BlueRock Therapeutics' Parkinson Disease Cell Therapy Bemdaneprocel Shows Safety and Efficacy at 18 Months Posttreatment

BlueRock Therapeutics’ bemdaneprocel (BRT-DA01), an investigational neuronal cell therapy intended to treat Parkinson disease (PD), has continued to show safety and promising initial results in terms of efficacy at 18 months posttreatment in patients who received the therapy in an ongoing phase 1 clinical trial (NCT04802733).¹

BlueRock stated that at 18 months posttreatment, bemdaneprocel remained well-tolerated and no major safety issues had occurred in the treated patients, which included 12 patients in total across the lower dose (0.9 million cells per putamen) cohort A (n = 5) and the higher dose (2.7 million cells per putamen) cohort B (n = 7). Furthermore, the transplanted cells survived and engrafted in the brain and following the cessation of immune suppression therapy at 12 months posttreatment as per study protocol F-DOPA signal was shown to continue increasing.

The study’s exploratory end points for efficacy include the change in waking hours in the Hauser Diary’s “OFF” state, defined by that tool as a state in which patients experience a worsening of their symptoms that stands in contrast to the “ON” state in which symptoms are well-controlled. At 18 months posttreatment, the patients treated at the high dose experienced a mean increase from baseline of 2.7 hours in the “ON” state and a 2.7 hour decrease for time in the “OFF” state. For patients treated at the low dose, a mean increase of 0.2 hours in the “ON” state compared to baseline was observed at 18 months posttreatment, with a corresponding mean decrease of 0.8 hours spent in the “OFF” state. The study also looks at the change from baseline in the MDS-Unified Parkinson's Disease Rating Scale Part III (MDS-UPDRS Part III) motor sub-score in the “OFF” state. At 18 months posttreatment, patients who received the high dose of bemdaneprocel achieved a 23 point reduction compared to baseline on the MDS-UPDRS Part III and patients who received the low dose achieved an 8.6 point reduction. BlueRock characterized the low dose group’s improvement as “mild”. Alongside the data update, the company noted that it anticipates enrollment of patients in a phase 2 clinical study to begin later in 2024.

“It’s exciting that bemdaneprocel met safety and tolerability criteria at 12 months, and now the 18-month results suggest that these allogeneic cells survive and have potentially positive effects even after discontinuation of immunosuppressants,” Claire Henchcliffe, MD, the chair of the University of California, Irvine, School of Medicine Department of Neurology and a principal investigator for the trial, said in a statement.¹ “We should not overinterpret results of a phase 1 study, but this is a promising step that deserves to be followed up with further studies.”

The 18-month data continued the positive trend seen in data from the 1-year timepoint, which was presented by Heathcliffe at the 2023 International Congress of Parkinson’s Disease and Movement Disorders (MDS), held August 27-31, in Copenhagen.² At that time 31 total adverse events (AEs) were reported in the low dose cohort, but all were considered mild to moderate in severity save for 1 case of fall. No serious AEs were attributed to bemdaneprocel. Although, 2 unrelated serious AEs of seizure were attributed to the surgical procedure and 1 COVID-19 case occurred. Bemdaneprocel is administered via bilateral surgical transplantation to the to the postcommissural putamen and consists of dopaminergic neuron precursors derived from pluripotent embryonic stem cells.¹

“We are on the leading edge in the research for new treatment options for Parkinson’s disease as bemdaneprocel, the most clinically advanced pluripotent stem derived cell therapy candidate to date for this disease, continues to show positive trends,” Christian Rommel, PhD, a member of the Executive Committee of Bayer’s Pharmaceuticals Division and head of Research and Development, added to the statement.¹ “There are good reasons to be optimistic about these early data, and we are excited to move to phase 2 later this year.”

REFERENCES
1. BlueRock Therapeutics phase I clinical trial for Parkinson’s disease continues to show positive trends at 18 months. News release. Bayer AG and BlueRock Therapeutics LP. March 6, 2024. Accessed March 22, 2024. https://www.bluerocktx.com/bluerock-therapeutics-phase-i-clinical-trial-for-parkinsons-disease-continues-to-show-positive-trends-at-18-months/
2. Henchcliffe C, Sarva H, Lozano A, et al. Dopaminergic neuronal cell therapy for Parkinson’s disease: results from a phase 1 study of bemdaneprocel. Presented at 2023 MDS Congress; August 27-31; Copenhagen, Denmark. Abstract 65.