What happened

Shares of the gene-editing upstart CRISPR Therapeutics AG (CRSP 1.08%) rose by a market-beating 13.4% in April, according to data from S&P Global Market Intelligence. The biotech's stock perked up after the company announced that the Food and Drug Administration (FDA) granted fast track designation for CTX001 for the treatment of transfusion-dependent beta thalassemia (TDT).

CRISPR is codeveloping CTX001 with Vertex Pharmaceuticals (VRTX 0.10%) as a treatment for both TDT and sickle cell disease. The pair became the first in history to initiate a company-sponsored human trial for a CRISPR-based product when CTX001's early stage trial for TDT kicked off last February.

A cell floating in blood with strands of DNA nearby.

Image Source: Getty Images.

So what

Fast track status permits a drug developer more frequent interactions with the FDA and may open the door to an accelerated review, depending on the data. So this regulatory win is a step in the right direction for CRISPR and Vertex.

That said, there are plenty of experimental drugs and therapies that receive this regulatory designation that either end up going nowhere in clinical studies or get rejected by the agency during their initial review. As a result, CRISPR's double-digit move on this regulatory news probably wasn't altogether warranted. Fast track is a nice win for the company, but all that really matters in this case is the data.

Now what

Fortunately, investors shouldn't have to wait all that long to know whether or not CTX001 is a viable therapy. The lowdown is that TDT requires blood transfusions every few weeks to be effectively managed. As such, a slowdown in the rate of transfusions in CTX001-treated patients should be evident fairly quickly -- perhaps within a matter of months. The therapy's side effect profile will undoubtedly take longer to properly characterize, but CTX001's efficacy shouldn't remain a mystery much longer.