Autolus (NASDAQ: AUTL) signs 10-year AGC Biologics lentiviral supply pact

Rhea-AI Filing Summary

Autolus Therapeutics plc filed a prospectus supplement covering the resale by selling securityholders of up to 54,584,250 American Depositary Shares (ADSs), including 3,265,306 ADSs issuable upon exercise of outstanding warrants. The ADSs trade on Nasdaq under the symbol AUTL, and the closing price on January 23, 2026 was $1.46 per ADS.

The supplement also incorporates an 8-K describing a new 10-year Master Supply Agreement between Autolus Limited and AGC Biologics S.p.A for lentiviral vector, a critical raw material for the company’s CAR-T products, including AUCATZYL and clinical trial products. Autolus Limited committed to purchase a minimum of 14 batches of lentiviral vector in the first two calendar years and a minimum value of EUR 25 million of products and services over the subsequent five-year period, under a non-exclusive arrangement that gives AGC a first right to negotiate new manufacturing activities for the obe-cel product.

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Biotech operations and supply-chain analyst

Autolus locks in long-term viral vector supply with minimum purchase commitments.

Autolus Limited, a wholly owned subsidiary of Autolus Therapeutics, entered a 10-year Master Supply Agreement with AGC Biologics S.p.A for lentiviral vector, which is described as critical for manufacturing the company’s CAR-T products, including AUCATZYL and clinical trial materials. The pact is non-exclusive but establishes the general terms for products and services via individual work orders.

The company has committed to buy a minimum of 14 batches of lentiviral vector in the first two calendar years and at least EUR 25 million of products and services over the following five-year period. These minimums help secure supply continuity but also create multi-year purchase obligations whose scale, relative to Autolus’s overall spending, is not detailed in the excerpt.

The agreement runs for ten years and can be terminated for default by either party or by the company on notice subject to certain fees, while AGC receives a first right to negotiate new manufacturing activities for the obe-cel product. Future filings, such as the Form 10-Q for the quarter ending March 31, 2026, may provide the filed agreement text and more granular financial impact.

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Filed pursuant to Rule 424(b)(3)

Registration No. 333-287097

PROSPECTUS SUPPLEMENT NO. 7

(To the prospectus dated May 15, 2025)

Up to 54,584,250 American Depositary Shares Representing 54,584,250 Ordinary Shares Offered by Selling Securityholders

This prospectus supplement supplements the prospectus, dated May 15, 2025 (the “Prospectus”), which forms a part of our registration statement on Form S-1 (No. 333-287097). This prospectus supplement is being filed to update and supplement the information in the Prospectus with the information contained in our Current Report on Form 8-K filed with the Securities and Exchange Commission (the “SEC”) on January 26, 2026 (the “Report”). Accordingly, we have attached the Report to this prospectus supplement.

The Prospectus and this prospectus supplement relate to the resale from time to time by the selling securityholders identified in the Prospectus, of up to 54,584,250 American Depositary Shares, or ADSs, consisting of (i) 51,318,944 ADSs, representing 51,318,944 of our ordinary shares, with a nominal value of $0.000042 per share, and (ii) up to an aggregate of 3,265,306 ADSs issuable upon the exercise of outstanding warrants to purchase our ADSs, representing 3,265,306 ordinary shares.

The ADSs are listed on the Nasdaq Global Select Market, or Nasdaq, under the symbol “AUTL.” On January 23, 2026, the closing sale price of the ADSs on Nasdaq was $1.46.

This prospectus supplement should be read in conjunction with the Prospectus, including any amendments or supplements thereto, which is to be delivered with this prospectus supplement. This prospectus supplement is qualified by reference to the Prospectus, including any amendments or supplements thereto, except to the extent that the information in this prospectus supplement updates and supersedes the information contained therein.

This prospectus supplement is not complete without, and may not be delivered or utilized except in connection with, the Prospectus, including any amendments or supplements thereto.

You should read this prospectus supplement carefully before you invest in our securities. Investing in our securities involves risks. You should consider carefully the risks that we have described under the caption “Risk Factors” on page 6 of the Prospectus and in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, our Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2025 and our other filings with the SEC.

Neither the SEC nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus supplement or the Prospectus. Any representation to the contrary is a criminal offense.

PROSPECTUS SUPPLEMENT DATED JANUARY 26, 2026

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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 21, 2026

Autolus Therapeutics plc

(Exact name of registrant as specified in its Charter)

England and Wales			001-38547						Not applicable
(State or other jurisdiction of incorporation or organization)			(Commission File Number)						(I.R.S. Employer Identification No.)
The Mediaworks
191 Wood Lane
London						W12 7FP
United Kingdom
(Address of principal executive offices)(Zip Code)
(44) 20						3829 6230
(Registrant's telephone number, including area code)
Not Applicable
(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 (see General Instruction A.2. below):

☐			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))

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

Title of each class			Trading Symbol(s)			Name of each exchange on which registered
American Depositary Shares, each representing one ordinary share, nominal value $0.000042 per share			AUTL			The Nasdaq Global Select Market
Ordinary shares, nominal value $0.000042 per share*			*			The Nasdaq Stock Market LLC*

* Not for trading, but only in connection with the listing of the American Depositary Shares on The Nasdaq Global Select Market. The American Depositary Shares represent the right to receive ordinary shares and are being registered under the Securities Act of 1933, as amended, pursuant to a separate Registration Statement on Form F-6. Accordingly, the American Depositary Shares are exempt from the operation of Section 12(a) of the Securities Exchange Act of 1934, as amended, pursuant to Rule 12a-8 thereunder.

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 1.01 Entry into a Material Definitive Agreement

On January 21, 2026, Autolus Limited entered into a Master Supply Agreement with AGC Biologics S.p.A (“AGC”) for the manufacture and supply of lentiviral vector (the “Agreement”). Autolus Limited (the “Company”), being a UK company and a wholly owned subsidiary of Autolus Therapeutics plc (the “registrant”), is the sole manufacturer of all CAR-T products supplied by the registrant’s operational companies globally, including the manufacturer of AUCATZYL commercial product and the manufacturer of clinical trial product. The lentiviral vector manufactured and supplied by AGC to the Company is a raw material which is critical for the manufacture of CAR-T products manufactured by the Company.

The Agreement sets forth the general terms and conditions applicable to AGC’s provision of products and services to the Company; specific projects will be set forth in individual work orders executed separately by the parties. The Agreement contains customary provisions regarding order placement and fulfillment, governance, regulatory support, change management, risk allocation, intellectual property, and confidentiality. The Agreement runs for a fixed term of ten years, and may be terminated by either party for default, or by the Company upon written notice (subject, in the latter case, to the payment of certain fees by the Company). The Agreement is non-exclusive with respect to each party. However, under the Agreement and the initial statement of work thereunder, the Company has committed to purchase a minimum of 14 batches of lentiviral vector during the first two calendar years of the term, and to purchase a minimum value of EUR 25 million of products and services during the subsequent five-year period. The Agreement also provides AGC with the first right to negotiate with the Company regarding the provision of new manufacturing activities in relation to the Company’s obecabtagene autoleucel, or obe-cel, product.

The foregoing summary of the material terms of the Master Service Agreement does not purport to be complete and is qualified in its entirety by reference to such Master Service Agreement, which will be filed as an exhibit to the Company’s Quarterly Report on Form 10-Q for the quarter ending March 31, 2026. Portions of the Agreement may be omitted pursuant to Item 601(b)(10)(iv) or Item 601(a)(5) of Regulation S-K under the Securities Exchange Act of 1934, as amended.

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SIGNATURES

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

						AUTOLUS THERAPEUTICS PLC
Dated: January 26, 2026			By:			/s/Christian Itin, Ph.D.
						Name: Christian Itin, Ph.D.
						Title: Chief Executive Officer

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FAQ

What does Autolus Therapeutics plc (AUTL) register in this prospectus supplement?

The prospectus supplement relates to the resale from time to time by selling securityholders of up to 54,584,250 American Depositary Shares (ADSs), representing the same number of ordinary shares. This includes 51,318,944 ADSs representing existing ordinary shares and up to 3,265,306 ADSs issuable upon exercise of outstanding warrants.

Is Autolus Therapeutics itself selling ADSs in this AUTL filing?

The document states that the Prospectus and this supplement relate to the resale of ADSs by identified selling securityholders. It does not describe Autolus Therapeutics plc as the seller of these securities, focusing instead on holders who may sell from time to time under the registration.

What new agreement did Autolus disclose with AGC Biologics in this filing?

Autolus Limited entered into a Master Supply Agreement with AGC Biologics S.p.A on January 21, 2026 for the manufacture and supply of lentiviral vector. The agreement sets out terms under which AGC will provide products and services to support Autolus’s CAR-T manufacturing operations.

How long is the AGC Biologics supply agreement with Autolus and can it be terminated?

The Master Supply Agreement runs for a fixed term of ten years. It may be terminated by either party for default, and it may be terminated by the company upon written notice, in which case the company must pay certain fees as specified in the agreement.

What minimum purchase commitments does Autolus have under the AGC Master Supply Agreement?

Under the agreement and initial statement of work, Autolus Limited committed to purchase a minimum of 14 batches of lentiviral vector during the first two calendar years of the term and to purchase a minimum value of EUR 25 million of products and services during the subsequent five-year period.

Why is the AGC lentiviral vector supply important for Autolus Therapeutics (AUTL)?

The filing describes lentiviral vector supplied by AGC as a critical raw material for manufacturing the company’s CAR-T products. Autolus Limited is noted as the sole manufacturer of all CAR-T products supplied by Autolus’s operational companies globally, including commercial AUCATZYL and clinical trial products.

What special rights does AGC Biologics receive regarding Autolus’s obe-cel product?

The agreement gives AGC Biologics the first right to negotiate with Autolus Limited for new manufacturing activities related to the company’s obecabtagene autoleucel (obe-cel) product, as described in the filing.