REPL

SEC source: 0001104659-21-005570 · tm213368-5_4seq1.xml · nonDerivative · entry 5

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 181,721

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: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · derivative · entry 10

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 73,203

Underlying: Common Stock · 5,727 shares

Expires 2025-11-01

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.

F5 · derivative.exercise_date: The reporting person was granted an option to purchase 149,203 shares of the Issuer's common stock on November 1, 2015. All of the shares underlying such stock option have vested and are exercisable as of the date hereof.

SEC source: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · nonDerivative · entry 7

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 175,994

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on December 14, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $42.00 to $42.76. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

F4 · balance_after: Following the sales reported on this Form 4, the reporting person continues to beneficially own 175,994 shares of the Issuer's common stock. The reporting person also holds options to acquire an aggregate of 458,852 shares of the Issuer's common stock, 284,936 of which are exercisable as of the date hereof. The original Form 4 filed on January 19, 2021 is being amended by this Form 4 solely to correct an administrative error, which misreported the total number of options held by the reporting person and the amount exercisable as of January 19, 2021.

SEC source: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · nonDerivative · entry 6

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 181,121

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on December 14, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F2 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $42.88 to $43.86. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · nonDerivative · entry 5

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 181,721

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: 0001104659-21-005571 · tm213368-6_4seq1.xml · nonDerivative · entry 6

Astley-Sparke Philip · CIK 0001376491 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,263,729

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 6, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F6 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $42.56 to $43.25. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001104659-21-005571 · tm213368-6_4seq1.xml · nonDerivative · entry 5

Astley-Sparke Philip · CIK 0001376491 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,273,138

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 6, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F5 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $43.26 to $44.25. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001104659-21-005571 · tm213368-6_4seq1.xml · nonDerivative · entry 4

Astley-Sparke Philip · CIK 0001376491 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,279,197

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 6, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F4 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.55 to $45.26. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0000899243-21-002339 · doc4.xml · nonDerivative · entry 2

Omega Fund IV, L.P. · CIK 0001528382 · Director · 10% owner

Omega Fund IV GP, L.P. · CIK 0001528383 · 10% owner

Omega Fund IV G.P. Manager, Ltd. · CIK 0001624456 · 10% owner

Stampacchia Otello · CIK 0001361712 · Director

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,325,391

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F1 · price: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F3 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.90 to $45.65 inclusive. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

F4 · ownership.direct: The reported securities are held directly by Omega Fund IV, L.P. ("Omega IV"). The reported securities may be deemed to be beneficially owned by each of Omega Fund IV GP, L.P. ("Omega IV GP"), as the general partner of Omega IV, and Omega Fund IV GP Manager, Ltd. ("Omega IV GP Manager"), as the general partner of Omega IV GP. Otello Stampacchia and Anne-Mari Paster are all the shareholders and directors of Omega IV GP Manager and have shared voting and investment power over the shares held by Omega IV. Each of Omega IV GP, Omega Fund IV GP Manager and the Omega Directors disclaims beneficial ownership of the securities reported herein, except to the extent of its or their pecuniary interest therein, if any. Otello Stampacchia is a director of the issuer.

SEC source: 0001104659-21-005568 · tm213368-4_4seq1.xml · nonDerivative · entry 3

Love Colin · CIK 0001376493 · Chief Operating Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 954,381

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on June 12, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F4 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $42.62 to $43.39. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001104659-21-005568 · tm213368-4_4seq1.xml · nonDerivative · entry 2

Love Colin · CIK 0001376493 · Chief Operating Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 966,777

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on June 12, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $43.42 to $44.41. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001104659-21-005568 · tm213368-4_4seq1.xml · nonDerivative · entry 1

Love Colin · CIK 0001376493 · Chief Operating Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 974,324

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on June 12, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F2 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.75 to $45.50. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001104659-21-005570 · tm213368-5_4seq1.xml · derivative · entry 9

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 78,930

Underlying: Common Stock · 29,273 shares

Expires 2025-11-01

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.

F5 · derivative.exercise_date: The reporting person was granted an option to purchase 149,203 shares of the Issuer's common stock on November 1, 2015. All of the shares underlying such stock option have vested and are exercisable as of the date hereof.

SEC source: 0001104659-21-005570 · tm213368-5_4seq1.xml · nonDerivative · entry 4

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 175,994

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on December 14, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

SEC source: 0001104659-21-005570 · tm213368-5_4seq1.xml · nonDerivative · entry 3

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 205,267

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: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · derivative · entry 9

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 78,930

Underlying: Common Stock · 29,273 shares

Expires 2025-11-01

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.

F5 · derivative.exercise_date: The reporting person was granted an option to purchase 149,203 shares of the Issuer's common stock on November 1, 2015. All of the shares underlying such stock option have vested and are exercisable as of the date hereof.

SEC source: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · nonDerivative · entry 4

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 175,994

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on December 14, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

SEC source: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · nonDerivative · entry 3

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 205,267

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: 0001104659-21-004879 · tm213368-1_4seq1.xml · derivative · entry 7

Franchi Jean M. · CIK 0001653053 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 140,000

Underlying: Common Stock · 14,900 shares

Expires 2029-12-09

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: 25% of the shares underlying this stock option vested on December 9, 2020, the remainder of the shares underlying this stock option will continue to vest in approximately equal monthly installments thereafter until December 9, 2023.

SEC source: 0001104659-21-004879 · tm213368-1_4seq1.xml · nonDerivative · entry 5

Franchi Jean M. · CIK 0001653053 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 13, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F3 · balance_after: The reporting person continues to hold options to acquire 196,350 shares of the Issuer's common stock, 8,750 of which are exercisable as of the date hereof.

SEC source: 0001104659-21-004879 · tm213368-1_4seq1.xml · nonDerivative · entry 4

Franchi Jean M. · CIK 0001653053 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 600

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 13, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F2 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.01 to $45.00. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001104659-21-004879 · tm213368-1_4seq1.xml · nonDerivative · entry 3

Franchi Jean M. · CIK 0001653053 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 14,900

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: 0001104659-21-005571 · tm213368-6_4seq1.xml · nonDerivative · entry 3

Astley-Sparke Philip · CIK 0001376491 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,280,297

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 6, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

SEC source: 0001104659-21-005571 · tm213368-6_4seq1.xml · nonDerivative · entry 2

Astley-Sparke Philip · CIK 0001376491 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,280,397

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 6, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $43.14 to $44.07. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001104659-21-005571 · tm213368-6_4seq1.xml · nonDerivative · entry 1

Astley-Sparke Philip · CIK 0001376491 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,287,845

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 6, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F2 · price: The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.09 to $45.08. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0000899243-21-002339 · doc4.xml · nonDerivative · entry 1

Omega Fund IV, L.P. · CIK 0001528382 · Director · 10% owner

Omega Fund IV GP, L.P. · CIK 0001528383 · 10% owner

Omega Fund IV G.P. Manager, Ltd. · CIK 0001624456 · 10% owner

Stampacchia Otello · CIK 0001361712 · Director

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,327,307

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F1 · price: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.90 to $45.68 inclusive. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

F4 · ownership.direct: The reported securities are held directly by Omega Fund IV, L.P. ("Omega IV"). The reported securities may be deemed to be beneficially owned by each of Omega Fund IV GP, L.P. ("Omega IV GP"), as the general partner of Omega IV, and Omega Fund IV GP Manager, Ltd. ("Omega IV GP Manager"), as the general partner of Omega IV GP. Otello Stampacchia and Anne-Mari Paster are all the shareholders and directors of Omega IV GP Manager and have shared voting and investment power over the shares held by Omega IV. Each of Omega IV GP, Omega Fund IV GP Manager and the Omega Directors disclaims beneficial ownership of the securities reported herein, except to the extent of its or their pecuniary interest therein, if any. Otello Stampacchia is a director of the issuer.

SEC source: 0001104659-21-005570 · tm213368-5_4seq1.xml · derivative · entry 8

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 108,203

Underlying: Common Stock · 20,000 shares

Expires 2025-11-01

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.

F5 · derivative.exercise_date: The reporting person was granted an option to purchase 149,203 shares of the Issuer's common stock on November 1, 2015. All of the shares underlying such stock option have vested and are exercisable as of the date hereof.

SEC source: 0001104659-21-005570 · tm213368-5_4seq1.xml · nonDerivative · entry 2

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 175,994

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on December 14, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

SEC source: 0001104659-21-005570 · tm213368-5_4seq1.xml · nonDerivative · entry 1

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 195,994

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: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · derivative · entry 8

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 108,203

Underlying: Common Stock · 20,000 shares

Expires 2025-11-01

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.

F5 · derivative.exercise_date: The reporting person was granted an option to purchase 149,203 shares of the Issuer's common stock on November 1, 2015. All of the shares underlying such stock option have vested and are exercisable as of the date hereof.

SEC source: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · nonDerivative · entry 2

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 175,994

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on December 14, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

SEC source: 0001104659-21-093670 · tm2122438-3_4aseq1.xml · nonDerivative · entry 1

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 195,994

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: 0001104659-21-004879 · tm213368-1_4seq1.xml · derivative · entry 6

Franchi Jean M. · CIK 0001653053 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 154,900

Underlying: Common Stock · 100 shares

Expires 2029-12-09

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: 25% of the shares underlying this stock option vested on December 9, 2020, the remainder of the shares underlying this stock option will continue to vest in approximately equal monthly installments thereafter until December 9, 2023.

SEC source: 0001104659-21-004879 · tm213368-1_4seq1.xml · nonDerivative · entry 2

Franchi Jean M. · CIK 0001653053 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 13, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

SEC source: 0001104659-21-004879 · tm213368-1_4seq1.xml · nonDerivative · entry 1

Franchi Jean M. · CIK 0001653053 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 100

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: 0001104659-20-139951 · tm2039457-1_4seq1.xml · derivative · entry 2

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 32,758

Underlying: Common Stock · 50,704 shares

Expires 2026-03-01

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: 25% of the shares underlying this stock option vested on February 28, 2017 and the remainder of the shares underlying this stock option vested in 36 approximately equal monthly installments thereafter.

SEC source: 0001104659-20-139951 · tm2039457-1_4seq1.xml · nonDerivative · entry 1

Esposito Pamela · CIK 0001744425 · Chief Business Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 175,994

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: 0001104659-20-139953 · tm2039457-2_4seq1.xml · nonDerivative · entry 1

Coffin Robert · CIK 0001376492 · Director · President & Chief R&D Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,804,118

F1 · kind: The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on November 16, 2020 that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

F2 · balance_after: Following the sales reported on this Form 4, the reporting person continues to beneficially own 1,804,118 shares of the Issuer's common stock. The reporting person also holds options to acquire 977,599 shares of the Issuer's common stock, 468,928 of which are exercisable as of the date hereof.

SEC source: 0001209191-20-064846 · doc4.xml · nonDerivative · entry 3

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 19,285

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F4 · ownership.nature: The shares are held directly by AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims beneficial ownership of such securities held by AVA X LP, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064846 · doc4.xml · nonDerivative · entry 2

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 951,558

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F3 · ownership.nature: The shares are held directly by Atlas Venture Opportunity Fund I, L.P. ("Atlas Venture Opportunity Fund I"). The general partner of Atlas Venture Opportunity Fund I is Atlas Venture Associates Opportunity I, L.P. ("AVAO I LP"). Atlas Venture Associates Opportunity I, LLC ("AVAO I LLC") is the general partner of AVAO I LP. The Reporting Person is a member of AVAO I LLC and disclaims beneficial ownership of such securities held by Atlas Venture Opportunity Fund I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064846 · doc4.xml · nonDerivative · entry 1

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 2,263,627

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F2 · ownership.nature: The shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims beneficial ownership of such securities held by Atlas Venture Fund X, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064186 · doc4.xml · nonDerivative · entry 15

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 19,550

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F8 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.95 to $42.37 inclusive.

F6 · ownership.nature: The shares are held directly by AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims beneficial ownership of such securities held by AVA X LP, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064186 · doc4.xml · nonDerivative · entry 14

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 952,600

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F8 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.95 to $42.37 inclusive.

F5 · ownership.nature: The shares are held directly by Atlas Venture Opportunity Fund I, L.P. ("Atlas Venture Opportunity Fund I"). The general partner of Atlas Venture Opportunity Fund I is Atlas Venture Associates Opportunity I, L.P. ("AVAO I LP"). Atlas Venture Associates Opportunity I, LLC ("AVAO I LLC") is the general partner of AVAO I LP. The Reporting Person is a member of AVAO I LLC and disclaims beneficial ownership of such securities held by Atlas Venture Opportunity Fund I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064186 · doc4.xml · nonDerivative · entry 13

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 2,266,639

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F8 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.95 to $42.37 inclusive.

F3 · ownership.nature: The shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims beneficial ownership of such securities held by Atlas Venture Fund X, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064186 · doc4.xml · nonDerivative · entry 12

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 20,247

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F7 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.95 to $42.80 inclusive.

F6 · ownership.nature: The shares are held directly by AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims beneficial ownership of such securities held by AVA X LP, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064186 · doc4.xml · nonDerivative · entry 11

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 955,385

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F7 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.95 to $42.80 inclusive.

F5 · ownership.nature: The shares are held directly by Atlas Venture Opportunity Fund I, L.P. ("Atlas Venture Opportunity Fund I"). The general partner of Atlas Venture Opportunity Fund I is Atlas Venture Associates Opportunity I, L.P. ("AVAO I LP"). Atlas Venture Associates Opportunity I, LLC ("AVAO I LLC") is the general partner of AVAO I LP. The Reporting Person is a member of AVAO I LLC and disclaims beneficial ownership of such securities held by Atlas Venture Opportunity Fund I, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064186 · doc4.xml · nonDerivative · entry 10

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 2,274,692

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F7 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.95 to $42.80 inclusive.

F3 · ownership.nature: The shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims beneficial ownership of such securities held by Atlas Venture Fund X, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064186 · doc4.xml · nonDerivative · entry 9

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 21,013

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F6 · ownership.nature: The shares are held directly by AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims beneficial ownership of such securities held by AVA X LP, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064186 · doc4.xml · nonDerivative · entry 8

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 21,019

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F4 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $43.00 to $43.44 inclusive.

F6 · ownership.nature: The shares are held directly by AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims beneficial ownership of such securities held by AVA X LP, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001209191-20-064186 · doc4.xml · nonDerivative · entry 7

Rhodes Jason P · CIK 0001577014 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnote

Disclosed balance after: 21,049

F1 · kind: Shares were sold pursuant to a Rule 10b5-1 trading plan.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.975 to $42.97 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 footnotes (2), (4), (7) and (8).

F6 · ownership.nature: The shares are held directly by AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims beneficial ownership of such securities held by AVA X LP, except to the extent of his pecuniary interest therein, if any.