ​ $ 13,210
Schedule of expected future amortization expense	​ ​ ​ ​ ​ (In thousands) ​ ​ ​ 2021 $ 1,321 2022 ​ 1,321 2023 ​ 1,321 2024 ​ 1,288 2025 ​ 1,288 2026 and thereafter ​ 6,671

ASSETS HELD FOR SALE (Tables)

ASSETS HELD FOR SALE (Tables)	12 Months Ended
	Dec. 31, 2020
ASSETS HELD FOR SALE
Schedule of components of assets held-for-sale	​ ​ ​ ​ ​ (In thousands) December 31, 2019 Cost of intangible assets $ 4,074 Accumulated amortization ​ ​ (853) ​ $ 3,221

REDEEMABLE NONCONTROLLING INT_2

REDEEMABLE NONCONTROLLING INTEREST (Tables)	12 Months Ended
	Dec. 31, 2020
REDEEMABLE NONCONTROLLING INTEREST
Schedule of changes in redeemable noncontrolling interest	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (In thousands) ​ 2020 ​ 2019 ​ Balance at beginning of period ​ $ 20,670 $ — ​ Cash contribution by Wuxi LP ​ — ​ 20,000 ​ Share of CASI Wuxi net (loss)/income ​ (918) ​ (395) ​ Accretion of redeemable noncontrolling interest ​ 1,694 ​ 1,065 ​ Foreign currency translation adjustment ​ ​ 587 ​ ​ — ​ Balance at end of period ​ $ 22,033 $ 20,670 ​

STOCKHOLDERS' EQUITY (Tables)

STOCKHOLDERS' EQUITY (Tables)	12 Months Ended
	Dec. 31, 2020
STOCKHOLDERS' EQUITY
Schedule of stock purchase warrants activity	​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Weighted Average ​ Warrants Exercise Price Outstanding at December 31, 2018 11,781,825 ​ $ — Issued — ​ $ — Exercised (1,938,105) ​ $ 1.69 Expired — ​ $ — Outstanding at December 31, 2019 9,843,720 ​ $ 4.43 Issued — ​ $ — Exercised (82,304) ​ $ 1.69 Expired (1,489,707) ​ $ 3.75 Outstanding at December 31, 2020 8,271,709 ​ $ 4.58 Exercisable at December 31, 2020 8,271,709 ​ $ 4.58

NET LOSS PER SHARE (Tables)

NET LOSS PER SHARE (Tables)	12 Months Ended
	Dec. 31, 2020
NET LOSS PER SHARE
Schedule of basic and diluted net loss per share	​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (In thousands, except per share data) 2020 ​ 2019 Numerator: ​ ​ ​ ​ Net loss attributable to CASI Pharmaceuticals, Inc. ​ $ (48,287) ​ $ (46,032) Denominator: ​ ​ ​ Weighted average number of common shares ​ 110,452 ​ 95,948 Denominator for basic and diluted net loss per share calculation ​ 110,452 ​ 95,948 Net loss per share ​ ​ ​ — Basic and diluted ​ $ (0.44) ​ $ (0.48)

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	12 Months Ended
	Dec. 31, 2020
STOCK-BASED COMPENSATION
Schedule of compensation expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended ​ ​ December 31, (In thousands) 2020 2019 Research and development ​ $ 245 ​ $ 466 Sales and Marketing ​ ​ 39 ​ ​ — General and administrative ​ 7,537 ​ 6,844 Share-based compensation expense ​ $ 7,821 ​ $ 7,310
Schedule of weighted-average assumptions used in valuing the stock options	​ ​ ​ ​ ​ ​ ​ ​ Year ended ​ ​ December 31, ​ ​ 2020 2019 Expected volatility ​ 78.70 % 77.30 % Range of expected volatility ​ 75.84% to 81.63 % 75.50% to 84.48 % Range of risk free interest rate ​ 0.31% to 1.77 % 1.62% to 2.59 % Expected term of option ​ 6.10 years 6.05 years Expected dividend yield ​ 0.00 % 0.00 %
Schedule of stock option plans and of changes in options outstanding under the plans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted Average ​ Weighted Average Remaining ​ ​ ​ ​ Number of Options Exercise Price Contractual Term In Years Aggregate Intrinsic Value Outstanding at December 31, 2018 18,429,308 ​ $ 2.44 ​ ​ Exercised (599,002) ​ $ 1.43 ​ ​ ​ $ 1,124,000 Granted 5,834,808 ​ $ 3.01 ​ ​ Expired (7,090) ​ $ 3.69 ​ ​ Forfeited (1,389,652) ​ $ 1.17 ​ ​ ​ ​ ​ Cancelled (4,000,000) ​ $ 3.22 ​ ​ Outstanding at December 31, 2019 18,268,372 ​ $ 2.58 ​ ​ ​ ​ ​ ​ Exercised (2,789,473) ​ $ 1.39 ​ ​ ​ $ 1,856,978 Granted 2,380,686 ​ $ 2.71 ​ ​ ​ Expired (117,722) ​ $ 5.06 ​ ​ Forfeited (995,625) ​ $ 3.78 ​ ​ Cancelled ​ - ​ $ - ​ ​ ​ ​ ​ ​ Outstanding at December 31, 2020 16,746,238 ​ $ 2.71 ​ $ 6.71 ​ $ 10,866,320 Vested and expected to vest at December 31, 2020 ​ 16,746,238 ​ $ 2.71 ​ $ 6.71 ​ $ 10,866,320 Exercisable at December 31, 2020 9,381,854 ​ $ 2.35 ​ $ 5.17 ​ $ 9,964,551
Schedule of stock options outstanding	The following summarizes information about stock options that are outstanding at December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding Options Exercisable ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Weighted ​ ​ ​ ​ Weighted ​ Number Remaining ​ Average ​ Number ​ Average Range of Outstanding at Contractual ​ Exercise ​ Exercisable at ​ Exercise Exercise Prices December 31, 2020 Life in Years ​ Price ​ December 31, 2020 ​ Price $0.00 - $1.00 ​ 1,273,853 5.19 ​ $ 0.87 ​ 1,273,853 ​ $ 0.87 $1.01 - $2.00 ​ 4,982,929 4.39 ​ $ 1.50 ​ 4,912,929 ​ $ 1.50 $2.01 - $4.00 ​ 8,955,456 8.25 ​ $ 2.94 ​ 2,231,072 ​ $ 3.10 $4.01 - $7.00 ​ 1,329,000 6.40 ​ $ 6.61 ​ 759,000 ​ $ 6.50 $7.01 - $9.00 ​ 205,000 7.50 ​ $ 8.23 ​ 205,000 ​ $ 8.23 ​ ​ 16,746,238 6.71 ​ $ 2.71 ​ 9,381,854 ​ $ 2.35

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2020
INCOME TAXES
Schedule of domestic and foreign loss before income taxes	For financial reporting purposes, loss before income taxes includes the following components: ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) 2020 2019 United States ​ $ (40,626) ​ $ (28,957) PRC ​ (6,885) ​ (16,405) Total ​ $ (47,511) ​ $ (45,362)
Schedule of deferred income tax assets and liabilities	Significant components of the Company’s deferred income tax assets and liabilities as of December 31, 2020 and 2019 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (In thousands) 2020 2019 Deferred income tax assets: ​ ​ Net operating loss carryforwards ​ $ 78,790 ​ $ 94,828 Research and development credit carryforward ​ 6,244 ​ 7,740 Intangible assets ​ 8,049 ​ 5,733 Equity-based compensation ​ 4,436 ​ 5,423 Other ​ (2,533) ​ 396 Valuation allowance for deferred income tax assets ​ (94,986) ​ (114,120) Net deferred income tax assets ​ $ — ​ $ —
Schedule of reconciliation of provision for income taxes to the federal statutory rate	A reconciliation of the provision for income taxes to the federal statutory rate is as follows: ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) 2020 2019 Tax benefit at statutory rate ​ $ (9,977) ​ $ (9,526) State taxes ​ (732) ​ (1,701) Attribute expiration ​ 13,707 ​ 12,461 Nondeductible expenses ​ ​ 358 ​ ​ 453 Deemed royalty ​ ​ 4,220 ​ ​ — Other ​ (54) ​ (608) Change in applicable tax rates ​ 11,612 ​ (7) Change in valuation allowance ​ (19,134) ​ (1,072) ​ ​ $ — ​ $ —
Schedule of reconciliation of gross unrecognized tax benefits	A reconciliation of the beginning and ending amount of gross unrecognized tax benefits is as follows: ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) 2020 2019 Unrecognized tax benefits balance at January 1 ​ $ 2,581 ​ $ 2,986 Reductions for tax positions of prior periods ​ (499) ​ (405) Additions for tax positions of current period ​ — ​ — Unrecognized tax benefits balance at December 31 ​ $ 2,082 ​ $ 2,581

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	12 Months Ended
	Dec. 31, 2020
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of assets and liabilities measured at fair value on recurring and nonrecurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) ​ Fair Value at ​ ​ ​ ​ ​ ​ ​ ​ ​ Description December 31, 2020 Level 1 Level 2 Level 3 Investments in Current Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investments in common stock ​ $ 9,309 ​ $ 9,309 ​ $ — ​ $ — Investment in convertible loan-AFS ​ $ 83 ​ $ — ​ $ — ​ $ 83 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) Fair Value at ​ ​ ​ ​ ​ ​ ​ ​ ​ Description December 31, 2019 Level 1 Level 2 Level 3 Investments in Current Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment in common stock ​ $ 625 ​ $ 625 ​ $ — ​ $ —
Non-recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of quantitative information about level 3 fair value measurements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quantitative Information about Level 3 Fair Value Measurements ​ ​ (In Thousands) Fair Value at ​ ​ ​ ​ ​ ​ ​ September 29, 2020 ​ ​ ​ ​ ​ Description (remeasurement date) Valuation Techniques Unobservable Input Average/Median Investment in equity securities using measurement alternative ​ $ 12,872 Market comparable companies Multiples of selected comparable companies 5.3/1.1

DESCRIPTION OF BUSINESS (Detail

DESCRIPTION OF BUSINESS (Details)

Mar. 26, 2021USD ($)

Mar. 24, 2021$ / sharesshares

Jul. 24, 2020USD ($)shares

Oct. 29, 2019

Mar. 31, 2021shares

Nov. 30, 2020USD ($)

Sep. 30, 2020USD ($)

Sep. 30, 2020CNY (¥)

Jul. 31, 2020EUR (€)

Apr. 30, 2020USD ($)

Apr. 30, 2020CNY (¥)

Feb. 29, 2020USD ($)

Apr. 30, 2019USD ($)

Apr. 30, 2019EUR (€)

Mar. 31, 2019

Dec. 31, 2020USD ($)personsubsidiary

Dec. 31, 2020EUR (€)

Dec. 31, 2019USD ($)

Dec. 31, 2019EUR (€)

Nov. 20, 2020USD ($)

Aug. 27, 2020USD ($)

Aug. 27, 2020CNY (¥)

Jul. 31, 2020USD ($)

Nov. 30, 2019

Description of Business and Basis of Presentation

Number of subsidiaries | subsidiary

2

Term of lease contract

1 year

Assets held-for-sale

$ 0

$ 3,221,000

Accumulated deficit

(570,501,000)

(523,908,000)

Cash and cash equivalents

57,064,000

53,621,000

Shares issued under the offering | shares

23,000,000

Acquired in-process research and development

17,828,000

6,967,000

Revenues

15,141,000

4,131,000

Gross proceeds from the offering

$ 32,500,000

$ 43,700,000

Public offering price

150,000,000

$ 150,000,000

Loss on disposal of intangible assets

$ 450,000

$ 1,152,000

(408,000)

Subsequent Events

Description of Business and Basis of Presentation

Shares issued under the offering | shares

493,000

Gross proceeds from the offering

$ 32,500,000

Chairman And CEO

Description of Business and Basis of Presentation

Shares issued under the offering | shares

2,952,426

Pharmathen Global BV

Description of Business and Basis of Presentation

Upfront payment | €

€ 1,000,000

Non Royalty Exclusive Distribution Period

10 years

10 years

Non Royalty Exclusive Distribution, Supply Cost Determination, Period Considered

3 years

Additional Milestone Payments | €

€ 500,000

Milestone payment | €

1,000,000

Acquired in-process research and development

$ 1,700,000

€ 1,500,000

Black Belt Tx Limited

Description of Business and Basis of Presentation

Upfront payment | €

€ 5,000,000

Minimum equity financing

$ 5,900,000

Guokang Pharmaceuticals Co., Ltd

Description of Business and Basis of Presentation

Non Royalty Exclusive Distribution Period

3 years

Revenues

15,000,000

$ 4,100,000

Juventas Cell Therapy Ltd.

Description of Business and Basis of Presentation

Milestone payment

$ 10,000,000

¥ 70,000,000

BioInvent International AB

Description of Business and Basis of Presentation

Upfront payment

$ 5,900,000

Acquired in-process research and development

$ 5,900,000

Black Belt Tx Limited

Description of Business and Basis of Presentation

Upfront payment

$ 5,700,000

€ 5,000,000

Oppenheimer & Co. Inc. | Subsequent Events

Description of Business and Basis of Presentation

Offering price per share | $ / shares

$ 2.05

Option to purchase, term

30 days

Additional shares of common stock purchase | shares

15,853,658

Securities lock up period

90 days

Oppenheimer & Co. Inc. | Chairman And CEO | Subsequent Events

Description of Business and Basis of Presentation

Percentage of underwriters commission

1.00%

Oppenheimer & Co. Inc. | Investor | Subsequent Events

Description of Business and Basis of Presentation

Percentage of underwriters commission

6.00%

Minimum

Description of Business and Basis of Presentation

Number of hematology and oncology sales and marketing specialist | person

80

Maximum | Pharmathen Global BV

Description of Business and Basis of Presentation

Additional Milestone Payments | €

€ 2,000,000

Maximum | BioInvent International AB

Description of Business and Basis of Presentation

Potential Milestone payment and Royalty

$ 83,000,000

Maximum | Oppenheimer & Co. Inc. | Subsequent Events

Description of Business and Basis of Presentation

Additional shares of common stock purchase | shares

2,378,048

License Agreement Terms | Black Belt Tx Limited

Description of Business and Basis of Presentation

Upfront payment | €

€ 5,000,000

CASI China

Description of Business and Basis of Presentation

Cash

$ 4,500,000

CASI Wuxi

Description of Business and Basis of Presentation

Term of lease contract

50 years

Government grant received

$ 2,200,000

¥ 15,900,000

Construction project contract amount

$ 10,923,000

¥ 74,588,000

Cash

$ 19,500,000

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	Jan. 01, 2019USD ($)	Dec. 31, 2020USD ($)segmentshares	Dec. 31, 2019USD ($)shares
Percentage of ownership interest held by the parent entity in the non stock subsidiary		100.00%
Number of operating segments | segment		1
Impairment of property, plant and equipment		$ 0	$ 386,000
Impairment of Intangible Assets		1,537,000	0
Allowance for doubtful accounts		0	0
Right of use assets		8,696,000	8,708,000
Lease liability		$ 1,904,000	2,201,000
New accounting pronouncement or change in accounting principle	$ 140,000
Minimum
Estimated useful life		3 years
Maximum
Estimated useful life		5 years
Furniture and Equipment | Minimum
Estimated useful life		3 years
Furniture and Equipment | Maximum
Estimated useful life		5 years
CRGK
Accounts receivable		$ 4,600,000	$ 1,300,000
Accounting Standards Update 2016-02
Right of use assets	3,000,000
Lease liability	$ 3,200,000
CASI Wuxi
Percentage of ownership interest held by the parent entity in the non stock subsidiary		80.00%
Options
Antidilutive securities excluded from computation of earnings per share | shares		16,746,238	18,268,372
Warrant
Antidilutive securities excluded from computation of earnings per share | shares		8,271,709	9,843,720

INVESTMENT IN EQUITY SECURITI_3

INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS - Summary of Investments (Details) - Common Stock $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
MaxCyte Inc.
Gross unrealized gains equity securities at fair value	$ 2,729
Aggregate equity securities at fair value	2,729
BioInvent International AB
Cost	5,661
Gross unrealized gains equity securities at fair value	919
Aggregate equity securities at fair value	$ 6,580

INVESTMENT IN EQUITY SECURITI_4

INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS - Summary of Long-term investments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Long Term Investments
Total	$ 29,442	$ 14,038
Black Belt Tx Limited
Schedule Of Long Term Investments
Available-for-sale debt securities	83
Black Belt Tx Limited | Equity Securities
Schedule Of Long Term Investments
Equity securities without readily determinable fair value	2,250	2,250
Juventas Cell Therapy Ltd. | Equity Securities
Schedule Of Long Term Investments
Equity securities without readily determinable fair value	26,059	11,355
Juventas Cell Therapy Ltd. | Put option
Schedule Of Long Term Investments
Equity securities without readily determinable fair value	210	$ 433
BioInvent International AB | Warrants
Schedule Of Long Term Investments
Securities measured at fair value	$ 840

INVESTMENT IN EQUITY SECURITI_5

INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS (Details) kr in Millions	Sep. 29, 2020USD ($)	Sep. 29, 2020CNY (¥)	Oct. 31, 2020USD ($)shares	Sep. 30, 2020	Aug. 31, 2020USD ($)	Aug. 31, 2020CNY (¥)	Jul. 31, 2020USD ($)	Jul. 31, 2020EUR (€)	Jun. 30, 2020USD ($)	Jun. 30, 2020CNY (¥)	Jun. 30, 2019USD ($)	Jun. 30, 2019CNY (¥)	Apr. 30, 2019USD ($)	Apr. 30, 2019EUR (€)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Oct. 31, 2020SEK (kr)	Sep. 29, 2020CNY (¥)
Change in fair value of investment in equity securities															$ 3,200,000	$ (288,000)
BioInvent International AB
Investment to be made			$ 6,300,000														kr 53.8
Number of shares subscribed (in shares) | shares			1,200,000
Reverse stock split			25
Number of new warrants subscribed | shares			14,700,000
Number of shares subscribed per warrant			0.04														0.04
Subscription period for warrants			5 years
Fair value of warrants outstanding															$ 841,000
Warrants contractual life															4 years 10 months 28 days
BioInvent International AB | Volatility
Warrants , Measurement Input															0.4763
BioInvent International AB | Risk Free Interest Rate
Warrants , Measurement Input															0.0036
Juventas Cell Therapy Ltd.
Fair value of additional equity interest	$ 12,300,000																	¥ 83,700,000
Payments to acquire equity Investments											$ 11,788,000	¥ 80,000,000
Equity ownership (as a percent)				16.45%							16.327%	16.327%
Milestone payment | ¥		¥ 70,000,000
Interest rate (as a percent)				8.00%							8.00%	8.00%
Change in fair value of investment in equity securities															$ 1,116,000
Juventas Cell Therapy Ltd. | June 2020 Loan Agreement
Term of loan provided									1 year	1 year
Interest rate (as a percent)									20.00%	20.00%
Loans advanced to related party									$ 4,243,000	¥ 30,000,000
Interest income from related party															351,000
Juventas Cell Therapy Ltd. | August 2020 Loan Agreement
Term of loan provided					1 year	1 year
Interest rate (as a percent)					20.00%	20.00%
Loans advanced to related party					$ 5,790,000	¥ 40,000,000
Interest income from related party															375,000
Juventas Cell Therapy Ltd. | Put option
Payments to acquire equity Investments	$ 64,000	¥ 400,000
Black Belt Tx Limited
Payments to acquire equity Investments													$ 2,249,600	€ 2,000,000
Convertible Loan Trances							$ 83,000	€ 70,600
Minimum equity financing							$ 5,900,000
Percentage of price per share issued at which the outstanding principal loan is to be converted							80.00%	80.00%
Equity ownership (as a percent)													14.10%	14.10%
Interest rate (as a percent)							6.00%	6.00%
Term of loan							3 years	3 years
Loan to be advanced							$ 250,000	€ 211,800
Level 1 | MaxCyte Inc.
Fair value of additional equity interest															2,700,000	$ 600,000
Level 1 | BioInvent International AB
Fair value of additional equity interest															$ 6,600,000

INVENTORIES (Details)

INVENTORIES (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
INVENTORIES
Finished goods	$ 1,356,000	$ 4,514,000
Raw materials		28,000
Total	1,356,000	4,542,000
Inventory write down	$ 0	$ 152,000

LEASES - (Details)

LEASES - (Details) ¥ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2020USD ($)lease	Dec. 31, 2020USD ($)lease	Dec. 31, 2019USD ($)	Dec. 31, 2019CNY (¥)	Nov. 30, 2019m²
Number of Operating Leases | lease		7
Weighted average remaining lease term	38 years 4 months 13 days	38 years 4 months 13 days
Weighted average discount rates	3.72%	3.72%
Term of lease contract	1 year	1 year
Right of use assets	$ 8,696,000	$ 8,696,000	$ 8,708,000
Lease liability	1,904,000	1,904,000	2,201,000
Rent expenses		1,600,000	1,315,000
CHINA
Right of use assets	1,300,000	1,300,000
Lease liability	$ 1,200,000	$ 1,200,000
CHINA | Office Space Lease
Number of lease agreements | lease		2
Term of lease contract	3 years	3 years
Number of operating lease agreements terminated | lease	1
Gain (Loss) on termination of lease	$ 13,000
CHINA | Research And Development Facility Lease
Number of lease agreements | lease		1
Term of lease contract	5 years	5 years
CASI Wuxi
Term of lease contract					50 years
Land parcel area (in square meters) | m²					74,028.40
Prepaid lease payments for the land use right			$ 6,500,000	¥ 45

LEASES - Right of Use Assets an

LEASES - Right of Use Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Right of use assets	$ 8,696	$ 8,708
Operating Lease, Liability	$ 1,904	2,201
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent us-gaap:OtherLiabilitiesNoncurrent
Accrued liabilities
Operating Lease, Liability	$ 939	1,182
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent
Other liabilities
Operating Lease, Liability	$ 965	$ 1,019
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent

LEASES - Supplemental Cash Flow

LEASES - Supplemental Cash Flow (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows	$ 1,375	$ 1,315
Right of use assets obtained in exchange for lease obligations	$ 1,196	$ 2,157

LEASES - Future Undiscounted Ca

LEASES - Future Undiscounted Cash Flows (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
LEASES
2021	$ 1,052
2022	626
2023	280
Thereafter	42
Total	2,000
Discount factor	(96)
Lease liability	1,904	$ 2,201
Amounts due within 12 months	939
Non-current lease liability	$ 965

PROPERTY, PLANT AND EQUIPMENT_2

PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
PROPERTY, PLANT AND EQUIPMENT
Furniture and equipment	$ 1,622	$ 1,305
Leasehold improvements	985	792
Construction in progress	1,193
Total property, plant and equipment, gross	3,800	2,097
Accumulated depreciation and amortization	(1,322)	(726)
Impairment of property, plant and equipment	(416)	(386)
Total property, plant and equipment, net	$ 2,062	$ 985

PROPERTY, PLANT AND EQUIPMENT -

PROPERTY, PLANT AND EQUIPMENT - Additional Information (Details)	1 Months Ended		12 Months Ended
	Nov. 30, 2019CNY (¥)	Nov. 30, 2019USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Aug. 27, 2020CNY (¥)	Aug. 27, 2020USD ($)
Construction in Progress, Gross			$ 1,193,000
Depreciation and amortization expense			562,000	$ 603,000
Impairment of property, plant and equipment			$ 0	$ 386,000
Maximum
Estimated useful life			5 years
Minimum
Estimated useful life			3 years
CASI Wuxi
Land use right and property, plant and equipment, commitment amount	¥ 1,000,000,000	$ 143,000,000
Construction project contract amount					¥ 74,588,000	$ 10,923,000

INTANGIBLE ASSETS - Net Definit

INTANGIBLE ASSETS - Net Definite-lived Intangible Assets (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Finite-Lived Intangible Assets
Purchase Price	$ 16,029
Accumulated Amortization	(2,819)
ANDA
Finite-Lived Intangible Assets
Purchase Price	15,832
Accumulated Amortization	$ (2,721)
Estimated useful lives	13 years
Others
Finite-Lived Intangible Assets
Purchase Price	$ 197
Accumulated Amortization	$ (98)
Estimated useful lives	5 years

INTANGIBLE ASSETS - Changes in

INTANGIBLE ASSETS - Changes in intangible assets (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
INTANGIBLE ASSETS
Beginning balance	$ 13,674
Amortization expense	(1,289)
Foreign currency translation adjustment	825
Ending balance	$ 13,210

INTANGIBLE ASSETS - Expected Fu

INTANGIBLE ASSETS - Expected Future Amortization Expense (Details) $ in Thousands	Dec. 31, 2020USD ($)
INTANGIBLE ASSETS
2021	$ 1,321
2022	1,321
2023	1,321
2024	1,288
2025	1,288
2026 and thereafter	$ 6,671

INTANGIBLE ASSETS - Additional

INTANGIBLE ASSETS - Additional Information (Details)	1 Months Ended	12 Months Ended
	Feb. 29, 2020USD ($)item	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Finite-Lived Intangible Assets
Net book value		$ 13,210,000	$ 13,674,000
(Gain) loss on disposal of intangible assets	$ 450,000	$ 1,152,000	$ (408,000)
ANDA
Finite-Lived Intangible Assets
Estimated useful lives		13 years
Cloud Computing Arrangement
Finite-Lived Intangible Assets
Estimated useful lives		5 years
Chartwell | ANDA
Finite-Lived Intangible Assets
Number of intangible assets sold | item	7
Aggregate consideration on sale of intangible assets	$ 450,000
Net book value	0
Remaining consideration on sale of intangible assets	$ 1,000,000

ASSETS HELD FOR SALE - Addition

ASSETS HELD FOR SALE - Additional Information (Details)	1 Months Ended		3 Months Ended	12 Months Ended
	Jul. 31, 2020USD ($)item	Feb. 29, 2020USD ($)	Dec. 31, 2020USD ($)item	Dec. 31, 2020USD ($)item	Dec. 31, 2019USD ($)
Assets Held For Sale, Disclosure
(Gain) loss on disposal of intangible assets		$ 450,000		$ 1,152,000	$ (408,000)
Proceeds from disposal of intangible assets				$ 2,700,000	0
ANDA
Assets Held For Sale, Disclosure
Number of intangible assets classified as held for sale | item				14
Net book value	$ 1,250,000		$ 300,000	$ 300,000	$ 3,200,000
Impairment of assets held for sale				$ 1,500,000
(Gain) loss on disposal of intangible assets	$ 0		$ 700,000
Number of intangible assets sold | item	4		10
Proceeds from disposal of intangible assets	$ 1,250,000		$ 1,000,000

ASSETS HELD FOR SALE - Componen

ASSETS HELD FOR SALE - Components of assets held-for-sale (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets Held For Sale, Disclosure
Cost of intangible assets	$ 16,029
Accumulated Amortization	(2,819)
Total	$ 13,210	$ 13,674
Asset held for sale
Assets Held For Sale, Disclosure
Cost of intangible assets		4,074
Accumulated Amortization		(853)
Total		$ 3,221

GRANTS (Details)

GRANTS (Details) ¥ in Millions	1 Months Ended		12 Months Ended
	Apr. 30, 2020CNY (¥)	Apr. 30, 2020USD ($)	Dec. 31, 2020USD ($)	Nov. 30, 2019CNY (¥)	Nov. 30, 2019USD ($)
Grants, Disclosure [Line Items]
Term of lease contract			1 year
Other income			$ 35,000
CASI Wuxi
Grants, Disclosure [Line Items]
Term of lease contract				50 years	50 years
Government grant received	¥ 15.9	$ 2,200,000
Maximum | CASI Wuxi
Grants, Disclosure [Line Items]
Amount of grants eligible				¥ 25	$ 3,600,000

BANK BORROWINGS (Details)

BANK BORROWINGS (Details) ¥ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)	Dec. 31, 2020CNY (¥)	Dec. 31, 2020USD ($)	Nov. 03, 2020CNY (¥)	Nov. 03, 2020USD ($)	Apr. 27, 2020USD ($)
Bank Borrowings
Maximum Borrowing						$ 465,595
Interest expense	$ 3,100
China CITIC Bank Corporation Limited
Bank Borrowings
Maximum Borrowing				¥ 10	$ 1,500,000
Amount outstanding		¥ 5.4	$ 826,000
Interest rate		3.35%	3.35%
Interest expense	$ 1,000

NOTE PAYABLE (Details)

NOTE PAYABLE (Details) - USD ($)	Apr. 27, 2020	Dec. 31, 2020	Apr. 29, 2020
Notes Payable
Loan approved under Paycheck Protection Program (PPP)	$ 465,595
Interest expense		$ 3,100
M & T Bank
Notes Payable
Interest rate			1.00%
Term of loan	2 years

REDEEMABLE NONCONTROLLING INT_3

REDEEMABLE NONCONTROLLING INTEREST (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	May 31, 2019	Mar. 31, 2019	Dec. 31, 2020	Feb. 28, 2019	Dec. 26, 2018
Noncontrolling Interest
Value of transfer of selected ANDAs			$ 30
CASI Wuxi
Noncontrolling Interest
Equity ownership (as a percent)					80.00%
Investment commitment					$ 80
Initial cash investment				$ 21
Value of transfer of selected ANDAs	$ 30
Committed amount of cash payment within three years			$ 29
Call option purchase investment period			5 years
Payments to acquire investments		$ 20	$ 20
CASI Wuxi | Call Option
Noncontrolling Interest
Equity ownership (as a percent)		20.00%	20.00%
CASI Wuxi | Put option
Noncontrolling Interest
Equity ownership (as a percent)			20.00%
CASI Wuxi
Noncontrolling Interest
Payments to acquire investments			$ 20

REDEEMABLE NONCONTROLLING INT_4

REDEEMABLE NONCONTROLLING INTEREST - Changes in Redeemable Noncontrolling Interest (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
REDEEMABLE NONCONTROLLING INTEREST
Balance at beginning of period	$ 20,670	$ 0
Cash contribution by Wuxi LP	0	20,000
Share of CASI Wuxi net (loss)/income	(918)	(395)
Accretion of redeemable noncontrolling interest	1,694	1,065
Foreign currency translation adjustment	587
Balance at end of period	$ 22,033	$ 20,670

STOCKHOLDERS' EQUITY (Details)

STOCKHOLDERS' EQUITY (Details) - USD ($)	Mar. 26, 2021	Mar. 24, 2021	Jul. 24, 2020	Jul. 19, 2019	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Nov. 20, 2020
Remaining Dollar Amount Available Under Sales Agreement						$ 19,500,000
Public offering price						$ 150,000,000			$ 150,000,000
Shares issued under the offering			23,000,000
Gross proceeds from the offering	$ 32,500,000		$ 43,700,000
Common Stock, Shares Authorized						250,000,000	250,000,000
Treasury Stock, Shares						79,545	79,545
Preferred Stock, Shares Authorized						5,000,000	5,000,000
ETP Global Fund LP
Shares issued under the offering			1,200,000
Chairman And CEO
Shares issued under the offering			2,952,426
President
Shares issued under the offering			20,152
Sales Agreement
Net Proceeds From Issuance Of Common Stock								$ 475,000
Shares issued under the offering								143,248
Open Market Sale Agreement
Maximum Sales Price from Issuance of Common Stock				$ 30,000,000
Net Proceeds From Issuance Of Common Stock						$ 1,357,000	$ 182,000
Shares issued under the offering						434,000	59,000
Amendment To Open Sale Agreement
Maximum Sales Price from Issuance of Common Stock				$ 20,000,000
Subsequent Events
Net Proceeds From Issuance Of Common Stock					$ 1,539,000
Shares issued under the offering					493,000
Gross proceeds from the offering	$ 32,500,000
Subsequent Events | Open Market Sale Agreement
Remaining Dollar Amount Available Under Sales Agreement					$ 28,400,000
Subsequent Events | Oppenheimer & Co. Inc.
Offering price per share		$ 2.05
Option to purchase, term		30 days
Additional shares of common stock purchase		15,853,658
Securities lock up period		90 days
Subsequent Events | Oppenheimer & Co. Inc. | Maximum
Additional shares of common stock purchase		2,378,048
Subsequent Events | Oppenheimer & Co. Inc. | Chairman And CEO
Percentage of underwriters commission		1.00%
Subsequent Events | Oppenheimer & Co. Inc. | Investor
Percentage of underwriters commission		6.00%

STOCKHOLDERS' EQUITY - Warrants

STOCKHOLDERS' EQUITY - Warrants Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Number of Warrants
Beginning balance	9,843,720	11,781,825
Issued	0
Exercised	(82,304)	(1,938,105)
Expired	(1,489,707)
Ending balance	8,271,709	9,843,720
Exercisable	8,271,709
Weighted Average Exercise Price
Beginning balance	$ 4.43
Issued	0
Exercised	1.69	$ 1.69
Expired	3.75
Ending balance	4.58	$ 4.43
Exercisable	$ 4.58

NET LOSS PER SHARE (Details)

NET LOSS PER SHARE (Details) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Options
Antidilutive securities excluded from computation of earnings per share	16,746,238	18,268,372
Warrant
Antidilutive securities excluded from computation of earnings per share	8,271,709	9,843,720

NET LOSS PER SHARE - Basic and

NET LOSS PER SHARE - Basic and diluted net loss per share computation (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net loss attributable to CASI Pharmaceuticals, Inc.	$ (48,287)	$ (46,032)
Denominator:
Weighted average number of common shares	110,452	95,948
Denominator for basic and diluted net loss per share calculation	110,452	95,948
Net loss per share - basic and diluted (in dollars per share)	$ (0.44)	$ (0.48)

EMPLOYEE BENEFIT PLAN (Details)

EMPLOYEE BENEFIT PLAN (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
EMPLOYEE BENEFIT PLAN
Employer contributions	$ 250,000	$ 217,000
Defined contribution plan expenses	$ 1,542,000	$ 1,780,000

STOCK-BASED COMPENSATION - Comp

STOCK-BASED COMPENSATION - Compensation Expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7,821,000	$ 7,310,000
Research and Development Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	245,000	466,000
Sales and Marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	39,000
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7,537,000	$ 6,844,000

STOCK-BASED COMPENSATION - Weig

STOCK-BASED COMPENSATION - Weighted-Average Assumptions (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
STOCK-BASED COMPENSATION
Expected volatility	78.70%	77.30%
Range of expected volatility, Minimum	75.84%	75.50%
Range of expected volatility, Maximum	81.63%	84.48%
Range of risk free interest rate, Minimum	0.31%	1.62%
Range of risk free interest rate, Maximum	1.77%	2.59%
Expected term of option	6 years 1 month 6 days	6 years 18 days
Expected dividend yield	0.00%	0.00%

STOCK-BASED COMPENSATION - Opti

STOCK-BASED COMPENSATION - Options Outstanding (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding
Forfeited		(1,389,652)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price
Forfeited		$ 1.17
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures
Outstanding - Aggregate Intrinsic Value			$ 1,124,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding
Beginning Balance	18,268,372	18,429,308
Exercised	(2,789,473)	(599,002)
Granted	2,380,686	5,834,808
Expired	(117,722)	(7,090)
Forfeited	(995,625)
Cancelled		(4,000,000)
Ending Balance	16,746,238	18,268,372
Vested and expected to vest	16,746,238
Exercisable	9,381,854
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price
Beginning balance	$ 2.58	$ 2.44
Exercised	1.39	1.43
Granted	2.71	3.01
Expired	5.06	3.69
Forfeited	3.78
Cancelled		3.22
Ending Balance	2.71	$ 2.58
Vested and expected to vest	2.71
Exercisable	$ 2.35
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures
Weighted Average Remaining Contractual Term In Years	6 years 8 months 16 days
Vested and expected to vest - Weighted Average Remaining Contractual Term In Years	6 years 8 months 16 days
Exercisable - Weighted Average Remaining Contractual Term In Years	5 years 2 months 1 day
Outstanding - Aggregate Intrinsic Value	$ 10,866,320
Exercised - Aggregate Intrinsic Value	1,856,978
Vested and expected to vest - Aggregate Intrinsic Value	10,866,320
Exercisable - Aggregate Intrinsic Value	$ 9,964,551

STOCK-BASED COMPENSATION - Stoc

STOCK-BASED COMPENSATION - Stock Option Outstanding (Details)	12 Months Ended
	Dec. 31, 2020$ / sharesshares
Number Of Options Outstanding | shares	16,746,238
Number Of Options Outstanding Weighted Average Remaining Contractual Life in Years	6 years 8 months 15 days
Number Of Options Outstanding Weighted Average Exercise Price	$ 2.71
Number Of Options Exercisable | shares	9,381,854
Number Of Options Exercisable Weighted Average Exercise Price	$ 2.35
$0.00 - $1.00
Range of Exercise Prices Lower Range Limit	0
Range of Exercise Prices Upper Range Limit	$ 1
Number Of Options Outstanding | shares	1,273,853
Number Of Options Outstanding Weighted Average Remaining Contractual Life in Years	5 years 2 months 8 days
Number Of Options Outstanding Weighted Average Exercise Price	$ 0.87
Number Of Options Exercisable | shares	1,273,853
Number Of Options Exercisable Weighted Average Exercise Price	$ 0.87
$1.01 - $2.00
Range of Exercise Prices Lower Range Limit	1.01
Range of Exercise Prices Upper Range Limit	$ 2
Number Of Options Outstanding | shares	4,982,929
Number Of Options Outstanding Weighted Average Remaining Contractual Life in Years	4 years 4 months 20 days
Number Of Options Outstanding Weighted Average Exercise Price	$ 1.50
Number Of Options Exercisable | shares	4,912,929
Number Of Options Exercisable Weighted Average Exercise Price	$ 1.50
$2.01 - $4.00
Range of Exercise Prices Lower Range Limit	2.01
Range of Exercise Prices Upper Range Limit	$ 4
Number Of Options Outstanding | shares	8,955,456
Number Of Options Outstanding Weighted Average Remaining Contractual Life in Years	8 years 3 months
Number Of Options Outstanding Weighted Average Exercise Price	$ 2.94
Number Of Options Exercisable | shares	2,231,072
Number Of Options Exercisable Weighted Average Exercise Price	$ 3.10
$4.01 - $7.00
Range of Exercise Prices Lower Range Limit	4.01
Range of Exercise Prices Upper Range Limit	$ 7
Number Of Options Outstanding | shares	1,329,000
Number Of Options Outstanding Weighted Average Remaining Contractual Life in Years	6 years 4 months 24 days
Number Of Options Outstanding Weighted Average Exercise Price	$ 6.61
Number Of Options Exercisable | shares	759,000
Number Of Options Exercisable Weighted Average Exercise Price	$ 6.50
$7.01 - $9.00
Range of Exercise Prices Lower Range Limit	7.01
Range of Exercise Prices Upper Range Limit	$ 9
Number Of Options Outstanding | shares	205,000
Number Of Options Outstanding Weighted Average Remaining Contractual Life in Years	7 years 6 months
Number Of Options Outstanding Weighted Average Exercise Price	$ 8.23
Number Of Options Exercisable | shares	205,000
Number Of Options Exercisable Weighted Average Exercise Price	$ 8.23

STOCK-BASED COMPENSATION (Detai

STOCK-BASED COMPENSATION (Details) - USD ($)	1 Months Ended		12 Months Ended
	Apr. 30, 2019	Mar. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation			$ 7,821,000	$ 7,310,000
Performance Share Based Compensation Expense			$ 49,000	$ 73,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 1.85	$ 2.20
Share Based Payment Cash Received from Stock Option Exercises			$ 3,900,000	$ 854,000
Unrecognized Share Based Compensation Cost Expected To Be Recognized Over Weighted Average Period			$ 8,208,000
Unrecognized compensation cost is expected to be recognized over a weighted-average period (in years)			1 year 8 months 26 days
Executive Chairman
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number		1,000,000
Performance Based Option | Former Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cancelled Shares of Common Stock	4,000,000
Granted	4,000,000
Performance Based Option | Executive Chairman
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number		4,000,000
Time required to meet specific operational and strategic milestones in order for common stock shares issued to vest		18 months
Common stock exercise price	$ 2.85
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Granted Expire Terms			5 years
Long Term Incentive Plan 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			10,084,923
Long Term Incentive Plan 2011 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant					20,230,000
Long Term Incentive Plan 2011 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant					25,230,000

INCOME TAXES - Loss Before Inco

INCOME TAXES - Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
INCOME TAXES
United States	$ (40,626)	$ (28,957)
PRC	(6,885)	(16,405)
Total	$ (47,511)	$ (45,362)

INCOME TAXES - Deferred Income

INCOME TAXES - Deferred Income Tax Assets And Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred income tax assets:
Net operating loss carryforwards	$ 78,790	$ 94,828
Research and development credit carryforward	6,244	7,740
Intangible assets	8,049	5,733
Equity-based compensation	4,436	5,423
Other	(2,533)	396
Valuation allowance for deferred income tax assets	(94,986)	(114,120)
Net deferred income tax assets	$ 0	$ 0

INCOME TAXES - Reconciliation O

INCOME TAXES - Reconciliation Of The Provision For Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
INCOME TAXES
Tax benefit at statutory rate	$ (9,977)	$ (9,526)
State taxes	(732)	(1,701)
Attribute expiration	13,707	12,461
Nondeductible expenses	358	453
Deemed royalty	4,220
Other	(54)	(608)
Change in applicable tax rates	11,612	(7)
Change in valuation allowance	(19,134)	(1,072)
Total	$ 0	$ 0

INCOME TAXES - Gross Unrecogniz

INCOME TAXES - Gross Unrecognized Tax Benefits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
INCOME TAXES
Beginning balance	$ 2,581,000	$ 2,986,000
Reductions for tax positions of prior periods	(499,000)	(405,000)
Additions for tax positions of current period	0
Ending balance	$ 2,082,000	$ 2,581,000

INCOME TAXES (Details)

INCOME TAXES (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Contingency
Net reduction of unrecognized tax benefits	$ 499,000	$ 405,000
Operating loss carryforwards, tax	6,244,000
Unrecognized tax benefits	2,082,000	$ 2,581,000	$ 2,986,000
Domestic Tax Authority
Income Tax Contingency
Operating loss carryforwards	324,707,000
Foreign Tax Authority
Income Tax Contingency
Operating loss carryforwards	$ 13,464,000

FAIR VALUE MEASUREMENTS - Finan

FAIR VALUE MEASUREMENTS - Financial and Non-Financial Assets and Liabilities (Details) - USD ($)	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Long-lived assets		$ 1,550,000
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investment in common stock	$ 9,309,000		$ 625,000
Investment in convertible loan-AFS	83,000
Non-recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Long-lived assets			287,000
Level 1 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investment in common stock	9,309,000		625,000
Investment in convertible loan-AFS	0
Level 2 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investment in common stock	0		0
Investment in convertible loan-AFS	0
Level 3 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investment in common stock	0		$ 0
Investment in convertible loan-AFS	$ 83,000

FAIR VALUE MEASUREMENTS - Quant

FAIR VALUE MEASUREMENTS - Quantitative Information about Level 3 Fair Value Measurements (Details) - Non-recurring - Level 3 - Market comparable companies $ in Thousands	Sep. 29, 2020USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment in equity securities using measurement alternative, fair value	$ 12,872
Arithmetic Average [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment in equity securities using measurement alternative, measurement input	5.3
Median
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment in equity securities using measurement alternative, measurement input	1.1

FAIR VALUE MEASUREMENTS (Detail

FAIR VALUE MEASUREMENTS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Carrying amount			$ 3,087,000
Intangible assets and assets held for sale			$ 1,550,000
Impairment of equipment	$ 0	$ 386,000
Impairment of Intangible Assets	1,537,000	0
Leased equipment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Carrying amount		673,000
Impairment of equipment	0
Non-recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Intangible assets and assets held for sale		287,000
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Non-financial assets, measured at fair value	0	0
Non-financial liabilities, measured at fair value	$ 0	$ 0

RELATED PARTY TRANSACTIONS (Det

RELATED PARTY TRANSACTIONS (Details)	Jul. 01, 2019USD ($)	Jul. 01, 2019CNY (¥)	Jan. 31, 2020USD ($)	Jun. 30, 2019USD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Related Party Transaction
Term of lease contract						1 year
Inventory, Net						$ 1,356,000	$ 4,542,000
Spectrum
Related Party Transaction
Payable to related party							200,000
Expense incurred							2,600,000
Face amount							$ 1,500,000
Stated interest rate							0.50%
Equity ownership (as a percent)						6.80%
Spectrum | EVOMELA
Related Party Transaction
Related Party Transaction, Purchase Obligation Commitments								$ 9,200,000
Purchases from related party						$ 0	$ 7,800,000
BioCheck Inc.
Related Party Transaction
Term of lease contract				1 year
Lease payments			$ 12,000	$ 5,000	$ 63,000	$ 144,000	$ 60,000
Emerging Technology Partners LLC | Minimum
Related Party Transaction
Equity ownership (as a percent)						5.00%
Juventas Cell Therapy Ltd.
Related Party Transaction
Term of lease contract	1 year	1 year
Lease payments	$ 15,000	¥ 80,000
Lease income						$ 140,000
Future operating lease income						$ 70,000

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Details)	1 Months Ended		12 Months Ended
	Nov. 30, 2019CNY (¥)	Nov. 30, 2019USD ($)	Dec. 31, 2020USD ($)Milestone	Aug. 27, 2020CNY (¥)	Aug. 27, 2020USD ($)
CASI Wuxi
Land use right and property, plant and equipment, commitment amount	¥ 1,000,000,000	$ 143,000,000
Estimated construction period	3 years	3 years
Construction project contract amount				¥ 74,588,000	$ 10,923,000
BioInvent International AB
Number of milestones achieved			0
Black Belt Tx Limited
Number of milestones achieved			0
Pharmathen Global BV
number of milestone payments yet to be paid | $			1

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) $ / shares in Units, ¥ in Millions	Nov. 07, 2021USD ($)	Nov. 07, 2021CNY (¥)	Mar. 26, 2021USD ($)	Mar. 24, 2021$ / sharesshares	Feb. 03, 2021USD ($)	Feb. 03, 2021CNY (¥)	Jul. 24, 2020USD ($)	Mar. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2020CNY (¥)
Subsequent Event [Line Items]
Proceeds from bank borrowings									$ 783,000	$ 0
Gross proceeds from the offering			$ 32,500,000				$ 43,700,000
Subsequent Events
Subsequent Event [Line Items]
Gross proceeds from the offering			$ 32,500,000
Subsequent Events | Cleave Therapeutics, Inc
Subsequent Event [Line Items]
Upfront payment								$ 5,500,000
Milestone Payable								74,000,000
Investment in Convertible Note								$ 5,500,000
China CITIC Bank Corporation Limited
Subsequent Event [Line Items]
Amount outstanding									$ 826,000		¥ 5.4
Interest rate									3.35%		3.35%
China CITIC Bank Corporation Limited | Subsequent Events
Subsequent Event [Line Items]
Proceeds from bank borrowings	$ 500,000	¥ 3			$ 700,000	¥ 4.6
Interest rate	3.72%	3.72%			3.72%	3.72%
Oppenheimer & Co. Inc. | Subsequent Events
Subsequent Event [Line Items]
Offering price per share | $ / shares				$ 2.05
Option to purchase, term				30 days
Additional shares of common stock purchase | shares				15,853,658
Securities lock up period				90 days
Oppenheimer & Co. Inc. | Subsequent Events | Maximum
Subsequent Event [Line Items]
Additional shares of common stock purchase | shares				2,378,048
Investor | Oppenheimer & Co. Inc. | Subsequent Events
Subsequent Event [Line Items]
Percentage of underwriters commission				6.00%
Chairman And CEO | Oppenheimer & Co. Inc. | Subsequent Events
Subsequent Event [Line Items]
Percentage of underwriters commission				1.00%