Immuneering Advances Towards Dosing First Patient in Phase 3 Atebimetinib Trial for First-Line Metastatic Pancreatic Cancer Patients, Securing Alignment with FDA and EMA

Rhea-AI Summary

Immuneering (Nasdaq: IMRX) said it completed End-of-Phase 2 interactions with the FDA and received scientific advice from the EMA, achieving alignment on its planned global Phase 3 registrational trial MAPKeeper 301 for atebimetinib (320 mg QD) + mGnP in first-line metastatic pancreatic ductal adenocarcinoma.

The company plans to enroll ~510 patients, use overall survival as the primary endpoint, expects to dose the first patient in mid-2026, and plans to report topline results in mid-2028. Management reiterated that current cash and equivalents are expected to fund operations into 2029. An overall survival update from the Phase 2a trial is planned in the coming weeks.

Positive

• EOP2 alignment achieved with FDA and EMA
• Phase 3 expanded to ~510 patients
• Primary endpoint is overall survival
• First patient dosing planned for mid-2026
• Topline results expected in mid-2028
• Cash runway expected to fund operations into 2029

Negative

• None.

Key Figures

Phase 3 dose 320 mg QD Atebimetinib dose in planned Phase 3 MAPKeeper 301 trial

Planned enrollment 510 patients Total planned enrollment for global Phase 3 trial

First patient timing Mid-2026 Expected timing to dose first patient in Phase 3

Topline data timing Mid-2028 Company’s expectation for Phase 3 topline results

Phase 2a patients 34 patients First-line pancreatic cancer patients in atebimetinib + mGnP Phase 2a

Cash runway Into 2029 Management’s stated cash and cash equivalents runway

Share price vs. low 421.82% above Price vs. 52-week low of $1.10 before this news

Share price vs. high -43.06% below Price vs. 52-week high of $10.08 before this news

Market Reality Check

$5.65 Last Close

Volume Volume 762,631 is slightly below 20-day average of 817,523 (relative volume 0.93x). normal

Technical Shares at $5.74 are trading above the 200-day MA at $4.09, well above the $1.10 52-week low but below the $10.08 high.

Peers on Argus

Peer biotech names show mixed moves: some modestly higher (e.g., RCKT +0.59%, TECX +2.47%) and others lower (ASMB, FULC, LRMR), suggesting IMRX trading reflects stock-specific factors rather than a clear sector trend.

Historical Context

Date	Event	Sentiment	Move	Catalyst
Dec 16	Index inclusion	Positive	-0.7%	Addition to Nasdaq Biotechnology Index effective December 22, 2025.
Nov 25	Conference appearance	Neutral	-0.7%	Piper Sandler healthcare conference presentation and investor meetings.
Nov 12	Earnings & clinical	Positive	-1.8%	Strong Phase 2a data plus major financings and extended cash runway.
Nov 04	Earnings preview	Neutral	+0.5%	Scheduling of Q3 earnings call and new clinical case studies.
Sep 26	Clinical data call	Positive	-16.5%	Discussion of Phase 2a overall survival and safety data in pancreatic cancer.

Pattern Detected

Recent news, including positive clinical and index/financing milestones, often saw negative or muted 24-hour reactions, indicating a pattern of sell-the-news or skepticism around positive updates.

Recent Company History

Over the last six months, Immuneering reported multiple milestones tied to atebimetinib in first-line pancreatic cancer, including Phase 2a survival data and conference presentations, alongside substantial financings and index inclusion. Despite generally constructive clinical and corporate news, 24-hour price reactions were frequently negative (e.g., -16.46% on a Phase 2a update, -23.21% on positive survival data), suggesting investors have reacted cautiously even to favorable developments. Today’s Phase 3 alignment and timeline build directly on those Phase 2a results and prior pivotal-planning disclosures.

Regulatory & Risk Context

Active S-3 Shelf Registration 2025-08-13

$300,000,000 registered capacity

An effective Form S-3 filed on 2025-08-13 registers up to $300,000,000 of securities, including an equity distribution agreement covering up to $100,000,000 of Class A stock via Piper Sandler & Co. This provides flexibility to raise capital, and there have been 2 recent prospectus supplements (Form 424B5), indicating some usage of the shelf program.

Market Pulse Summary

This announcement details regulatory alignment with both FDA and EMA and a clear path to a global Phase 3 trial in first-line metastatic pancreatic cancer, targeting about 510 patients with overall survival as the primary endpoint and topline data expected around mid-2028. It builds directly on prior Phase 2a survival data and existing plans to start dosing in mid-2026. Investors may watch future overall survival updates, enrollment progress, and any use of the $300,000,000 shelf as the program advances.

Key Terms

phase 3 medical

"global Phase 3 registrational trial, MAPKeeper 301, in mid-2026"

Phase 3 is the late-stage clinical testing step for a new drug or medical treatment, where the product is given to large groups of patients to confirm effectiveness, monitor side effects, and compare it to standard care. Successful Phase 3 results are often the final scientific hurdle before regulators decide on approval and market launch—like passing a final exam before graduation—and can sharply change a company's valuation and future revenue prospects.

overall survival medical

"key primary endpoint of overall survival, and we are confident"

Overall survival is the average or median length of time patients remain alive after starting a treatment or entering a clinical study, measured regardless of cause of death. Investors care because it is a clear, hard measure of a therapy’s real-world benefit — like timing how long a new battery actually runs — and strong improvements in overall survival can drive regulatory approval, market adoption and revenue potential.

progression-free survival medical

"secondary endpoints include progression-free survival, overall response rate"

Progression-free survival is the length of time during and after a treatment that a patient's disease does not get worse, measured from the start of treatment until the disease shows measurable signs of progression or the patient dies. Investors care because longer progression-free survival in clinical trials often signals that a drug is effective, improving chances of regulatory approval, market adoption, and revenue potential—think of it as a stopwatch showing how long a therapy can keep the illness at bay.

overall response rate medical

"secondary endpoints include progression-free survival, overall response rate"

Overall response rate is the percentage of patients in a clinical study whose measurable disease shrinks or disappears after receiving a treatment. Investors watch it like a product’s “hit rate” because higher response rates can signal a drug’s effectiveness, boost chances of regulatory approval and market demand, and affect a company’s future revenue prospects, similar to how a higher batting average suggests a more reliable player.

disease control rate medical

"overall response rate, disease control rate, and quality of life"

The disease control rate is the share of patients in a clinical trial whose cancer or condition either shrinks or stops getting worse for a specified period after treatment. Think of it like the percentage of people for whom a treatment hits pause or nudges back the problem rather than letting it progress; higher rates suggest the therapy can meaningfully limit disease, which matters to investors assessing a drug’s potential efficacy and commercial value.

quality of life medical

"disease control rate, and quality of life measurements."

Quality of life is a measure of how a medical condition and its treatment affect a person’s daily well‑being, functioning, comfort, and ability to do routine activities — essentially a patient’s own “product review” of how life feels. Investors watch it because improvements in quality of life can influence regulatory approvals, medical guidelines, prescription uptake, insurance coverage, and a treatment’s market value, much like customer satisfaction drives sales for a consumer product.

metastatic medical

"first-line metastatic pancreatic ductal adenocarcinoma. The primary endpoint"

Metastatic describes cancer that has spread from its original spot to other organs or tissues, like weeds moving from one garden bed into several others. For investors, metastatic disease matters because it often requires more complex, long-term treatments, larger clinical trials, and can drive demand for specialized drugs and diagnostics—factors that affect a drug’s development costs, regulatory risk, market size, and potential revenue.

randomized phase III medical

"see this combination move forward to a randomized phase III evaluation."

A randomized phase III is a late-stage clinical study in which large groups of patients are randomly assigned to receive either the new treatment or a comparison (such as the current standard care or a placebo) to measure whether the treatment is safe and works better in real-world settings. Think of it as a final, large-scale field test: positive results are a key step toward regulatory approval and wide sales, while negative results can stop a drug’s commercial path and affect investor value.

AI-generated analysis. Not financial advice.

– End-of-Phase 2 interactions with FDA complete; scientific advice received from EMA –

– Company expects to dose first patient in global Phase 3 registrational trial, MAPKeeper 301, in mid-2026 –

– Overall survival update for Phase 2a trial of atebimetinib + mGnP in first-line pancreatic cancer patients planned in coming weeks –

NEW YORK, Dec. 17, 2025 (GLOBE NEWSWIRE) -- Immuneering Corporation (Nasdaq: IMRX), a late-stage clinical oncology company focused on keeping cancer patients alive and helping them thrive, today announced that it is on track to dose the first patient in its planned global Phase 3 registrational trial in first line pancreatic cancer patients in mid-2026, evaluating atebimetinib (320 mg QD) in combination with modified gemcitabine and nab-paclitaxel (mGnP), compared with gemcitabine and nab-paclitaxel (GnP) alone.

Notably, the company completed its End-of-Phase 2 (EOP2) interactions with the U.S. Food and Drug Administration (FDA) and received scientific advice from the European Medicines Agency (EMA). Immuneering achieved alignment with both agencies on the key elements of the company’s proposed Phase 3 trial.

“We are very pleased with our interactions with both the FDA and EMA, which we believe speaks to the compelling data we have generated to date in first-line pancreatic cancer, as well as the strength and simplicity of our proposed Phase 3 trial for atebimetinib,” said Ben Zeskind, Ph.D., Co-Founder and Chief Executive Officer of Immuneering. “Importantly, the regulators’ feedback supports our trial design and key primary endpoint of overall survival, and we are confident that our team is well-positioned to begin dosing patients in this global registrational trial in mid-2026. We are also thrilled to expand the planned trial to 510 patients, which gives more first-line pancreatic cancer patients the opportunity to participate, and further increases statistical robustness. In addition, we are excited to provide an update on overall survival in the Phase 2a trial in the coming weeks.”

MAPKeeper 301 is designed as a global Phase 3 trial that will evaluate atebimetinib (320 mg QD) in combination with mGnP, compared to standard of care GnP alone, in first-line metastatic pancreatic ductal adenocarcinoma. The primary endpoint of the trial is overall survival, and secondary endpoints include progression-free survival, overall response rate, disease control rate, and quality of life measurements. Immuneering plans to enroll a total of approximately 510 patients in the Phase 3 trial.

The company expects to dose the first patient in mid-2026 and share topline results from the trial in mid-2028. Immuneering also reiterated management’s belief that the company’s current cash and cash equivalents, based on current operating plans, are sufficient to fund operations into 2029.

“The constructive guidance from both agencies validates our scientific approach and our understanding of the unmet need in first-line metastatic pancreatic cancer,” said Igor Matushansky, M.D., Ph.D., Chief Medical Officer of Immuneering. “We look forward to advancing atebimetinib into Phase 3 and working with investigators worldwide to bring this potentially transformative therapy to patients as expeditiously as possible.”

“New therapies for pancreatic cancer are urgently needed,” said Eileen M. O’Reilly, MD, FASCO, Winthrop Rockefeller Endowed Chair in Medical Oncology at Memorial Sloan Kettering Cancer Center. “The phase IIa data of atebimetinib and chemotherapy shows a promising signal. I am excited to see this combination move forward to a randomized phase III evaluation.”

About Immuneering Corporation

Immuneering is a late-stage clinical oncology company focused on keeping cancer patients alive and helping them thrive. The Company is developing an entirely new category of cancer medicines, Deep Cyclic Inhibitors. Immuneering’s lead product candidate, atebimetinib, is an oral, once-daily Deep Cyclic Inhibitor of MEK, designed to improve durability and tolerability across many cancer indications, including MAPK pathway-driven tumors such as pancreatic cancer. Atebimetinib is currently planned to be evaluated in a Phase 3 trial in first-line pancreatic cancer, which is expected to begin dosing in mid-2026. The Company’s development pipeline also includes early-stage programs. For more information, please visit www.immuneering.com.

Forward-Looking Statements

This press release contains forward-looking statements, including within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including, without limitation, statements regarding: our plans to develop, manufacture and commercialize our product candidates; the treatment potential of atebimetinib, alone or in combination with other agents to treat cancer, including modified Gemcitabine/nab-paclitaxel (mGnP) in first-line pancreatic cancer; the timing of future data updates; the regulatory feedback supporting our Phase 3 trial design and initiation of the trial, including the key primary endpoint of overall survival and validating our scientific approach, expectations regarding our cash runway; the timing of dosing the first patient and topline readout in our planned phase 3 trial; and our belief that our regulatory interactions speak to the compelling data we have generated to date in first-line pancreatic cancer, as well as the strength and simplicity of our proposed Phase 3 trial for atebimetinib.

These forward-looking statements are based on management’s current expectations. These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including, but not limited to, the following: the risks inherent in oncology drug research and development, including target discovery, target validation, lead compound identification, and lead compound optimization; we have incurred significant losses, are not currently profitable and may never become profitable; our projected cash runway; our need for additional funding; our unproven approach to therapeutic intervention; our ability to address regulatory questions and the uncertainties relating to regulatory filings, reviews and approvals; the lengthy, expensive, and uncertain process of clinical drug development, including potential delays in or failure to obtain regulatory approvals; our reliance on third parties and collaborators to conduct our clinical trials, manufacture our product candidates, and develop and commercialize our product candidates, if approved; failure to compete successfully against other drug companies; protection of our proprietary technology and the confidentiality of our trade secrets; potential lawsuits for, or claims of, infringement of third-party intellectual property or challenges to the ownership of our intellectual property; our patents being found invalid or unenforceable; costs and resources of operating as a public company; and unfavorable or no analyst research or reports.

These and other important factors discussed under the caption “Risk Factors” in our Quarterly Report on Form 10-Q for the period ended September 30, 2025, and our other reports filed with the U.S. Securities and Exchange Commission, could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any such forward-looking statements represent management's estimates as of the date of this press release. While we may elect to update such forward-looking statements at some point in the future, except as required by law, we disclaim any obligation to do so, even if subsequent events cause our views to change. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release.

Media Contact:
Carson Creehan
202-878-8330
Carson.creehan@padillaco.com

Investor Contact:
Laurence Watts
619-916-7620
laurence@newstreetir.com

FAQ

When does Immuneering expect to dose the first patient in the MAPKeeper 301 Phase 3 trial (IMRX)?

Immuneering expects to dose the first patient in mid-2026.

How many patients will the MAPKeeper 301 Phase 3 trial (IMRX) enroll?

The company plans to enroll approximately 510 patients.

What is the primary endpoint of Immuneering's Phase 3 trial for atebimetinib (IMRX)?

The primary endpoint is overall survival in first-line metastatic pancreatic ductal adenocarcinoma.

When does Immuneering expect to report topline results from MAPKeeper 301 (IMRX)?

Topline results are expected in mid-2028.

Did Immuneering receive regulatory alignment for its Phase 3 design (IMRX)?

Yes; Immuneering completed End-of-Phase 2 interactions with the FDA and received scientific advice from the EMA with alignment on key trial elements.

How long is Immuneering's cash runway based on current operating plans (IMRX)?

Management reiterated that current cash and cash equivalents are expected to fund operations into 2029.