What happened

Shares of Adverum Biotechnologies (NASDAQ:ADVM), a clinical-stage gene therapy company, jumped today in response to some compelling clinical trial results. Positive interim data from a study with the company's lead candidate, ADVM-022, has lifted the stock 12.2% as of 12:34 p.m. EDT on Wednesday.

So what 

Adverum has been treating patients who require frequent anti-VEGF injections to slow the progression of wet age-related macular degeneration (AMD) with different sized doses of its lead candidate ADVM-022. A single injection of ADVM-022 at the lowest dose tested helped four out of six patients go for a median of 36 weeks without requiring rescue injections. The same dose helped four out of five patients with a 20-week followup avoid rescue injections. 

Cash money raining down on a smiling investor.

Image source: Getty Images.

Among six patients treated with a higher dosage, none have required anti-VEGF rescue injections 60 weeks after a single injection of Adverum's gene therapy candidate.

Now what

At the moment, Eylea from Regeneron (NASDAQ:REGN) is the top-selling anti-VEGF injection and it's on pace to generate $7.4 billion in sales this year. Government payers tired of paying for regular Eylea injections could make ADVM-022 a go-to solution for growing numbers of older adults losing their vision to AMD and related disorders. 

As a once-and-done injection, Adverum needs to set a hefty price for ADVM-022 and it's going to take more than 60-week data to convince payers to take a chance on a longer-term solution. Adverum's AMD candidate could turn a multi-billion market for anti-VEGF drugs on its head if it continues to impress, but there's still a long road ahead.