What happened

Adverum Biotechnologies (ADVM -4.96%), a clinical-stage gene therapy company, is off to a particularly good start today. Specifically, the biotech's shares are up by a healthy 25%, on extremely heavy volume, as of 9:39 a.m. EDT Tuesday. 

Adverum's shares are blasting higher this morning in response to a positive clinical update for the company's experimental gene therapy candidate ADVM-022. Yesterday the company announced that the therapy was showing signs of robust efficacy and an acceptable safety profile in an early-stage dosing study in patients with wet age-related macular degeneration (wet AMD). 

A researcher in a lab coat pointing to an enlarged piece of DNA.

Image source: Getty Images.

So what

Adverum is essentially attempting to upend the $10 billion wet AMD drug market with ADVM-022. The basic idea is to supplant the current host of drugs -- such as Avastin, Lucentis, and Eylea -- with a one-and-done gene therapy. Based on the data so far, it seems ADVM-022 may in fact be able to achieve this lofty goal. What's more, the company even has a shot at growing the wet AMD market by leaps and bounds by increasing compliance among elderly patients. So this sizable move northward does have a solid rationale behind it.    

Now what

Is this red-hot biotech stock still a buy? While it could be a few more years before ADVM-022 is ready for its commercial debut, gene therapy companies have been exceedingly hot commodities on the merger-and-acquisition scene for a while now. So it wouldn't be surprising if one or more suitors emerged from the shadows in the wake of this impressive early-stage data. That being the case, risk-tolerant investors may want to grab a few shares of this top gene therapy play soon.