CIRM-funded trial for blood cancer releases promising new data


A CIRM-funded trial conducted by Oncternal Therapeutics in collaboration with UC San Diego released an interim clinical data update for patients with mantle cell lymphoma (MCL), a type of blood cancer.

The treatment being developed involves an antibody called cirmtuzumab (named after yours truly) being used with a cancer fighting drug called ibrutinib. The antibody recognizes and attaches to a protein on the surface of cancer stem cells. This attachment disables the protein, which slows the growth of the blood cancer and makes it more vulnerable to anti-cancer drugs.

Here are the highlights from the new interim clinical data:

  • Patients had received a median of two prior therapies before participating in this study including chemotherapy; autologous stem cell transplant (SCT); autologous SCT and CAR-T therapy; autologous SCT and allogeneic SCT; and ibrutinib with rituximab, a different type of antibody therapy.
  • 6 of the 12 patients in the trial experienced a Complete Response (CR), which is defined as the disappearance of all signs of cancer in response to treatment.
  • All six CRs are ongoing, including one patient who has remained in CR for more than 21 months past treatment.
  • Four of the six patients achieved CRs within four months on the combination of cirmtuzumab and ibrutinib.
  • Of the remaining 6 patients, 4 experienced a Partial Response (PR), which is defined as a decrease in the extent of the cancer in the body.
  • The remaining two patients experienced Stable Disease (SD), which is defined as neither an increase or decrease in the extent of the cancer.

The full interim clinical data update can be viewed in the press release here.

Encouraging Progress for Two CIRM Supported Clinical Trials

This past Wednesday was Stem Cell Awareness Day, a day that is meant to remind us all of the importance of stem cell research and the potential it has to treat a wide variety of diseases. On this day, we also released an independent Economic Impact Report that showed how $10.7 Billion (yes, you read that right) was generated as a direct result of the the legacy we have built as a state agency that funds groundbreaking research.

Aside from the monetary incentive, which is an added bonus, the research we fund has made encouraging progress in the scientific field and has demonstrated the positive impact it can have on various disease areas. This week, two clinical trials supported by CIRM funding have released very promising updates.

Duchenne Muscular Dystrophy

Capricor Therapeutics, Inc. has presented positive results for a clinical trial related to a treatment for duchenne muscular dystrophy (DMD), a genetic disorder. DMD leads to progressive muscle degeneration and weakness due to its effect on a protein called dystrophin, which helps keep muscle cells intact.

The treatment that Capricor is testing is called CAP-1002 and consists of a unique population of cells that contain cardiac progenitor cells, a type of stem cell, that help encourage the regeneration of cells. CIRM funded an earlier clinical trial for this treatment.

The early results of this current trial describe how teens and young men in the advanced stages of DMD saw improvements in skeletal, lung, and heart measurements after receiving multiple doses of the treatment.

In a news release, Dr. Linda Marban, Chief Executive Officer of Capricor, expresses optimism for this clinical trial by saying,

“We are very pleased that the interim analysis from this double-blind placebo-controlled study, has demonstrated meaningful improvements across three clinically relevant endpoints in older patients with limited remaining treatment options.”

In the same news release, Dr. Craig McDonald, the national principal investigator for the trial, echoes the same sentiment by stating,

“The results from this trial to date are very promising in that the cells appear to positively impact skeletal, pulmonary and cardiac assessments in older DMD patients who have few, if any, remaining treatment options. We are eager to meet with the FDA to discuss the next steps for this promising program.”

Mantle Cell Lymphoma

Additionally, Oncternal Therapeutics has decided, because of positive results, to open an expansion of its CIRM-funded clinical trial aimed at treating patients with mantle cell lymphoma (MCL). The treatment involves an antibody called cirmtuzumab, named after us, in combination with a drug called ibrutinib.

The preliminary results were from the first six patients with MCL that were treated in the trial. One patient with MCL, who had relapsed following an allogeneic stem cell transplant, experienced a confirmed complete response (CR) after three months of cirmtuzumab plus ibrutinib treatment. This complete response appears to be sustained and has been confirmed to be ongoing after completing 12 months of the combination treatment. A second confirmed complete response occurred in a patient who had progressive disease after failing several different chemotherapy regimens, bone marrow transplant and CAR-T therapy. 

In a news release, Dr. Hun Lee, an investigator in the trial, states that,

“It is encouraging to see that the drug has been well tolerated as well as the early signal of efficacy of cirmtuzumab with ibrutinib in MCL, particularly the rapid and durable complete responses of the heavily pre-treated patients after three months of therapy, which is an unusually fast response in this patient population.”

CIRM-funded clinical trial shows encouraging results for patients with chronic lymphocytic leukemia & mantle cell lymphoma

Illustration courtesy of Oncternal Therapeutics

I often joke that my job here at CIRM is to be the official translator for the stem cell agency. I have to translate complex science into everyday English that people without a science background – that includes me – can understand.

Think I’m joking? Try making sense of this.

See what I mean. If you are a scientist this is not only perfectly clear, it’s also quite exciting. But for the rest of us……..

Actually, it is really quite exciting news. It’s about a CIRM-funded clinical trial being run by Oncternal Therapeutics to treat people with chronic lymphocytic leukemia (CLL), a kind of cancer where our body makes too many white blood cells. The study is using a combination therapy of Cirmtuzumab (a monoclonal antibody named after us because we helped fund its development) and ibrutinib, a conventional therapy used to treat cancers like CLL.

Cirmtuzumab recognizes and then attaches itself to a protein on the surface of cancer stem cells that the cancer needs to survive and spread. This attachment disables the protein (called ROR1) which slows the growth of the leukemia and makes it more vulnerable to anti-cancer drugs like ibrutinib.

In this Phase 1/2 clinical trial 12 patients were given the combination therapy for 24 weeks or more, making them eligible to determine how effective, or ineffective, the therapy is:

  • 11 of the 12 patients had either a partial response – meaning a reduction in the amount of detectable cancer – or a complete response to the treatment – meaning no detectable cancer.
  • None of the patients saw their cancer spread or grow
  • Three of the patients completed a year of treatment and they all showed signs of a complete response including no enlarged lymph nodes and white blood cell counts in the normal range.  

The combination therapy is also being used to treat people with Mantle Cell Lymphoma (MCL), a rare but fast-growing form of blood cancer. The results from this group, while preliminary, are also encouraging. One patient, who had experienced a relapse following a bone marrow transplant, experienced a complete response after three months of cirmtuzumab and ibrutinib.  

The data on the clinical trial was presented at a poster session (that’s the poster at the top of this blog) at the annual meeting of the American Society of Clinical Oncology.

In a news release Dr. James Breitmeyer, the President & CEO of Oncternal, said the results are very encouraging:  

“These data presented today, taken together with an earlier Phase 1 study of cirmtuzumab as a monotherapy in relapsed/refractory CLL, give us increased confidence in the potential for cirmtuzumab as a treatment for patients with ROR1-expressing lymphoid malignancies, particularly in combination with ibrutinib as a potential treatment for patients with CLL and MCL. We believe that the data also help to validate the importance of ROR1 as a therapeutic target,”