How developing a treatment for a rare disease could lead to therapies for other, not-so-rare conditions

Logan Lacy, a child with AADC Deficiency: Photo courtesy Chambersburg Public Opinion

Tomorrow, the last day in February, is Rare Disease Day. It’s a day dedicated to raising awareness about rare diseases and the impact they have on patients and their families.

But the truth is rare diseases are not so rare. There are around 7,000 diseases that affect fewer than 200,000 Americans at any given time. In fact, it’s estimated that around one in 20 people will live with a rare disease at some point in their lives. Many may die from it.

This blog is about one man’s work to find a cure for one of those rare diseases, and how that could lead to a therapy for something that affects many millions of people around the world.

Dr. Krystof Bankiewicz; Photo courtesy Ohio State Medical Center

Dr. Krystof Bankiewicz is a brain surgeon at U.C. San Francisco and The Ohio State University. He is also the President and CEO at Brain Neurotherapy Bio and a world expert in delivering gene and other therapies to the brain. More than 20 years ago, he began trying to develop a treatment for Parkinson’s disease by looking at a gene responsible for AADC enzyme production, which plays an important role in the brain and central nervous system.  AADC is critical for the formation of serotonin and dopamine, chemicals that transmit signals between nerve cells, the latter of which plays a role in the development of Parkinson’s disease.

While studying the AADC enzyme, Dr. Bankiewicz learned of an extremely rare disorder where children lack the AADC enzyme that is critical for their development.  This condition significantly inhibits communication between the brain and the rest of the body, leading to extremely limited mobility, muscle spasms, and problems with overall bodily functions.  As a result of this, AADC deficient children require lifelong care, and particularly severe cases can lead to death in the first ten years of life.

“These children can’t speak. They have no muscle control, so they can’t do fundamental things such as walking, supporting their neck or lifting their arms,” says Dr. Bankiewicz. “They have involuntary movements, experience tremendously painful spasms almost like epileptic seizures. They can’t feed themselves and have to be fed through a tube in their stomach.”

So, Dr. Bankiewicz, building on his understanding of the gene that encodes AADC, developed an experimental approach to deliver a normal copy, injected directly into the midbrain, the area responsible for dopamine production. The DDC gene was inserted into a virus that acted as a kind of transport, carrying the gene into neurons, the brain cells affected by the condition. It was hoped that once inside, the gene would allow the body to produce the AADC enzyme and, in turn, enable it to produce its own dopamine .

And that’s exactly what happened.

“It’s unbelievable. In the first treated patients their motor system is dramatically improved, they are able to better control their movements, they can eat, they can sleep well. These are tremendous benefits. We have been following these children for almost three years post-treatment, and the progression we see doesn’t stop, it keeps going and we see these children keep on improving. Now they are able to get physical therapy to help them. Some are even able to go to school.”

For Dr. Bankiewicz this has been decades in the making, but that only makes it all the more gratifying: “This doesn’t happen very often in your lifetime, to be able to use all your professional experience and education to help people and see the impact it has on people’s lives.”

So far he has treated 20 patients from the US, UK and all over the world.

But he is far from finished.

Already the therapy has been given Orphan Drug Designation and Regenerative Medicine Advanced Therapy designation by the US Food and Drug Administration. The former is a kind of financial incentive to companies to develop drugs for rare diseases. The latter gives therapies that are proving to be both safe and effective, an accelerated path to approval for wider use. Dr. Bankiewicz hopes that will help them raise the funds needed to treat children with this rare condition.  “We want to make this affordable for families. We are not in this to make a profit; we want to get foundations and maybe even pharmaceutical companies to help us treat the kids, so they don’t have to cover the full costs themselves.”

CIRM has not funded any of this work, but the data and results from this research were important factors in our Board awarding Dr. Bankiewicz more than $5.5 million to begin a clinical trial for Parkinson’s disease. Dr. Bankiewicz is using a similar approach in that work to the one he has shown can help children with AADC deficiency.

While AADC deficiency may only affect a few hundred children worldwide, it’s estimated that Parkinson’s affects more than ten million people; one million of those in the US alone.  Developing this gene therapy technique in a rare disease, therefore, may ultimately benefit large populations of patients.

So, on this Rare Disease Day, we celebrate Dr. Bankiewicz and others whose compassion and commitment to finding treatments to help those battling rare conditions are helping change the world, one patient at a time.

You can follow the story of one child treated by Dr. Bankiewicz here.

200 years later, the search for a cure for Parkinson’s continues

On the surface, actor Michael J. Fox, singer Neil Diamond, civil rights activist Jesse Jackson and Scottish comedian Billy Connolly would appear to have little in common. Except for one thing. They all have Parkinson’s Disease (PD).

Their celebrity status has helped raise public awareness about the condition, but studies show that awareness doesn’t amount to an understanding of PD or the extent to which it impacts someone’s life. In fact a study in the UK found that many people still don’t think PD is a serious condition.

To try and help change that people around the world will be holding events today, April 11th, World Parkinson’s Day.

The disease was first described by James Parkinson in 1817 in “An Essay on the Shaking Palsy”. In the essay Parkinson described a pattern of trembling in the hands and fingers, slower movement and loss of balance. Our knowledge about the disease has advanced in the last 200 years and now there are treatments that can help slow down the progression of the disease. But those treatments only last for a while, and so there is a real need for new treatments.  

That’s what Jun Takahashi’s team at Kyoto University in Japan hope to provide. In a first-of-its-kind procedure they took skin cells from a healthy donor and reprogrammed them to become induced pluripotent stem cells (iPSCs), or stem cells that become any type of cell. These iPSCs were then turned into the precursors of dopamine-producing neurons, the cells destroyed by PD, and implanted into 12 brain regions known to be hotspots for dopamine production.

The procedure was carried out in October and the patient, a male in his 50s, is still healthy. If his symptoms continue to improve and he doesn’t experience any bad side effects, he will receive a second dose of dopamine-producing stem cells. Six other patients are scheduled to receive this same treatment.

Earlier tests in monkeys showed that the implanted stem cells improved Parkinson’s symptoms without causing any serious side effects.

Dompaminergic neurons derived from stem cells

Scientists at UC San Francisco are trying a different approach, using gene therapy to tackle one of the most widely recognized symptoms of PD, muscle movement.

In the study, published in the journal Annals of Neurology, the team used an inactive virus to deliver a gene to boost production of dopamine in the brain. In a Phase 1 clinical trial 15 patients, whose medication was no longer able to fully control their movement disorder, were treated with this approach. Not only were they able to reduce their medication – up to 42 percent in some cases – the medication they did take lasted longer before causing dyskinesia, an involuntary muscle movement that is a common side effect of the PD medication.

In a news article Dr. Chad Christine, the first author of the study, says this approach may also help reduce other symptoms.

“Since many patients were able to substantially reduce the amount of Parkinson’s medications, this gene therapy treatment may also help patients by reducing dose-dependent side effects, such as sleepiness and nausea.” 

At CIRM we have a long history of funding research into PD. Over the years we have invested more than $55 million to try and develop new treatments for the disease.

In June 2018, the CIRM Board awarded $5.8 million to UC San Francisco’s Krystof Bankiewicz and Cedars-Sinai’s Clive Svendsen. They are using neural progenitor cells, which have the ability to multiply and turn into other kinds of brain cells, and engineering them to express the growth factor GDNF which is known to protect the cells damaged in PD. The hope is that when transplanted into the brain of someone with PD, it will help slow down, or even halt the progression of the disease. 

The CIRM funding will hopefully help the team do the pre-clinical research needed to get the FDA’s go-ahead to test this approach in a clinical trial. 

David Higgins, CIRM Board member and Patient Advocate for Parkinson’s Disease

At the time of the award David Higgins, PhD, the CIRM Board Patient Advocate for Parkinson’s Disease, said: “One of the big frustrations for people with Parkinson’s, and their families and loved ones, is that existing therapies only address the symptoms and do little to slow down or even reverse the progress of the disease. That’s why it’s important to support any project that has the potential to address Parkinson’s at a much deeper, longer-lasting level.”

But we don’t just fund the research, we try to bring the scientific community together to help identify obstacles and overcome them. In March of 2013, in collaboration with the Center for Regenerative Medicine (CRM) of the National Institutes of Health (NIH), we held a two-day workshop on cell therapies for Parkinson’s Disease. The experts outlined the steps needed to help bring the most promising research to patients.

Around one million Americans are currently living with Parkinson’s Disease. Worldwide the number is more than ten million. Those numbers are only expected to increase as the population ages. There is clearly a huge need to develop new treatments and, hopefully one day, a cure.

Till then days like April 11th will be an opportunity to remind ourselves why this work is so important.