The Synairgen share price slumps! Here’s what I’d do now

The Synairgen share price has slumped following the publication of its latest trial results. This Fool isn’t planning to buy the decline.

| More on:

The content of this article was relevant at the time of publishing. Circumstances change continuously and caution should therefore be exercised when relying upon any content contained within this article.

You’re reading a free article with opinions that may differ from The Motley Fool’s Premium Investing Services. Become a Motley Fool member today to get instant access to our top analyst recommendations, in-depth research, investing resources, and more. Learn More.

The Synairgen (LSE: SNG) share price has crumbled in value in early deals this morning. The stock is off nearly 8%, at the time of writing. 

To put this decline into perspective, over the past 12 months, shareholders have seen a return of 126%. Moreover, since the beginning of 2020, the stock has risen by more than 2,000%. 

However, past performance should never be used as a guide to future potential. Just because the Synairgen share price has produced considerable returns in the past doesn’t mean it’ll continue to outperform. 

That has become painfully clear today after the firm published results from its phase II trial of inhaled interferon beta in Covid-19 patients.

Positive results 

Today’s update from the business was a positive one. According to Richard Marsden, CEO of Synairgen, the trial findings show that the “SNG001 treatment led to a threefold likelihood of recovery to ‘no limitation of activities’ in the markedly/severely breathless population compared to those on placebo in the home and hospital setting.

SNG001 is Synairgen’s formulation containing interferon beta for nebulisation. This allows delivery directly into patients’ lungs.

Some studies have shown that Covid-19 suppresses the natural production of interferon beta. The virus can also prevent the induction of antiviral responses by infected cells. Synairgen’s work appears to show that its SNG001 formulation containing interferon beta can help overcome this problem. 

However, the company is still a long way from commercialising the product. The latest findings still need to be peer-reviewed. It’s also in the process of completing a phase III trial. After that, regulators will need to approve the product.

Considering the volume of work still required, there’s no guarantee this product will ever successfully make it to market. I think that’s the most significant risk overhanging the Synairgen share price right now. 

Synairgen share price decline 

It’s difficult to tell exactly why the Synairgen share price has declined so substantially today. However, it looks to me as if the market is starting to become concerned about the firm’s valuation. 

The company’s current market capitalisation stands at £308m, which seems to me to be a lot, considering the success of SNG001 is far from guaranteed. 

Of course, on the other hand, if the treatment successfully makes it through the next trial stage and is approved by medical regulators, the market could be substantial. In this best-case scenario, the Synairgen share price may be incredibly undervalued at current levels.

Despite this, I’m not a buyer of the stock today. I think the company’s future is incredibly uncertain. Until we have more information on the SNG001 treatment, there’s no guarantee whatsoever this will ever be a sustainable business.

This is just my own personal preference as I don’t like to invest in companies still in the development stage. However, other investors may be comfortable taking on this level of risk. 

Rupert Hargreaves has no position in any of the shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.

More on Investing Articles

Yellow number one sitting on blue background
Investing Articles

I asked ChatGPT to pick 1 growth stock to put 100% of my money into, and it chose…

Betting everything on a single growth stock carries massive danger, but in this thought experiment, ChatGPT endorsed a FTSE 250…

Read more »

Portrait of pensive bearded senior looking on screen of laptop sitting at table with coffee cup.
Investing Articles

How little is £1,000 invested in Diageo shares at the start of 2025 worth now?

Paul Summers takes a closer look at just how bad 2025 has been for holders of Diageo's shares. Will things…

Read more »

Aston Martin DBX - rear pic of trunk
Investing Articles

After a terrible 2025, can the Aston Martin share price bounce back?

The Aston Martin share price has shed 41% of its value in 2025. Could the coming year offer any glimmer…

Read more »

Close-up of British bank notes
Investing Articles

How much do you need in an ISA to target £3,000 per month in passive income?

Ever thought of using an ISA to try and build monthly passive income streams in four figures? Christopher Ruane explains…

Read more »

piggy bank, searching with binoculars
Investing Articles

Want to aim for a million with a spare £500 per month? Here’s how!

Have you ever wondered whether it is possible for a stock market novice to aim for a million? Our writer…

Read more »

Investing Articles

Want to start buying shares next week with £200 or £300? Here’s how!

Ever thought of becoming a stock market investor? Christopher Ruane explains how someone could start buying shares even on a…

Read more »

Rear view image depicting a senior man in his 70s sitting on a bench leading down to the iconic Seven Sisters cliffs on the coastline of East Sussex, UK. The man is wearing casual clothing - blue denim jeans, a red checked shirt, navy blue gilet. The man is having a rest from hiking and his hiking pole is leaning up against the bench.
Investing Articles

2 ideas for a SIPP or ISA in 2026

Looking for stocks for an ISA or SIPP portfolio? Our writer thinks a FTSE 100 defence giant and fallen pharma…

Read more »

Midnight is celebrated along the River Thames in London with a spectacular and colourful firework display.
Investing Articles

Could buying this stock at $13 be like investing in Tesla in 2011?

Tesla stock went on to make early investors a literal fortune. Our writer sees some interesting similarities with this eVTOL…

Read more »