Subcutaneous Blinatumomab Shows Early Promise in MPAL in First-of-a-Kind Study

Subcutaneous (SC) administration of the CD-19 targeting bispecific, blinatumomab (Blincyto), was well tolerated and yielded a complete response (CR) in a patient with CD19-positive mixed phenotype acute leukemia (MPAL), highlighting the potential of this treatment approach for patients with this rare hematologic malignancy, according to Ashkan Emadi, MD, PhD.¹

Data from an ongoing phase 2 trial (NCT07222579) showed that the first patient in the study with MPAL achieved a CR with complete hematologic recovery after receiving 1 cycle of SC blinatumomab, which started on January 16. This patient experienced transfusion independence and had Philadelphia chromosome (Ph)–negative disease. Emadi also mentioned that this patient was in the hospital for 7 days and at home for the remainder of their first 26-day treatment cycle.^1,2

Regarding the trial itself, Emadi said the trial is the first-of-its-kind for MPAL. The study will include up to 75 patients and is open for enrollment.¹

“If you asked me on January 16 [if I would have anticipated] I see this level of efficacy [after 1 cycle of treatment], I would not [have been able to believe it],” said Emadi in an interview with OncLive^®. “This is the ultimate dream of leukemia doctors.”

In the interview, Emadi discussed the design of the trial and how it covers all bases of MPAL, in addition to why early data that have been reported are particularly promising.

Emadi is the chair of the Department of Medical Oncology, the Alexander Bland Osborn Endowed Chair and Distinguished Professor of Medical Oncology at the West Virginia University (WVU) School of Medicine; as well as the physician-in-chief for Medical Oncology and the associate director for Clinical Research at WVU Cancer Institute, both in Morgantown.

OncLive: How was this trial designed to evaluate blinatumomab specifically in patients with MPAL?

Emadi: I might be biased since I designed the protocol, but the design of the protocol is novel. When I was writing this protocol, I kept in mind my knowledge as a leukemia doctor and the rarity, unmet needs, and the incident of [MAPL]. I wanted to have a protocol that as an umbrella, covering all of patients with MPAL.

Cohort C and B are easy [to explain]. Cohort C includes patients with relapsed or refractory with MPAL who have already received chemotherapy, so they most likely have no other options. Cohort B is for patients who achieved a [first or second] CR but had [detectable] minimal residual disease [MRD]. This is a smaller [group of] patients, [and although] they have already achieved a CR, maybe [blinatumomab] can eliminate the residual disease. If these patients are younger or medically fit, they can go to allogeneic stem cell transplantation. [This cohort] was only 10 patients. Cohort A enrolled [newly diagnosed] older patients who were 75 years of age or older, or patients who cannot tolerate cytotoxic chemotherapy.

When all 75 patients are enrolled, the results will be based on the totality of the data. [Thus, we] will know about the efficacy and safety of SC blinatumomab in adult patients who are older, medically unfit, relapsed/refractory, and MRD-positive. [The design of the trial] gives you a whole tour de force—360 degrees of understanding for the efficacy of the drug, the durability of that efficacy, and the [safety] profile of the drug. Hopefully, [if] the drug comes to the market for this indication, there will be a vast [pool of data]. When I designed the protocol, I had all of these things in mind that, 5 years from now, if I'm a medical oncologist and I want to give this drug and I look at the outcomes of this study, everything that I need to know will be in that final analysis of this study.

What are the most surprising efficacy and safety data to emerge thus far from the trial evaluating blinatumomab in MPAL?

Except for grade 1 cytokine release syndrome, this patient, who was a 77-year-old, [was] walking 2 miles a day. [SC blinatumomab] was extremely well tolerated [in this patient]. She did not have any neutropenic fever, and her counts recovered very nicely by day 26. The tolerability of [SC blinatumomab] was amazing, particularly in a patient who was an older adult.

This patient cleared their [bone marrow] blasts, had no increased blasts in the blood, and Ph-negative disease. They are truly transfusion dependent. [Treatments] used to have patients receiving a lot of cytotoxic therapy, being in the hospital [often], and being on a lot of intravenous antibiotics. This patient was only in the hospital for 7 days, and that was the protocol mandate per the FDA’s recommendation; then for the rest [of treatment cycle, they] were out of the hospital. With the [efficacy], I honestly didn't expect this depth of remission in this patient.

How could results from this trial influence clinical practice for MPAL? What are the next steps for investigating SC blinatumomab in this population?

[We have only treated] 1 patient,, which is the reason that this study is open. I hope that this [data] encourages some other centers [to evaluate SC blinatumomab in patients with MAPL]. This trial is going to open in 15 other centers. I'm aware that MPAL is not a public health crisis. It's rare, but there are 3 other centers that are joining us soon, and other patients across the country can join in [to help] finish this study and get the readout.

Until then, in the [WVU] press release, we provided a direct phone number and a direct email. We are happy to receive referrals from everywhere in the United States. We are also happy to receive referrals from international patients to put them in the study. We are happy to offer this to any eligible patients across the globe

References

1. WVU Cancer Institute first in the world to treat ultra-rare leukemia using novel subcutaneous immunotherapy. News Release. WVUMedicine. February 17, 2026. Accessed February 23, 2026. https://wvumedicine.org/news-feed/news-article/WVU-Medicine/Front-Page/wvu-cancer-institute-first-in-the-world-to-treat-ultra-rare-leukemia-using-novel-subcutaneous-immunotherapy/
2. Subcutaneous blinatumomab for treatment of adult patients with CD19-positive mixed phenotype acute leukemia (MPAL). ClinicalTrials.gov. Updated January 21, 2026. Accessed February 23, 2026. https://clinicaltrials.gov/study/NCT07222579