Moderna (MRNA -2.46%) has brought in billions thanks to its coronavirus vaccine. Now, though, the biotech company has to show investors it can excel beyond the coronavirus portfolio. That's because we're heading toward a post-pandemic world, and Moderna's vaccine revenue is set to slip.

One of Moderna's programs that have spurred excitement among investors is its personalized cancer vaccine candidate. The company recently reported positive results from a melanoma trial using the candidate as part of a combination therapy. The news didn't lift Moderna's share price, though. Investors may be worried Moderna is about to face the same challenge as other biotechs and pharma companies. Let's find out more.

Timeline to commercialization

What is this challenge that drugmakers and vaccine companies face? A lengthy timeline to commercialization. It can take many years to develop, test, and then win regulatory approval for a product.

Yes, Moderna has worked on its technology for years. But the company brought its coronavirus vaccine from the drawing board to commercialization in less than a year. Investors have gotten used to speed from the company.

Moderna also can quickly update its vaccine with new strains thanks to its messenger RNA technology. That's because Moderna doesn't have to grow proteins in a factory as it would for a traditional vaccine. Instead, mRNA technology involves injecting instructions into the body so that the body produces proteins to prevent or fight disease.

And Moderna has taken steps to get even faster. For example, it recently announced the acquisition of OriCiro Genomics. Moderna told FiercePharma that OriCiro's technology might help it cut manufacturing time by 30%.

All of this applies to Moderna's coronavirus vaccine right now. And it involves the actual production of vaccine products. But this doesn't mean the clinical trials process across treatment areas will be equally speedy.

And we may be seeing this in the case of the personalized cancer vaccine. Moderna's trial included 157 subjects. Researchers gave 107 of them mRNA-4157 in combination with Merck's Keytruda. The remaining 50 patients received only Keytruda. Recurrence or death occurred in 22.4% of the combination patients and in 40% of the Keytruda-only patients. That was after a follow-up period of about 24 months.

The recurrence-free survival rate was 78.6% in the combination group at 18 months -- and 62.2% in the control group.

Trial size and follow up

Data were positive. But that doesn't mean Moderna will launch its potential product anytime soon. The two issues here that may equal a much longer path to market than the coronavirus vaccine have to do with trial size and follow-up time. Regulators may want to see more subjects treated and follow them for longer periods of time.

Moderna has already said it will launch a phase 3 study this year in melanoma and expand into various types of tumors as quickly as possible.

So what does this mean for Moderna and its investors? Yes, Moderna may continue to be faster than others in some areas thanks to its mRNA technology. But Moderna still faces the same challenge -- time to commercialization -- as peers when it comes to developing certain products.

No matter what technology is used, it's still necessary to enroll a significant number of patients in trials and monitor them over time. All of this means investors shouldn't be too disappointed if Moderna can't roll out every product as quickly as the coronavirus vaccine. That product was an exception, quickly needed during a health crisis.

That said, Moderna's technology does give it an edge in production and in key areas, such as updating a current coronavirus or flu vaccine with a new strain. So Moderna can continue to move quickly there.

Overall, Moderna shares may struggle to take off as the company navigates this time of transition -- from the pandemic world to the post-pandemic environment. But the long-term picture remains bright. So, today, Moderna stock represents an opportunity that may pay off over time.