2019 was actually quite a good year for initial public offerings (IPOs) even though there were 17% fewer than in 2018. Slightly over 60% of these newly minted stocks ended up trading above their issue price.

We hear a lot about successful IPOs, but what about the remaining 40% or so that went underwater in 2019? Here are snapshots of the 10 worst-performing issues of the year.

IPO spelled out in wooden blocks.

Image source: Getty Images.

1. Guardion Health Sciences

The steepest decline suffered in 2019 was by a small biotech, Guardion Health Sciences (NASDAQ:GHSI). Biotech stocks are notoriously volatile. And this one, which sells vision-testing devices and food engineered for better ocular health, has been deeply in the red lately. A sharp increase in stock-based compensation isn't helping, although a 33% year-over-year sales increase in the core medical-foods segment is promising.

Investors clearly aren't convinced, though. As of Dec. 27, Guardion's stock was trading a scary 94% below its IPO price. 

2. Greenlane Holdings

One of the biggest health scares of 2019 was the vaping crisis, which understandably knocked down stocks associated with it. Greenlane Holdings (GNLN -4.80%), a tobacco and cannabis accessories maker, was a big victim of this -- even though most of its product lineup isn't connected to vaping.

We should never underestimate the power of guilt by association. This, plus a string of bottom-line losses and sluggish year-over-year growth in Q3, has driven Greenlane's stock down by 82% from its issue price.

3. Axcella Health

Biotechs are frequently considered speculative investments because many of them are entirely in the development stage. That seems to be true of Axcella Health (NASDAQ:AXLA), which made its market debut in 2019. The company's pipeline consists of drugs that treat metabolic disorders, and so far it hasn't made any revenue. Meanwhile, its quarterly operating expenses last clocked in at over $14 million.

It seems that investors don't believe that the metabolic afflictions targeted by Axcella can be big money-spinners in the biotech world. Perhaps that's why the stock is down almost 82% since its IPO.

4. Super League Gaming

Esports (professional video gaming) have really taken off these past few years. Companies have crowded into this market, so scrappy operator Super League Gaming (NASDAQ:SLGG) is going after the amateur market, betting that audiences and sponsors will be willing to see less-developed talents pulverizing the pixels.

That's an interesting niche with potential, but Super League Gaming's operating expenses ballooned by $1 million year over year in its latest reported quarter, against a revenue increase of less than $200,000 or so. Investors are likely concerned that this dynamic won't reverse in the near future.

Super League Gaming's stock has not been a superperformer, sinking 79% below its IPO price.

5. Sundial Growers

One class of equities that got absolutely hammered in 2019 were marijuana stocks. A recent arrival on the scene, cannabis producer Sundial Growers (SNDL 2.19%), compounds this disadvantage by being a relatively low-margin wholesaler for the most part, rather than a value-added retailer.

Adding to the downbeat sentiment is Sundial's allegedly insufficient disclosure that a client returned 554 kilos of product due to impurities. This understandably led to a set of investor lawsuits. Sundial wilted even more than some of its downtrodden marijuana stock peers, falling by 77% from the price of its August IPO.

U.S. currency burning.

Image source: Getty Images

6. Stealth BioTherapeutics

Another early stage biotech, Stealth BioTherapeutics (MITO), made this list for 2019. Companies like Stealth are highly dependent on clinical trials of their pipeline drugs. Late in December, the company announced that its promising drug candidate elamipretide -- aimed at treating a muscular disorder called mitochondrial myopathy -- had not met its primary endpoints in a late-stage clinical trial.

Worse, Stealth had previously reached a $30 million deal with Alexion Pharmaceuticals for the latter to license elamipretide, pending the results of such testing. So that deal is almost certainly going up in smoke. The stock took a real hit on the news, and it hasn't recovered -- shares are off by 72% from their issue price. 

7. Wanda Sports Group

The IPO of China's Wanda Sports Group (NASDAQ:WSG) didn't start out auspiciously. The company, which has a somewhat eclectic set of sports media assets such as the Ironman triathlon and broadcast rights in Asia for soccer's World Cup, aimed to raise at least $252 million from its issue. Instead, it drew around $190 million.

There were several likely reasons for this, as well as for the subsequent poor performance of its American depositary shares (ADS). The preceding U.S. IPO of a Chinese company, esports specialist Douyu International Holdings, failed to excite the market. Also, Wanda Sports Group's owner, Dalian Wanda, was in the midst of shedding assets due to government pressure over foreign investments by Chinese companies.

So perhaps investors feel that Wanda's U.S. flotation was done more out of necessity (or even desperation) than anything else. Whatever the reason or reasons, the shares now trade at 67% under their IPO price.

8. YayYo

YayYo (NASDAQ:YAYO) is a rather oddly named company that aims to be a pick-and-shovel play on the ridesharing industry. It operates a fleet of cars for use by ride-hailing drivers without their own vehicles. It's also developed an agnostic booking platform for people seeking the cheapest or most advantageous ride available.

That's an interesting approach to the rideshare industry, which has grown massively but is also producing massive losses. Like the banner names in the sector, Uber Technologies and Lyft (both underperforming 2019 IPOs in their own right), YayYo is losing money. The company is also burning through its cash rapidly.

If investors are frosty on Uber and Lyft, you can bet they're not getting excited about YayYo. The stock is trading 66% below its IPO price. For comparison's sake, that figure is 34% for Uber, and almost 40% for Lyft.

9. Kaleido Biosciences

Helping to bring up the rear of our list is Kaleido Biosciences (KLDO), yet another biotech. This one aims to capitalize on the apparent health benefits of treating and manipulating the human gut microbiome (i.e., the microbes living in our digestive system).

This is a relatively new area of scientific inquiry. So basically, Kaleido is operating in a speculative sector to begin with (biotech), following a highly speculative path to success with the gut microbiome. Because of this, the company doesn't yet have revenue, while its operating expenses are deepening significantly. 

There don't seem to be many believers in the potential of the human gut microbiome to produce any kind of profit anytime soon (or even revenue, come to think of it), so Kaleido's shares are down 65% from their issue price.

10. Sonim Technologies

Any of us who have ever dropped an expensive electronic device can understand the appeal of a phone or tablet packed in a rugged, highly shock-resistant housing. Sonim Technologies (NASDAQ:SONM) specializes in this equipment and related services.

Unfortunately, there is weak demand from the wireless carriers that Sonim depends on to help move its wares. In September, the company alerted investors that because of this, its full-year revenue growth and net loss would be considerably worse than it indicated in its previous guidance. On top of that, both the CEO and CFO of the company recently departed.  

All of this makes a tough pill to swallow for investors, who collectively have driven Sonim's shares nearly 65% below their issue price.