Form 8-K

8-K — Transcode Therapeutics, Inc.

Accession: 0001104659-26-069810

Filed: 2026-06-03

Period: 2026-06-03

CIK: 0001829635

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — tm2616719d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2616719d1_ex99-1.htm)

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0001829635

2026-06-03

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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): June 3, 2026

TRANSCODE

THERAPEUTICS, INC.

(Exact name of registrant as specified in its

charter)

Delaware

001-40363

81-1065054

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(I.R.S. Employer

Identification No.)

TransCode

Therapeutics, Inc.

Liberty Square, #2382

Boston, Massachusetts

02109

(Address

of principal executive offices, including zip code)

(857)

837-3099

(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:

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))

Securities registered or to be 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 $0.0001 per share

RNAZ

The Nasdaq

Capital Market

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 x

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 8.01 Other Events.

On June 3, 2026, TransCode Therapeutics, Inc.

(“TransCode”) issued a press release announcing further results of its Phase 1a dose escalation clinical trial with TTX-MC138.

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

Note Regarding Forward-Looking Statements

This Current Report on Form 8-K contains

"forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, including, without

limitation, statements concerning the timing, conduct and results of TransCode’s Phase 1a and Phase 2a clinical trials, statements

about microRNAs and their involvement in cancer, and statements concerning the therapeutic potential of TransCode's TTX-MC138 and other

therapeutic candidates. Any forward-looking statements in this Current Report on Form 8-K are based on management's current expectations

of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially and adversely

from those set forth in or implied by such forward-looking statements. These risks and uncertainties include, but are not limited to:

the risks associated with drug discovery and development; the risk that the results of clinical trials will not be consistent with TransCode's

preclinical studies or expectations or with results from previous clinical trials; risks associated with the conduct of clinical trials;

risks associated with TransCode's financial condition and its need to obtain additional funding to support its business activities, including

TransCode's ability to continue as a going concern; risks associated with the timing and outcome of TransCode's planned regulatory submissions;

risks associated with obtaining, maintaining and protecting intellectual property; risks associated with TransCode's ability to enforce

its patents against infringers and defend its patent portfolio against challenges from third parties; risks of competition from other

companies developing products for similar uses; risks associated with TransCode's dependence on third parties; and risks associated with

geopolitical events and pandemics. For a discussion of these and other risks and uncertainties, and other important factors, any of which

could cause TransCode's actual results to differ from those contained in or implied by the forward-looking statements, see the section

entitled "Risk Factors" in TransCode's Annual Report on Form 10-K for the year ended December 31, 2025, as well as

discussions of potential risks, uncertainties and other important factors in any subsequent TransCode filings with the U.S. Securities

and Exchange Commission. Forward-looking statements reflect TransCode’s analysis only on their stated date; TransCode undertakes

no duty to update this information unless required by law.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit No.

Description

99.1

Press Release, dated June 3, 2026

104

Cover Page Interactive Data File (embedded within the Inline XBRL document)

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.

TransCode Therapeutics, Inc.

Date: June 3, 2026

By:

/s/ Philippe Calais

Philippe Calais

Chief Executive Officer

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2616719d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

TransCode Therapeutics

Successfully Completes Phase 1a Clinical Trial, Reports Safety and Stabilization Data for TTX-MC138 in Metastatic Cancer

TransCode reports no dose-limiting

toxicities, durable disease stabilization in metastatic patients; advances to Phase 2 development in ctDNA-positive cancers using next-generation

RNA therapeutics.

BOSTON, June 3,

2026 - TransCode Therapeutics, Inc. (NASDAQ: RNAZ) a clinical stage company pioneering immuno-oncology and RNA for the treatment

of high risk and advanced cancer, today announced further results of the Phase 1a dose escalation clinical trial. The trial met its primary

endpoint of safety, with positive tolerability, combined with disease stabilization in multiple patients, and the absence of dose-limiting

toxicities with its lead therapeutic candidate TTX-MC138. TTX-MC138, an investigational inhibitor of the key metastatic driver, microRNA-10b,

has shown durable disease control. These findings support advancing TTX-MC138 into Phase 2a clinical development to assess efficacy in

patients with circulating tumor DNA (ctDNA) positive colorectal cancer following curative-intent therapy.

TTX-MC138 has been administered to 16

patients who received 86 doses. The median treatment duration was 11.3 weeks, with a range of four to 52.4 weeks, representing 2 to 20

cycles of treatment.

Notably, three patients remain on trial,

and continue to receive TTX-MC138. One patient is at 21 cycles of treatment, another is at 16 cycles, and the third one is at 14 cycles

of treatment. (Table 1)

Table 1: Trial demographics,

met safety primary endpoint

Cohort

Dose

Number

of Patients

DLT’s1

0.8mg/kg

1.6mg/kg

3.2mg/kg2

4.8mg/kg

1 No significant treatment-related

safety events or dose limiting toxicities were observed.

2 Optional backfill 3 with

additional patients.

3 One patient in each of

cohort 2, 3 and 4 currently on study.

TransCode believes these results support its selection of the recommended

Phase 2a dose (RP2D) of 4.8mg/kg.

In addition, the assessment of the trial

patient population underscored the potential for durable disease control in participants with metastatic cancer.

Based on Response Evaluation Criteria in Solid

Tumors (RECIST) standardized criteria to measure tumor response to treatment using imaging to categorize lesions and assess changes in

size over time, 9 out of 14 (64%) of evaluable patients achieved stable disease lasting six months, demonstrating a durable disease activity.

Table 2: Kaplan Meier plot of progression

free survival, overall safety population

“From a clinical perspective,

it is quite encouraging to see how well tolerated this agent has been at the exposures achieved through the Phase 1a dose-escalation

study, without any dose-limiting toxicities. That, combined with the observation of disease stabilization in a population with such advanced

disease supports continued clinical development” noted Keith Flaherty, MD, Director of Clinical Research at the Massachusetts General

Hospital Cancer Center, Professor of Medicine at Harvard Medical School and TransCode’s Advisory Board member.

The pharmacokinetics profile from the analysis

of plasma from patients receiving TTX-MC138 demonstrated evidence of drug bioavailability consistent with earlier preclinical studies.

One patient

diagnosed with metastatic thyroid cancer was noted to have a dramatic decrease in their thyroglobulin levels, a tumor marker

associated with cancer progression. The patient has now had demonstrated stable disease for the last 12 months and is one of the

three patients who remain on study. We believe that the patient’s continued participation in the study, together with the

decline in their thyroglobulin levels, provides further evidence of therapeutic activity from TTX-MC138.

TransCode

Therapeutics, Inc. · 6 Liberty Square #2382 · Boston, MA 02109

A clinical study report is in process.

Several presentations are planned at future scientific congresses.

“As the

safety and tolerability primary objectives of the trial were met, the encouraging rates of disease stabilization provide the

rationale to advance TTX-MC138 clinical development in our recently initiated Phase 2a trial. We continue to believe that TTX-MC138

may offer a promising therapeutic option, if approved, for patients with metastatic disease who have limited treatment

alternatives,” said Daniel Vlock, MD, TransCode Consulting Clinician.

Further

information about the trial is available at www.clinicaltrials.gov,

(NCT Identifier: NCT06260774).

About

TTX-MC138

is a first-in-class therapeutic candidate designed to inhibit microRNA-10b (miR-10b), a microRNA widely believed to be critical to the

emergence and progression of many metastatic cancers. TransCode’s Phase 0 clinical trial produced evidence of delivery of a radiolabeled

version of TTX-MC138 to metastatic lesions.

About

TransCode Therapeutics

TransCode

Therapeutics is an immuno-oncology and targeted cancer therapy company with a focus on treating advanced malignancy. The Company’s

lead therapeutic candidate, TTX-MC138, is focused on treating metastatic tumors that overexpress microRNA-10b, a unique, well-documented

biomarker of metastasis. In addition, TransCode has a portfolio of other first-in-class therapeutic candidates designed to mobilize the

immune system to recognize and destroy cancer cells.

TransCode

Therapeutics, Inc. · 6 Liberty Square #2382 · Boston, MA 02109

Forward-Looking

Statements

This

release contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995,

including, without limitation, statements concerning the timing, conduct and results of TransCode’s Phase 1a and Phase 2a clinical

trials, statements about microRNAs and their involvement in cancer, and statements concerning the therapeutic potential of TransCode’s

TTX-MC138 and other therapeutic candidates. Any forward-looking statements in this press release are based on management’s current

expectations of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially

and adversely from those set forth in or implied by such forward-looking statements. These risks and uncertainties include, but are not

limited to: the risks associated with drug discovery and development; the risk that the results of clinical trials will not be consistent

with TransCode’s preclinical studies or expectations or with results from previous clinical trials; risks associated with the conduct

of clinical trials; risks associated with TransCode’s financial condition and its need to obtain additional funding to support

its business activities, including TransCode’s ability to continue as a going concern; risks associated with the timing and outcome

of TransCode’s planned regulatory submissions; risks associated with obtaining, maintaining and protecting intellectual property;

risks associated with TransCode’s ability to enforce its patents against infringers and defend its patent portfolio against challenges

from third parties; risks of competition from other companies developing products for similar uses; risks associated with TransCode’s

dependence on third parties; and risks associated with geopolitical events and pandemics. For a discussion of these and other risks and

uncertainties, and other important factors, any of which could cause TransCode’s actual results to differ from those contained

in or implied by the forward-looking statements, see the section entitled “Risk Factors” in TransCode’s Annual Report

on Form 10-K for the year ended December 31, 2025, as well as discussions of potential risks, uncertainties and other important

factors in any subsequent TransCode filings with the U.S. Securities and Exchange Commission. All information in this press release is

as of the date of this release; TransCode undertakes no duty to update this information unless required by law.

For

more information and partnering opportunities, please contact:

TransCode Therapeutics, Inc.

Tania Montgomery, VP of Business Development

tania.montgomery@transcodetherapeutics.com

TransCode

Therapeutics, Inc. · 6 Liberty Square #2382 · Boston, MA 02109

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