Filed Pursuant to Rule 424(b)(3)

Registration No. 333-274931

Prospectus Supplement No. 1

(To Prospectus Dated December 28, 2023)

ESTRELLA IMMUNOPHARMA, INC.

3,829,338 Shares of Common Stock

Up to 7,036,726 Shares of Common Stock

Up to 2,215,000 Shares of Common Stock Issuable Upon Exercise of Warrants

This prospectus supplement and the prospectus dated December 28, 2023 (the “Prospectus”) which forms a part of our registration statement on Form S-1 (No. 333-274931), relate to the offer, sale and resale from time to time of certain shares of common stock (“Common Stock”) of Estrella Immunopharma, Inc. (“we,” “us,” “our” the “Company” and “Estrella”). These shares include (a) 3,829,338 shares of Common Stock held by the Selling Stockholders as more fully described in the Prospectus, (b) up to 7,036,726 shares of Common Stock that may be issued and sold by us to White Lion Capital, LLC pursuant to a Common Stock Purchase Agreement, as more fully described in the Prospectus and (c) up to 2,215,000 shares of Common Stock issuable upon the exercise of redeemable warrants (“Warrants”) at an exercise price of $11.50 per share, as more fully described in the Prospectus.

This prospectus supplement is being filed to update and supplement the information contained in the Prospectus with the information contained in the current reports on Form 8-K filed by the Company on January 30, 2024 and February 2, 2024 (the “Current Reports”). Accordingly, we have attached the Current Reports to this prospectus supplement.

You should read this prospectus supplement in conjunction with the Prospectus, including any amendments or supplements to the Prospectus. This prospectus supplement is qualified by reference to the Prospectus, except to the extent that the information provided by this prospectus supplement supersedes information contained in the Prospectus. This prospectus supplement is not complete without, and may not be delivered or used except in conjunction with, the Prospectus, including any amendments or supplements to the Prospectus. Capitalized terms used in this prospectus supplement but not defined herein have the meanings given to such terms in the Prospectus.

Our Common Stock and Warrants are traded on the Nasdaq Capital Market (“Nasdaq”) under the symbols “ESLA” and “ESLAW,” respectively. On February 9, 2024, the closing price of our Common Stock on Nasdaq was $1.16 per share and the closing price of our Warrants on Nasdaq was $0.0396 per Warrant.

Investing in our securities is highly speculative and involves a high degree of risk. See “Risk Factors” beginning on page 7 of the Prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if the Prospectus or this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is February 12, 2024.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): January 30, 2024

Estrella Immunopharma, Inc.

(Exact name of registrant as specified in its charter)

Delaware	001-40608	86-1314502
(State or other jurisdiction	(Commission File Number)	(IRS Employer
of incorporation)		Identification Number)

5858 Horton Street, Suite 370 Emeryville, California	94608
(Address of principal executive offices)	(Zip Code)

(510) 318-9098

(Registrant’s telephone number, including area code)

N/A

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act.

Title of each class	Trading Symbol	Name of each exchange  on which registered
Common Stock, par value $0.0001 per share	ESLA	The Nasdaq Stock Market LLC
Warrants, each whole warrant exercisable for one share of Common Stock at an exercise price of $11.50	ESLAW	The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933(§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging  growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 8.01 Other Events

On January 30, 2024, Estrella Immunopharma, Inc. issued a press release announcing that its board of directors has authorized share repurchases of up to $1 million of its common stock. The authorization does not constitute a formal or binding commitment to make any share repurchases and the timing, amount and method of any share repurchases made pursuant to the authorization will be determined at a future date depending on market conditions and other factors. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Item 9.01. Financial Statements and Exhibits

(d) Exhibits

Exhibit No.	Description
99.1	Press Release, dated January 30, 2024
104	Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	Estrella Immunopharma, Inc.
	By:	/s/ Cheng Liu
	Name:	Dr. Cheng Liu
	Title:	Chief Executive Officer
Date: January 30, 2024

2

Exhibit 99.1

Estrella Immunopharma Announces $1 Million Share Repurchase Authorization

Emeryville, Jan 30, 2024 — Estrella Immunopharma, Inc. (NASDAQ: ESLA, ESLAW ) (“Estrella Immunopharma” or “Estrella”), a clinical-stage biopharmaceutical company developing CD19 and CD22-targeted ARTEMIS® T-cell therapies with the capacity to address treatment challenges for patients with blood cancers and solid tumors, is pleased to announce that its board of directors has authorized share repurchases of up to $1 million of its common stock.

“The share repurchase authorization underscores Estrella’s commitment to driving shareholder value, as well as management’s confidence in Estrella’s value and long-term potential,” said Dr. Cheng Liu, CEO and Chairman of Estrella.

“The share repurchase authorization reflects confidence in Estrella’s strategic direction and continued development of our innovative therapies,” commented Peter Xu, CFO of Estrella.

The authorization does not constitute a formal or binding commitment to make any share repurchases and the timing, amount and method of any share repurchases made pursuant to the authorization will be determined at a future date depending on market conditions and other factors.

About Estrella Immunopharma

Estrella is a clinical-stage biopharmaceutical company developing CD19 and CD22-targeted ARTEMIS® T-cell therapies with the capacity to address treatment challenges for patients with blood cancers and solid tumors. Estrella’s mission is to harness the evolutionary power of the human immune system to transform the lives of patients fighting cancer. To accomplish this mission, Estrella’s lead product candidate, EB103, utilizes Eureka’s ARTEMIS® technology to target CD19, a protein expressed on the surface of almost all B-cell leukemias and lymphomas. Estrella is also developing EB104, which also utilizes Eureka’s ARTEMIS® technology to target not only CD19, but also CD22, a protein that, like CD19, is expressed on the surface of most B-cell malignancies. Estrella is also collaborating with Imugene Limited and its product candidate, CF33-CD19t an oncolytic virus (“CF33-CD19t”), to research the use of EB103 in conjunction with CF33-CD19t to treat solid tumors using a “mark and kill” strategy. For more information about Estrella Immunopharma, please visit estrellabio.com

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including statements regarding Estrella’s share repurchase authorization, its long-term potential and the continued development of its therapies . These statements may be identified by the use of forward-looking expressions, including, but not limited to, “potential,” “future,” “continued” and similar expressions and the negatives of those terms. These statements relate to future events or future financial performance and involve known and unknown risks, uncertainties, and other factors that could cause actual results, performance, or achievements to differ materially from those expressed or implied by these forward-looking statements. Factors that may cause actual results, performance or achievements to differ materially from current expectations include, among other things, those listed under “Risk Factors” and elsewhere in our filings with the Securities and Exchange Commission. The forward-looking statements in this press release represent our views as of the date of this press release. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law. You should, therefore, not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this press release.

Contact:

Investor Relations

Estrella Immunopharma, Inc.

IR@estrellabio.com

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): January 30, 2024

Estrella Immunopharma, Inc.

(Exact name of registrant as specified in its charter)

Delaware	001-40608	86-1314502
(State or other jurisdiction	(Commission File Number)	(IRS Employer
of incorporation)		Identification Number)

5858 Horton Street, Suite 370 Emeryville, California	94608
(Address of principal executive offices)	(Zip Code)

(510) 318-9098

(Registrant’s telephone number, including area code)

N/A

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act.

Title of each class	Trading Symbol	Name of each exchange  on which registered
Common Stock, par value $0.0001 per share	ESLA	The Nasdaq Stock Market LLC
Warrants, each whole warrant exercisable for one share of Common Stock at an exercise price of $11.50	ESLAW	The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933(§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging  growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 4.01 Changes in Registrant’s Certifying Accountant

(a) Dismissal of Independent Registered Public Accounting Firm

Estrella Immunopharma, Inc. (the “Company”), at the direction of the Board of Directors of the Company (the “Board”), and upon the recommendation of the Audit Committee of the Board, dismissed its independent registered public accountant Marcum LLP (“Marcum”), effective as of January 30, 2024. Marcum was initially engaged on November 3, 2022 by Estrella Biopharma, Inc. (“Estrella”), the Company’s wholly-owned subsidiary and accounting predecessor following the consummation of the business combination between Estrella, Tradeup Merger Sub Inc. and TradeUP Acquisition Corp. on September 29, 2023, to serve as Estrella’s auditor for its fiscal year ended June 30, 2023.

Marcum’s report on Estrella’s financial statements for the fiscal year ended June 30, 2023 did not contain an adverse opinion or a disclaimer of opinion, and was not qualified or modified as to uncertainty, audit scope, or accounting principles, except that Marcum’s report contained an explanatory paragraph expressing substantial doubt about the ability of Estrella to continue as a going concern.

During the fiscal year ended June 30, 2023 and subsequent interim periods through the date of Marcum’s dismissal, there were (i) no disagreements with Marcum on any matter of accounting principles or practices, financial statement disclosure, or auditing scope or procedure, any of which, if not resolved to Marcum’s satisfaction, would have caused it to make reference to the subject matter of any such disagreement in connection with its reports for such years and (ii) no “reportable events” requiring disclosure pursuant to paragraph (a)(1)(v) of Item 304 of Regulation S-K and the related instructions to Item 304 of Regulation S-K.

In accordance with Item 304(a)(3) of Regulation S-K, the Company has provided Marcum a copy of the disclosures it is making in this Current Report on Form 8-K prior to filing with the Securities and Exchange Commission (the “SEC”) and requested that Marcum furnish the Company with a letter addressed to the SEC stating whether or not Marcum agrees with the above statements. A copy of Marcum’s letter, dated February 1, 2024, is filed as Exhibit 16.1 to this Current Report on Form 8-K.

(b) Appointment of New Independent Registered Public Accounting Firm

At the direction of the Board, and upon the recommendation of the Audit Committee, the Company appointed Macias Gini & O’Connell, LLP (“MGO”) as the Company’s new independent registered public accounting firm for the fiscal year ending June 30, 2024, effective as of January 30, 2024. During the Company’s two most recent fiscal years ended June 30, 2022, and June 30, 2023, and the subsequent interim period through the date of MGO’s engagement, neither the Company nor anyone on its behalf has consulted with MGO regarding (i) the application of accounting principles to a specific transaction, either completed or proposed, or the type of audit opinion that might be rendered on the Company’s financial statements, where either a written report or oral advice was provided to the Company that MGO concluded was an important factor considered by the Company in reaching a decision as to the accounting, auditing or financial reporting issue, (ii) any matter that was the subject of a disagreement within the meaning of Item 304(a)(1)(iv) of Regulation S-K and the related instructions to Item 304 of Regulation S-K or (iii) any reportable event within the meaning of Item 304(a)(1)(v) of Regulation S-K.

Item 9.01. Financial Statements and Exhibits

(d) Exhibits

Exhibit No.	Description
16.1	Letter from Marcum LLP, dated February 1, 2024
104	Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	Estrella Immunopharma, Inc.
	By:	/s/ Cheng Liu
	Name:	Dr. Cheng Liu
	Title:	Chief Executive Officer
Date: February 2, 2024

2

Exhibit 16.1

February 1, 2024

Securities and Exchange Commission

100 F Street, N.E.

Washington, DC 20549

Commissioners:

We have read the statements made by Estrella Immunopharma, Inc. under Item 4.01 of its Form 8-K dated January 30, 2024. We agree with the statements concerning our Firm in such Form 8-K; we are not in a position to agree or disagree with other statements of Estrella Immunopharma, Inc. contained therein.

Very truly yours,

/s/ Marcum llp

Marcum llp