KRRO

SEC source: 0001127602-20-014596 · form4.xml · nonDerivative · entry 1

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 454,753

F1 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 20, 2019.

F2 · price: This transaction was executed in multiple trades through a broker-dealer at prices ranging from $16.07 to $16.74. The price reported in this column reflects the weighted average sales price. Upon request, the reporting person will provide to the SEC staff full information regarding the number of Shares sold at each price.

SEC source: 0001127602-20-014490 · form4.xml · nonDerivative · entry 1

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 455,482

F1 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 20, 2019.

F2 · price: This transaction was executed in multiple trades through a broker-dealer at prices ranging from $16.00 to $16.44. The price reported in this column reflects the weighted average sales price. Upon request, the reporting person will provide to the SEC staff full information regarding the number of Shares sold at each price.

SEC source: 0001127602-20-014478 · form4.xml · nonDerivative · entry 1

Loose Christopher R. · CIK 0001785299 · Chief Scientific Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 196,282

F1 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 10, 2019.

F2 · price: This transaction was executed in multiple trades through a broker-dealer at prices ranging from $14.51 to $15.1. The price reported in this column reflects the weighted average sales price. Upon request, the reporting person will provide to the SEC staff full information regarding the number of Shares sold at each price.

SEC source: 0001127602-20-014220 · form4.xml · nonDerivative · entry 1

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 456,892

F1 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 20, 2019.

F2 · price: This transaction was executed in multiple trades through a broker-dealer at prices ranging from $16.00 to $16.02. The price reported in this column reflects the weighted average sales price. Upon request, the reporting person will provide to the SEC staff full information regarding the number of Shares sold at each price.

SEC source: 0001127602-20-014027 · form4.xml · nonDerivative · entry 1

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 459,992

F1 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 20, 2019.

F2 · price: This transaction was executed in multiple trades through a broker-dealer at prices ranging from $14.73 to $15.465. The price reported in this column reflects the weighted average sales price. Upon request, the reporting person will provide to the SEC staff full information regarding the number of Shares sold at each price.

SEC source: 0001127602-20-013565 · form4.xml · nonDerivative · entry 1

Loose Christopher R. · CIK 0001785299 · Chief Scientific Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 200,782

F1 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 10, 2019.

F2 · price: This transaction was executed in multiple trades through a broker-dealer at prices ranging from $14.71 to $15.68. The price reported in this column reflects the weighted average sales price. Upon request, the reporting person will provide to the SEC staff full information regarding the number of Shares sold at each price.

SEC source: 0001127602-20-005628 · form4.xml · derivative · entry 1

LeBel Carl · CIK 0001439275 · Chief Development Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 57,500

Underlying: Common Stock · 57,500 shares

Expires 2030-02-11

F1 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a four year period commencing on February 1, 2020, and will be fully vested and exercisable on January 1, 2024.

SEC source: 0001127602-20-005638 · form4.xml · derivative · entry 1

Hilt Dana Charles · CIK 0001360756 · Chief Medical Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 50,000

Underlying: Common Stock · 50,000 shares

Expires 2030-02-11

F1 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a four year period commencing on February 1, 2020, and will be fully vested and exercisable on January 1, 2024.

SEC source: 0001127602-20-005645 · form4.xml · derivative · entry 1

Mitrano Richard J. · CIK 0001785287 · VP Finance & Operations

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 18,000

Underlying: Common Stock · 18,000 shares

Expires 2030-02-11

F1 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a four year period commencing on February 1, 2020, and will be fully vested and exercisable on January 1, 2024.

SEC source: 0001127602-20-005650 · form4.xml · derivative · entry 1

Arnold Wendy S · CIK 0001802649 · Chief People Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 130,000

Underlying: Common Stock · 130,000 shares

Expires 2030-02-11

F1 · derivative.exercise_date: The option vests and becomes exercisable as to 25% on February 3, 2021 and in equal monthly installments on the same day of each month thereafter and will be fully vested and exercisable on February 3, 2024.

SEC source: 0001127602-20-005641 · form4.xml · derivative · entry 1

Loose Christopher R. · CIK 0001785299 · Chief Scientific Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 57,500

Underlying: Common Stock · 57,500 shares

Expires 2030-02-11

F1 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a four year period commencing on February 1, 2020, and will be fully vested and exercisable on January 1, 2024.

SEC source: 0001127602-20-005635 · form4.xml · derivative · entry 1

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 242,500

Underlying: Common Stock · 242,500 shares

Expires 2030-02-11

F1 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a four year period commencing on February 1, 2020, and will be fully vested and exercisable on January 1, 2024

SEC source: 0000899243-20-002536 · doc4.xml · derivative · entry 11

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 20,778 shares

Expires 2029-04-16

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · derivative.exercise_date: The option is fully vested.

SEC source: 0000899243-20-002536 · doc4.xml · derivative · entry 10

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 20,778 shares

Expires 2029-04-16

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · derivative.exercise_date: The option is fully vested.

SEC source: 0000899243-20-002536 · doc4.xml · derivative · entry 9

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 32,918

Underlying: Common Stock · 21,827 shares

Expires 2029-04-16

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F3 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a two year period commencing on February 1, 2019, and will be fully vested and exercisable on January 1, 2021.

SEC source: 0000899243-20-002536 · doc4.xml · derivative · entry 8

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 50,072

Underlying: Common Stock · 16,691 shares

Expires 2028-05-21

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a four year period commencing on February 1, 2018, and will be fully vested and exercisable on January 1, 2022.

SEC source: 0000899243-20-002536 · doc4.xml · derivative · entry 7

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 12,063

Underlying: Common Stock · 8,042 shares

Expires 2027-06-28

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a four year period commencing on February 1, 2017, and will be fully vested and exercisable on January 1, 2021.

SEC source: 0000899243-20-002536 · doc4.xml · nonDerivative · entry 5

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · The Marc Andrew Cohen Revocable Trust

Disclosed balance after: 605,820

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-20-002536 · doc4.xml · nonDerivative · entry 4

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · The Marc Andrew Cohen Revocable Trust

Disclosed balance after: 585,042

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-20-002536 · doc4.xml · nonDerivative · entry 3

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · The Marc Andrew Cohen Revocable Trust

Disclosed balance after: 564,264

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-20-002536 · doc4.xml · nonDerivative · entry 2

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · The Marc Andrew Cohen Revocable Trust

Disclosed balance after: 542,437

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-20-002536 · doc4.xml · nonDerivative · entry 1

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · The Marc Andrew Cohen Revocable Trust

Disclosed balance after: 525,746

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-20-000051 · doc4.xml · derivative · entry 4

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 310,647

Underlying: Common Stock · 20,787 shares

Expires 2028-05-21

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a four year period commencing on February 1, 2018, and will be fully vested and exercisable on January 1, 2022.

SEC source: 0000899243-20-000051 · doc4.xml · derivative · entry 3

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 50,866

Underlying: Common Stock · 36,590 shares

Expires 2027-06-28

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_date: The option vests and becomes exercisable in equal monthly installments over a four year period commencing on February 1, 2017, and will be fully vested and exercisable on January 1, 2021.

SEC source: 0000899243-20-000051 · doc4.xml · nonDerivative · entry 2

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 465,228

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-20-000051 · doc4.xml · nonDerivative · entry 1

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 444,441

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0000899243-19-028544 · doc4.xml · derivative · entry 1

COHEN MARC A · CIK 0001132945 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 20,778

Underlying: Common Stock · 20,778 shares

Expires 2029-04-16

F1 · derivative.exercise_date: The option is fully vested.

SEC source: 0000899243-19-028542 · doc4.xml · derivative · entry 1

LeBel Carl · CIK 0001439275 · Chief Development Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 23,555

Underlying: Common Stock · 23,555 shares

Expires 2029-04-16

F1 · derivative.exercise_date: The option is fully vested.

SEC source: 0000899243-19-028546 · doc4.xml · derivative · entry 1

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 96,361

Underlying: Common Stock · 96,361 shares

Expires 2029-04-16

F1 · derivative.exercise_date: The option is fully vested.

SEC source: 0000899243-19-028543 · doc4.xml · derivative · entry 1

Loose Christopher R. · CIK 0001785299 · Chief Scientific Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 64,241

Underlying: Common Stock · 64,241 shares

Expires 2029-04-16

F1 · derivative.exercise_date: The option is fully vested.

SEC source: 0001193805-19-000911 · e619107_4-ft.xml · derivative · entry 5

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Special Situations Fund, L.P. · CIK 0001354395 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt IV, L.P. · CIK 0001713467 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund IV, L.P. · CIK 0001680307 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Special Situations Fund, L.P.

Disclosed balance after: 0

Underlying: Common Stock · 472,860 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F1 · price: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F1 · derivative.exercise_date: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F1 · derivative.expiration_date: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt IV, L.P. is the general partner of Deerfield Private Design Fund IV, L.P. ("Fund IV"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. and Deerfield Special Situations Fund, L.P. (collectively with Fund IV, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt IV, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Funds is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0001193805-19-000911 · e619107_4-ft.xml · derivative · entry 4

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Special Situations Fund, L.P. · CIK 0001354395 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt IV, L.P. · CIK 0001713467 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund IV, L.P. · CIK 0001680307 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Private Design Fund IV, L.P.

Disclosed balance after: 0

Underlying: Common Stock · 472,860 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F1 · price: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F1 · derivative.exercise_date: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F1 · derivative.expiration_date: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt IV, L.P. is the general partner of Deerfield Private Design Fund IV, L.P. ("Fund IV"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. and Deerfield Special Situations Fund, L.P. (collectively with Fund IV, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt IV, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Funds is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0001193805-19-000911 · e619107_4-ft.xml · nonDerivative · entry 3

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Special Situations Fund, L.P. · CIK 0001354395 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt IV, L.P. · CIK 0001713467 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund IV, L.P. · CIK 0001680307 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Partners, L.P.

Disclosed balance after: 285,714

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt IV, L.P. is the general partner of Deerfield Private Design Fund IV, L.P. ("Fund IV"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. and Deerfield Special Situations Fund, L.P. (collectively with Fund IV, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt IV, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Funds is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0001193805-19-000911 · e619107_4-ft.xml · nonDerivative · entry 2

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Special Situations Fund, L.P. · CIK 0001354395 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt IV, L.P. · CIK 0001713467 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund IV, L.P. · CIK 0001680307 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Private Design Fund IV, L.P.

Disclosed balance after: 472,860

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt IV, L.P. is the general partner of Deerfield Private Design Fund IV, L.P. ("Fund IV"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. and Deerfield Special Situations Fund, L.P. (collectively with Fund IV, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt IV, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Funds is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0001193805-19-000911 · e619107_4-ft.xml · nonDerivative · entry 1

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Special Situations Fund, L.P. · CIK 0001354395 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt IV, L.P. · CIK 0001713467 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund IV, L.P. · CIK 0001680307 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Special Situations Fund, L.P.

Disclosed balance after: 472,860

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of Series C Preferred Stock automatically converted into 0.148467077 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis, after giving effect to the 1-for-6.7355 reverse stock split of the Issuer's common stock effected by the Issuer on September 20, 2019).

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt IV, L.P. is the general partner of Deerfield Private Design Fund IV, L.P. ("Fund IV"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. and Deerfield Special Situations Fund, L.P. (collectively with Fund IV, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt IV, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Funds is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0000899243-19-025216 · doc4.xml · derivative · entry 5

BARBERICH TIMOTHY J · CIK 0001120355 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 9,457 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

SEC source: 0000899243-19-025216 · doc4.xml · derivative · entry 4

BARBERICH TIMOTHY J · CIK 0001120355 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · The Barberich Family Trust

Disclosed balance after: 0

Underlying: Common Stock · 80,650 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

SEC source: 0000899243-19-025216 · doc4.xml · derivative · entry 3

BARBERICH TIMOTHY J · CIK 0001120355 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 75,165 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

SEC source: 0000899243-19-025216 · doc4.xml · nonDerivative · entry 2

BARBERICH TIMOTHY J · CIK 0001120355 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · The Barberich Family Trust

Disclosed balance after: 80,650

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · shares: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

SEC source: 0000899243-19-025216 · doc4.xml · nonDerivative · entry 1

BARBERICH TIMOTHY J · CIK 0001120355 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 102,089

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · shares: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077 for one basis.

SEC source: 0000899243-19-025213 · doc4.xml · derivative · entry 6

MARCUS JOEL S · CIK 0001216955 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · Alexandria Venture Investments, LLC

Disclosed balance after: 0

Underlying: Common Stock · 338,259 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

SEC source: 0000899243-19-025213 · doc4.xml · derivative · entry 5

MARCUS JOEL S · CIK 0001216955 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · Alexandria Venture Investments, LLC

Disclosed balance after: 0

Underlying: Common Stock · 617,916 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

SEC source: 0000899243-19-025213 · doc4.xml · derivative · entry 4

MARCUS JOEL S · CIK 0001216955 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 124,685 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

SEC source: 0000899243-19-025213 · doc4.xml · derivative · entry 3

MARCUS JOEL S · CIK 0001216955 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 227,824 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

SEC source: 0000899243-19-025213 · doc4.xml · nonDerivative · entry 2

MARCUS JOEL S · CIK 0001216955 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · Alexandria Venture Investments, LLC

Disclosed balance after: 956,175

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · shares: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

SEC source: 0000899243-19-025213 · doc4.xml · nonDerivative · entry 1

MARCUS JOEL S · CIK 0001216955 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 352,509

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · shares: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

SEC source: 0000899243-19-025217 · doc4.xml · derivative · entry 3

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 4,033 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

SEC source: 0000899243-19-025217 · doc4.xml · derivative · entry 2

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 6,530 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

SEC source: 0000899243-19-025217 · doc4.xml · nonDerivative · entry 1

Lucchino David L. · CIK 0001785288 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 407,851

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · shares: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

SEC source: 0000899243-19-025214 · doc4.xml · derivative · entry 2

Loose Christopher R. · CIK 0001785299 · Chief Scientific Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 6,708 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · price: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.exercise_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.

F1 · derivative.expiration_date: Upon the closing of the Issuer's initial public offering, each share of preferred stock automatically converted into shares of the Issuer's common stock on a 0.148467077-for-one basis.