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): February 18, 2023

ACTINIUM PHARMACEUTICALS, INC.
(Exact name of registrant as specified in its charter)

275 Madison Avenue, 7th Floor, New York, NY 10016

(Address of Principal Executive Offices)

Registrant’s telephone number: (646) 677-3870

(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):

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

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 7.01 Regulation FD Disclosure.

On February 18, 2023, Actinium Pharmaceuticals, Inc. (the “Company”), announced that Iomab-B met the primary endpoint of the pivotal Phase 3 SIERRA trial producing higher rates of durable Complete Remission (“dCR”) 6-months following initial complete remission after bone marrow transplant (“BMT”) with high statistical significance (p<0.0001). Iomab-B also significantly improved event-free survival (“EFS”), a secondary endpoint of the SIERRA trial, for which Iomab-B produced a 78% lower probability of an event resulting an EFS Hazard Ratio=0.22 (p<0.0001). Patients receiving Iomab-B had a 100% increase in 1-year overall survival (“OS”) and median OS compared to patients on the control arm. Overall survival is a secondary endpoint of the SIERRA trial, but the crossover arm of the SIERRA trial confounds statistics. Patients receiving Iomab-B who reached 6-month dCR had long-term survival outcomes with 92% 1-year OS and 60 2-year OS. Iomab-B was well tolerated based on the targeted nature, resulting in four times lower rates of sepsis in patients receiving Iomab-B compared to the control arm and clinically meaningful lower rate of graft versus host disease (“GVHD”).

These results were presented at the 2023 Tandem Meetings: Transplantation and Cellular Therapy Meetings of the American Society for Transplantation and Cellular Therapy (ASTCT) and the Center for International Blood & Marrow Transplant Research (CIBMTR) in a late-breaker presentation on Saturday, February 18, 2023. Also on February 18, 2023, the Company hosted an investor conference call and presented the results of the SIERRA trial as well as the potential market and commercial opportunity for Iomab-B.

The Company issued a press release detailing these results, a copy of which is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated by reference herein. The Company also made an investor presentation detailing the same results, a copy of which is furnished as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated by reference herein. The Company undertakes no obligation to update, supplement or amend the materials attached hereto as Exhibit 99.1 and 99.2

In accordance with General Instruction B.2 of Form 8-K, the information in this Item 7.01 of this Current Report on Form 8-K, including Exhibit 99.1 and Exhibit 99.2, shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Exchange Act or the Securities Act of 1933, as amended, except as shall be expressly set forth by reference in such a filing. Furthermore, the furnishing of information under Item 7.01 of this Current Report on Form 8-K is not intended to constitute a determination by the Company that the information contained herein, including the exhibits hereto, is material or that the dissemination of such information is required by Regulation FD.

Item 9.01 Financial Statements and Exhibits

(d) Exhibits.

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.

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