What happened

After reporting data from a phase 1/2 clinical trial, shares of ProQR Therapeutics N.V. (PRQR 6.99%), a clinical-stage biotech focused on RNA medicines that treat rare genetic diseases, rose 70% as of 12:13 p.m. EDT on Wednesday.

So what

ProQR reported results from its phase 1/2 trial that is testing its compound called QR-110 as a hopeful treatment for LCA10, which is a genetic mutation that usually leads to childhood blindness.

Doctors giving thumbs up

Image source: Getty Images.

Here are the key takeaways from the study:

  • Use of QR-110 led to improvements in vision of the majority of patients when measured using visual acuity and the mobility course performance tests. Specifically, about 60% of patients showed a clinically meaningful response to the drug after three months of treatment. A secondary study also showed that the efficacy effects of the drug persisted beyond three months. 
  • The drug was well-tolerated by study participants, and no serious adverse events were reported.
  • A pivotal phase 2/3 trial is set to start in the first half of 2019.

Commenting on the study results, Dr. David Rodman, an executive vice president of R&D at ProQR, stated:

We observed a clinically meaningful improvement in vision in the treated eye as measured by both mechanistic and potential registration endpoints. Consistent with predictions based on our patient derived optic-cup models, improvement in visual function was observed as early as two months after treatment and was maximal and stable by three months and thereafter. 

Given the news, it isn't hard to figure out why shareholders are having a great day.

Now what

Today's update should provide investors with increased confidence that QR-110 might be the real deal. However, it's also important to remember that great phase 1/2 clinical news doesn't always repeat itself in larger late-stage trials. Given the risk, I'm content to root for ProQR's success from the safety of the sidelines.