EXHIBIT A

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, the undersigned agree to the joint filing on behalf of each of them of a statement on Schedule 13G (including amendments thereto) with respect to the Common Stock of Conatus Pharmaceuticals, Inc. and further agree that this agreement be included as an exhibit to such filing. Each party to the agreement expressly authorizes each other party to file on its behalf any and all amendments to such statement. Each party to this agreement agrees that this joint filing agreement may be signed in counterparts.

In evidence whereof, the undersigned have caused this Agreement to be executed on their behalf this 5th day of February, 2018.

 

MPM BIOVENTURES IV-QP, L.P.      MPM BIOVENTURES IV GMBH & CO. BETEILIGUNGS KG

By:

  MPM BioVentures IV GP LLC,     

By:

   MPM BioVentures IV GP LLC,
  its General Partner                  in its capacity as the Managing Limited Partner
By:   MPM BioVentures IV LLC,      By:    MPM BioVentures IV LLC,
  its Managing Member         its Managing Member
By:  

/s/ Luke Evin

     By:   

/s/ Luke Evin    

  Name: Luke Evnin         Name: Luke Evnin
  Title: Member         Title: Member
         
MPM ASSET MANAGEMENT INVESTORS BV4 LLC      MPM BIOVENTURES V, L.P.
By:   MPM BioVentures IV LLC     

By:

   MPM BioVentures V GP LLC,
  its Manager         its General Partner
By:  

/s/ Luke Evin

     By:    MPM BioVentures V LLC,
  Name: Luke Evnin         its Managing Member
  Title: Member        
       By:   

/s/ Luke Evin

          Name: Luke Evnin
          Title: Member
MPM ASSET MANAGEMENT INVESTORS BV5 LLC      MPM BIOVENTURES IV GP LLC
By:   MPM BioVentures IV LLC      By:    MPM BioVentures IV LLC,
  its Manager         its Managing Member
By:  

/s/ Luke Evin

     By:   

/s/ Luke Evin

  Name: Luke Evnin         Name: Luke Evnin
  Title: Member         Title: Member
MPM BIOVENTURES IV LLC        
By:  

/s/ Luke Evin

       
  Name: Luke Evnin        
  Title: Member        

 

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MPM BIOVENTURES V GP LLC      MPM BIOVENTURES V LLC
By:   MPM BioVentures V LLC,      By:   

/s/ Luke Evin

  its Managing Member               Name:    Luke Evnin
       Title:    Member
By:  

/s/ Luke Evin

       
Name:   Luke Evnin        
Title:   Member        
MPM BIO 2014 NVS STRATEGIC FUND, L.P.      MPM BIOVENTURES 2014 NVS STRATEGIC FUND GP LLC
By:   MPM BioVentures 2014 NVS Strategic Fund GP LLC,      By:    MPM BioVentures 2014 LLC,
  its General Partner                  its Managing Member
By:   MPM BioVentures 2014 LLC,        
  its Managing Member      By:   

/s/ Luke Evin

 

By:

 

 

/s/ Luke Evin

    

Name:

Title:

  

Luke Evnin

Managing Director

Name:   Luke Evnin        
Title:   Managing Director        
MPM BIOVENTURES 2014 LLC     

 

By:

 

 

/s/ Luke Evin

       
Name:   Luke Evnin        
Title:   Managing Director        

 

By:

 

 

/s/ Luke Evin

    

 

By:

  

 

/s/ Ansbert Gadicke

  Name: Luke Evnin         Name: Ansbert Gadicke

 

By:

 

 

/s/ Todd Foley

       
  Name: Todd Foley        

 

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