Experience to date in clinical study shows high clinical response rates for patients with visceral GvHD or GvHD that was refractory to standard of care treatment

SAN DIEGO, CA, USA I December 01, 2018 I Bellicum Pharmaceuticals, Inc. (NASDAQ:BLCM), a leader in developing novel, controllable cellular immunotherapies for cancers and orphan inherited blood disorders, today announced interim results from two multicenter trials of patients treated with rivo-celTM (rivogenlecleucel, formerly BPX-501) following a haploidentical stem cell transplant showing that rimiducid administration led to resolution of most cases of advanced Graft versus Host Disease (GvHD) or those who were refractory to standard of care treatment. The data were reviewed in a presentation today at the 60th Annual Meeting of the American Society of Hematology (ASH 2018) by Principal Investigator Reem Elfeky, M.D., UCL Great Ormond Street Hospital, London.

“These compelling data demonstrate the activity of rimiducid in combination with the CaspaCIDe® safety switch in the treatment of advanced or refractory GvHD based on the totality of our experience to date in pediatric patients who received rivo-cel,” said Rick Fair, Bellicum’s President & CEO. “The combination of rivo-cel and rimiducid may represent an exciting new way to more safely utilize allogeneic T cells to both clear residual cancer cells and improve control over infection following a stem cell transplant. These data also represent the strongest clinical validation to date of our industry-leading molecular switch technology.”

Study Design and Results

Patients in E.U. and U.S. multicenter trials were treated with rivo-cel (donor T cells genetically modified with the CaspaCIDe safety switch) following an αβT-cell receptor and B-cell depleted haploidentical stem cell transplant. Patients had malignant or nonmalignant disorders. No post-transplant pharmacologic GvHD prophylaxis was used.

Patients who developed visceral GvHD or were refractory to standard of care treatment were eligible to receive one dose of rimiducid (protocol later adjusted to allow for up to three doses of rimiducid). Of the 238 patients evaluable for GvHD, 54 patients (22.7%) developed acute GvHD (29 Grade II-IV; 7 Grade III-IV). 10 patients (5.6%) developed mild-to-severe chronic GvHD; 8 patients developed moderate-to-severe chronic GvHD. Results are summarized as follows:

  • 24 patients met the rimiducid efficacy-evaluable population definition
  • The best overall clinical response (CR/PR) within 7 days post rimiducid was an overall clinical response rate of 70% (16 responders)
  • A complete response (CR) or partial response (PR) to rimiducid was observed in 9 and 7 patients, respectively
  • Median time to initial response was 1 day (1-4 days)
  • 4 patients who achieved a partial or non-evaluable response within the first 7 days following rimiducid administration went on to achieve a complete response within 30 days following rimiducid administration
  • Nine patients (42.9%) received a second dose of rimiducid
    • The majority of patients were in partial response or no response at time of second dose of rimiducid
    • 2 patients in partial response at time of second dose of rimidicid went on to achieve a complete response
  • The median duration of standard GvHD treatment prior to rimiducid administration was 68 days

Differential Depletion of Activated T Cells

In a separate poster session, researchers presented data showing highly activated T cells express higher levels of iC9, making them more sensitive to rimiducid. This results in selectively depleting more GvHD-causing rivo-cel cells while sparing less alloreactive rivo-cel cells to continue to provide immunity and graft versus leukemia effect (GvL).

A copy of this ASH presentation will be made available in the Abstracts & Presentations section of the Company’s website. The Company expects to report topline final results in early 2019 followed by publication of a comprehensive data set.

Analyst and Investor Luncheon Event and Webcast
Bellicum will host a live and webcast analyst and investor luncheon event on December 3, 2018 at 12:00 p.m. – 1:30 p.m. PST in San Diego, CA. Featured speakers include Dr. Alice Bertaina, Associate Professor of Pediatrics, Stem Cell Transplantation, Lucile Packard Children’s Hospital at the Stanford School of Medicine, as well as Bellicum senior management. A webcast replay of the event will be available in the News & Events section of the Bellicum website, and available for at least two weeks following the event.

About Rivo-cel (BPX-501)
Rivo-celTM (rivogenlecleucel) is an allogeneic polyclonal T cell product designed to reduce relapse of leukemia following a stem cell transplant. The cell treatment contains a diverse repertoire of T cells which may contribute to a robust graft vs. leukemia effect. Rivo-cel’s antiviral benefits may also reduce morbidity and mortality in patients susceptible to infection following a transplant. The product’s CaspaCIDe® safety switch enables this approach by allowing physicians to reduce the number of alloreactive cells in the event of uncontrolled GvHD. Rivo-cel addresses a major unmet need in adult and pediatric leukemia, lymphoma and genetic blood disease patients following a haploidentical stem cell transplant.

About Bellicum Pharmaceuticals
Bellicum is a clinical stage biopharmaceutical company striving to deliver cures through controllable cell therapies. The Company’s next-generation product candidates are differentiated by powerful cell signaling technologies designed to produce more effective CAR-T, TCR and allogeneic T cell therapies. Its lead product candidate, rivo-celTM, is an allogeneic polyclonal T cell therapy that has shown promising clinical trial results in reducing leukemia relapse after a stem cell transplant. Bellicum’s lead GoCAR-T® candidate, BPX-601, is designed to be a more efficacious CAR-T cell product capable of overriding key immune inhibitory mechanisms. More information can be found at www.bellicum.com.​

SOURCE: Bellicum Pharmaceuticals