There's at least one thing that all huge biotechs share in common. Every one of them started out a lot smaller. A key reason why many people invest in biotech companies is that they expect them to grow much larger. And some of them can deliver especially impressive returns.

We asked three Motley Fool contributors to identify three explosive biotech stocks that could generate 10X returns within the next 10 years. Here's why they chose BioNTech (BNTX -2.58%), CRISPR Therapeutics (CRSP 8.90%), and Gritstone Bio (GRTS 6.40%).

Large gold and silver 3D objects that spell out "10X."

Image source: Getty Images.

The ultimate bet on coronavirus vaccines 

Zhiyuan Sun (BioNTech): In the past year, BioNTech shares have more than quintupled on investor enthusiasm surrounding its coronavirus vaccine, Comirnaty, developed jointly with Pfizer (PFE -1.24%). The company has gone from essentially a nobody to a biotech with a market cap topping $80 billion. What's more, the stock is still cheap after the rally, trading at a forward price-to-sales ratio of four and a forward price-to-earnings ratio of eight.

One big catalyst going forward for BioNTech is the company's partnership with China's Fosun Pharmaceutical. Under the agreement, BioNTech will receive 65% of gross profits for Comirnaty vaccine sales in China. In a rare display earlier in April, Chinese officials admitted that made-in-China vaccines from Sinopharm and Sinovac have low efficacy. So there's definitely a lot of potential for the commercialization of an effective one.

BioNTech and Pfizer have shipped over 1 billion doses of Comirnaty to more than 100 countries worldwide. But that's just the beginning. With the rise of mutations such as the delta variant, there are more breakthrough cases than ever.

Not only will booster shots likely be needed in countries including the U.S., but developed nations could also need to buy more vaccines to ship to countries that can't afford them. Otherwise, the coronavirus could keep spreading with the possibility of even more deadly mutations emerging.

Fortunately, a third dose of the Pfizer-BioNTech vaccine is sufficient to obtain a high level of protection against most variants. Thus, I'm confident that BioNTech can sustain its current level of growth going forward. In fact, the company has more than 2 billion vaccine orders this year and 1 billion more for the next. What's more, bear in mind that BioNTech is investing in a state-of-the-art oncology pipeline for the long term. It is therefore a top biotech stock to buy now. 

Betting on the future of gene-editing 

Prosper Junior Bakiny (CRISPR Therapeutics): Explosive growth often comes with significant breakthroughs. And for biotech investors, the field of gene editing shows real promise. The group of methods known as gene editing -- which allows scientists to modify an organism's DNA -- could lead to significant medical advances in the next decade and beyond. 

One company looking to make waves in this industry is CRISPR Therapeutics. The biotech is developing gene-editing therapies for several illnesses, some of which have a significant unmet need. The company's leading pipeline candidate is CTX001, a potential treatment for rare blood disorders transfusion-dependent beta-thalassemia (TDT) and sickle-cell disease.

There are few treatment options for both diseases. Receiving regular blood transfusions is one of them. But this method -- as well as other standard therapies for sickle-cell disease and TDT -- comes with significant risks. Meanwhile, CTX001 would be a one-time curative treatment for both illnesses, if approved. 

In a phase 1/2 study, 15 TDT patients treated with CTX001 were transfusion-independent within two months of treatment -- with a follow-up between four and 26 months. These patients needed anywhere from 20 to 61 transfusions per year prior to treatment. That's clearly a successful result, at least so far. 

CRISPR Therapeutics is developing CTX001 in collaboration with Vertex Pharmaceuticals, meaning the company will have to share the financial windfall from this program with the larger biotech, if it earns U.S. regulatory approval. But CTX001 is a wonderful proof of concept for the rest of CRISPR Therapeutics' pipeline.

The company is advancing a trio of programs in the field of immuno-oncology, one of the most lucrative subfields in the pharmaceutical industry. I fully expect CRISPR Therapeutics to earn significant regulatory nods within the next decade, and for biotechs, that's one of the keys to beating the market. 

CRISPR Therapeutics has been lagging behind the market lately. It's more than 20% below the all-time highs reached earlier this year. Don't miss the opportunity to scoop up shares of this promising biotech while they are down. 

A small pioneer on two big fronts  

Keith Speights (Gritstone Bio): What are the most important biopharmaceutical advances over the last decade or so? I'd put immunotherapies and messenger RNA (mRNA) vaccines high on the list. There's one small biotech that could be on course to make major advances in both of these areas -- Gritstone Bio.

The key for Gritstone to pull this off is its two-pronged scientific platform. The first component, Gritstone EDGE, uses artificial intelligence to pinpoint antigens in a tumor or virus that are most likely to be recognized and targeted by the body's immune system. The second component is the company's two-part prime-boost vaccine approach. It uses a virus to deliver the prime dose of a vaccine/immunotherapy and a self-amplifying mRNA boost. 

Gritstone's pipeline includes three candidates in clinical testing. Granite is a personalized cancer vaccine that's currently in phase 2 studies targeting several types of cancer. Slate is an off-the-shelf cancer vaccine in phase 2 testing targeting KRAS-mutant cancers. Coral is Gritstone's COVID-19 vaccine candidate that's in phase 1 testing. The biotech believes that Coral could offer stronger protection against emerging coronavirus variants than currently available vaccines. 

To be sure, Gritstone is a risky investment. There's no guarantee that its pipeline candidates will be successful. However, with its promising platform and a market cap below $600 million, I think that it could very well be a monster stock in the making.