Exhibit 4.3

THIS CERTIFIES THAT NUMBER CERT.9999 **9.000.000.000***** ***9.000.000,000**** ****9,000,000,000*** *****9.000,000,000"* ******9.000.000.000* is the registered owner of ' ·-: ,:)v,::i:i:.,:::J::"" ' '"'NINBBILL..IONJAND00/100 * :l,J:JC, 1GJ,!)l)ll" • .......,,J,)C,,;t)C:,,;t;•)• • • :"? H'<,(;(..(!, l!C!G , LU.:'""' £C.I:"1;·;N • • C.::".R.'J.·)•;!).J ... t IH ; 3l'..1i h ANr'\ 0 );.1.'\. l-..:. .:;.,:, r1;, ;nrr:: .... .r,r, :,, d(•r ,..,rr, ... ... · ....c,c r rJ,f.'r':·,r•·r" ··; •. <.. ,OC'i.,f:i 'D,C·C•(;"'·-,... N•...-,.t,Y Cl, 2CC':i"' . ...a. ..,._.a.J.. : 1 ..JJJ 1 VUU 1 C.J0-- ,·..., .,·.lt.:. :--'" .t. l:!·:•..\. \; ;t; - :·, 1 t-a:. B LI.I ; l l\.!."JP Gl"'/ltlt .., ,!.?•. - .a.•··:,:;l; ,\1-,.tJ.vv··..' .......... "··•<1,G P. 100 , '1CP'1 "."'"'"'... .--", t1 "),000,!f'tr) 4·"" ... " A,· ............. ,nn.D,000,!')0 ............. ..: ....C..".. ,r:r;'3,f)!")Q,:YC.:f)-.· ......... c-..... • ,i)r (1l1/''.i •• \.·.: t..,::....·:,!, , (loc.., ... , :,...·. ·, ·l t•,t c cj;; .... : ., o,'}i)l),lJiJl)"' , , -:Fz=-:Jr·E!J ... \-.-_.-·.,·:T . .::.; ::; 't4i! ..n,-!-.. ,:tt,r· ., .... !i,c.r Ci,L ( FULLY PAID AND NON-ASSESSABLE COMMON SHARES IN THE CAPITAL OF MEDICENNA THERAPEUTICS CORP. transferable only on the books of the Corporation by the registered holder in person or by duly authorized Attorney on surrender of this Certificate properly endorsed. This Certificate is not valid until countersigned and registered by the Transfer Agent and Registrar of the Corporation. IN WITNESS WHEREOF the Corporation has caused this Certificate to be signed by its duly authorized officers. - -::::-COUNTERSIGNED by Continental Stock Transfer & Trust Co. 1 State Street, 30th Floor New York, NY 10004 Co-Transfer Agent ( ;; AUTHORIZED OFFICER 6215559

RESTRICTIONS FOR VALUE RECEIVED, hereby sell, assign and transfer unto PLEASE INSERT SOCIAL INSURANCE NUMBER OF TRANSFEREE (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS OF ASSIGNEE) Shares of the CapitalStock represented by the within Certificate,and do hereby irrevocably constitute and appol Attorney to transfer the said S1ock on the Books of the within named Corporation, with full power of substitution in the premises. Dated: Signature: _ w (.) z w en NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITIEN UPON THE FACE OF THE CERTIFICATE, IN EVERY PARTICULAR, WTI HOUT ALTERATION OR ENLARGEMENT,OR ANY CHANGE WHATSOEVER,AND MUST BE GUARANTEED BY A SCHEDULE 1 CANADIAN CHARTERED BANK OR AN ELIGIBLE GUARANTOR INSTITUTION WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM. ·aW: ll. Guaranteed by_:. 111111111111111111111111111111111111 IIII 999999 11111111111111111111111W1l11l11111 CERT.9999 111111111111111111111111111111111111111111111 TIR5405 .. ' • - l • J