X0306 4 2019-12-26 0 0001399529 Dicerna Pharmaceuticals Inc DRNA 0001266625 ROSSKAMP RALF C/O DICERNA PHARMACEUTICALS, INC. 33 HAYDEN AVENUE LEXINGTON MA 02421 0 1 0 0 Chief Medical Officer Common Stock 2019-12-26 4 M 0 20000 2.91 A 23564 D Common Stock 2019-12-26 4 S 0 20000 22.6882 D 3564 D Employee Stock Option (Right to Buy) 2.91 2019-12-26 4 M 0 20000 0.00 D 2027-06-15 Common Stock 20000 230000 D The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 25, 2019. The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $22.48 to $23.13, inclusive. The reporting person undertakes to provide to Dicerna Pharmaceuticals, Inc., any security holder of to Dicerna Pharmaceuticals, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4. Includes shares acquired under the DRNA 2014 Employee Stock Purchase Plan in transactions that were exempt under Rule 16b-3(c). The option vested 25% on the first-year anniversary of the vesting start date of June 15, 2017 and the remaining 75% vests in 36 substantially equal monthly installments thereafter, subject in each case to the reporting person's continued employment with the issuer through the applicable vesting date. /s/ John B. Green, attorney-in-fact 2019-12-27