8-K

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): April 8, 2022

MOLECULIN BIOTECH, INC.

(Exact Name of Registrant as Specified in its Charter)

delaware	001-37758	47-4671997
(State or Other Jurisdiction of Incorporation or Organization)	(Commission File No.)	(I.R.S. Employer Identification No.)

5300 Memorial Drive, Suite 950, Houston, TX 77007

(Address of principal executive offices and zip code)

(713) 300-5160

(Registrant’s telephone number, including area code)

(Former name or former address, if changed from 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-14(c)).

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. ☐

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

Title of each class	Trading Symbol (s)	Name of each exchange on which registered
Common Stock, par value $.001 per share	MBRX	The NASDAQ Stock Market LLC

Item 7.01          Regulation FD Disclosure

On April 8, 2022, Moleculin Biotech, Inc. (the “Company”), issued a press release to announce that preclinical data of Annamycin tested in syngeneic models of metastatic colorectal cancer established in lungs or liver was accepted for poster presentation at the American Association for Cancer Research (AACR) Annual Meeting 2022, being held April 8-13, 2022, in New Orleans, Louisiana.

A copy of the press release is attached to this report as Exhibit 99.1 and is incorporated by reference herein.

The information contained in Item 7.01 of this Current Report on Form 8-K, including Exhibit 99.1, is being furnished and shall not be “filed” for the purpose of the Securities Exchange Act of 1934, as amended (“Exchange Act”), nor shall it be incorporated by reference in any filing under the Exchange Act or the Securities Act of 1933, as amended (“Securities Act”), unless specifically identified therein as being incorporated by reference.

Item 9.01          Financial Statements and Exhibits.

(d)         Exhibits.

Exhibit No.         Description

99.1                   Press Release dated April 8, 2022

104                   Cover page Interactive Data File (formatted as Inline XBRL document)

SIGNATURE

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

MOLECULIN BIOTECH, INC.

Date: April 8, 2022

By: /s/ Jonathan P. Foster

Jonathan P. Foster

EX-99.1

Exhibit 99.1

Moleculin Announces Presentation of Positive Preclinical Annamycin Data at the AACR 2022 Annual Meeting

Annamycin exhibited robust antitumor activity in experimental colorectal cancer liver and lung metastasis models

Results support advancement of preclinical development toward initiating clinical studies in metastatic colorectal cancer patients

HOUSTON, April 8, 2022 /PRNewswire/ -- Moleculin Biotech, Inc., (Nasdaq: MBRX) (“Moleculin” or the “Company”), a clinical stage pharmaceutical company with a broad portfolio of drug candidates targeting highly resistant tumors and viruses, today announced that preclinical data of Annamycin tested in syngeneic models of metastatic colorectal cancer established in lungs or liver was accepted for poster presentation at the American Association for Cancer Research (AACR) Annual Meeting 2022, being held April 8-13, 2022, in New Orleans, Louisiana.

Details of the poster presentation are as follows:

Title: New approach to target metastatic colorectal cancer organotropism with L-Annamycin
Track: Experimental and Molecular Therapeutics
Poster Number: 4048
Session: PO.ET06.05 - New Chemotherapy Agents
Presentation Type: E-Poster presentation
Session Date and Time: Wednesday, April 13, 2022, from 9:00 am – 12:30 p.m. CDT
Section: 27

The objective of this study was to assess the efficacy of Annamycin in experimental colorectal cancer liver and lung metastasis models. The efficacy of Annamycin was tested in syngeneic models of metastatic colorectal cancer established in lungs or liver. For lung metastasis model, CT26-Luc cells were injected intravenously (IV) into Balb/c mice, followed by weekly IV treatment of Annamycin (4 and 6 mg/kg). The liver metastatic model was established using intrasplenic injection protocol. Mice received six weekly IV injections of 4 mg/kg of Annamycin or vehicle. Bioluminescent imaging (BLI), Magnetic Resonance Imaging (MRI) or Computer Tomography (CT) were used to track tumor progression.

Annamycin exhibited robust antitumor activity in both models. In the lung metastasis model, a dose-dependent delay in the tumor progression was visualized by both BLI and CT scan in the Annamycin treated group. The delay correlated with 272% extension of survival in the group receiving 6 mg/kg Annamycin [median survival (MS) 79d for treated vs 29d vehicle, p<0.0001] and 234% for the animals dosed with Annamycin at 4 mg/kg [MS 68d, p=0.0012]. In the liver metastasis model, all vehicle-treated mice showed massive tumors in the liver and peritoneal cavity as monitored by BLI and MRI. In the vehicle group, 13/14 died or were euthanized by 35d (median survival was 34.5d). Yet, no tumors were detected by BLI or MRI in Annamycin treated mice as of 44d and 0/14 mice died (100% survival). This indicates a highly significant (P< 0.0001) extension of survival (ongoing experiment).

“We continue to be encouraged by the growing body of robust preclinical and human clinical data demonstrated by Annamycin. The positive results seen in these preclinical models provide added confidence in the potential follow-on development opportunities we believe Annamycin holds. While metastatic colorectal cancer is not an immediate area of focus for us, this data set continues to provide valuable insight as we advance its clinical development for the treatment of highly resistant tumors," commented Walter Klemp, Chairman and CEO of Moleculin.

In summary, the strategy to develop anticancer agents that imitate metastatic colorectal cancer organotropism appears to be highly promising and is supported by these results. This study demonstrating efficacy of Annamycin in colorectal cancer models provides convincing evidence for further preclinical development aimed at initiation of clinical studies in metastatic colorectal cancer patients.

Annamycin is the Company's next-generation anthracycline that has been shown in animal models to accumulate in the lungs at up to 30-fold the level of doxorubicin, as well as demonstrating the ability to avoid the multidrug resistance mechanisms that typically limit the efficacy of doxorubicin and other currently prescribed anthracyclines. Importantly, Annamycin has also demonstrated a lack of cardiotoxicity in multiple human clinical trials, including ongoing trials for the treatment of relapsed or refractory acute myeloid leukemia (AML) and soft tissue sarcoma (STS) lung metastases, and the Company believes that the use of Annamycin may not face the same usage limitations imposed on doxorubicin, one of the most common currently prescribed anthracyclines. Annamycin is currently in development for the treatment of AML and STS lung metastases and the Company believes it may have the potential to treat a number of additional indications.

Annamycin currently has Fast Track Status and Orphan Drug Designation from the U.S. Food and Drug Administration (FDA) for the treatment of STS lung metastases, in addition to Orphan Drug Designation for the treatment of relapsed or refractory acute myeloid leukemia.

For more information about the Phase 1b/2 study evaluating Annamycin for the treatment of STS lung metastases, please visit clinicaltrials.gov and reference identifier NCT04887298. 

About Moleculin Biotech, Inc.

Moleculin Biotech, Inc. is a clinical stage pharmaceutical company focused on the development of a broad portfolio of drug candidates for the treatment of highly resistant tumors and viruses. The Company's lead program, Annamycin is a next-generation anthracycline designed to avoid multidrug resistance mechanisms with little to no cardiotoxicity. Annamycin is currently in development for the treatment of relapsed or refractory acute myeloid leukemia (AML) and soft tissue sarcoma (STS) lung metastases.

Additionally, the Company is developing WP1066, an Immune/Transcription Modulator capable of inhibiting p-STAT3 and other oncogenic transcription factors while also stimulating a natural immune response, targeting brain tumors, pancreatic and other cancers, and WP1220, an analog to WP1066, for the topical treatment of cutaneous T-cell lymphoma. Moleculin is also engaged in the development of a portfolio of antimetabolites, including WP1122 for the potential treatment of COVID-19 and other viruses, as well as cancer indications including brain tumors, pancreatic and other cancers.

For more information about the Company, please visit www.moleculin.com and connect on Twitter, LinkedIn and Facebook.

Forward-Looking Statements

Some of the statements in this release are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, Section 21E of the Securities Exchange Act of 1934 and the Private Securities Litigation Reform Act of 1995, which involve risks and uncertainties. Forward-looking statements in this press release include, without limitation, whether the results described in the poster will be shown in follow on preclinical and clinical development and whether the Company will be able to develop Annamycin to treat additional indications . Although Moleculin believes that the expectations reflected in such forward-looking statements are reasonable as of the date made, expectations may prove to have been materially different from the results expressed or implied by such forward-looking statements. Moleculin has attempted to identify forward-looking statements by terminology including ''believes,'' ''estimates,'' ''anticipates,'' ''expects,'' ''plans,'' ''projects,'' ''intends,'' ''potential,'' ''may,'' ''could,'' ''might,'' ''will,'' ''should,'' ''approximately'' or other words that convey uncertainty of future events or outcomes to identify these forward-looking statements. These statements are only predictions and involve known and unknown risks, uncertainties, and other factors, including those discussed under Item 1A. "Risk Factors" in our most recently filed Form 10-K filed with the Securities and Exchange Commission ("SEC") and updated from time to time in our Form 10-Q filings and in our other public filings with the SEC. Any forward-looking statements contained in this release speak only as of its date. We undertake no obligation to update any forward-looking statements contained in this release to reflect events or circumstances occurring after its date or to reflect the occurrence of unanticipated events.

Investor Contact:

JTC Team, LLC

Jenene Thomas

(833) 475-8247

MBRX@jtcir.com

XML

Document And Entity Information	Apr. 08, 2022
Document Information [Line Items]
Entity, Registrant Name	MOLECULIN BIOTECH, INC.
Document, Type	8-K
Document, Period End Date	Apr. 08, 2022
Entity, Incorporation, State or Country Code	DE
Entity, File Number	001-37758
Entity, Tax Identification Number	47-4671997
Entity, Address, Address Line One	5300 Memorial Drive
Entity, Address, Address Line Two	Suite 950
Entity, Address, City or Town	Houston
Entity, Address, State or Province	TX
Entity, Address, Postal Zip Code	77007
City Area Code	713
Local Phone Number	300-5160
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity, Emerging Growth Company	false
Title of 12(b) Security	Common Stock, par value $.001 per share
Trading Symbol	MBRX
Security Exchange Name	NASDAQ
Amendment Flag	false
Entity, Central Index Key	0001659617