X0306 4 2021-01-20 0 0001496671 Calithera Biosciences, Inc. CALA 0001579629 Ray Sumita C/O CALITHERA BIOSCIENCES, INC. 343 OYSTER POINT BLVD. #200 SOUTH SAN FRANCISCO CA 94080 0 1 0 0 See Remarks Common Stock 2021-01-20 4 A 0 30000 0.00 A 45000 D Common Stock 2021-01-20 4 A 0 12000 0.00 A 57000 D Employee Stock Option (Right to Buy) 2.98 2021-01-20 4 A 0 125000 0.00 A 2031-01-20 Common Stock 125000 125000 D The shares of Common Stock are to be acquired upon the vesting of a Restricted Stock Unit award granted to the Reporting Person. The Restricted Stock Units shall vest as follows: one-fourth (1/4th) of the shares subject to the Restricted Stock Unit will vest each year after January 20, 2021 until the Restricted Stock Units are fully vested. The Restricted Stock Unit shall be subject to accelerated vesting as set forth in the optionee's employment agreement with the Company. Includes 2,500 shares acquired under the Company's 2014 Employee Stock Purchase Plan on each of June 8, 2018, December 10, 2018, June 10, 2019, December 10, 2019, June 10, 2020 and December 10, 2020. The shares of Common Stock are to be acquired upon the vesting of a Restricted Stock Unit award granted to the Reporting Person. The Restricted Stock Units shall fully vest on January 3, 2022. The Restricted Stock Unit shall be subject to accelerated vesting as set forth in the optionee's employment agreement with the Company. One-fourth (1/4th) of the Option vests one year after January 20, 2021; the balance of the Option vests in a series of thirty-six (36) successive equal monthly installments thereafter. The Option shall be subject to accelerated vesting as set forth in the optionee's employment agreement with the Company. SVP, GENERAL COUNSEL & CHIEF COMPLIANCE OFFICER /s/ Sumita Ray 2021-01-22