Niemann-Pick disease type C: testing a potential new drug treatment

Niemann-Pick disease type C (NPC) belongs to a group of over 70 rare inherited conditions known as lysosomal storage diseases.¹ Primarily affecting children, NPC is a progressive disease and sadly many do not survive into adulthood. Although the age of diagnosis and how quickly symptoms worsen varies, in the most severe cases babies will lose their lives only a few months after birth. Professor Frances Platt of the University of Oxford is carrying out laboratory tests to find out if a drug currently used to treat multiple sclerosis could be an effective new treatment for NPC. Her hope is that one day this drug could help transform the lives of children born with this devastating condition.

Action Medical Research, the Niemann-Pick Research Foundation and Niemann-Pick UK are funding this study, together with NPSuisse and Niemann-Pick de Fuenlabrada.

How are children’s lives affected now?

Children with Niemann-Pick disease type C (NPC) most often have a faulty gene that codes for a protein called NPC1 found in lysosomes, the cell’s recycling centre that breaks down waste materials. Without this protein, lysosomes can’t work properly, and unwanted cholesterol and other fatty substances build up inside cells causing nerve damage.

“Children with NPC are often initially seen to be clumsy, but this will slowly get worse over time and they will go on to have major problems coordinating movements such as walking. They will also lose their speech and experience a gradual decline in their intellectual ability,” says Professor Platt.

The age of onset and disease progression vary greatly from person to person – some children develop symptoms very early on in life whereas others may remain undiagnosed well into adulthood.

“Sadly, there is no cure for NPC – and current treatment options are extremely limited,” says Professor Platt. “New treatments are desperately needed that can slow down or stop the progression of the disease.”

How could this research help?

“We are aiming to repurpose an existing drug that is already used to treat multiple sclerosis to develop a much-needed new treatment for NPC patients,” says Professor Platt.

Her collaborator Professor Sarah Spiegel at Virginia Commonwealth University, USA, has unexpectedly found that this drug can boost the levels of the NPC1 protein, suggesting it might also improve lysosomal function and be useful for treating patients with NPC.

“We will now carry out a series of laboratory experiments, in collaboration with Professor Spiegel, to find out whether it can improve the symptoms of NPC,” says Professor Platt.

The researchers will also test the effectiveness of combining this with the only currently approved drug (miglustat) for treating NPC. This works by blocking the formation of unwanted fatty substances that accumulate in cells, slowing the progression of the disease.

“We hope that using both drugs together could prove a powerful combination, particularly because they each target different biological processes involved in the disease,” says Professor Platt.

Should their results look promising, the researchers hope to move quickly into clinical trials involving patients with NPC.

References

Platt FM et al., Lysosomal storage diseases. Nature Reviews Disease Primers 2018; 4, Article number: 27