Encouraging news for treatment targeting retinitis pigmentosa

While most people probably wouldn’t put 2020 in their list of favorite years, it’s certainly turning out to be a good one for jCyte. Earlier this year jCyte entered into a partnership with global ophthalmology company Santen Pharmaceuticals worth up to $252 million. Then earlier this week they announced some encouraging results from their Phase 2b clinical trial.

Let’s back up a bit and explain what jCyte does and why it’s so important. They have developed a therapy for retinitis pigmentosa (RP), a rare vision destroying disease that attacks the light sensitive cells at the back of the eye. People are often diagnosed when they are in their teens and most are legally blind by middle age. CIRM has supported this therapy from its early stages into clinical trials.

This latest clinical trial is one of the largest of its kind anywhere in the world. They enrolled 84 patients (although only 74 were included in the final analysis). The patients had vision measuring between 20/80 and 20/800. They were split into three groups: one group was given a sham or placebo treatment; one was given three million human retinal progenitor cells (hRPCs), the kind attacked by the disease; and one was given six million hRPCs.

jCyte CEO Paul Bresge

In an article in Endpoints News, jCyte’s CEO Paul Bresge said there was a very specific reason for this approach. “We did enroll a very wide patient population into our Phase IIb, including patients that had vision anywhere from 20/80 to 20/800, just to learn which patients would potentially be the best responders.”

The results showed that the treatment group experienced improved functional vision and greater clarity of vision compared to the sham or placebo group. Everyone had their vision measured at the start and again 12 months later. For the placebo group the mean change in their ability to read an eye chart (with glasses on) was an improvement of 2.81 letters; for the group that got three million hRPCs it was 2.96 letters, and for the group that got six million hRPCs it was 7.43 letters.

When they looked at a very specific subgroup of patients the improvement was even more dramatic, with the six million cell group experiencing an improvement of 16.27 letters.

Dr. Henry Klassen

Dr. Henry Klassen, one of the founders of jCyte, says the therapy works by preserving the remaining photoreceptors in the eye, and helping them bounce back.

“Typically, people think about the disease as a narrowing of this peripheral vision in a very nice granular way, but that’s actually not what happens. What happens in the disease is that patients lose like islands of vision. So, what we’re doing in our tests is actually measuring […] islands that the patients have at baseline, and then what we’re seeing after treatment is that the islands are expanding. It’s similar to the way that one would track, let’s say a tumor, in oncology of course we’re looking for the opposite effect. We’re looking for the islands of vision to expand.”

One patient did experience some serious side effects in the trial but they responded well to treatment.

The team now plan on carrying out a Phase 3 clinical trial starting next year. They hope that will provide enough evidence showing the treatment is both safe and effective to enable them to get approval from the US Food and Drug Administration to make it available to all who need it.

A clear vision for the future

Dr. Henry Klassen and Dr. Jing Yang, founders of jCyte

When you have worked with a group of people over many years the relationship becomes more than just a business venture, it becomes personal. That’s certainly the case with jCyte, a company founded by Drs. Henry Klassen and Jing Yang, aimed at finding a cure for a rare form of vision loss called retinitis pigmentosa. CIRM has been supporting this work since it’s early days and so on Friday, the news that jCyte has entered into a partnership with global ophthalmology company Santen was definitely a cause for celebration.

The partnership could be worth up to $252 million and includes an immediate payment of $62 million. The agreement also connects jCyte to Santen’s global business and medical network, something that could prove invaluable in bringing their jCell therapy to patients outside the US.

Here in the US, jCyte is getting ready to start a Phase 2 clinical trial – which CIRM is funding – that could prove pivotal in helping it get approval from the US Food and Drug Administration.

As Dr. Maria Millan, CIRM’s President and CEO says, we have been fortunate to watch this company steadily progress from having a promising idea to developing a life-changing therapy.

“This is exciting news for everyone at jCyte. They have worked so hard over many years to develop their therapy and this partnership is a reflection of just how much they have achieved. For us at CIRM it’s particularly encouraging. We have supported this work from its early stages through clinical trials. The people who have benefited from the therapy, people like Rosie Barrero, are not just patients to us, they have become friends. The people who run the company, Dr. Henry Klassen, Dr. Jing Yang and CEO Paul Bresge, are so committed and so passionate about their work that they have overcome many obstacles to bring them here, an RMAT designation from the Food and Drug Administration, and a deal that will help them advance their work even further and faster. That is what CIRM is about, following the science and the mission.”

Paul Bresge, jCyte’s CEO says they couldn’t have done it without CIRM’s early and continued investment.

Paul Bresge, jCyte CEO

“jCyte is extremely grateful to CIRM, which was established to support innovative regenerative medicine programs and research such as ours.  CIRM supported our early preclinical data all the way through our late stage clinical trials.  This critical funding gave us the unique ability and flexibility to put patients first in each and every decision that we made along the way. In addition to the funding, the guidance that we have received from the CIRM team has been invaluable. jCell would not be possible without the early support from CIRM, our team at jCyte, and patients with degenerative retinal diseases are extremely appreciative for your support.”

Here is Rosie Barrero talking about the impact jCell has had on her life and the life of her family.