Netherlands-based VectorY Therapeutics has initiated a first-in-human clinical trial of VTx-002, an investigational gene therapy targeting amyotrophic lateral sclerosis (ALS) in a Phase 1/2 multicenter study. The experimental therapy offers a unique intracisternal administration strategy targeting motor neuron degeneration.

VTx-002 is a first-in-class, vectorized antibody therapeutic developed to selectively target toxic, misfolded, or aggregated forms of TAR DNA-binding protein 43 (TDP-43), while sparing the protein’s normal physiological function. Pathological TDP-43 aggregation is a central driver of disease biology in the vast majority of ALS cases.

The therapy is delivered via an adeno-associated virus (AAV) vector, enabling sustained in vivo expression of the therapeutic antibody within target cells. This strategy is intended to reduce TDP-43 aggregation, correct downstream RNA mis-splicing abnormalities, and restore normal nuclear function in affected motor neurons.

The open-label trial will enroll patients with ALS while excluding individuals with FUS or SOD1 mutations, reflecting the therapy’s mechanistic focus on TDP-43–driven disease. The study includes a dose-escalation design, with corticosteroids permitted as rescue medication, highlighting potential immune-response considerations typical of CNS-directed gene therapies.

Research context

The ALS therapeutic landscape remains highly challenging, with few disease-modifying options available. Current standard-of-care treatments, including riluzole and edaravone, provide only modest clinical benefit. More recently, Biogen’s tofersen became the first approved gene therapy for SOD1-linked ALS in 2023, marking a significant milestone for genetically defined subtypes of the disease.

A growing number of experimental approaches are targeting TDP-43–related pathology, spanning gene therapies, small molecules, and emerging cell-based strategies. Dewpoint Therapeutics has selected a small molecule TDP-43 condensate modulator for development, aiming to restore normal TDP-43 function by modulating “biomolecular condensates”. The program is being advanced in collaboration with in partnership with Mitsubishi Tanabe Pharma.

Meanwhile, QurAlis Corporation has initiated a Phase I trial for QRL-201, precision therapy designed to restore expression of STMN2, a critical neuronal protein whose loss is directly linked to TDP-43 dysfunction. Together, these programs underscore increasing industry focus on targeting shared molecular drivers of ALS beyond genetically defined subpopulations.