A first look at a revolutionary new cancer therapy produced mixed results that impressed oncologists, but depressed shares of CRISPR Therapeutics (CRSP -0.88%) -- the company developing it. Treatment with the candidate, CTX110, led to complete remission for two out of the four patients who received the third-highest dose of the CAR-T therapy. Sadly, one patient who had been treated with the highest dosage died from apparently unrelated complications after treatment with CTX110 helped him to achieve complete remission.

The Carbon trial enrolled non-Hodgkin's lymphoma patients with disease that either had recurred or never responded to multiple lines of therapy. That any of these patients responded to CTX110 was remarkable, but investors were disappointed with the level of efficacy, which didn't seem competitive with existing treatments that take a similar approach.

Blood sample in a laboratory.

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For example, a single infusion of Yescarta from Gilead Sciences (GILD -0.74%) led to complete remission for 51 out of 101 non-Hodgkin lymphoma patients. At least one of the patients treated with CTX110 at the dosage selected for a larger pivotal study received more than one dose after the first failed to produce the desired effect.

It's dangerous to read too much into the interim results of studies involving so few patients, but oncologists will want to hear a lot more about CTX110 and the younger allogeneic CAR-T programs advancing through CRISPR Therapeutics' pipeline.

Yescarta and other similar treatments that CTX110 might end up competing with differ from it in a key way.

Those autologous therapies are made by harvesting a patient's own stem cells and re-engineering them to recognize and fight the individual's cancer. Then, those cells are infused back into the original patient. It's a long process that can take time someone with cancer may not have, which is one reason sales of autologous CAR-T therapies have been somewhat disappointing so far. By contrast, CTX110 is an allogeneic therapy -- the cells being used come from a compatible donor line, and the treatment could be available off the shelf.