We have some exciting news to share! The Motley Fool UK has now become The Twelfth Magpie -- an independent, UK-owned company, led by our long-serving UK management team — Mark Rogers, Chris Nials and Heather Adlington. In practical terms, it’s the same team you know, now fully focused on serving our UK readers and members.

Just as importantly, our approach remains unchanged: long-term, jargon-free, and on your side. This site is our new home, and there will be extra tweaks made across the coming few days as we settle in. So if anything looks a little off, please bear with us!

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.

The Synairgen share price has rocketed 500% in two days! Here’s what I’d do now

The Synairgen share price (LON:SNG) has had a storming two days following positive results on a potential treatment for coronavirus. Should new investors go all-in?

| More on:

You’re reading a free article with opinions that may differ from The Twelfth Magpie’s Premium Investing Services. Become a member today to get instant access to our top analyst recommendations, in-depth research, investing resources, and more. Learn more, and get a free 'Best Buy Now' stock!.

Yesterday, respiratory drug developer Synairgen (LSE: SNG) jumped an astonishing 420% in value. It’s up another 15% this morning. Could there be even more to come? Quite possibly. That said, I think anyone investing should keep their expectations in check.

Before explaining why, let’s have a recap.

Should you buy Synairgen Plc shares today?

Before you decide, please take a moment to review this report first. Despite ongoing uncertainties from US tariffs to global conflicts, Mark Rogers and his team believe many UK shares still trade at substantial discounts, offering savvy investors plenty of potential opportunities to learn about.

That’s why this could be an ideal time to secure this valuable research – Mark’s analysts have scoured the markets to reveal 5 of his favourite long-term ‘Buys’. Please, don’t make any big decisions before seeing them.

What’s behind Synairgen’s rise?

Monday’s share price jump followed news of a successful trial of a treatment. labelled SNG001 (an inhaled dosage of interferon beta), in patients who had been hospitalised as a result of coronavirus.

Results showed those who received the drug in a double-blind trial (where neither the patient nor the clinician knows who is getting what) had a 79% lower risk of severe disease compared to those who received the placebo. Those on SNG001 were also more than twice as likely to recover than those who didn’t receive the drug.  

With concerns that the arrival of winter could bring about a fresh wave of the coronavirus, news that the treatment helps the lungs to tackle the virus, even in the event of co-infection (e.g. if a person catches flu), is clearly very positive. 

Can the share price keep rising?

Here, from an investment point of view, is where things get tricky.

What’s important to remember — and the company clarified today — is that the recent positive outcome was a Phase 2 trial. This phase is “designed to test the efficacy of a drug and takes place before the drug is approved or able to be marketed.” In other words, a lot of questions still need answering.

While positive that patients in both groups were matched with each other in things like age, this trial involved just 101 patients — a very small sample. Also, all were recruited in the UK, which means results might not be generalisable to other countries.

Nor did every finding from the trial reach statistical significance. In other words, we can’t be absolutely sure that what was found wasn’t just down to luck. Naturally, all this makes a much larger trial of the treatment (Phase 3 of drug development) absolutely essential. 

In short, I think SNG001 is still far from the sure thing the market presumably now believes it to be. For me, this has implications for what the Synairgen share price will do next.

The problem is that not everyone will want to stick around for the ride. It will, after all, be a few weeks before the company is ready to reveal the outcome of further analyses. If I were a trader and knew this, I’d seriously consider banking some profit on Synairgen.

And if I were a Foolish investor buying stocks for the long term (and I am), I’d be sure to appreciate that some in the market work on much shorter timescales and act (or not act) accordingly.

Buyer beware

Synairgen could certainly still reward those buying in now. However, I would caution anyone against thinking they can make easy money in a set period of time. It’s very easy to find examples of promising treatments that failed to live up to the initial hype and progress beyond Phase 3.

We must not allow our desire for a quick profit to override our true tolerance for risk. If you’re going to expect anything from the share price, expect volatility. Don’t bet the ranch and ensure you’re diversified elsewhere.

Paul Summers 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

House models and one with REIT - standing for real estate investment trust - written on it.
Investing Articles

How investing £4.50 a day could set you on the way to a £1,505 monthly second income

How can UK stocks with high dividend yields help investors earn a meaningful second income from the price of a…

Read more »

Investing Articles

Up 103% with a P/E of 261 — is this FTSE 100 stock still worth buying?

One FTSE 100 stock is quietly moving higher while most investors are still looking elsewhere — is the market missing…

Read more »

Concept of two young professional men looking at a screen in a technological data centre
Investing Articles

The smart money thinks AI stocks look risky — but is there still a chance to buy?

According to fund managers, the AI trade is getting crowded. But they still seem to think it’s the place to…

Read more »

Man putting his card into an ATM machine while his son sits in a stroller beside him.
Investing Articles

Barclays shares are 11% below their 52-week high. Could they be a bit of a bargain to consider?

Overpriced or one of the FTSE 100’s hidden gems? James Beard takes a closer look at how the market is…

Read more »

Stack of one pound coins falling over
Investing Articles

Down 65% but yielding 6.7% – is this beaten-down UK stock now a generational bargain?

Harvey Jones says this UK stock is one of the worst FTSE 100 performers but there are sound reasons to…

Read more »

Portrait of elderly man wearing white denim shirt and glasses looking up with hand on chin. Thoughtful senior entrepreneur, studio shot against grey background.
Investing Articles

Is this FTSE stock really 46% undervalued?

Analysts reckon this FTSE stock should be worth nearly 50% more. James Beard considers why there’s so much positivity surrounding…

Read more »

Front view of a young couple walking down terraced Street in Whitley Bay in the north-east of England they are heading into the town centre and deciding which shops to go to they are also holding hands and carrying bags over their shoulders.
Investing Articles

How much is needed in an ISA for passive income that covers the UK’s monthly average rent of £1,381?

The UK’s monthly average rent for May 2026 is £1,381. Muhammad Cheema looks at how much is needed to aim…

Read more »

A rear view of a female in a bright yellow coat walking along the historic street known as The Shambles in York, UK which is a popular tourist destination in this Yorkshire city.
Investing Articles

How have BAE Systems shares become a dividend powerhouse? 5 reasons why!

Dividends on BAE Systems shares have risen every year without fail since the early 2000s. So what's the FTSE 100…

Read more »