Exhibit 99.1

SPECIAL MEETING OF STOCKHOLDERS OFCASI PHARMACEUTICALS, INC. , 2023 IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALSFOR THE STOCKHOLDER MEETING TO BE HELD ON , 2023.You may obtain a copy of the related proxy statement, the accompanying Notice of Special Meeting of Stockholders, and the form of proxy card without charge by visiting www.casipharmaceuticals.com Please sign, date and mailyour proxy card in theenvelope provided as soonas possible.Signature of Stockholder Date: Signature of Stockholder Date: Note:PleasesignexactlyasyournameornamesappearonthisProxy.Whensharesareheldjointly,eachholdershouldsign.Whensigningasexecutor,administrator,attorney,trusteeorguardian,pleasegivefull title as such. If the signer is a corporation, please sign full corporate name by duly authorized officer, giving full title as such. If signer is a partnership, please sign in partnership name by authorized person. To change the address on your account, please check the box at right andindicate your new address in the address space above. Please note thatchanges to the registered name(s) on the account may not be submitted viathis method. 1. TheMergerProposal- to approve and adopt the agreement and plan ofmerger (the “Merger Agreement”) by and between the Company and CASI Pharmaceuticals Holdings, Inc., an exempted company incorporated under the laws of the Cayman Islands and a wholly-owned subsidiary of the Company (“CASI Cayman”), which includes a plan of merger required to be filed with the Registrar of Companies of the Cayman Islands, substantially in the form as attached as Annex A to the Merger Agreement (the “Plan of Merger”), pursuant to which the Company will merge with and into CASI Cayman, with CASI Cayman as the surviving company upon the merger becoming effective, and whereby each issued and outstanding share of the common stock of the Company will be converted into the right to receive one ordinary share, par value US$0.0001 each, of CASI Cayman credited as fully paid (the “Redomicile Merger”); and 1.2. The Adjournment Proposal - to consider and vote on any proposal toadjourn the Special Meeting, from time to time, to a later date or dates, ifnecessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement and the Redomicile Merger at the time of the Special Meeting.The shares of Common Stock represented by this proxy will be voted as directed. If no contraryinstructionisgiven,thesharesofCommonStockwillbevotedforthemerger proposalandtheadjournmentproposal.Intheirdiscretion,theproxiesareauthorizedtovote uponsuchotherbusinessasmayproperlycomebeforethemeetingoranyadjournmentsor postponementsthereof.Attendanceoftheundersignedatthemeetingoratanyadjournment orpostponementthereofwillnotbedeemedtorevokethisproxyunlesstheundersigned shallrevokethisproxyinwritingorshalldeliverasubsequentlydatedproxytotheCorporate SecretaryofCASIPharmaceuticals,Inc.orshallvoteinpersonatthemeeting. THIS PROXY IS SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS OF CASI PHARMACEUTICALS, INC. (THE "COMPANY").THE BOARD OF DIRECTORS RECOMMENDS A VOTE "FOR" PROPOSALS 1 AND 2.PLEASE SIGN, DATE AND RETURN PROMPTLY IN THE ENCLOSED ENVELOPE. PLEASE MARK YOUR VOTE IN BLUE OR BLACK INK AS SHOWN HERE x Please detach and mail in the envelope provided. ------------------ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .---------------- FORAGAINSTABSTAINGO GREENe-Consent makes it easy to go paperless. With e-Consent, you can quickly access your proxymaterial, statements and other eligible documents online, while reducing costs, clutter and paper waste. Enroll today via www.astfinancial.com to enjoy online access. 00030000030000000000 8032423

0------------------ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .---------------- 14475CASI PHARMACEUTICALS, INC.SPECIAL MEETING OF STOCKHOLDERSTHIS PROXY IS SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS The undersigned hereby appoints Rui Zhang and Alexander Zukiwski, MD and each of them as proxy (each of whom shall have full power of substitution) to represent the undersigned at the Special Meeting of Stockholders to be held at the ____________ on _________ at 9:00 a.m. and at any adjournment or postponement thereof, and to vote the shares of common stock the undersigned would be entitled to vote if personally present, as indicated on the reverse. (Continued and to be signed on the reverse side) 1.1