So here’s an example of just how inefficient the smaller end of the biotech sector can be. Fortress Biotech Inc (NASDAQ:FBIO) spiked more than 50% after the market closed on Wednesday, as the company put out a release detailing some upcoming data published in an industry journal. It’s great news, but it’s not new. The company reported the same data back at the end of November in a press release, meaning the only development (and the driver behind the gain) is the suggestion that the data is being published in a journal. It’s good news, of course, but it looks as though markets are moving on the implications of the data itself, not the journal.

Regardless, it’s running up, so it’s worth taking a look at the underlying data to see if the 50% revaluation is justified. Here goes.

The drug is called MB-101, and it’s a form of oncology immunotherapy. Right now, it’s targeting a lead indication of glioblastoma (GBM), but it’s theoretically applicable to a pretty wide range of solid tumors. As a quick side note, it’s actually being developed by an entity called Mustang Bio, Inc., which is a wholly owned sub of Fortress. MB-101 is a CAR-T cell therapy, which has been engineered to express a receptor called IL13Rα2. For those not familiar with way this sort of treatment works, physicians take T cells from a patient and then engineer them to express a particular receptor. They then upscale the engineered T cell so there’s lots of them (millions) and introduce them back into the body. The receptor that the cells have been engineered to express are the same as those expressed by the cancer that the treatment is targeting, so when the immune system recognizes the receptor expressed by the CAR-T cells, it is subsequently trained to recognize the same receptors on the cancer cells.

The trick in optimizing this treatment is trying to find a receptor that the cancerous cells express in abundance, but that healthy cells don’t express at all, or to a very low degree. The bigger the gap between the healthy cell expression and the cancer cell expression, the more selective the treatment, and the lower the impact on non cancerous cells (read: the lower the side effects of the therapy). MB-101 targets the IL13Rα2 receptor, and not the IL13Rα1 receptor. GBM cells express a large amount of the former, and not the latter, while healthy cells express the opposite. This suggests, then, that it should be very highly selective to the cancer cells, and leave the healthy cells alone.

So what’s the run based on?

Back at the end of November, Fortress put out a press release detailing the results from a phase I study in seven patients. Five of the seven demonstrated anti tumor activity, and one (who was the only patient to receive the drug via a dual delivery system incorporating both intracavitary and intraventricular administration) demonstrated a complete response for 7.5 months. It’s this latter patient that is going to be the subject of the journalized report, and the journal in question is the New England Journal of Medicine.

Is it that big a deal?

There are two ways to look at this. The first, the positive way, that it’s an amazing result. This is an incredibly deadly brain cancer, and 7.5 months’ complete response is unheard of. That the patient was the only on to receive the above mentioned administration method makes it even more interesting, as this presents Fortress (Mustang) with a focal point in the forward trials.

The second, the not so positive way, is that it’s just one patient, and to pick up a 50% gain in market capitalization on the back of one patient in a phase I study seems a little optimistic.

What’s more important than this latest move, is what comes next. We want to see Mustang follow up with some phase II data investigating the combination delivery method, so as we can see whether this was a determining factor in the great efficacy readout, or whether it was just anomalous. If it can show the former to be true, that’s when we’ll see some serious upside.