UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549



FORM 10-Q/A



(Amendment No. 1)



|x | QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ----------------------------------------------------------------------------------------



For the quarterly period ended September 30, 2014



| ̈ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | -----------------------------------------------------------------------------------------



For the transition period from ___________ to _____________.



Commission file number0-20713



CASI PHARMACEUTICALS, INC.

(Exact name of registrant as specified in
its charter)



|Delaware                        | 58-1959440                          
|------------------------------- | ------------------------------------
|(State or other jurisdiction of | (I.R.S. Employer Identification No.)
|incorporation or organization)  |                                     



9620 Medical Center Drive, Suite 300

Rockville, Maryland

(Address of principal executive offices)



20850

(Zip code)



(240) 864-2600

(Registrant’s telephone number, including
area code)



(Former name, former
address and former fiscal year, if changed since last report)



Indicate by check mark whether the registrant
(1) has filed all reports required to be filed by Section 13 or 15 (d) of the Securities Exchange Act of 1934 during the preceding
12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.



YES x NO  ̈



Indicate by check mark whether the registrant
has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted
and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant
was required to submit and post such files).



YES x NO  ̈



Indicate by check mark whether the registrant is a large accelerated
filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated
filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.
(Check one):



|Large accelerated filer  ̈ | Accelerated filer  ̈ | Non-accelerated filer  ̈ | Smaller reporting company þ
|------------------------- | ------------------- | ----------------------- | ---------------------------



Indicate by checkmark whether the registrant is a shell company
(as defined in Rule 12b-2 of the Exchange Act).



YES  ̈ NO
x



Indicate the number of shares outstanding
of each of the issuer’s classes of common stock, as of the most recent practicable date.



|Class                       |  | Outstanding at November 7, 2014
|--------------------------- |  | -------------------------------
|Common Stock $.01 Par Value |  | 32,445,811                     













Explanatory Note



CASI Pharmaceuticals, Inc. (the “Company”) is filing
this Amendment No. 1 (this “Amendment”)  to its Quarterly Report on Form 10-Q filed with the Securities and
Exchange Commission (the “Commission”) on November 14, 2014 for the quarterly period ended September 30, 2014 (the
“Original Report”) solely to refile Exhibits 10.3, 10.4 and 10.5 (the “Exhibits”) to the Original Report
with revised redactions in response to comments received from the Commission regarding a confidential treatment request submitted
to the Commission with respect to the Exhibits.



This Amendment is an exhibit-only filing. No other changes have
been made to the Original Report. This Amendment speaks as of the original filing date of the Original Report and does not reflect
any events that occurred at a date subsequent to the filing of the Original Report or modify or update those disclosures therein
in any way. Accordingly, this Amendment should be read in conjunction with the Company’s filings made with the Commission
subsequent to the filing of the Original Report.











PART II - OTHER INFORMATION



ITEM 6. EXHIBITS



|4.1   |  | Certificate of Designation of Series A Preferred Stock (incorporated by reference to Exhibit 4.1 to the Company’s Current Report on Form 8-K filed on September 19, 2014)                                                                                                                                                                                                                                                                                                                                                                                                              
|----- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|4.2   |  | Secured Promissory Note, dated as of September 17, 2014, issued
        to Talon Therapeutics, Inc. (incorporated by reference to Exhibit 4.2 to the Company’s Current Report on Form 8-K filed on
        September 19, 2014)                                                                                                                                                                                                                                                                                                                                                         
|10.1  |  | Investment Agreement, dated as of September 17, 2014, by and
        between the Company and Spectrum Pharmaceuticals, Inc. (incorporated by reference to Exhibit 10.1 to the Company’s Current
        Report on Form 8-K filed on September 19, 2014)                                                                                                                                                                                                                                                                                                                                
|10.2  |  | Investment Agreement, dated as of September 17, 2014, by and
        between the Company and Spectrum Pharmaceuticals Cayman, L.P. (incorporated by reference to Exhibit 10.2 to the Company’s
        Current Report on Form 8-K filed on September 19, 2014)                                                                                                                                                                                                                                                                                                                         
|10.3† |  | License Agreement, dated as of September 17, 2014, by and between the Company and Spectrum Pharmaceuticals, Inc. (filed herewith)                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|10.4† |  | License Agreement, dated as of September 17, 2014, by and between
        the Company and Spectrum Pharmaceuticals Cayman, L.P. (filed herewith)                                                                                                                                                                                                                                                                                                                                                                                                                                       
|10.5† |  | License Agreement, dated as of September 17, 2014, by and between
        the Company and Talon Therapeutics, Inc. (filed herewith)                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|31.1  |  | Rule 13a-14(a) Certification of Chief Executive Officer                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|31.2  |  | Rule 13a-14(a) Certification of Principal Accounting Officer                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|32.1* |  | Section 1350 Certification of Chief Executive Officer                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|32.2* |  | Section 1350 Certification of Principal Accounting Officer                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
|101*  |  | The following financial information from the Registrant’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2014, formatted in eXtensible Business Reporting Language (XBRL):  (i) Unaudited Consolidated Balance Sheets at September 30, 2014 and December 31, 2013, (ii) Unaudited Consolidated Statements of Operations for the Three and Nine months ended September 30, 2014 and 2013, (iii) Unaudited Consolidated Statements of Cash Flows for the Nine months ended September 30, 2014 and 2013 and (iv) Notes to Unaudited Consolidated Financial Statements.*



* Previously filed with the Company’s Quarterly Report
on 10-Q for the quarter ended September 30, 2014 as filed on November 14, 2014.



†Portions of this exhibit (indicated by asterisks) have
been omitted pursuant to a request for confidential treatment submitted to the SEC.











SIGNATURES



Pursuant to the requirements of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.



|                       | CASI PHARMACEUTICALS, INC.  
|---------------------- | ----------------------------
|                       | (Registrant)                
|                       |                             
|                       |                             
|Date: January 21, 2015 | /s/ Ken K. Ren              
|                       | Ken K. Ren                  
|                       | Chief Executive Officer     
|                       |                             
|                       |                             
|Date: January 21, 2015 | /s/ Sara B. Capitelli       
|                       | Sara B. Capitelli           
|                       | Principal Accounting Officer











EXHIBIT INDEX



|4.1   |  | Certificate of Designation of Series A Preferred Stock (incorporated by reference to Exhibit 4.1 to the Company’s Current Report on Form 8-K filed on September 19, 2014)                                                                                                                                                                                                                                                                                                                                                                                                              
|----- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|4.2   |  | Secured Promissory Note, dated as of September 17, 2014, issued
        to Talon Therapeutics, Inc. (incorporated by reference to Exhibit 4.2 to the Company’s Current Report on Form 8-K filed on
        September 19, 2014)                                                                                                                                                                                                                                                                                                                                                         
|10.1  |  | Investment Agreement, dated as of September 17, 2014, by and
        between the Company and Spectrum Pharmaceuticals, Inc. (incorporated by reference to Exhibit 10.1 to the Company’s Current
        Report on Form 8-K filed on September 19, 2014)                                                                                                                                                                                                                                                                                                                                
|10.2  |  | Investment Agreement, dated as of September 17, 2014, by and
        between the Company and Spectrum Pharmaceuticals Cayman, L.P. (incorporated by reference to Exhibit 10.2 to the Company’s
        Current Report on Form 8-K filed on September 19, 2014)                                                                                                                                                                                                                                                                                                                         
|10.3† |  | License Agreement, dated as of September 17, 2014, by and between the Company and Spectrum Pharmaceuticals, Inc. (filed herewith)                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|10.4† |  | License Agreement, dated as of September 17, 2014, by and between
        the Company and Spectrum Pharmaceuticals Cayman, L.P. (filed herewith)                                                                                                                                                                                                                                                                                                                                                                                                                                       
|10.5† |  | License Agreement, dated as of September 17, 2014, by and between
        the Company and Talon Therapeutics, Inc. (filed herewith)                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|31.1  |  | Rule 13a-14(a) Certification of Chief Executive Officer                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|31.2  |  | Rule 13a-14(a) Certification of Principal Accounting Officer                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|32.1* |  | Section 1350 Certification of Chief Executive Officer                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|32.2* |  | Section 1350 Certification of Principal Accounting Officer                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
|101*  |  | The following financial information from the Registrant’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2014, formatted in eXtensible Business Reporting Language (XBRL):  (i) Unaudited Consolidated Balance Sheets at September 30, 2014 and December 31, 2013, (ii) Unaudited Consolidated Statements of Operations for the Three and Nine months ended September 30, 2014 and 2013, (iii) Unaudited Consolidated Statements of Cash Flows for the Nine months ended September 30, 2014 and 2013 and (iv) Notes to Unaudited Consolidated Financial Statements.*



* Previously filed with the Company’s Quarterly Report
on 10-Q for the quarter ended September 30, 2014 as filed on November 14, 2014.



†Portions of this exhibit (indicated by asterisks) have
been omitted pursuant to a request for confidential treatment submitted to the SEC.