X0306 4 2018-06-20 0 0000861838 IDERA PHARMACEUTICALS, INC. IDRA 0001263508 BAKER BROS. ADVISORS LP 860 WASHINGTON STREET 3RD FLOOR NEW YORK NY 10014 1 0 1 0 0001551138 14159, L.P. 860 WASHINGTON STREET, 3RD FLOOR NEW YORK NY 10014 1 0 1 0 0001551139 667, L.P. 860 WASHINGTON STREET, 3RD FLOOR NEW YORK NY 10014 1 0 1 0 0001580575 Baker Bros. Advisors (GP) LLC 860 WASHINGTON STREET 3RD FLOOR NEW YORK NY 10014 1 0 1 0 0001363364 Baker Brothers Life Sciences LP 860 WASHINGTON STREET 3RD FLOOR NEW YORK NY 10014 1 0 1 0 0001087940 BAKER FELIX 860 WASHINGTON STREET 3RD FLOOR NEW YORK NY 10014 1 0 1 0 0001087939 BAKER JULIAN 860 WASHINGTON STREET, 3RD FLOOR NEW YORK NY 10014 1 0 1 0 Non-Qualified Stock Option (right to buy) 1.53 2018-06-20 4 A 0 100000 0 A 2028-06-20 Common Stock 100000 100000 I See Footnotes 50,000 non-qualified stock options ("Stock Options") convertible solely into common shares of Idera Pharmaceuticals, Inc. (the "Issuer") were granted to Julian C. Baker, a principal of Baker Bros. Advisors LP (the "Adviser") and 50,000 Stock Options were granted to Dr. Kelvin M. Neu, a full-time employee of the Adviser. The Stock Options were granted pursuant to the Issuer's 2013 Stock Incentive Plan, as amended, have a strike price of $1.53 and vest in full on the first anniversary of the date of grant, subject to continued service as a director. Julian C. Baker and Dr. Kelvin M. Neu serve on the Issuer's Board of Directors (the "Board") as representatives of 667, L.P. ("667"), Baker Brothers Life Sciences, L.P. ("Life Sciences") and 14159, L.P. ("14159", and together with 667, and Life Sciences, the "Funds"). Pursuant to the policies of the Adviser, Julian C. Baker and Dr. Kelvin M. Neu do not have any right to any of the Issuer's securities issued as part of their service on the Board and the Funds are entitled to receive all the pecuniary interest in the securities issued. The Funds each own an indirect proportionate pecuniary interest in the Stock Options. Solely as a result of Felix J. Baker's and Julian C. Baker's ownership interest in the general partners of the general partners of the Funds, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in the stock options (i.e. no direct pecuniary interest). The Adviser serves as the Investment Adviser to the Funds. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held by the Funds. Baker Bros. Advisors (GP) LLC (the "Adviser GP") is the Adviser's sole general partner. Julian C. Baker and Felix J. Baker are principals of the Adviser GP. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held by the Funds. The general partners of the Funds relinquished to the Adviser all discretion and authority with respect to the investment and voting power of the securities held by the Funds. Julian C. Baker, Felix J. Baker, the Adviser GP and the Adviser disclaim beneficial ownership of the securities held directly by the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker, the Adviser GP or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose. Remarks: Julian C. Baker and Dr. Kelvin M. Neu, respectively, a principal and a full-time employee of Baker Bros. Advisors LP (the "Adviser") are directors of Idera Pharmaceuticals, Inc. ("the Issuer"). By virtue of their representation on the Board of Directors of the Issuer, for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, the reporting persons are deemed directors by deputization of the Issuer. By: Baker Bros. Advisors LP, Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing 2018-06-21 Baker Bros. Advisors LP, Mgmt. Co. and Inv. Adviser to 14159, L.P., pursuant to authority granted by 14159 Capital, L.P., GP to 14159, L.P. Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing 2018-06-21 Baker Bros. Advisors LP, Mgmt. Co. and Inv. Adviser to 667, L.P., pursuant to authority granted by Baker Biotech Capital, L.P., GP to 667, L.P. Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing 2018-06-21 By: Baker Bros. Advisors (GP) LLC, Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing 2018-06-21 Baker Bros. Advisors LP, Mgmt. Co. and Inv. Adviser to BAKER BROTHERS LIFE SCIENCES, L.P., pursuant to authority granted by Baker Brothers Life Sciences Capital, L.P., GP to Baker Brothers Life Sciences, L.P., Name: Scott L. Lessing, Title: President /s/ 2018-06-21 /s/ Felix J. Baker 2018-06-21 /s/ Julian C. Baker 2018-06-21