Exhibit A
Joint Filing Statement
I, the undersigned, hereby express my agreement that the attached Schedule 13D (and any amendments thereto) relating to the beneficial ownership by the undersigned of the equity securities of Aratana Therapeutics, Inc. is filed on behalf of each of the undersigned.
| Date: March 13, 2014 | ||
| MPM BIOVENTURES V GP LLC | ||
| By: | MPM BioVentures V LLC, | |
| its Managing Member | ||
| By: | /s/ Ansbert Gadicke | |
| Name: | Ansbert Gadicke | |
| Title: | Member | |
| MPM BIOVENTURES V LLC | ||
| By: | /s/ Ansbert Gadicke | |
| Name: | Ansbert Gadicke | |
| Title: | Member | |
| MPM BIOVENTURES V, L.P. | ||
| By: | MPM BioVentures V GP LLC, its General Partner | |
| By: | MPM BioVentures V LLC, its Managing Member | |
| By: | /s/ Ansbert Gadicke | |
| Name: | Ansbert Gadicke | |
| Title: | Member | |
| MPM ASSET MANAGEMENT INVESTORS BV5 LLC | ||
| By: | MPM BioVentures V LLC | |
| Its: Manager | ||
| By: | /s/ Ansbert Gadicke | |
| Name: | Ansbert Gadicke | |
| Title: | Member | |
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| MPM CAPITAL LLC | ||
| By: | Medical Portfolio Management LLC, | |
| its Managing Member | ||
| By: | /s/ Ansbert Gadicke | |
| Name: | Ansbert Gadicke | |
| Title: | Member | |
| MEDICAL PORTFOLIO MANAGEMENT LLC | ||
| By: | /s/ Ansbert Gadicke | |
| Name: | Ansbert Gadicke | |
| Title: | Member | |
| By: | /s/ Ansbert Gadicke | |
| Name: | Ansbert Gadicke | |
| By: | /s/ Luke Evnin | |
| Name: | Luke Evnin | |
| By: | /s/ Todd Foley | |
| Name: | Todd Foley | |
| By: | /s/ James Paul Scopa | |
| Name: | James Paul Scopa | |
| By: | /s/ Vaughn M. Kailian | |
| Name: | Vaughn M. Kailian | |
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