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):   September 27, 2013 (September 24, 2013)

Aastrom Biosciences, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code:   (800) 556-0311

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:

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

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

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

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

Item 1.01. Entry into a Material Definitive Agreement.

On September 24, 2013, Aastrom Biosciences, Inc., a Michigan corporation (the “Company”), entered into a Warrant Exercise Agreement with two holders (the “Holders”) of warrants issued by the Company on August 16, 2013 (the “2013 Warrants”) to purchase an aggregate of 7,333,000 shares of the Company’s common stock, no par value (“Common Stock”).  Pursuant to the Warrant Exercise Agreements, the Holders agreed to exercise the 2013 Warrants at the existing exercise price of $0.375 in exchange for a fee of an aggregate amount of approximately $1,209,945.  The net proceeds to the Company in connection with the exercise of the 2013 Warrants, after deducting estimated expenses, are approximately $1,470,000.  As a result of these transactions, there are now 22,667,000 2013Warrants outstanding and the warrant liability has been reduced by approximately 24%.

The foregoing description of the Warrant Exercise Agreements does not purport to be complete and is qualified in its entirety by reference to the Form of Warrant Exercise Agreement which is filed herewith as Exhibit 10 and incorporated herein by reference.

Item 9.01.  Financial Statements and Exhibits.

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SIGNATURE

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.

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