X0306 4 2020-10-20 0 0001689548 Praxis Precision Medicines, Inc. PRAX 0001736665 BSOF Parallel Master Fund L.P. C/O THE BLACKSTONE GROUP INC. 345 PARK AVENUE NEW YORK NY 10154 0 0 1 0 0001728529 Blackstone Strategic Opportunity Associates L.L.C. C/O THE BLACKSTONE GROUP INC. 345 PARK AVENUE NEW YORK NY 10154 0 0 1 0 0001728531 Blackstone Alternative Solutions L.L.C. C/O THE BLACKSTONE GROUP INC. 345 PARK AVENUE NEW YORK NY 10154 0 0 1 0 Common Stock 2020-10-20 4 C 0 3446711 A 4147645 I See Footnotes Common Stock 2020-10-20 4 C 0 2361198 A 6508843 I See Footnotes Common Stock 2020-10-20 4 C 0 659116 A 7167959 I See Footnotes Common Stock 2020-10-20 4 C 0 261318 A 7429277 I See Footnotes Common Stock 2020-10-20 4 C 0 907378 A 907378 I See Footnotes Common Stock 2020-10-20 4 C 0 164832 A 7594109 I See Footnotes Series A Redeemable Convertible Preferred Stock 2020-10-20 4 C 0 7375799 0.00 D Common Stock 3446711 0 I See Footnotes Series B Redeemable Convertible Preferred Stock 2020-10-20 4 C 0 5052852 0.00 D Common Stock 2361198 0 I See Footnotes Series B-1 Redeemable Convertible Preferred Stock 2020-10-20 4 C 0 1410477 0.00 D Common Stock 659116 0 I See Footnotes Series C Redeemable Convertible Preferred Stock 2020-10-20 4 C 0 559208 0.00 D Common Stock 261318 0 I See Footnotes Series C Redeemable Convertible Preferred Stock 2020-10-20 4 C 0 1941748 0.00 D Common Stock 907378 0 I See Footnotes Series C-1 Redeemable Convertible Preferred Stock 2020-10-20 4 C 0 352734 0.00 D Common Stock 164832 0 I See Footnotes All series of Preferred Stock of the Issuer automatically converted into common stock of the Issuer on a 1-for-2.14 basis. Each series of Preferred Stock had no expiration date. Reflects securities held directly by Clarus Lifesciences III, L.P. Clarus Ventures III GP, L.P. is the general partner of Clarus Lifesciences III, L.P. Blackstone Clarus III L.L.C. is the general partner of Clarus Ventures III GP, L.P. The sole member of Blackstone Clarus III L.L.C. is Blackstone Holdings II L.P. Reflects securities held directly by BSOF Parallel Master Fund L.P. Blackstone Strategic Opportunity Associates L.L.C. is the general partner of BSOF Parallel Master Fund L.P. Blackstone Holdings II L.P. is the sole member of Blackstone Strategic Opportunity Associates L.L.C. Blackstone Alternative Solutions L.L.C. is the investment manager of BSOF Parallel Master Fund L.P. Blackstone Holdings I L.P. is the sole member of Blackstone Alternative Solutions L.L.C. The general partner of each of Blackstone Holdings I L.P. and Blackstone Holdings II L.P. is Blackstone Holdings I/II GP L.L.C. The sole member of Blackstone Holdings I/II GP L.L.C. is The Blackstone Group Inc. The sole holder of the Class C common stock of The Blackstone Group Inc. is Blackstone Group Management L.L.C. Blackstone Group Management L.L.C. is wholly-owned by Blackstone's senior managing directors and controlled by its founder, Stephen A. Schwarzman. Information with respect to each of the Reporting Persons is given solely by such Reporting Person, and no Reporting Person has responsibility for the accuracy or completeness of information supplied by another Reporting Person. Due to the limitations of the electronic filing system certain Reporting Persons are filing a separate Form 4. Each of the Reporting Persons (other than to the extent it directly holds securities reported herein) disclaims beneficial ownership of the securities held by the other Reporting Persons, except to the extent of such Reporting Person's pecuniary interest therein, and, pursuant to Rule 16a-1(a)(4) under the Securities Exchange Act of 1934, each of the Reporting Persons (other than to the extent it directly holds securities reported herein) states that the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of all of the reported securities for purposes of Section 16 or for any other purpose. BSOF PARALLEL MASTER FUND L.P., By: Blackstone Strategic Opportunity Associates L.L.C., its general partner, By: /s/ Peter Koffler, Name: Peter Koffler, Title: Authorized Signatory 2020-10-22 BLACKSTONE STRATEGIC OPPORTUNITY ASSOCIATES L.L.C., By: /s/ Peter Koffler, Name: Peter Koffler, Title: Authorized Signatory 2020-10-22 BLACKSTONE ALTERNATIVE SOLUTIONS L.L.C. By: /s/ Peter Koffler, Name: Peter Koffler, Title: Authorized Signatory 2020-10-22