Image source: Getty Images Moderna (NASDAQ: MRNA) stock is rising today after the biotech company reported positive results from one of its phase 3 clinical trials. As I type, the stock is up 8%. The firm said data from the trial for its mRNA-1345 vaccine candidate showed an efficacy of 83.7% against respiratory syncytial virus (RSV) in older adults. Based on these results, Moderna intends to submit the vaccine for regulatory approval with the US Food and Drug Administration (FDA) by mid-2023. Moderna, Pfizer, and GSK are now racing to get their RSV vaccines to market first. What is messenger RNA? Moderna uses messenger RNA (mRNA) to instruct the body’s cells to produce proteins that can prevent or fight diseases. In essence, its technology turns human cells into drug factories. We know this technology works in humans thanks to coronavirus. This was after new mRNA vaccines were given fast-track approval by regulators during the pandemic. Needless to say, the idea of programming the body like software is a revolutionary one. And an extremely disruptive one if it works beyond its current use for Covid. There is now growing evidence that it might. Personalised cancer vaccines Last month, Moderna reported that its personalised mRNA cancer vaccine was effective for advanced melanoma. In this phase 2 clinical trial, the vaccine — in combination with Merck‘s immunotherapy drug Keytruda — reduced the risk of recurrence by 44%. However, this potential treatment is different from its Covid vaccine. That’s because it cannot be administered in advance of the illness, only after. Cancers are highly variable from person to person. This means each vaccine must be customised for each patient’s tumour, which adds complexity and risk. And even if successful, it’ll be years before Moderna is able to commercialise the treatment. A phase 3 study in melanoma patients is due to start this year, before other tumor types are targeted. Declining revenue Remarkably, Moderna designed its Covid vaccine in just two days, without even needing to touch a live virus. That demonstrates the speed and power of its platform. But it’ll have to be equally speedy in progressing its 36 ongoing clinical studies to make up for declining sales of its Covid vaccine. Revenue for 2022 is expected to be $18.4bn. Then sales are due to drop to around $9bn in 2023. This makes it tricky for me to accurately value Moderna stock today. If sales do drop by half in 2023, its current price-to-earnings (P/E) ratio of 7.3 would rise to approximately 47. But with a technology as potentially revolutionary as this, maybe P/E ratios aren’t appropriate yet. Foolish takeaway Nobody knows how much demand there’ll be for the company’s Covid vaccine — or exactly how much it’ll cost — when it enters the private market. Plus, Moderna isn’t the only biotechnology company progressing this type of technology. Pfizer, with its partner BioNTech, actually delivered the first authorised mRNA vaccine in the US. Indeed, there’s an ongoing patent dispute between Moderna and these two companies regarding the use of mRNA technology. This could present risks, depending on the outcome of this legal battle. All this makes me suspect that today’s rally in the shares might prove short-lived. I have a position in the stock, which I’m happy to keeping holding for now.
