Moleculin Biotech, Inc. reports developments as a clinical-stage pharmaceutical company advancing drug candidates for hard-to-treat tumors and viruses. Its lead program is Annamycin, also known as naxtarubicin, a next-generation anthracycline designed to avoid cardiotoxicity and multidrug resistance, with development focused on relapsed or refractory acute myeloid leukemia and soft tissue sarcoma lung metastases.
Recurring news covers Annamycin clinical and preclinical data, the MIRACLE study of Annamycin in combination with cytarabine, oncology conference presentations, intellectual-property protection for liposomal Annamycin, and corporate financial updates. Additional pipeline coverage includes WP1066, an immune/transcription modulator targeting p-STAT3 and other oncogenic transcription factors, and WP1122, an antimetabolite program for pathogenic viruses and cancer indications.
Moleculin Biotech (MBRX) closed enrollment in Part A of its Phase 2/3 MIRACLE leukemia trial with 89 subjects enrolled. One additional subject is in screening. The randomized, double-blind trial compares two doses of Annamycin plus cytarabine with cytarabine plus placebo in adults with relapsed or refractory acute myeloid leukemia.
A comprehensive Part A efficacy and safety readout is planned for the first quarter of 2027 to inform dose selection for Part B. The company estimates the final population will be approximately evenly split between subjects previously treated with intensive 7+3 chemotherapy and venetoclax-based regimens. It expects an approximately 50/50 split between “fit” and “unfit” subjects, versus roughly 70/30 among the first 45, and cautions that the greater “unfit” share may make responses harder to achieve. Blinded trial data continue to show no cardiotoxicity; results by treatment arm remain pending.
Moleculin Biotech (MBRX) published a peer-reviewed cardiac safety analysis of Annamycin involving 90 patients across five clinical trials.
The trials included patients with acute myeloid leukemia or metastatic soft tissue sarcoma; 78 had paired heart ultrasounds. Mean left ventricular ejection fraction, a measure of heart pumping function, was 60.6% at baseline and 60.0% after treatment, with no statistically significant change (p=0.84). An independent Cleveland Clinic cardio-oncology evaluation found no clinical or subclinical evidence of treatment-related heart toxicity, including at cumulative exposures above conventional anthracycline lifetime limits. Median cumulative Annamycin dose was 660 mg/m². Annamycin remains under evaluation for relapsed or refractory acute myeloid leukemia.
Moleculin Biotech (MBRX) announced preclinical pancreatic cancer findings on September 25, 2026, linking Annamycin's antitumor activity partly to CD8+ T cells.
In pancreatic cancer models, these immune cells appeared to contribute to Annamycin's effects alongside its direct cancer-cell killing activity. The findings suggest the drug could make tumors more susceptible to immune attack, but they do not establish an effect in patients. The data are being presented at the AACR Conference on Pancreatic Cancer, held September 25–28 in San Diego. Moleculin sees a possible basis for studying combination treatments.
Annamycin is not currently in clinical development for pancreatic cancer. Moleculin's lead program remains the ongoing MIRACLE trial of AnnAraC in relapsed or refractory acute myeloid leukemia. The pancreatic cancer findings are not part of that trial, and preclinical results may not predict outcomes in humans.
Moleculin Biotech (MBRX) received Mexican Patent No. 436849 covering its proprietary lung-targeted liposomal Annamycin technology, extending protection in Mexico until November 23, 2040.
The patent reinforces a growing global intellectual property estate around Annamycin, a novel anthracycline being evaluated in the pivotal MIRACLE Phase 2/3 trial for relapsed or refractory acute myeloid leukemia (AML). The patented liposomal formulation is designed to enhance delivery of Annamycin to pulmonary tumors and metastatic disease, supporting potential use beyond hematologic cancers. Management describes strong international patent coverage as central to protecting the long-term commercial opportunity of the Annamycin platform.
Moleculin Biotech (MBRX) will present new preclinical data on its lead cancer drug candidate Annamycin (naxtarubicin) at three scientific meetings in September 2026, including the AACR Conference on Pancreatic Cancer.
Talks in Wroclaw, Poland, at the XIII Congress of the Polish Medical Diaspora and an invited lecture at the Hirszfeld Institute will address Annamycin’s lipophilic tissue distribution (“organotropism”) and its topoisomerase II–targeting mechanism. A separate AACR presentation in San Diego will cover antitumor activity in pancreatic cancer and potential CD8+ T cell–mediated effects; its abstract remains embargoed until September 25, 2026, at 1:00 p.m. ET. These efforts run alongside Moleculin’s MIRACLE Phase 2/3 AnnAraC trial in relapsed or refractory AML, which the company states is its primary development focus.
Moleculin Biotech (MBRX) announced that its pre-recorded presentation from the H.C. Wainwright 28th Annual Global Investment Conference is now available for on-demand viewing starting September 11, 2026, at 7:00 a.m. ET.
The webcast, presented by Chairman and CEO Walter Klemp, covers an overview of the company plus recent corporate and clinical developments, and can be accessed via the Events page in the Investors section of moleculin.com. Management will also attend the conference in New York from September 14-16, 2026, for one-on-one meetings with registered investors. Moleculin describes itself as a Phase 3 clinical stage pharmaceutical company focused on hard-to-treat tumors and viruses, led by its Annamycin (naxtarubicin) program.
Moleculin Biotech (Nasdaq: MBRX) announced that CEO and Chairman Walter Klemp participated in the Virtual Investor “Why Now” on-demand conference, where he highlighted the Company’s clinical progress and long-term opportunity.
The presentation discussed encouraging interim results from the pivotal Phase 2/3 MIRACLE trial (MB-108) of Annamycin (naxtarubicin) for relapsed or refractory acute myeloid leukemia (AML), its differentiated clinical profile, continued enrollment, expanding commercial opportunity, and an upcoming 90-patient interim analysis viewed by the Company as a key potential value catalyst toward registration. The webcast is now available for on-demand viewing. Moleculin also outlined its broader pipeline, including Annamycin for soft tissue sarcoma lung metastases, the immune/transcription modulator WP1066 for various cancers, and antimetabolites such as WP1122 for pathogenic viruses and certain cancers.
Moleculin Biotech (Nasdaq: MBRX) reported second quarter 2026 results and progress in its pivotal Phase 2/3 MIRACLE trial of Annamycin in relapsed/refractory AML. According to Moleculin, interim unblinded data from the first 45 Part A patients showed complete remission (CR) rates of 43% and 36% in the two Annamycin plus cytarabine arms versus 12% in the cytarabine control arm, with composite CR (CRc) of 50% and 57% versus 29% for control, and no evidence of cardiotoxicity.
Enrollment is on track to complete the 90-patient Part A in September 2026, with an unblinded efficacy readout expected between December 2026 and February 2027 and Part B initiation planned for the first half of 2027. Research and development expenses rose to $5.5 million from $3.6 million year over year, while general and administrative expenses were stable at $2.1 million. Moleculin reported a Q2 2026 net loss of $7.6 million and ended June 30, 2026 with $7.3 million in cash and equivalents; together with $9.3 million raised after quarter-end, this is expected to fund operations into the first quarter of 2027.
Moleculin (Nasdaq: MBRX) priced a best-efforts public offering of approximately $9.3 million, consisting of 12,376,667 shares of common stock (or pre-funded warrants in lieu) and common warrants to purchase up to 37,130,001 shares at a combined public offering price of $0.75 per share and associated warrants.
The common warrants are immediately exercisable at $0.75 per share and expire five years after initial exercise. Closing is expected on or about August 3, 2026, subject to customary conditions. According to Moleculin, net proceeds will be used to advance its drug candidate Annamycin through clinical development and for working capital. The securities are offered under an effective Form S-1 registration statement.
Moleculin (Nasdaq: MBRX) reported updated preliminary blinded data from Part A of its pivotal Phase 2/3 MIRACLE trial of Annamycin plus cytarabine (AnnAraC) in relapsed/refractory AML. Among 62 evaluable subjects, blinded complete remission (CR) was 24% and composite CR (CRc) was 37% after a single treatment cycle.
Of these, 30 patients had failed prior first-line venetoclax-based therapy, with blinded CR and CRc of 23% and 37%, respectively. According to Moleculin, this compares with published salvage CRc of about 13% and median survival of 2.4 months after venetoclax failure, though this is not a controlled comparison. Enrollment has reached 74 of 90 subjects, with final Part A treatment expected in September 2026 and comprehensive unblinded Part A results anticipated between December 2026 and February 2027. Across three blinded looks, CRc has remained near 37–40%, and the company reports no evidence of cardiotoxicity to date.