The following article originally appeared in FiercePharma and was written by Angus Liu

Moderna’s mRNA COVID-19 vaccine candidate was the first U.S. shot to enter late-stage testing, but that doesn’t necessarily mean it has the brightest future of all.

The high possibility of multiple emergency authorizations for coronavirus vaccines by year-end spells plenty of competition—and an outlook for Moderna that’s less rosy than expected, SVB Leerink analyst Geoffrey Porges and his team wrote in an investor note, citing R&D and vaccine experts.

“[E]arlier entry of another large, established global pharma competitor adds an additional degree of uncertainty” to the potential sales for Moderna’s candidate, mRNA-1273, according to the note, which summarized comments from experts at an International Society for Vaccines’ virtual event and from a separate call with three key opinion leaders in immunology and vaccine development.

The FDA’s emergency authorizations will likely be granted on data from relatively small numbers of patients and limited follow-up time, so there’s likely to be “limited differentiation” among the various sets of vaccine data, the analysts wrote.

And that, in turn, will “increase the importance of clinical and commercial execution, a disadvantage for Moderna versus entrenched Big Pharma players,” the note stated.

Moderna launched its phase 3 trial of mRNA-1273 in late July and expects to complete it in late 2021, suggesting a potential full approval in early 2022. But like the biotech itself, the experts were bullish on the chance of an emergency authorization based on preliminary data by the end of 2020.

Moderna’s likely not the only one looking at that kind of a timeline, though. The Financial Times reported Monday that the U.S. government is already considering a possible emergency authorization for AstraZeneca’s adenovirus vector-based vaccine, though the British government and AstraZeneca itself denied that it was in such talks with the administration.

That report, combined with experts’ view, prompted the SVB Leerink team to adjust their prediction to allow for earlier competition from non-mRNA vaccines, likely also by year-end.

In fact, all three specialists Porges’ team interviewed named the protein subunit vaccines with an adjuvant as their favorite class among the various COVID-19 vaccine approaches.

Leaders in this field include a collaboration between two of the world’s largest vaccine makers—Sanofi and GlaxoSmithKline—which expects to obtain a potential approval as early as June 2021. Maryland biotech Novavax is looking to advance a similar shot into phase 3 testing this fall, with $1.6 billion in grant funding from Operation Warp Speed.

Competition is also brewing within the mRNA class, with Pfizer and German partner BioNTech close behind Moderna; their BNT162b2 candidate is also in large-scale phase 3 testing. And the Pfizer/BioNTech shot is currently the only vaccine to have demonstrated responses in both CD4+ and CD8+ T cells in human studies, Porges noted.

The first wave of emergency authorizations will likely be based on limited data, which could make it difficult for products to differentiate among themselves, Porges said. That means commercial expertise and infrastructure could be key. Moderna, which doesn’t have a single marketed product, doesn’t have the commercial prowess of a Big Pharma player like Sanofi, Pfizer or AstraZeneca.

That lack of other products also means mRNA-1273 represents the bulk of Moderna’s revenue opportunity in the near term. Porges’ team says it’s very likely to gain an FDA approval “given the permissive regulatory environment” around COVID-19 vaccine candidates in general, and that it could attract “a substantial early bolus of patients.”

But the medium or long term could be a different story, the analysts noted, “given the breadth of competitors expected to enter the market.”

In addition, mRNA-1273 needs to be shipped and stored at -20 °C, and it can only be stored at 2°C to 8°C in a clinician’s office for up to one week. That complexity in shipping and storage requirements, compared with some traditional vaccines, could be an “especially relevant consideration after the immediate pandemic period and for patient populations outside of high-income countries,” Porges wrote.