Kite Pharma has once again demonstrated just how hot experimental CAR-T technology is in the cancer field. The Santa Monica, CA-based biotech reported Monday evening in a trial update that 12 of 13 evaluable patients with advanced B cell malignancies demonstrated a complete or partial response after being treated with its chimeric antigen receptor (CAR) T cell therapy.
The latest news of the responses from the Phase I/IIa study run out of the National Cancer Institute–a slightly revised and improved update to the data already discussed–sent its shares ($KITE) shooting up more than 40% in after-market trading. But the stock quickly settled back down to about a 17% gain by Tuesday morning as investors absorbed the latest numbers in context with its past releases.
Kite’s lead drug is KTE-C19, which uses T cells extracted from the patients, genetically modifies them to express a chimeric antigen receptor for the CD19 protein, and then releases them to track down the cancer cells that express CD19 on their surface. Eight of the 12 cancer patients with B cell lymphomas and leukemias had a complete response, with no telltale sign of the cancer remaining, while four others had a partial response. And of seven evaluable patients in the same cohort with chemotherapy-refractory diffuse large B-cell lymphoma (DLBCL), four achieved complete remission, “three of which are ongoing with durations ranging from 9 to 22 months.” There were also two partial remissions.
The data will be familiar to longtime Kite observers who read through the biotech’s May S-1 filing for its IPO. At the time, the biotech relied on an 84% response rate from the ongoing study to help drum up strong support for the offering, which raised $140 million. These latest results, with a 92% response rate, are somewhat better. But there were also severe side effects involved in this study.
“As seen in other studies,” Kite noted, “infusion of anti-CD19 CAR T cells was associated with significant, acute toxicities, including fever, low blood pressure, focal neurological deficits, and delirium.” Earlier this year, rival Juno Therapeutics was forced to stop dosing non-Hodgkin lymphoma patients temporarily to adjust for incidents of cytokine release syndrome. Two patients died from the resulting fever, forcing investigators to tailor their recruitment practices.
One of the remarkable aspects of these treatments is their ability to alter the course of disease for some very sick patients, a factor that may well help speed the development effort. In the S-1, Kite noted that if another Phase I/II study planned for 2015 goes well, the company will file for an accelerated approval.
“To date, Kite and the NCI have conducted an extensive program to investigate personalized T cell immunotherapies for blood cancers and solid tumors, including in patients with refractory (hard to treat) DLBCL,” noted David Chang, the head of R&D at Kite, in a statement. “Both the high overall response rate and the durability of the complete remissions are noteworthy, and we believe our anti-CD19-CAR T cell approach holds great potential for the treatment of B cell malignancies, including those with aggressive, resistant disease for which there are no viable treatment options.”
CAR-T programs have been springing up in several biotechs in recent months. Just days ago, one of the leaders in the field, Seattle-based Juno Therapeutics, added $176 million to its massive war chest for CAR-T development work. Novartis ($NVS), meanwhile, is bankrolling a rival group that spun out of the University of Pennsylvania, which inspired CEO Joe Jimenez to promise a blank check to fund an accelerated R&D program. Other companies involved in the field include Celgene ($CELG) and its partner bluebird bio ($BLUE) as well as Pfizer ($PFE) and Cellectis.
“Based on this substantial progress, Kite plans to file an IND in the fourth quarter of this year to initiate a Phase I/II single-arm multicenter clinical trial of KTE-C19 in patients with DLBCL who have failed two or more lines of therapy,” said Kite CEO Arie Belldegrun. “We are excited to advance this promising therapy and anticipate commencing patient enrollment in our DLBCL clinical trial in the first half of 2015.”
Barbara Jacoby is an award winning blogger that has contributed her writings to multiple online publications that have touched readers worldwide.