The shares of 27 AIM companies have doubled or better so far in 2018. For those that don't know, AIM is the Alternative Investment Market, the junior trading platform of the stock market designed to nurture small, growth companies.

While the rewards can be substantial, so are the risks, a point illustrated by Bahamas Petroleum (BPC:AIM) today. Its stock tanked more than 60% on Friday 24 August after an unnamed oil major partner walked away from a licence deal, as we explain in more depth here.

Before today's developments shares in Bahamas Petroleum had rocketed 694% during 2018. Yet even after Friday's steep sell-off the stock has still soared 181% year to date, although investors obviously need to reassess Bahamas Petroleum's billions of barrels of oil reserves are worth the company's current £35m market valuation.

Other standout AIM performers so far this year include Sopheon (SPE:AIM)Tern (TERN:AIM), Webis (WEB:AIM) and SkinBioTherapeutics (SBTX:AIM).

Sopheon, the research, development and lifecycle software designer - a previous Great Idea of Shares, has enjoyed a 180% share price rally to 990p having upgraded growth guidance several times.

COMPANIES THAT HAVE STRUGGLED

The nature of AIM's smaller company members typically ,means that for every successful share price performer, there are likely to be several flops.

Take drug discovery firm minnow ImmuPharma (IMM:AIM), for example. Its share price has crashed by nearly 90% during 2018 after its autoimmune disease Lupus treatment Lupuzor failed crucial Phase III clinical trials.

That news sparked an incredible 85% share price collapse on the day.

Biopharma business Faron Pharmaceuticals (FARN:AIM) struggled with a sell-off when its Phase III trial for its acute respiratory disease syndrome drug Traumakine failed in May.

Investors appear to have no faith in the company as the shares are down 86% so far this year.

Other small-caps with share price losses over 80% include Safestyle (SFE:AIM), Eve Sleep (EVE:AIM) and Magnolia Petroleum (MAGP:AIM).

Find out how to deal online from £1.50 in a SIPP, ISA or Dealing account.

Issue Date: 24 Aug 2018