105 patients treated with BPX-501 in BP-004 trial; 85 with more than 100 days of follow-up
Company reports encouraging results with BPX-501 in high-risk pediatric leukemia patients

SAN DIEGO, CA, USA I December 5, 2016 I Bellicum Pharmaceuticals, Inc. (Nasdaq:BLCM), a clinical stage biopharmaceutical company focused on discovering and developing novel cellular immunotherapies for cancers and orphan inherited blood disorders, presented a review of results to date from its multicenter BP-004 clinical trial of BPX-501 in the pediatric setting, and provided an update on the regulatory pathway for product registration in Europe at an investor and analyst event held today. Clinical results on BPX-501 in children with hematological malignancies were also presented in a poster presentation at the American Society of Hematology (ASH) annual meeting.

“We have made significant progress with our BPX-501 program since initiating the BP-004 clinical trial in children two years ago,” commented Tom Farrell, President and CEO of Bellicum Pharmaceuticals. “To date, we have treated more than 100 patients at leading pediatric transplant centers in Europe and the U.S. Results thus far have been impressive—including GvHD- and disease-free outcomes in children with a range of blood cancers and genetic diseases, as reported this weekend in several presentations at ASH. We’re also pleased with the progress we’ve made in formalizing an expedient pathway to regulatory approval in Europe with BPX-501 to treat both malignant and nonmalignant diseases. We look forward to providing an update on our U.S. regulatory path in the first half of 2017.”

Overall Summary of Results of BP-004 Study with BPX-501 (n=85)

The Company presented a review of results to date of the BP-004 study in pediatric patients with malignant and nonmalignant diseases who underwent a haploidentical hematopoietic stem cell transplant (HSCT) followed by an add-back of genetically modified BPX-501 T cells. Eighty-five patients have been treated with BPX-501 at multiple U.S. and European sites and followed for at least 100 days (out of a total of 105 patients treated to date). Only one case of transplant-related mortality has been reported, unrelated to BPX-501 cells, and none out of 51 patients with nonmalignant disorders. Compared to T-depleted haplo-transplants alone, results have also shown significantly faster immune recoveries, as well as reduced viral infections and reactivation, and reductions in time to hospital discharge and re-hospitalizations due to infection. In five cases where uncontrolled acute GvHD was attributable to BPX-501 cells, rimiducid was administered and symptoms resolved.

Results have been consistent across a range of diseases and disorders where allogeneic HSCT is recognized as curative, including hemoglobinopathies such as Beta Thalassemia Major (β0β0), Sickle Cell Disease and Diamond-Blackfan Anemia; Primary Immune Deficiencies such as Severe Combined Immune Deficiency (“Bubble boy” disease) and Wiskott-Aldrich syndrome; leukemias and lymphomas; and bone marrow failure syndromes. The Company also reported that of six refractory AML patients treated under compassionate use because of their active disease and not included in the BP-004 summary data, 4 remain alive and in remission, including two who are now 11 and 20 months post-transplant.

Regulatory Update for BPX-501 in the European Union

The Company also announced today that the protocol assistance provided by the European Medicines Agency (EMA) for the registration study of BPX-501 in Europe is complete, and the Company is finalizing plans for the BP-004 trial extension. The Company will continue enrolling up to 40 additional patients with malignant and nonmalignant diseases in the trial. Concurrent with this study, the Company will initiate a comparator trial of malignant and nonmalignant patients receiving a matched unrelated donor (MUD) HSCT. This trial will include both retrospective patients and up to 40 prospective patients. The primary endpoint will be event-free survival (death, GvHD and infection) at 6 months.

Bellicum anticipates that it could pursue approval in the EU under the “exceptional circumstances” provision. Exceptional circumstances may be granted for medicines that treat very rare diseases, or where controlled studies are impractical or not consistent with accepted principles of medical ethics. The Company continues to discuss the regulatory path to approval in the U.S. with FDA and expects to provide an update in the first half of 2017.

Also today at the ASH 2016 annual meeting, updated results were presented in patients with acute myeloid leukemia (AML).

AML Highlights (Abstract #4683)

“T-cell depleted HLA-haploidentical allogeneic hematopoietic stem cell transplantation (haplo-HSCT) followed by donor lymphocyte infusion with T cells transduced with the inducible caspase 9 (iC9) suicide gene in children with hematological malignancies”

In a poster session, investigators presented data in 33 children with AML who received an α/β TCR-depleted haplo-HSCT and BPX-501 cells. The data indicate that infusion of BPX-501 results in low non-relapse mortality, and low rates of acute and chronic Graft versus Host Disease. Median follow-up was 8 months (range: 1–19 months). All 33 patients were high-risk CR1 (6/33) or CR2 (27/33). Study outcomes include:

   All 33 patients engrafted with no secondary graft failure

   One patient with steroid-resistant Grade II skin acute GvHD received rimiducid with complete resolution of disease in 24 hours

   One treatment-related mortality from chronic GvHD was determined to be allograft-related and not from BPX-501 T cells

   3 of 33 patients have relapsed; the probability of disease-free survival at 15 months is 83.6%

A replay of the investor and analyst meeting held today can be accessed from the News & Events section of the Bellicum website. An archived version of the webcast will be available for at least two weeks following the event.

About BPX-501

BPX-501 is an adjunct T-cell therapy administered after allogeneic HSCT, comprising genetically modified donor T cells incorporating Bellicum’s CaspaCIDe® safety switch. It is designed to provide a safety net to eliminate alloreactive BPX-501 T cells (via administration of activator agent rimiducid) should uncontrollable GvHD occur. This enables physicians to more safely perform stem cell transplants by adding back BPX-501 engineered T cells to speed immune reconstitution and provide control over viral infections, without unacceptable risk of uncontrollable GvHD. The ongoing BP-004 Phase 1/2 clinical study of BPX-501 is being conducted at transplant centers in the U.S. and Europe.

About Bellicum Pharmaceuticals

Bellicum is a clinical stage biopharmaceutical company focused on discovering and developing cellular immunotherapies for cancers and orphan inherited blood disorders. Bellicum is using its proprietary Chemical Induction of Dimerization (CID) technology platform to engineer and control components of the immune system. Bellicum is developing next-generation product candidates in some of the most important areas of cellular immunotherapy, including hematopoietic stem cell transplantation (HSCT), and CAR T and TCR cell therapies. More information can be found at www.bellicum.com.

SOURCE: Bellicum Pharmaceuticals