Washington, D.C. 20549







Pursuant to Section 13 or 15(d)

of The Securities Exchange Act of 1934

Date of Report (Date of Earliest Event Reported): March 4, 2020




(Exact name of registrant as specified in its charter)




Delaware   001-38443   46-5308248

(State or other jurisdiction

of incorporation)



File Number)


(I.R.S. Employer

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200 Cambridge Park Drive, Suite 3100

Cambridge, Massachusetts

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



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


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Common stock, $0.001 Par Value   UMRX   The Nasdaq Global Select Market

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Item 8.01

Other Events.

On March 4, 2020, Unum Therapeutics Inc. (“Unum”) was verbally notified by the U.S. Food & Drug Administration (FDA) that it had placed a partial clinical hold on the Phase 1 trial (ATTCK-20-03) of Unum’s ACTR707 in combination with rituximab in patients with CD20+ B cell non-Hodgkin lymphoma (r/r NHL). The partial clinical hold was initiated following the submission of a safety report by Unum to the FDA regarding one patient in the trial who experienced a Grade 3 serious adverse event that is being evaluated as a possible new malignancy and is considered to be possibly related to ACTR707. Unum plans to work closely with the study site and the FDA to further review this event. Patients who previously received ACTR707 can continue to receive rituximab infusions on study.

Previously, on March 2, 2020, Unum announced a new strategic effort prioritizing and allocating resources towards the advancement of its preclinical program, BOXR1030, for the treatment of advanced solid tumor cancers. As part of the implementation of the new strategic effort, Unum announced that it is concluding its clinical trials of ACTR707, including the Phase 1 trial (ATTCK-20-03) in combination with rituximab in r/r NHL and the Phase 1 trial (ATTCK-34-01) in combination with trastuzumab to treat advanced HER2+ solid tumor cancers.


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.


Date: March 9, 2020     UNUM THERAPEUTICS INC.
    By:   /s/ Charles Wilson
      Charles Wilson, Ph.D.
      Chief Executive Officer and President