X0306 4 2015-07-06 0 0001583648 PIERIS PHARMACEUTICALS, INC. PIRS 0001609405 Khuong Chau Quang C/O PIERIS PHARMACEUTICALS, INC. LISE-MEITNER-STRASSE 30 FREISING-WEIHENSTEPHAN 2M 85354 GERMANY 1 0 1 0 Common Stock 2015-07-06 4 P 0 495283 2.75 A 7194222 I See Footnotes Common Stock 2015-07-06 4 P 0 4717 2.75 A 65398 I See Footnotes These securities are held of record by OrbiMed Private Investments III, LP ("OPI III"). OrbiMed Capital GP III LLC ("GP III") is the sole general partner of OPI III, and OrbiMed Advisors LLC ("Advisors") is the managing member of GP III. Samuel D. Isaly, a natural person, is the managing member of and owner of a controlling interest in Advisors. By virtue of such relationships, GP III, Advisors and Mr. Isaly may be deemed to have voting and investment power over the securities held by OPI III and as a result may be deemed to have beneficial ownership over such securities. The Reporting Person is an employee of Advisors and is obligated to transfer any shares issued under equity grants made to him by the Issuer, or the economic benefits thereof, to Advisors for the ultimate benefit of OPI III. Each of GP III, Advisors, Mr. Isaly and the Reporting Person disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its or his pecuniary interest therein, if any. This report on Form 3 shall not be deemed an admission that any such entity or person, including the Reporting Person, is a beneficial owner of such securities for the purpose of Section 16 of the Exchange Act, or for any other purpose. These securities are held of record by OrbiMed Associates III, LP ("Associates III"). Advisors is the general partner of Associates III. Mr. Isaly is the managing member of and owner of a controlling interest in Advisors. By virtue of such relationships, Advisors and Mr. Isaly may be deemed to have voting and investment power over the securities held by Associates III and as a result may be deemed to have beneficial ownership over such securities. The Reporting Person is an employee of Advisors. /s/ Marc D. Mantell, Attorney-in-fact 2015-07-08