EX-4.1





 Exhibit 4.1 
  

					
	Number           	  		  	Shares
	  
 *PR
A-    *        
	  	Sierra Oncology, Inc.	  	*                *
			
	Incorporated Under the Laws of the State of Delaware	  		  	CUSIP 82640U 20 6
	  		  	  
 SEE REVERSE FOR CERTAIN DEFINITIONS

			
	This certifies that	  		  	
			
	Is the record holder of	  	*                    
(            )*	  	

 FULLY PAID AND NONASSESSABLE SHARES OF SERIES A PREFERRED STOCK $0.001 PAR VALUE PER SHARE, OF 

SIERRA ONCOLOGY, INC.            

 transferable on the books of the corporation in person or by duly authorized attorney upon surrender of this Certificate properly endorsed. This
Certificate is not valid until countersigned by the Transfer Agent and registered by the Registrar. 
 WITNESS the facsimile seal of the Corporation and the
facsimile signatures of its duly authorized officers. 
  

			
	Dated:                     	  	
		  	  

		  	Secretary
		
	COUNTERSIGNED AND REGISTERED:	  	
	AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC	  	  

	TRANSFER AGENT AND REGISTRAR	  	President

  

			
	By:	 	  

		 	Authorized Signature













 The Corporation shall furnish without charge to each stockholder who so requests a statement
of the powers, designations, preferences and relative, participating, optional or other special rights of each class of stock of the Corporation or series thereof and the qualifications, limitations or restrictions of such preferences and/or rights.
Such requests shall be made to the Corporation’s Secretary at the principal office of the Corporation. 
 KEEP THIS CERTIFICATE IN A
SAFE PLACE. IF IT IS LOST, STOLEN, OR DESTROYED THE CORPORATION WILL REQUIRE A BOND INDEMNITY AS A CONDITION TO THE ISSUANCE OF A REPLACEMENT CERTIFICATE. 

The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out
in full according to applicable laws or regulations: 
  

													
	TEN COM	 	–	 	as tenants in common	    	UNIF GIFT MIN ACT	 	-	 	                            	 	CUST                                     
       
	TEN ENT	 	–	 	as tenants by the entireties	    		 		 	        (CUST)	 	(Minor)
	JT TEN	 	–	 	as joint tenants with right of survivorship and not as tenants in common	    	under Uniform Gifts to Minors Act	 		 	
                          
                                         
                         

(State)

	COM PROP	 	–	 	as community property	    	UNIF TRF MIN ACT	 	-	 	                            
        (CUST)	 	Custodian (until age                       )
							
		 		 		    		 		 	                                	 	Under Uniform Transfers
		 		 		    		 		 	 (Minor)

    to Minors Act     
	 	                                     
                   
		 		 		    		 		 		 	                    (State)


Additional abbreviations may also be used though not in the above list. 

FOR VALUE RECEIVED,
                                         
                                        hereby
sell(s), assign(s) and transfer(s) unto 
 PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE 

 

 

   

 
 (PLEASE PRINT OR TYPEWRITE NAME AND
ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE) 

                          
                                         
                                         
                                         
                                         
                           shares of the capital stock represented by within Certificate, and do hereby irrevocably
constitute and appoint 

                          
                                         
                                         
                                         
                                         
       attorney-in-fact to transfer the said stock on the books of the within named Corporation with full power of the substitution in
the premises. 
  

											
	Dated	 	                    	 		 		 		 	
					
		 		 		 	X  	 	  

					
		 		 		 	X	 	  

	Signature(s) Guaranteed:	 	 	 		 	NOTICE:        	 	THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATSOEVER.
	By	 	
                     

	 		 		 		 	
	THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION, (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM),
PURSUANT TO S.E.C. RULE 17Ad-15. GUARANTEES BY A NOTARY PUBLIC ARE NOT ACCEPTABLE. SIGNATURE GUARANTEES MUST NOT BE DATED.