Dr. Fahar Merchant reports

MEDICENNA THERAPEUTICS ANNOUNCES KEY PROGRAM UPDATES AND 2026 OUTLOOK

Medicenna Therapeutics Corp. has provided management's outlook for 2026, highlighting significant advancements in its key programs.

"As we head into 2026, we are building on the foundational milestones achieved in 2025 and are poised for a potentially transformative year of growth as we aim to establish Medicenna as a pre-eminent leader in the development of best and first-in-class superkine-based therapeutics," said Dr. Fahar Merchant, PhD, president and chief executive officer of Medicenna. "We are encouraged by the updated and expanding clinical data set for MDNA11, particularly in the 2L/3L setting and after checkpoint failure, which has unquestionably positioned it as a best-in-class IL-2 superagonist. With the planned addition of MDNA113, a first-in-class IL-13 directed and conditionally activated bifunctional anti-PD1-IL-2 superkine, into our clinical armamentarium, we are well positioned to further leverage the promise of our IL-2 platform, blockbuster anti-PD1 therapy and our T-Mask platform to advance highly precise and safer immunotherapies to treat patients with cold tumours that do not respond to currently available treatment options. These accomplishments reflect our team's hard work and dedication, and we are pleased to share them with you."

MDNA11: promising results in the continuing phase 1/2 Ability-1 study

To date, the Ability-1 trial has enrolled over 110 safety evaluable patients (of which 102 are efficacy evaluable at this time), with 29 different types of cancer in monotherapy and combination arms at doses ranging from three to 120 grams per kilogram without any signs of dose limiting toxicities in patients with up to 15 lines of prior therapy and established the biologically effective dose range at 60 to 120 g/kg.

Updated MDNA11 data demonstrate the following:

• Among monotherapy expansion cohorts (n equals 21), ORR reached 50 per cent in patients treated with MDNA11 as a 2L/3L treatment and 42 per cent when MDNA11 was the next treatment line post-ICI failure, demonstrating its best-in-class potential in earlier settings post-ICI treatment failure;
• Among all efficacy-evaluable monotherapy patients enrolled to date (n equals 55) comprising 18 different cancers, ORR reached 19 per cent in patients treated with MDNA11 as a 2L/3L treatment and 24 per cent when MDNA11 was the next treatment line post-ICI failure;
• Similar trends were observed in the MDNA11 plus pembrolizumab combination cohorts;
• MDNA11 monotherapy response data in expansion cohorts (N equals 21):
  • 37.5-per-cent ORR in cutaneous melanoma (two-degree ICI resistance) (N equals eight);
  • 25-per-cent ORR in MSI-H cancers (N equals eight);
• MDNA11 plus Pembrolizumab response data in combination expansion cohorts (N equals 21):
  • 50-per-cent ORR in MSS endometrial cancer (two-degree ICI resistance) (N equals four);
  • 43-per-cent ORR in MSS TMB-H cancers (N equals seven);
  • 25-per-cent ORR in MSI-H cancers (N equals four);
  • 17-per-cent ORR in cutaneous melanoma (one-degree ICI resistance) (N equals six).

NEO-CYT trial: expanding MDNA11 into earlier lines of therapy

In collaboration with the Fondazione Melanoma Onlus, the NEO-CYT trial is a randomized, multicentre neoadjuvant study in high-risk, resectable Stage 3 melanoma, evaluating MDNA11 in combination with nivolumab, with or without ipilimumab. Medicenna anticipates commencement of the NEO-CYT study in first half 2026 with interim data readouts in second half 2026.

MDNA113: preliminary non-human primate data are promising

MDNA113, Medicenna's first-in-class, tumour-anchored and conditionally activated PD-1 by IL-2 bifunctional superkine, is advancing through preclinical development. Medicenna is planning to commence first-in-human trial in second half of 2026.

Non-human primate studies are currently under way, with updated data reported today demonstrating its potential to dramatically widen the therapeutic index:

• MDNA113 was well tolerated in non-human primates with no untoward clinical findings at the highest tested doses (30 milligrams per kilogram), supporting dosing in humans at or exceeding doses currently administered with standard-of-care anti-PD-1 therapies;
• Lack of C-reactive protein increase following MDNA113 dosage;
• Limited peripheral T-cell expansion with MDNA113 despite a 30-fold increase in dosage compared with a non-masked version of MDNA113.

Based on the preliminary non-human primate and previously reported preclinical data, management believes MDNA113 has greater potential compared with other PD-1 by IL-2 programs in development, which aim to outperform megablockbuster commercial anti-PD-1 therapies.

Bizaxofusp: advancing partnering efforts

The company is committed to advance bizaxofusp toward the next stage of development through active partnering discussions, driven by the differentiated clinical data from a phase 2b study and the significant unmet need in non-resectable recurrent GBM. It will present multiple external and internal data sets from metaanalysis and bioinformatic platforms including ex vivo studies at the seventh annual GBM summit to be held in Boston from Feb. 17 to Feb. 19, 2026. These data together with its clinical data provide a compelling rationale for further development of bizaxofusp for central nervous system diseases.

In 2026, Medicenna will focus on three strategic priorities to drive long-term growth:

1. Maximize the monotherapy and combination potential of MDNA11 in well-defined earlier-line and neoadjuvant settings to maximize market expansion opportunities;
2. Advance its next-generation pipeline comprising MDNA113 as a potential first- and best-in-class targeted, masked bifunctional anti-PD1-IL-2 superkine, and demonstrate the full value and multiple opportunities of its T-Mask and BiSKIT platforms;
3. Advance bizaxofusp through partnership or collaboration for recurrent GBM and other brain cancers.

Key milestones expected for 2026:

• Complete patient enrolment in Ability-1 study in MDNA11 monotherapy and combination arms across prioritized indications (cutaneous melanoma, endometrial cancer, MSI-H/dMMR and MSS/TMB-H cancers) including any new expansion cohorts (for example, CRC and NSCLC) with a focus on 2L/3L in postanti-PD1 settings;
• Report updated clinical data from MDNA11 monotherapy and combination expansion cohorts including 2L/3L and last-line anti-PD1-treated patients enrolled within the Ability-1 study;
• Share interim clinical data from the phase 1/2 study of MDNA11 in neoadjuvant melanoma trial (NEO-CYT) throughout 2026;
• Secure Food and Drug Administration guidance on first potential registrational trial of MDNA11 in at least one advanced cancer indication in 2L/3L setting post-ICI therapy, including dose selection for project optimus;
• File an investigational new drug application for MDNA113 in second half 2026 and initiate a phase 1/2a trial by fourth quarter 2026;
• Strengthen the balance sheet through partnership and/or financing by mid-2026 in preparation for registrational trial for MDNA11 and commence FIH trial for MDNA113;
• Present new preclinical and clinical data on bizaxofusp and IL-4Ralpha biology in recurrent GBM in first quarter 2026;
• Advance and close a strategic collaboration or partnership for bizaxofusp in 2026;
• Strengthen management team and board of directors throughout 2026.

About Medicenna Therapeutics Corp.

Medicenna is a clinical-stage immunotherapy company focused on developing novel, highly selective versions of IL-2, IL-4 and IL-13 superkines and first-in-class empowered superkines. Medicenna's long-acting IL-2 superkine, MDNA11, is a next-generation IL-2 with superior affinity toward CD122 (IL-2 receptor beta) and no CD25 (IL-2 receptor alpha) binding, thereby preferentially stimulating cancer-killing effector T-cells and NK-cells. Medicenna's first-in-class targeted PD-1 by IL-2 bispecific, MDNA113, is in development for solid tumours, and was designed using the company's proprietary BiSKITs (bifunctional superkine immunotherapies) and T-Mask (targeted metalloprotease activated superkine) platforms. Medicenna's IL-4 empowered superkine, bizaxofusp (formerly MDNA55), has been studied in five clinical trials enrolling over 130 patients, including a phase 2b trial for recurrent GBM, the most common and uniformly fatal form of brain cancer. Bizaxofusp has obtained fast-track and orphan drug status from the FDA and FDA/European Medicines Agency, respectively.

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