X0306 4 2014-07-15 0 0001135906 EPIRUS Biopharmaceuticals, Inc. EPRS 0001495741 TPG Group Holdings (SBS) Advisors, Inc. C/O TPG GLOBAL, LLC 301 COMMERCE STREET, SUITE 3300 FORT WORTH, TX 76102 0 0 1 0 0000860866 BONDERMAN DAVID C/O TPG GLOBAL, LLC 301 COMMERCE STREET, SUITE 3300 FORT WORTH, TX 76102 0 0 1 0 0001099776 COULTER JAMES G C/O TPG GLOBAL, LLC 301 COMMERCE STREET, SUITE 3300 FORT WORTH, TX 76102 0 0 1 0 Common Stock 2014-07-15 4 J 0 22239223 A 22239223 I See Explanation of Responses David Bonderman and James G. Coulter are officers and sole shareholders of TPG Group Holdings (SBS) Advisors, Inc. ("Group Advisors" and, together with Messrs. Bonderman and Coulter, the "Reporting Persons"), which is the general partner of TPG Group Holdings (SBS), L.P., which is the sole member of TPG Holdings I-A, LLC, which is the general partner of TPG Holdings I, L.P., which is the sole member of TPG Biotechnology GenPar III Advisors, LLC, which is the general partner of TPG Biotechnology GenPar III, L.P., which is the general partner of TPG Biotechnology Partners III, L.P. ("TPG Biotech III"), which directly holds 22,239,223 shares of Common Stock ("Common Stock") of EPIRUS Biopharmaceuticals, Inc. (the "Issuer"). On July 15, 2014, TPG Biotech III received 22,239,223 shares of Common Stock in exchange for certain securities of the company formerly known as EPIRUS Biopharmaceuticals, Inc. (the "Former Entity") in connection with the merger of the Former Entity into the Issuer. Because of the relationship between the Reporting Persons and TPG Biotech III, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of the greater of their respective direct or indirect pecuniary interests in the profits or capital accounts of TPG Biotech III. Each of TPG Biotech III and each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of TPG Biotech III's or such Reporting Person's pecuniary interest therein, if any. Pursuant to Rule 16a-1(a)(4) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests. (5) The Reporting Persons are jointly filing this Form 4 pursuant to Rule 16a-3(j) under the Exchange Act. (6) Ronald Cami is signing on behalf of both Messrs. Bonderman and Coulter pursuant to authorization and designation letters dated July 1, 2013, which were previously filed with the Securities and Exchange Commission. /s/ Ronald Cami, Vice President, TPG Group Holdings (SBS) Advisors, Inc. (5) 2014-07-17 /s/ Ronald Cami, on behalf of David Bonderman (5) (6) 2014-07-17 /s/ Ronald Cami, on behalf of James G. Coulter (5) (6) 2014-07-17