How high can stocks go? The answer: It depends on the stock. With valuations at record highs, there's a good case to be made that many stocks don't have much more room to run.

However, there are some notable exceptions if analysts' views are right. Here are three stocks that Wall Street thinks will skyrocket 50% or more.

Three lines with arrows and dollar signs on them trending up.

Image source: Getty Images.

Ionis Pharmaceuticals

Ionis Pharmaceuticals (IONS -1.53%) has been a big loser so far this year with shares sinking 34%. However, Wall Street analysts seem to believe the biotech stock can make an impressive comeback. The average price target for Ionis reflects a 56% premium above the current share price.

The main reason behind Ionis' dismal year-to-date performance was Roche's disappointing results from a late-stage study evaluating tominersen in treating Huntington's disease, a rare genetic disorder. Roche licensed the experimental therapy from Ionis in 2017. 

Most analysts appear to remain bullish about Ionis, though. That's likely because of the company's robust pipeline. Ionis has nearly 50 programs in clinical testing, including seven in late-stage studies.

The company expects several key data readouts in the second half of 2021. Perhaps the most important of these is Biogen's anticipated results from a late-stage study of tofersen in treating neurodegenerative disorder amyotrophic lateral sclerosis (ALS). 

Quidel

Quidel (QDEL) is another stock that has tumbled quite a bit in 2021. After jumping more than 40% by early February, shares of the diagnostic testing company have plunged 56% below the peak level.

The bad news for Quidel is good news for Americans. COVID-19 testing volume has declined significantly with fewer suspected cases of the disease. That's due in large part to the increased availability of vaccines.

Wall Street analysts still like Quidel's prospects, though. The consensus price target for the stock is 52% above the current share price.

What's behind this rosy outlook? It could be that analysts expect a resurgence in COVID-19 testing in the fall and winter, especially with the emergence of new coronavirus variants. Quidel is also likely to benefit from a predicted nasty cold-and-flu season

Scotts Miracle-Gro

Scotts Miracle-Gro (SMG -1.11%) has taken investors on a rollercoaster ride so far this year. The stock has had four swings -- both up and down -- of at least 20%. Analysts appear to think the ride could be a fun one going forward: The average price target for Scotts reflects a 53% premium to its current share price.

The biggest growth driver for Scotts is its Hawthorne segment, which is a top supplier of hydroponics and gardening products to the cannabis industry. Hawthorne should have tremendous growth prospects as the legal cannabis markets in states that have recently legalized cannabis expand.

However, we can't overlook Scotts' core consumer lawn and garden business. Earlier this month, the company raised its guidance for fiscal year 2021 due mainly to the strength in its U.S. consumer segment. 

It's likely that Wall Street views Scotts Miracle-Gro as one of only a handful of stocks that give less aggressive investors a way to profit from the cannabis boom. Scotts even offers a dividend, something that very few pot stocks do.