This summer, a company by the name of Cell Vault announced the launch of the first T-cell cryopreservation bank in the United States. Given the current groundswell in funding for autologous chimeric antigen receptor (CAR) T-cell (CAR-T) therapies, and the promise it holds for patients with treatment-refractory cancer, prospective cancer patients are likely to buy-in to the phenomenon — at least, those patients who can afford it. 

Cancer Therapy Advisor spoke with one of the scientific advisors for Cell Vault — Parameswaran Hari, MD, who is the Armand J. Quick/William F. Stapp Professor of Hematology at the Medical College of Wisconsin, Milwaukee — to ask him why he was motivated to work with the company. 

“One essential, non-negotiable component in existing T-cell immunotherapy is the ability to extract a sufficient amount of healthy T cells,” replied Dr Hari. Because of this current limitation, Dr Hari said he was intrigued by the idea of ensuring the availability of cells for everyone. “When the idea was pitched to me, we had a run of patients who did not have enough circulating T cells to collect and start CAR-T production.” If healthy cells could be stored before cancer occurs, said Dr Hari, then cures could be possible as techniques improve. 

Related Articles

Cell Vault seeks to make T-cell collection an easy process. After choosing a membership plan, the customer will receive a collection kit in the mail. Next, they will book a 5-minute blood-draw appointment with a “mobile phlebotomist teammate,” who will come to the customer’s home or place of work to take the sample. The phlebotomist will then overnight the package to the lab where it is processed and stored. 

Cancer Therapy Advisor sought a second opinion on Cell Vault’s business proposition from Bruce Levine, PhD, who is the Barbara and Edward Netter Professor in Cancer Gene Therapy,  the founding director of the clinical cell and vaccine production facility, and the deputy director of technology innovation and assessment in the Center for Cellular Immunotherapies at the University of Pennsylvania’s Perelman School of Medicine in Philadelphia.

Interestingly, Dr Levine expressed concern that a swift blood draw such as the one described by Cell Vault might not extract enough cells for future manufacturing processes: “The current methods of producing CAR-T cells require collection of hundreds of millions to billions of cells by apheresis, several hundred to a thousand times more than would be collected by a quick blood draw.”

He also questioned Cell Vault’s homepage proposition: What if a quick blood draw could save your life? “The framing of risk and potential benefit is unbalanced,” noted Dr Levine. “CAR T cells are currently approved only in relapsed/refractory diffuse large B-cell lymphoma and in relapsed/refractory pediatric and young adult acute lymphoid leukemia.” For currently approved indications, plus the indications expected to be approved by regulatory agencies within the next 3 years, the chance that a healthy person would be eligible to receive CAR-T therapy is less than 1 in 100,000 per year, he said.

Another unanswered question revolves around the persistence of cell viability. According to Dr Hari, there is precedent via the way stem cell products are currently collected that shows these cells incur only a small loss in viability; this loss is considered clinically insignificant in the case of stem cells. And, some of these cells have been banked for up to 2 decades.

“There are some data suggesting that the time to cryopreservation and the time in storage both affect T-cell responses to some extent.” Dr Hari acknowledged. Nevertheless, he said, “This should not affect CAR-T or [T-cell receptor] or vaccine cells created from the stored cells, since they are artificially programmed to mount a response.” 

While there is much more to learn about T-cell cryopreservation, Cell Vault’s launch in September 2019 is just one example of the bigger global commitment toward the broad use of CAR-T. 

Dr Hari is optimistic about the evolution of this treatment, and suggested people take action now — before a cancer diagnosis occurs. “One in three people is going to get cancer. When we are healthy is when we least think about it. Once cancer has developed and been treated with chemotherapy, the potential to expand and use cells declines.” 

He added, “Although storing healthy T cells and expanding them in time of need is mechanistically feasible, no clinical proof exists that patients have been successfully treated this way. We and others are doing viability and feasibility studies to produce CAR-T cells from cryopreserved healthy T cells and assessing their potential.”

[Interviews have been edited and condensed for clarity.]

Reference

Cell Vault joins the fight against cancer, raising $1 million in early funding for first-ever T-cell cryopreservation bank [news release]. San Francisco, CA: Cell Vault. Published July 16, 2019. Accessed August 1, 2019.

Disclosure: Bruce Levine declared he has financial interests in the form of intellectual property and patents in the field of cell and gene therapy, as well as relationships with: University of Pennsylvania Alliance with Novartis; CRC Oncology, Cure Genetics, Novartis, Terumo, Avectas, Brammer Bio, Incysus, Vycellix, and Tmunity Therapeutics.

Conflict of interest is managed in accordance with University of Pennsylvania policy and oversight.

Disclosure: Parameswaran Hari, MD, declared he is a scientific advisor to Cell Vault and has not received any financially significant payments or royalties at the time of publication.