# EDGAR Filing Document

**Accession Number:** 0001395937
**File Stem:** 0001193125-23-038098
**Filing Date:** 2023-2
**Character Count:** 61944
**Document Hash:** 896dc43ed3c0bd291e4fc1a591f134e0
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-23-038098.hdr.sgml**: 20230214

**ACCESSION NUMBER**: 0001193125-23-038098

**CONFORMED SUBMISSION TYPE**: SC 13G/A

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20230214

**DATE AS OF CHANGE**: 20230214

**GROUP MEMBERS**: ALBERT CHA

**GROUP MEMBERS**: DANIEL ESTES

**GROUP MEMBERS**: FHMLS X, L.L.C.

**GROUP MEMBERS**: FHMLS X, L.P.

**GROUP MEMBERS**: FHMLS XI, L.L.C.

**GROUP MEMBERS**: FHMLS XI, L.P.

**GROUP MEMBERS**: FHMLSP OVERAGE, L.L.C.

**GROUP MEMBERS**: FHMLSP OVERAGE, L.P.

**GROUP MEMBERS**: FHMLSP, L.L.C.

**GROUP MEMBERS**: FHMLSP, L.P.

**GROUP MEMBERS**: FRAZIER LIFE SCIENCES PUBLIC OVERAGE FUND, L.P.

**GROUP MEMBERS**: FRAZIER LIFE SCIENCES X, L.P.

**GROUP MEMBERS**: FRAZIER LIFE SCIENCES XI, L.P.

**GROUP MEMBERS**: JAMES BRUSH

**GROUP MEMBERS**: JAMES N. TOPPER

**GROUP MEMBERS**: PATRICK J. HERON

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Syndax Pharmaceuticals Inc
- **CENTRAL INDEX KEY:** 0001395937
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **IRS NUMBER:** 320162505
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SC 13G/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-89449
- **FILM NUMBER:** 23625338

**BUSINESS ADDRESS:**
- **STREET 1:** 35 GATEHOUSE DRIVE
- **STREET 2:** BUILDING D, FLOOR 3
- **CITY:** WALTHAM
- **STATE:** MA
- **ZIP:** 02451
- **BUSINESS PHONE:** 781-419-1400

**MAIL ADDRESS:**
- **STREET 1:** 35 GATEHOUSE DRIVE
- **STREET 2:** BUILDING D, FLOOR 3
- **CITY:** WALTHAM
- **STATE:** MA
- **ZIP:** 02451
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Frazier Life Sciences Public Fund, L.P.
- **CENTRAL INDEX KEY:** 0001863769
- **IRS NUMBER:** 862999645
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SC 13G/A

**BUSINESS ADDRESS:**
- **STREET 1:** TWO UNION SQUARE, 601 UNION ST.
- **STREET 2:** SUITE 3200
- **CITY:** SEATTLE
- **STATE:** WA
- **ZIP:** 98101
- **BUSINESS PHONE:** 650-325-5156

**MAIL ADDRESS:**
- **STREET 1:** TWO UNION SQUARE, 601 UNION ST.
- **STREET 2:** SUITE 3200
- **CITY:** SEATTLE
- **STATE:** WA
- **ZIP:** 98101

------

------

**SECURITIES AND EXCHANGE COMMISSION** 

**WASHINGTON, DC 20549** 

------

**SCHEDULE 13G** 

**Under the Securities Exchange Act of 1934** 

**(Amendment No. 1)\*** 

------

## Syndax Pharmaceuticals, Inc.
**(Name of Issuer)** 

**Common Stock** 

**(Title of Class of Securities)** 

**87164F105** 

**(CUSIP Number)** 

**December 31, 2022** 

**(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*).

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; Frazier Life Sciences Public Fund, L.P.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,401,503 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,401,503 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 2,401,503 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 3.5% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; PN

(1) Consists of 2,401,503 shares of Common Stock held directly by Frazier Life Sciences Public Fund, L.P.
FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund, L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore
share voting and investment power over the shares held by Frazier Life Sciences Public Fund, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; FHMLSP, L.P.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,401,503 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,401,503 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 2,401,503 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 3.5% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; PN

(1) Consists of 2,401,503 shares of Common Stock held directly by Frazier Life Sciences Public Fund, L.P.
FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund, L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore
share voting and investment power over the shares held by Frazier Life Sciences Public Fund, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; FHMLSP, L.L.C.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,401,503 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,401,503 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 2,401,503 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 3.5% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; OO

(1) Consists of 2,401,503 shares of Common Stock held directly by Frazier Life Sciences Public Fund, L.P.
FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund, L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore
share voting and investment power over the shares held by Frazier Life Sciences Public Fund, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; Frazier Life Sciences Public Overage Fund, L.P.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;80,800 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;80,800 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 80,800 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 0.1% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; PN

(1) Consists of 80,800 shares of Common Stock held directly by Frazier Life Sciences Public Overage Fund, L.P.
FHMLSP Overage, L.P. is the general partner of Frazier Life Sciences Public Overage Fund, L.P. and FHMLSP Overage, L.L.C. is the general partner of FHMLSP Overage, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of
FHMLSP Overage, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Overage Fund, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; FHMLSP Overage, L.P.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;80,800 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;80,800 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 80,800 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 0.1% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; PN

(1) Consists of 80,800 shares of Common Stock held directly by Frazier Life Sciences Public Overage Fund, L.P.
FHMLSP Overage, L.P. is the general partner of Frazier Life Sciences Public Overage Fund, L.P. and FHMLSP Overage, L.L.C. is the general partner of FHMLSP Overage, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of
FHMLSP Overage, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Overage Fund, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; FHMLSP Overage, L.L.C.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;80,800 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;80,800 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 80,800 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 0.1% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; OO

(1) Consists of 80,800 shares of Common Stock held directly by Frazier Life Sciences Public Overage Fund, L.P.
FHMLSP Overage, L.P. is the general partner of Frazier Life Sciences Public Overage Fund, L.P. and FHMLSP Overage, L.L.C. is the general partner of FHMLSP Overage, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of
FHMLSP Overage, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Overage Fund, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; Frazier Life Sciences XI, L.P.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;38,400 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;38,400 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 38,400 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 0.1% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; PN

(1) Consists of 38,400 shares of Common Stock held directly by Frazier Life Sciences XI, L.P. FHMLS XI, L.P.
is the general partner of Frazier Life Sciences XI, L.P. and FHMLS XI, L.L.C. is the general partner of FHMLS XI, L.P. Patrick J. Heron, James N. Topper and Daniel Estes are the members of FHMLS XI, L.L.C. and therefore share voting and investment
power over the shares held by Frazier Life Sciences XI, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; FHMLS XI, L.P.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;38,400 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;38,400 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 38,400 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 0.1% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; PN

(1) Consists of 38,400 shares of Common Stock held directly by Frazier Life Sciences XI, L.P. FHMLS XI, L.P.
is the general partner of Frazier Life Sciences XI, L.P. and FHMLS XI, L.L.C. is the general partner of FHMLS XI, L.P. Patrick J. Heron, James N. Topper and Daniel Estes are the members of FHMLS XI, L.L.C. and therefore share voting and investment
power over the shares held by Frazier Life Sciences XI, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; FHMLS XI, L.L.C.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;38,400 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;38,400 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 38,400 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 0.1% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; OO

(1) Consists of 38,400 shares of Common Stock held directly by Frazier Life Sciences XI, L.P. FHMLS XI, L.P.
is the general partner of Frazier Life Sciences XI, L.P. and FHMLS XI, L.L.C. is the general partner of FHMLS XI, L.P. Patrick J. Heron, James N. Topper and Daniel Estes are the members of FHMLS XI, L.L.C. and therefore share voting and investment
power over the shares held by Frazier Life Sciences XI, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; Frazier Life Sciences X, L.P.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;1,188,135 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;1,188,135 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 1,188,135 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 1.7% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; PN

(1) Consists of 1,188,135 shares of Common Stock held directly by Frazier Life Sciences X, L.P. FHMLS X,
L.P. is the general partner of Frazier Life Sciences X, L.P. and FHMLS X, L.L.C. is the general partner of FHMLS X, L.P. Patrick J. Heron and James N. Topper are the members of FHMLS X, L.L.C. and therefore share voting and investment power over the
shares held by Frazier Life Sciences X, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; FHMLS X, L.P.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;1,188,135 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;1,188,135 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 1,188,135 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 1.7% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; PN

(1) Consists of 1,188,135 shares of Common Stock held directly by Frazier Life Sciences X, L.P. FHMLS X,
L.P. is the general partner of Frazier Life Sciences X, L.P. and FHMLS X, L.L.C. is the general partner of FHMLS X, L.P. Patrick J. Heron and James N. Topper are the members of FHMLS X, L.L.C. and therefore share voting and investment power over the
shares held by Frazier Life Sciences X, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; FHMLS X, L.L.C.

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; Delaware

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;1,188,135 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;1,188,135 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 1,188,135 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 1.7% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; OO

(1) Consists of 1,188,135 shares of Common Stock held directly by Frazier Life Sciences X, L.P. FHMLS X,
L.P. is the general partner of Frazier Life Sciences X, L.P. and FHMLS X, L.L.C. is the general partner of FHMLS X, L.P. Patrick J. Heron and James N. Topper are the members of FHMLS X, L.L.C. and therefore share voting and investment power over the
shares held by Frazier Life Sciences X, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; James N. Topper

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; United States
Citizen

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;3,708,838 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;3,708,838 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 3,708,838 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 5.4% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; IN

(1) Consists of (i) 2,401,503 shares of Common Stock held directly by Frazier Life Sciences Public Fund,
L.P., (ii) 80,800 shares of Common Stock held directly by Frazier Life Sciences Public Overage Fund, L.P., (iii) 38,400 shares of Common Stock held directly by Frazier Life Sciences XI, L.P. and (iv) 1,188,135 shares of Common
Stock held directly by Frazier Life Sciences X, L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund, L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James
Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund, L.P. FHMLSP Overage, L.P. is the general partner of Frazier Life Sciences Public Overage Fund, L.P.
and FHMLSP Overage, L.L.C. is the general partner of FHMLSP Overage, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP Overage, L.L.C. and therefore share voting and investment power over the shares held by
Frazier Life Sciences Public Overage Fund, L.P. FHMLS XI, L.P. is the general partner of Frazier Life Sciences XI, L.P. and FHMLS XI, L.L.C. is the general partner of FHMLS XI, L.P. Patrick J. Heron, James N. Topper and Daniel Estes are the members
of FHMLS XI, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences XI, L.P. FHMLS X, L.P. is the general partner of Frazier Life Sciences X, L.P. and FHMLS X, L.L.C. is the general partner of FHMLS X,
L.P. Patrick J. Heron and James N. Topper are the members of FHMLS X, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences X, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; Patrick J. Heron

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; United States
Citizen

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;3,708,838 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;3,708,838 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 3,708,838 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 5.4% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; IN

(1) Consists of (i) 2,401,503 shares of Common Stock held directly by Frazier Life Sciences Public Fund,
L.P., (ii) 80,800 shares of Common Stock held directly by Frazier Life Sciences Public Overage Fund, L.P., (iii) 38,400 shares of Common Stock held directly by Frazier Life Sciences XI, L.P. and (iv) 1,188,135 shares of Common
Stock held directly by Frazier Life Sciences X, L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund, L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James
Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund, L.P. FHMLSP Overage, L.P. is the general partner of Frazier Life Sciences Public Overage Fund, L.P.
and FHMLSP Overage, L.L.C. is the general partner of FHMLSP Overage, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP Overage, L.L.C. and therefore share voting and investment power over the shares held by
Frazier Life Sciences Public Overage Fund, L.P. FHMLS XI, L.P. is the general partner of Frazier Life Sciences XI, L.P. and FHMLS XI, L.L.C. is the general partner of FHMLS XI, L.P. Patrick J. Heron, James N. Topper and Daniel Estes are the members
of FHMLS XI, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences XI, L.P. FHMLS X, L.P. is the general partner of Frazier Life Sciences X, L.P. and FHMLS X, L.L.C. is the general partner of FHMLS X,
L.P. Patrick J. Heron and James N. Topper are the members of FHMLS X, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences X, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; Albert Cha

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; United States
Citizen

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,482,303 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,482,303 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 2,482,303 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 3.6% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; IN

(1) Consists of (i) 2,401,503 shares of Common Stock held directly by Frazier Life Sciences Public Fund,
L.P. and (ii) 80,800 shares of Common Stock held directly by Frazier Life Sciences Public Overage Fund, L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund, L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP,
L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund, L.P. FHMLSP Overage, L.P. is the general
partner of Frazier Life Sciences Public Overage Fund, L.P. and FHMLSP Overage, L.L.C. is the general partner of FHMLSP Overage, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP Overage, L.L.C. and
therefore share voting and investment power over the shares held by Frazier Life Sciences Public Overage Fund, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; James Brush

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; United States
Citizen

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,482,303 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;2,482,303 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 2,482,303 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 3.6% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; IN

(1) Consists of (i) 2,401,503 shares of Common Stock held directly by Frazier Life Sciences Public Fund,
L.P. and (ii) 80,800 shares of Common Stock held directly by Frazier Life Sciences Public Overage Fund, L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund, L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP,
L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund, L.P. FHMLSP Overage, L.P. is the general
partner of Frazier Life Sciences Public Overage Fund, L.P. and FHMLSP Overage, L.L.C. is the general partner of FHMLSP Overage, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP Overage, L.L.C. and
therefore share voting and investment power over the shares held by Frazier Life Sciences Public Overage Fund, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

**CUSIP No. 87164F105** 

1. &nbsp;&nbsp;&nbsp;&nbsp; Names of Reporting Persons &nbsp;&nbsp;&nbsp;&nbsp; Daniel Estes

2. &nbsp;&nbsp;&nbsp;&nbsp; Check the Appropriate Box
if a Member of a Group (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; (a) ☐ (b) ☒

3. &nbsp;&nbsp;&nbsp;&nbsp; SEC USE ONLY

4. &nbsp;&nbsp;&nbsp;&nbsp; Citizenship or Place of
Organization &nbsp;&nbsp;&nbsp;&nbsp; United States
Citizen

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 5. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 6. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Voting Power<br>&nbsp;&nbsp;&nbsp;&nbsp;38,400 shares (1) |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 7. | &nbsp;&nbsp;&nbsp;&nbsp;Sole Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;0 shares |
| &nbsp;&nbsp;&nbsp; Number of<br> Shares<br> Beneficially <br> Owned by<br> Each<br> Reporting<br> Person<br> With: | 8. | &nbsp;&nbsp;&nbsp;&nbsp;Shared Dispositive Power<br>&nbsp;&nbsp;&nbsp;&nbsp;38,400 shares (1) |

---

9. &nbsp;&nbsp;&nbsp;&nbsp; Aggregate Amount Beneficially Owned by Each Reporting Person &nbsp;&nbsp;&nbsp;&nbsp; 38,400 shares (1)

10. &nbsp;&nbsp;&nbsp;&nbsp; Check if the Aggregate
Amount in Row (9) Excludes Certain Shares (see instructions) &nbsp;&nbsp;&nbsp;&nbsp; ☐

11. &nbsp;&nbsp;&nbsp;&nbsp; Percent of
Class Represented by Amount in Row 9 &nbsp;&nbsp;&nbsp;&nbsp; 0.1% (2)

12. &nbsp;&nbsp;&nbsp;&nbsp; Type of Reporting Person
(see instructions) &nbsp;&nbsp;&nbsp;&nbsp; IN

(1) Consists of 38,400 shares of Common Stock held directly by Frazier Life Sciences XI, L.P. FHMLS XI, L.P.
is the general partner of Frazier Life Sciences XI, L.P. and FHMLS XI, L.L.C. is the general partner of FHMLS XI, L.P. Patrick J. Heron, James N. Topper and Daniel Estes are the members of FHMLS XI, L.L.C. and therefore share voting and investment
power over the shares held by Frazier Life Sciences XI, L.P.

(2) Based on 68,100,918 shares of Common Stock outstanding as of December 14, 2022 as described in the
Issuer's Current Form 8-K filed with the SEC on December 14, 2022.

------

---

| | |
|:---|:---|
| **Item 1(a).** | Name of Issuer: Syndax Pharmaceuticals, Inc. |
| **Item 1(b).** | Address of Issuer's Principal Executive Offices: 35 Gatehouse Drive, Building D, Floor 3, Waltham, Massachusetts 02451 |
| **Item 2(a).** | Name of Person Filing:<br>The entities and persons filing this statement (collectively, the "Reporting Persons") are:<br>Frazier Life Sciences Public Fund, L.P. ("FLSPF")<br> FHMLSP, L.P.<br> FHMLSP, L.L.C.<br> Frazier Life Sciences Public Overage Fund, L.P. ("FLSPOF")<br> FHMLSP Overage, L.P.<br> FHMLSP Overage, L.L.C.<br> Frazier Life Sciences XI, L.P. ("FLS XI")<br> FHMLS XI, L.P.<br> FHMLS XI, L.L.C.<br> Frazier Life Sciences X, L.P. ("FLS X")<br> FHMLS X, L.P.<br> FHMLS X, L.L.C.<br> James N. Topper ("Topper")<br> Patrick J. Heron ("Heron")<br> Albert Cha ("Cha")<br> James Brush ("Brush")<br> Daniel Estes ("Estes" and together with Topper, Heron, Cha and Brush, the "Members") |
| **Item 2(b).** | Address of Principal Business Office or, if none, Residence:<br>The address and principal business office of the Reporting Persons is:<br>c/o Frazier Life Sciences Management, L.P.<br> 70 Willow Road, Suite 200<br> Menlo Park, CA 94025 |
| **Item 2(c).** | Citizenship: |

---

---

| | | |
|:---|:---|:---|
| Entities: | FLSPF | Delaware, U.S.A. |
|  | FHMLSP, L.P. | Delaware, U.S.A. |
|  | FHMLSP, L.L.C. | Delaware, U.S.A. |
|  | FLSPOF | Delaware, U.S.A. |
|  | FHMLSP Overage, L.P. | Delaware, U.S.A. |
|  | FHMLSP, L.L.C. | Delaware, U.S.A. |
|  | FLS XI | Delaware, U.S.A. |
|  | FHMLS XI, L.P. | Delaware, U.S.A. |
|  | FHMLS XI, L.L.C. | Delaware, U.S.A. |
|  | FLS X | Delaware, U.S.A. |
|  | FHMLS X, L.P. | Delaware, U.S.A. |
|  | FHMLS X, L.L.C. | Delaware, U.S.A. |
| Individuals: | Topper | United States Citizen |
|  | Heron | United States Citizen |
|  | Cha | United States Citizen |
|  | Brush | United States Citizen |
|  | Estes | United States Citizen |

---

---

| | |
|:---|:---|
| **Item 2(d).** | Title of Class of Securities: Common Stock |
| **Item 2(e).** | CUSIP Number: 87164F105 |

---

------

**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:

---

| | |
|:---|:---|
| (a) | ☐ Broker or dealer registered under Section 15 of the Act (15 U.S.C. 78o); |
| (b) | ☐ Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c); |
| (c) | ☐ Insurance company as defined in section 3(a)19) of the Act (15 U.S.C. 78c); |
| (d) | ☐ Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8); |
| (e) | ☐ An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E); |
| (f) | ☐ An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F); |
| (g) | ☐ A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G); |
| (h) | ☐ A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813); |
| (i) | ☐ A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3); |
| (j) | ☐ A non-U.S. institution in accordance with §240.13d–1(b)(1)(ii)(J); |
| (k) | ☐ Group, in accordance with §240.13d–1(b)(1)(ii)(K). |
|  | If filing as a non-U.S. institution in accordance with §240.13d–1(b)(1)(ii)(J), please specify the type of institution: ____ |

---

**Item 4.** **Ownership** <br>

Provide the following information regarding the aggregate number and percentage of the class of securities of the Issuer identified in Item 1.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(a)** Amount Beneficially Owned: See Row 9 of cover page for each Reporting Person.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(b)** Percent of Class: See Row 11 of cover page for each Reporting Person

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(c)** Number of shares as to which the person has:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(i)** Sole power to vote or to direct the vote: See Row 5 of cover page for each Reporting Person.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(ii)** Shared power to vote or to direct the vote: See Row 6 of cover page for each Reporting Person.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(iii)** Sole power to dispose or to direct the disposition of: See Row 7 of cover page for each Reporting
Person.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(iv)** Shared power to dispose or to direct the disposition of: See Row 8 of cover page for each Reporting
Person.

**Item 5.** **Ownership of 5 Percent or Less of a Class** <br>

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than 5 percent of the class of securities, check the following ☐.

**Item 6.** **Ownership of More than 5 Percent on Behalf of Another Person** <br>

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.** <br>

Not applicable.

**Item 8.** **Identification and Classification of Members of the Group** <br>

Each member of the group is identified on Exhibit A to this Schedule 13G amendment.

**Item 9.** **Notice of Dissolution of a Group** <br>

Not applicable.

**Item 10.** **Certification** <br>

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.

------

**SIGNATURE** 

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

---

| | |
|:---|:---|
| Date: February 14, 2023 | **FRAZIER LIFE SCIENCES PUBLIC FUND, L.P.** |
|  | By: FHMLSP, L.P., its General Partner |
|  | By: FHMLSP, L.L.C., its General Partner |
|  | /s/ Steve R. Bailey |
|  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLSP, L.P.** |
|  | By: FHMLSP, L.L.C., its General Partner |
|  | /s/ Steve R. Bailey |
|  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLSP, L.L.C.** |
|  | /s/ Steve R. Bailey |
|  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FRAZIER LIFE SCIENCES PUBLIC OVERAGE FUND, L.P.** |
|  | By: FHMLSP Overage, L.P., its General Partner |
|  | By: FHMLSP Overage, L.L.C., its General Partner |
|  | /s/ Steve R. Bailey |
|  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLSP OVERAGE, L.P.** |
|  | By FHMLSP Overage, L.L.C., its General Partner |
|  | /s/ Steve R. Bailey |
|  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLSP OVERAGE, L.L.C.** |
|  | /s/ Steve R. Bailey |
|  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FRAZIER LIFE SCIENCES XI, L.P.** |
|  | By: FHMLS XI, L.P., its General Partner |
|  | By: FHMLS XI, L.L.C., its General Partner |
|  | /s/ Steve R. Bailey |
|  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLS XI, L.P.** |
|  | By: FHMLS XI, L.L.C., its General Partner |
|  | /s/ Steve R. Bailey |
|  | Steve R. Bailey, Chief Financial Officer |

---

------

---

| | | |
|:---|:---|:---|
| Date: February 14, 2023 | **FHMLS XI, L.L.C.** | **FHMLS XI, L.L.C.** |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FRAZIER LIFE SCIENCES X, L.P.** | **FRAZIER LIFE SCIENCES X, L.P.** |
|  | By: FHMLS X, L.P., its General Partner | By: FHMLS X, L.P., its General Partner |
|  | By: FHMLS X, L.L.C., its General Partner | By: FHMLS X, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLS X, L.P.** | **FHMLS X, L.P.** |
|  | By: FHMLS X, L.L.C., its General Partner | By: FHMLS X, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLS X, L.L.C.** | **FHMLS X, L.L.C.** |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | By: | \* |
|  |  | James N. Topper |
| Date: February 14, 2023 | By: | \* |
|  |  | Patrick J. Heron |
| Date: February 14, 2023 | By: | \*\* |
|  |  | Albert Cha |
| Date: February 14, 2023 | By: | \*\* |
|  |  | James Brush |
| Date: February 14, 2023 | By: | \*\*\* |
|  |  | Daniel Estes |
| Date: February 14, 2023 | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, as Attorney-in-Fact |

---

\* This Schedule 13G was executed by Steve R. Bailey on behalf of the individuals listed above pursuant to a Power of Attorney, a copy of which was filed with the SEC on March 29, 2016.

\*\* This Schedule 13G was executed by Steve R. Bailey on behalf of the individuals listed above pursuant to a Power of Attorney, a copy of which was filed with the SEC on August 16, 2021.

\*\*\* This Schedule 13G was executed by Steve R. Bailey on behalf of the individual listed above pursuant to a Power of Attorney, a copy of which was filed with the SEC on April 18, 2022.

------

**Exhibit Index** 

Exhibit A - Agreement regarding filing of joint Schedule 13G.

## Ex-99.A

**EXHIBIT A** 

**AGREEMENT** 

Pursuant to Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, the undersigned hereby agree that only one statement containing the information required by Schedule 13G need be filed with respect to the ownership by each of the undersigned of Common Stock of Syndax Pharmaceuticals, Inc.

---

| | | |
|:---|:---|:---|
| Date: February 14, 2023 | **FRAZIER LIFE SCIENCES PUBLIC FUND, L.P.** | **FRAZIER LIFE SCIENCES PUBLIC FUND, L.P.** |
|  | By: | FHMLSP, L.P., its General Partner |
|  | By: | FHMLSP, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLSP, L.P.** | **FHMLSP, L.P.** |
|  | By: | FHMLSP, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLSP, L.L.C.** | **FHMLSP, L.L.C.** |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FRAZIER LIFE SCIENCES PUBLIC OVERAGE FUND, L.P.** | **FRAZIER LIFE SCIENCES PUBLIC OVERAGE FUND, L.P.** |
|  | By: | FHMLSP Overage, L.P., its General Partner |
|  | By: | FHMLSP Overage, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLSP OVERAGE, L.P.** | **FHMLSP OVERAGE, L.P.** |
|  | By | FHMLSP Overage, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLSP OVERAGE, L.L.C.** | **FHMLSP OVERAGE, L.L.C.** |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FRAZIER LIFE SCIENCES XI, L.P.** | **FRAZIER LIFE SCIENCES XI, L.P.** |
|  | By: | FHMLS XI, L.P., its General Partner |
|  | By: | FHMLS XI, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |

---

------

---

| | | |
|:---|:---|:---|
| Date: February 14, 2023 | **FHMLS XI, L.P.** | **FHMLS XI, L.P.** |
|  | By: | FHMLS XI, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLS XI, L.L.C.** | **FHMLS XI, L.L.C.** |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FRAZIER LIFE SCIENCES X, L.P.** | **FRAZIER LIFE SCIENCES X, L.P.** |
|  | By: | FHMLS X, L.P., its General Partner |
|  | By: | FHMLS X, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLS X, L.P.** | **FHMLS X, L.P.** |
|  | By: | FHMLS X, L.L.C., its General Partner |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | **FHMLS X, L.L.C.** | **FHMLS X, L.L.C.** |
|  | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, Chief Financial Officer |
| Date: February 14, 2023 | By: | \* |
|  |  | James N. Topper |
| Date: February 14, 2023 | By: | \* |
|  |  | Patrick J. Heron |
| Date: February 14, 2023 | By: | \*\* |
|  |  | Albert Cha |
| Date: February 14, 2023 | By: | \*\* |
|  |  | James Brush |
| Date: February 14, 2023 | By: | \*\*\* |
|  |  | Daniel Estes |
| Date: February 14, 2023 | By: | /s/ Steve R. Bailey |
|  |  | Steve R. Bailey, as Attorney-in-Fact |

---

\* This Agreement was executed by Steve R. Bailey on behalf of the individuals listed above pursuant to a Power of Attorney, a copy of which was filed with the SEC on March 29, 2016.

\*\* This Agreement was executed by Steve R. Bailey on behalf of the individuals listed above pursuant to a Power of Attorney, a copy of which was filed with the SEC on August 16, 2021.

\*\*\* This Agreement was executed by Steve R. Bailey on behalf of the individuals listed above pursuant to a Power of Attorney, a copy of which was filed with the SEC on April 18, 2022.