Just because a business does not make any money, does not mean that the stock will go down. For example, biotech and mining exploration companies often lose money for years before finding success with a new treatment or mineral discovery. Nonetheless, only a fool would ignore the risk that a loss making company burns through its cash too quickly.

So should Prothena (NASDAQ:PRTA) shareholders be worried about its cash burn? For the purpose of this article, we'll define cash burn as the amount of cash the company is spending each year to fund its growth (also called its negative free cash flow). First, we'll determine its cash runway by comparing its cash burn with its cash reserves.

Does Prothena Have A Long Cash Runway?

You can calculate a company's cash runway by dividing the amount of cash it has by the rate at which it is spending that cash. As at September 2024, Prothena had cash of US$519m and no debt. In the last year, its cash burn was US$155m. That means it had a cash runway of about 3.3 years as of September 2024. Notably, analysts forecast that Prothena will break even (at a free cash flow level) in about 4 years. So there's a very good chance it won't need more cash, when you consider the burn rate will be reducing in that period. The image below shows how its cash balance has been changing over the last few years.

How Well Is Prothena Growing?

Prothena boosted investment sharply in the last year, with cash burn ramping by 74%. As if that's not bad enough, the operating revenue also dropped by 5.4%, making us very wary indeed. Considering both these metrics, we're a little concerned about how the company is developing. While the past is always worth studying, it is the future that matters most of all. So you might want to take a peek at how much the company is expected to grow in the next few years.

How Hard Would It Be For Prothena To Raise More Cash For Growth?

Prothena seems to be in a fairly good position, in terms of cash burn, but we still think it's worthwhile considering how easily it could raise more money if it wanted to. Companies can raise capital through either debt or equity. Commonly, a business will sell new shares in itself to raise cash and drive growth. By comparing a company's annual cash burn to its total market capitalisation, we can estimate roughly how many shares it would have to issue in order to run the company for another year (at the same burn rate).

Prothena has a market capitalisation of US$741m and burnt through US$155m last year, which is 21% of the company's market value. That's fairly notable cash burn, so if the company had to sell shares to cover the cost of another year's operations, shareholders would suffer some costly dilution.

Is Prothena's Cash Burn A Worry?

On this analysis of Prothena's cash burn, we think its cash runway was reassuring, while its increasing cash burn has us a bit worried. One real positive is that analysts are forecasting that the company will reach breakeven. Cash burning companies are always on the riskier side of things, but after considering all of the factors discussed in this short piece, we're not too worried about its rate of cash burn. Readers need to have a sound understanding of business risks before investing in a stock, and we've spotted 2 warning signs for Prothena that potential shareholders should take into account before putting money into a stock.

Of course, you might find a fantastic investment by looking elsewhere. So take a peek at this free list of interesting companies, and this list of stocks growth stocks (according to analyst forecasts)

Have feedback on this article? Concerned about the content? Get in touch with us directly. Alternatively, email editorial-team (at) simplywallst.com.
This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.