X0508 4 2025-11-20 0 0001689548 Praxis Precision Medicines, Inc. PRAX 0001827639 Mastrocola Lauren C/O PRAXIS PRECISION MEDICINES, INC. 99 HIGH STREET, 30TH FLOOR BOSTON MA 02110 0 1 0 0 Principal Accounting Officer 0 Common Stock 2025-11-20 4 M 0 1047 49.50 A 11488.656 D Common Stock 2025-11-20 4 M 0 508 83.85 A 11996.656 D Common Stock 2025-11-20 4 M 0 1557 133.65 A 13553.656 D Common Stock 2025-11-20 4 M 0 2680 43.37 A 16233.656 D Common Stock 2025-11-20 4 M 0 207 44.40 A 16440.656 D Common Stock 2025-11-20 4 M 0 2351 44.40 A 18791.656 D Common Stock 2025-11-20 4 M 0 5250 56.94 A 24041.656 D Common Stock 2025-11-20 4 S 0 11455 191.958 D 12586.656 D Common Stock 2025-11-20 4 S 0 2145 192.711 D 10441.656 D Stock Option (Right to Buy) 49.50 2025-11-20 4 M 0 1047 0.00 D 2029-09-23 Common Stock 1047 0 D Stock Option (Right to Buy) 83.85 2025-11-20 4 M 0 508 0.00 D 2030-06-04 Common Stock 508 0 D Stock Option (Right to Buy) 133.65 2025-11-20 4 M 0 1557 0.00 D 2030-09-13 Common Stock 1557 0 D Stock Option (Right to Buy) 43.37 2025-11-20 4 M 0 2680 0.00 D 2034-01-12 Common Stock 2680 9320 D Stock Option (Right to Buy) 44.40 2025-11-20 4 M 0 207 0.00 D 2023-01-12 2033-01-12 Common Stock 207 0 D Stock Option (Right to Buy) 44.40 2025-11-20 4 M 0 2351 0.00 D 2033-01-12 Common Stock 2351 981 D Stock Option (Right to Buy) 56.94 2025-11-20 4 M 0 5250 0.00 D 2034-07-29 Common Stock 5250 11376 D The price reported is a weighted average price. The securities were sold in multiple transactions at per share prices ranging from $191.500 to $192.432. The Reporting Person undertakes to provide upon request from the SEC staff, the Issuer, or any shareholder of the Issuer, full information regarding the number of securities sold at each separate price within the range set forth in this footnote. The price reported is a weighted average price. The securities were sold in multiple transactions at per share prices ranging from $192.552 to $193.109. The Reporting Person undertakes to provide upon request from the SEC staff, the Issuer, or any shareholder of the Issuer, full information regarding the number of securities sold at each separate price within the range set forth in this footnote. This option was fully vested as of January 1, 2023. This option was fully vested as of May 28, 2024. This option was fully vested as of September 8, 2024. The shares underlying this stock option vested as to 50% on January 12, 2024 and the remaining 50% vesting over a four-year period, with 25% of such shares vesting on January 12, 2025 and the remaining vesting in substantially equal monthly installments over the following 36 months, subject to the Reporting Person's continued service through each vesting date. The shares underlying this stock option vested as to 25% on January 12, 2024 and the remaining shares vest in substantially equal monthly installments over the following 36 months, subject to the Reporting Person's continued service through each vesting date. The shares underlying this stock option vested as to 7/48ths on July 29, 2024 and the remaining shares vest in substantially equal monthly installments over the following 41 months, subject to the Reporting Person's continued service through each vesting date. The transactions reported in this Form 4 were effected for estate planning purposes. /s/ Alex Nemiroff, as Attorney-in-Fact 2025-11-21