SC 13G

 

 

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

 

 

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No.     )*

 

 

Rubius Therapeutics, Inc.

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

78116T 10 3

(CUSIP Number)

December 31, 2018

(Date of Event Which Requires Filing of this Statement)

 

 

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☐ Rule 13d-1(c)

☒ Rule 13d-1(d)

 

*

The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

  Flagship VentureLabs IV LLC

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  Delaware

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  5,000,000

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  5,000,000

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  5,000,000

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  6.32%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  OO


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

  Flagship Ventures Fund IV, L.P.

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  Delaware

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  20,323,593

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  20,323,593

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  20,323,593

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  25.71%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  PN


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

  Flagship Ventures Fund IV-Rx, L.P.

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  Delaware

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  3,830,402

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  3,830,402

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  3,830,402

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  4.85%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  PN


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

  Flagship Ventures Fund IV General Partner LLC

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  Delaware

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  24,153,995

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  24,153,995

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  24,153,995

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  30.56%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  OO


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

  Flagship V VentureLabs Rx Fund, L.P.

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  Delaware

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  5,789,414

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  5,789,414

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  5,789,414

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  7.32%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  PN


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

   Flagship Ventures Fund V, L.P.

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  Delaware

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  5,789,414

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  5,789,414

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  5,789,414

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  7.32%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  PN


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

   Flagship Ventures Fund V General Partner LLC

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  United States of America

  Delaware

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  11,578,828

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  11,578,828

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  11,578,828

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  14.65%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  OO


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

Flagship Ventures Opportunities Fund I, L.P.

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  Delaware

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  2,563,703

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  2,563,703

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  2,563,703

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  3.24%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  PN


 

  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

  Flagship Ventures Opportunities Fund I General Partner LLC

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  Delaware

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  2,563,703

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  2,563,703

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  2,563,703

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  3.24%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  OO


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

  Noubar B. Afeyan, Ph.D.

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  United States of America

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  38,296,526

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  38,296,526

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  38,296,526

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  48.45%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  IN


  1       

  NAMES OF REPORTING PERSONS

  I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

 

  Edwin M. Kania, Jr.

  2      

  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

  (a)  ☐        (b)  ☒

 

  3      

  SEC USE ONLY

 

  4      

  CITIZENSHIP OR PLACE OF ORGANIZATION

 

  United States of America

NUMBER OF

SHARES

  BENEFICIALLY  

OWNED BY

EACH

REPORTING

PERSON

WITH:

    5     

  SOLE VOTING POWER

 

  0

  6     

  SHARED VOTING POWER

 

  24,153,995

  7     

  SOLE DISPOSITIVE POWER

 

  0

  8     

  SHARED DISPOSITIVE POWER

 

  24,153,995

  9      

  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

  24,153,995

10      

  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

  ☐

11      

  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

  30.56%

12      

  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

  IN


Item 1(a). Name of Issuer:

Rubius Therapeutics, Inc. (the “Issuer”)

Item 1(b). Address of Issuer’s Principal Executive Offices:

325 Vassar Street, Suite 1A, Cambridge, Massachusetts 02139

Item 2(a). Names of Persons Filing:

The names of the persons filing this report (collectively, the “Reporting Persons”) are:

Flagship VentureLabs IV LLC (“VentureLabs IV”)

Flagship Ventures Fund IV, L.P. (“Flagship IV Fund”)

Flagship Ventures Fund IV-Rx, LP (“Flagship IV-Rx Fund”)

Flagship Ventures Fund IV General Partner LLC (“Flagship IV GP”)

Flagship V VentureLabs Rx Fund, L.P. (“VentureLabs Rx V”)

Flagship Ventures Fund V, L.P. (“Flagship V Fund”)

Flagship Ventures Fund V General Partner LLC (“Flagship V GP”)

Flagship Ventures Opportunities Fund I, L.P. (“Flagship Opportunities I”)

Flagship Ventures Opportunities Fund I General Partner LLC (“Flagship Opportunities GP”)

Noubar B. Afeyan, Ph.D. (“Dr. Afeyan”)

Edwin M. Kania, Jr. (“Mr. Kania)

Item 2(b). Address of Principal Business Office or, if None, Residence:

The address of the principal business office of each of the Reporting Persons is:

c/o Flagship Pioneering Inc.

55 Cambridge Parkway, Suite 800E

Cambridge, Massachusetts 02142

Item 2(c). Citizenship:

 

  VentureLabs IV

           Delaware

  Flagship IV Fund

           Delaware

  Flagship IV-Rx Fund

           Delaware

  Flagship IV GP

           Delaware

  VentureLabs Rx V

           Delaware

  Flagship V Fund

           Delaware

  Flagship V GP

           Delaware

  Flagship Opportunities I

           Delaware

  Flagship Opportunities GP

           Delaware

  Dr. Afeyan

           United States of America

  Mr. Kania

           United States of America


Item 2(d). Title of Class of Securities:

Common Stock, $0.001 par value per share (“Common Stock”).

Item 2(e). CUSIP Number:

78116T 10 3

Item 3. If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:

Not applicable.

Item 4. Ownership.

The information required by this item with respect to each Reporting Person is set forth in Rows 5 through 9 and 11 of the cover page to this Schedule 13G. The ownership percentages reported are based on 79,044,166 shares of outstanding Common Stock as of October 31, 2018, as reported in the Issuer’s 10-Q filed on November 13, 2018.

Flagship IV Fund is the manager of VentureLabs IV and, as such, may be deemed to beneficially own the shares held by VentureLabs IV.

Flagship IV GP is the general partner of each of Flagship IV Fund and Flagship IV-Rx Fund, and, as such, may be deemed to beneficially own the shares beneficially owned by Flagship IV Fund and Flagship IV-Rx Fund.

Flagship V GP is the general partner of each of Flagship V Fund and VentureLabs Rx V, and, as such, may be deemed to beneficially own the shares beneficially owned by Flagship V Fund and VentureLabs Rx V.

Flagship Opportunities GP is the general partner of Flagship Opportunities I, and, as such, may be deemed to beneficially own the shares held by Flagship Opportunities I.

Dr. Afeyan and Mr. Kania are the managers of Flagship Fund IV GP, and as such, may be deemed to beneficially own the shares beneficially owned by Flagship IV Fund and Flagship IV-Rx Fund. While Mr. Kania is retired from Flagship Pioneering he continues to serve as a manager of Flagship Fund IV GP.

Dr. Afeyan is the managing member of Flagship Fund V GP and Flagship Opportunities GP, and as such, may be deemed to beneficially own the shares beneficially owned by Flagship V Fund, VentureLabs Rx V Fund and Flagship Opportunities I.

Each of the Reporting Persons expressly disclaims beneficial ownership of the shares reported in this Schedule 13G except to the extent of its or his pecuniary interest in such shares.


Item 5. Ownership of Five Percent or Less of a Class.

If this statement is being filed to report the fact that as of the date hereof the Reporting Persons have ceased to be the beneficial owner of more than five percent of the class of securities, check the following ☐.

Item 6. Ownership of More than Five Percent on Behalf of Another Person.

Not applicable.

 

Item 7. 

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.

Not applicable.

Item 8. Identification and Classification of Members of the Group.

Not applicable.

Item 9. Notice of Dissolution of Group.

Not applicable.

Item 10. Certification.

Not applicable.

Material Filed as Exhibits.

Exhibit 1 – Agreement regarding filing of joint Schedule 13G.


SIGNATURE

After reasonable inquiry and to the best of its knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

 

Date: February 12, 2019
FLAGSHIP VENTURELABS IV LLC
By:   Flagship Ventures Fund IV, L.P.
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND IV, L.P.
By:   Flagship Ventures Fund IV General Partner LLC
  General Partner
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND IV-RX, L.P.
By:   Flagship Ventures Fund IV General Partner LLC
  General Partner
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND IV GENERAL PARTNER LLC
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP V VENTURLABS RX FUND, L.P.
By:   Flagship Ventures Fund V General Partner LLC
  General Partner


By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND V, L.P.
By:   Flagship Ventures Fund V General Partner LLC
  General Partner
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND V GENERAL PARTNER LLC
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES OPPORTUNITIES FUND I, L.P.
By:   Flagship Ventures Opportunities Fund I General Partner LLC
  General Partner
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
           Manager
FLAGSHIP VENTURES OPPORTUNITIES FUND I GENERAL PARTNER LLC
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager

/s/ Noubar B. Afeyan, Ph.D.

NOUBAR B. AFEYAN, PH,D.

/s/ Edwin M. Kania, Jr.

EDWIN M. KANIA, JR.


EXHIBIT 1

AGREEMENT

The persons below hereby agree that the Schedule 13G to which this agreement is attached as an exhibit, as well as all future amendments to such Schedule 13G, shall be filed on behalf of each of them. This agreement is intended to satisfy the requirements of Rule 13d-1(k)(1)(iii) under the Securities Exchange Act of 1934.

 

Date:   February 12, 2019
FLAGSHIP VENTURELABS IV LLC
By:   Flagship Ventures Fund IV, L.P.
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND IV, L.P.
By:   Flagship Ventures Fund IV General Partner LLC
  General Partner
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND IV-RX, L.P.
By:   Flagship Ventures Fund IV General Partner LLC
  General Partner
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND IV GENERAL PARTNER LLC
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP V VENTURLABS RX FUND, L.P.


By:   Flagship Ventures Fund V General Partner LLC
  General Partner
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND V, L.P.
By:   Flagship Ventures Fund V General Partner LLC
  General Partner
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES FUND V GENERAL PARTNER LLC
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager
FLAGSHIP VENTURES OPPORTUNITIES FUND I, L.P.
By:   Flagship Ventures Opportunities Fund I General Partner LLC
  General Partner
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
           Manager
FLAGSHIP VENTURES OPPORTUNITIES FUND I GENERAL PARTNER LLC
By:  

/s/ Noubar B. Afeyan, Ph.D.

  Noubar B. Afeyan, Ph.D.
  Manager

/s/ Noubar B. Afeyan, Ph.D.

NOUBAR B. AFEYAN, PH,D.

/s/ Edwin M. Kania, Jr.

EDWIN M. KANIA, JR.