Kite Pharma’s CAR-T drug begins LA hospital trial in children

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Hoping to match if not best rival Juno Therapeutics’ ($JUNO) recent CAR-T success in ALL, Kite Pharma ($KITE) has enrolled the first patient in its new early-stage study for children with the disease.

The Phase I/II single arm study will focus on children and young adults with relapsed or resistant acute lymphoblastic leukemia (ALL) who will be treated with Kite’s KTE-C19--one of the hottest new experimental cancer therapies.

The study, which will be undertaken at Children's Hospital Los Angeles as well as at other sites, uses Kite’s lead CAR-T immunotherapy.

This therapy works by extracting T cells from a patient's blood and equip them with targeting mechanisms called chimeric antigen receptors--which seek out and bind to proteins expressed by cancer cells. KTE-C19 is specifically crafted by removing patients' T cells and genetically engineering them to home in on the protein CD19, expressed by a variety of blood cancers.

The Santa Monica-based biotech is partnering with the Children's Hospital to offer the therapy to patients from 2 - 21 years old who have the CD-19 protein on their ALL cells. The study will look for efficacy signals via remission rates, and measure overall safety--with data set to be reported in June 2017.

The first patient in the trial was enrolled on April 28, said Dr. Alan Wayne, director of the hospital's Children's Center for Cancer and Blood Diseases, speaking to the San Diego Tribune.

"These are major steps forward in developing targeted therapies for children and now adults who had limited to no options," Dr. Wayne said.

In the Phase I component, between 3 and 12 patients will be treated, Dr. Wayne said. The small number treated is a safety requirement from the National Institutes of Health, which conducted a previous trial.

The new study uses a manufacturing process at Kite, and the NIH wants to be sure the new manufacturing process is safe. Assuming safety is demonstrated, the Phase II component will treat 50 patients. This comes as producing CAR-T is a tricky process, involving numerous procedures and intensive manufacturing processes for each patient, unlike more typical one-size-fits-all drugs.

A predecessor to the Children's Hospital trial in 2014 reported a complete response in 14 of 20 children or young adults with ALL treated with the therapy. Kite’s rival Juno Therapeutics also reported the results of its Phase II trial, with a similar cell therapy, back in March. 

The biotech’s prospect JCAR015 helped 27 of 29 adults with resistant ALL go into remission, promoting an additional wave of hype and speculation over CART.

A complete remission doesn't however mean the patients are cured, and they must be monitored to determine the treatment's long-term efficacy. The engineered T cells often, but not always, remain in the patients to attack the cancer if it returns.

The persistence of these cells has the side effect of killing normal immune cells called B cells that bear the CD-19 protein, Dr. Wayne said. This impairs the immune system. "Those individuals need to receive ongoing antibody replacement therapy to protect them from infections," he explained to the Tribune.

The FDA recently conferred its “breakthrough” tag to KTE-C19's for its trial programs in patients with refractory diffuse large B cell lymphoma, primary mediastinal B cell lymphoma, and transformed follicular lymphoma.

Kite last year launched a Phase I/II study in adults with ALL, and, in November, the company started a Phase II KTE-C19 study in mantle cell lymphoma.

Kite's plan is to execute on each trial over the coming months and gradually broaden the treatment's indication as more data roll in.

CART trial data has so far show impressive results in blood cancers, but its responses in solid tumors have bene less spectacular.  

Alongside Juno, Big Pharma players including Roche ($RHHBY), Pfizer ($PFE), ($GSK) and Novartis ($NVS), are all also researching in this space--with some also teaming up with biotechs to help advance their R&D.

Novartis recently published results of a study that saw its drug wipe out an aggressive blood cancer in 93% of children and young adults who received it--with 18 of 59 patients cancer-free after 12 months.

And back in late March, Kite signed a deal with Roche to test its new PD-L1 drug atezolizumab alongside KTE-C19 in patients with refractory, aggressive non-Hodgkin lymphoma.

Juno signed a similar deal last year to test a combination of one of its CARTs with AstraZeneca's ($AZN) PD-L1 blocker in NHL.

- see the San Diego Tribune’s take