World Parkinson’s Day: advancing treatment options with cell therapies, gene therapies and novel biologics
Over 11 million people worldwide are estimated to live with Parkinson’s disease, the fastest growing neurological condition in the world. Taking place annually on 11 April, World Parkinson’s Day aims to promote research and support for those living with the condition.
Parkinson’s disease, a progressive neurodegenerative disorder characterized by tremors, stiffness and slowed movement, is primarily caused by the loss of dopamine-producing neurons in the brain. Current treatments, including levodopa and dopamine agonists, can effectively reduce symptoms, especially in the early stages. However, they do not slow or stop disease progression and their effectiveness typically diminishes over time.
Rather than just managing symptoms, regenerative approaches aim to repair or replace the neurons that are lost or damaged in Parkinson’s disease. These therapies include:
- Cell-based therapies to replace dopamine-producing neurons using stem cells or reprogrammed patient cells
- Gene therapies that enhance dopamine production, correct faulty genes or deliver neuroprotective factors
- Novel biologics, including exosomes and neurotrophic factors, designed to halt degeneration or promote repair
While these approaches are still largely in development, they offer the potential to modify the course of Parkinson’s disease and maybe one day, reverse it. Below, we explore some regenerative and advanced therapies for Parkinson’s disease that have caught our eye.
Cell therapies
Embryonic stem cell-derived dopaminergic precursors
Bemdaneprocel is an investigational allogeneic cell therapy developed by BlueRock Therapeutics (MA, USA). It aims to replace the dopamine producing neurons that are lost in Parkinson’s disease by surgically transplanting neuron precursors derived from human embryonic pluripotent stem cells into the brain. The implanted cells develop into mature dopamine neurons and have the potential to integrate into existing neural networks, potentially restoring motor and non-motor functions impaired by the disease.
In 2021, bemdaneprocel received Fast Track Designation and in 2024, Regenerative Medicine Advanced Therapy (RMAT) designation from the US Food and Drug Adminstration (FDA; MD, USA). In January 2025, BlueRock announced its plans to progress to Phase III trials following the completion and discussion of its Phase I trial data with the FDA under its RMAT designation.
iPSC-derived dopaminergic neurons
Aspen Neuroscience (CA, USA) is developing ANPD001, an autologous induced pluripotent stem cell (iPSC)-based therapy for Parkinson’s disease. The approach begins with collecting a patient’s skin cells, which are reprogrammed into iPSCs and then differentiated into dopaminergic neurons, which are transplanted into the patient’s brain. This personalized approach aims to restore lost neuronal function while minimizing the risk of immune rejection.
Aspen received FDA clearance for its Investigational New Drug application for ANPD001 in August 2023 and is currently under investigation in the Phase I/II ASPIRO trial (NCT06344026).
Gene therapies
Delivering human glial cell line-derived neurotrophic factor
AB-1005, developed by AskBio (NC, USA), is an investigational gene therapy that utilizes an adeno-associated virus serotype 2 (AAV2) vector to deliver the human glial cell line-derived neurotrophic factor gene directly into the putamen to promote the survival and differentiation of dopaminergic neurons, potentially slowing disease progression.
In a Phase Ib clinical trial, a one-time bilateral administration of AB-1005 was well-tolerated, with no serious adverse events attributed to the therapy. Encouraged by these results, AskBio initiated the Phase II REGENERATE-PD trial (NCT06285643) to further assess the efficacy and safety of AB-1005 in individuals with moderate Parkinson’s disease. In February 2025, the FDA granted AB-1005 RMAT designation.
Restoring the function of GBA1
PR001, developed by Prevail Therapeutics (a subsidiary of Eli Lilly and Company; NY, USA), is an investigational gene therapy for Parkinson’s disease patients with mutations in the GBA1 gene. Utilizing an adeno-associated virus serotype 9 (AAV9) vector, PR001 delivers a functional copy of the GBA1 gene directly into the central nervous system via intracisternal administration. This approach aims to restore glucocerebrosidase enzyme activity, addressing the underlying lysosomal dysfunction associated with GBA1 mutations.
The ongoing Phase I/IIa PROPEL trial (NCT04127578) is evaluating the safety and potential efficacy of PR001 in individuals aged 35 to 80 with moderate to severe PD-GBA. The FDA granted Fast Track designation for PR001 in the treatment of Parkinson’s disease with GBA1 mutations in October 2020.
Novel biologics
Cerebral Dopamine Neurotrophic Factor
Cerebral Dopamine Neurotrophic Factor (CDNF) is a neurotrophic factor that promotes the survival and function of dopamine-producing neurons, offering a disease-modifying approach to Parkinson’s disease. Herantis Pharma (Espoo, Finland) developed an intracerebral delivery method for CDNF via a surgically implanted drug delivery system, aiming to bypass the blood–-brain barrier. In a 2020 first-in-human Phase I–II clinical trial (NCT03295786), CDNF was shown to be safe and well-tolerated, with exploratory data suggesting possible signals of neurorestorative effects.
The company has since transitioned its focus to a next-generation, non-invasive formulation called HER-096, a small synthetic peptide derivative of CDNF designed for subcutaneous administration. The safety and tolerability of HER-096 is currently being investigated in a Phase Ib trial (NCT06659562), which is expected to reach completion in the second half of 2025.
Exosome-based therapies
Exosome-based therapies could be of great benefit in Parkinson’s disease treatment due to their natural ability to cross the blood-–brain barrier and deliver therapeutic cargo, such as proteins, RNA or small molecules. For instance, exosomes enriched with brain-derived neurotrophic factor (BDNF) were shown to suppress apoptosis and ferroptosis in dopaminergic neurons, enhancing neuronal survival and stability in a mouse model of Parkinson’s disease [1].
Looking Ahead
While these therapies are not yet widely available, they represent a significant shift in how we might treat Parkinson’s disease. From replacing damaged neurons to protecting the brain with gene therapies, regenerative medicine offers real hope for altering the course of neurodegenerative diseases. As clinical trials progress and technologies evolve, these approaches could pave the way for a new era in Parkinson’s treatment.
