What happened

Shares of the anti-cancer cell therapy company Adaptimmune Therapeutics (ADAP -5.26%) are having an unusually strong showing today. Specifically, the biotech's stock is up by a whopping 26.8% on sky-high volume as of 2:17 p.m. ET on Tuesday.

What's fueling this double-digit rally? Ahead of the opening bell, Adaptimmune released both its third-quarter earnings and a clinical program update for its MAGE-A4 franchise. However, the real needle-moving event from today's early morning news releases appears to be Adaptimmune's decision to  move forward with its genetically engineered T-cell therapy for advanced ovarian cancer. 

So what

In an exploratory study of patients with various solid tumors, the company's modified T-cell therapy, known as ADP-A2M4CD8, reportedly produced an overall response rate of 43% in patients with advanced ovarian cancer. As a result, Adaptimmune said that it will advance the therapy into a phase 2 trial for this indication as both a monotherapy and in combination with a checkpoint inhibitor. 

What's the big deal? Even though there are scores of approved therapies for this particular malignancy, novel disease-modifying products such as this cell therapy should still be able to generate a sizable sum in annual sales. Adaptimmune, in turn, might finally have a viable blockbuster candidate under development. 

Now what

Adaptimmune's shares have been under enormous pressure all year long. Investors have moved to the sidelines on this healthcare stock over concerns about the prospects of modified T-cell therapies in the solid tumor setting in general, the company's long-term financial requirements, and the modest commercial prospects of its lead clinical indication (synovial sarcoma). These latest clinical data, however, ought to assuage at least some of these concerns moving forward.