Adaptimmune touts a promising snapshot of TCRs for myeloma

T-cell pioneer Carl June

Adaptimmune ($ADAP) posted a promising early glimpse of its potential in the TCR cancer drug arena, an up-and-coming arm of the engineered T-cell programs now in the clinic.

Investigators are reporting that out of 20 patients with advanced multiple myeloma, 14 responded with a near complete or complete response, with another two "very good" partial responders in the mix. That 80% rate of response compares very well with expected outcomes for all myeloma patients, according to the biotech.

Closely related and possibly superior to CAR-Ts (because they can go after intracellular as well as surface targets), Adaptimmune's lead TCR equips T cells extracted from patients to hunt down the NY-ESO-1 cancer testis antigen. This first batch of patients has now been studied for some time, allowing investigators to report evidence of prolonged durability--a key feature for the new treatments that are being pushed along in human studies. 

Of the 15 patients that underwent a marrow biopsy at day 100, 14 had engineered cells in their systems and there was clear evidence that the cells had migrated to tumors. The positive responses also came without any instances of cytokine storms, which have proven to be a lethal threat in CAR-T treatments.

Adaptimmune pulled off an upsized IPO that delivered $191 million earlier this year, giving the Oxford-based biotech another big leg up in its dramatic rise over the past year as GlaxoSmithKline ($GSK) lined up for a major collaboration deal. CAR-T leaders like Juno Therapeutics ($JUNO) and Kite ($KITE) have also been adding TCRs to their pipelines, looking to expand their work into multiple cancers. 

But investors weren't in a giving mood on Monday. The biotech saw its shares drop 7% Monday afternoon.

"This is the first report of TCR engineered T-cell therapy that has shown durable persistence in patients," said Penn's Dr. Carl June, one of the pioneers in the field of engineered T cells. "These data are encouraging for the TCR platform, which I believe will be an important technology due to its ability to target intracellular antigens."

"We believe these are significant data for Adaptimmune and for the cancer gene therapy field," commented Dr. Rafael Amado, Adaptimmune's chief medical officer (and former GSK exec). "The trial showed that autologous transduced cells can be safely administered to patients with advanced myeloma in the context of stem cell transplantation, and that the transduced cells persist for a prolonged period of time. There was also encouraging evidence of antitumor effect which supports further investigation of cell and gene therapy in myeloma."

- here's the release (PDF)