moderna announces rsv data

On Tuesday, January 17, Moderna announced positive topline data from its ConquerRSV Phase 3 pivotal efficacy trial of mRNA-1345, an investigational mRNA vaccine targeting respiratory syncytial virus (RSV) in older adults. Given the positive data, Moderna announced that they will apply for U.S. regulatory approval in the coming months, thus propelling themselves into the fierce race among pharmaceutical giants to supply the world with a vaccine for RSV – an illness for which there is no commercially approved vaccine. 

RSV is a highly contagious seasonal respiratory virus and a leading cause of lower respiratory tract infections and pneumonia. It causes a particularly large burden of disease in infants and older adults. RSV has the potential to cause severe disease, with an estimated 5.2 million cases and nearly 500,000 hospitalizations in adults 60 years or older reported across high-income countries in 2019. Each year in the U.S., approximately 60,000 to 120,000 older adults are hospitalized, and 6,000-10,000 of those hospitalizations result in death due to RSV infection. 

Moderna’s RSV vaccine demonstrated efficacy of 83.7% against RSV lower respiratory tract disease (RSV-LRTD). In assessing efficacy, Moderna counted cases of confirmed RSV infection plus at least two symptoms, such as cough, fever or difficulty breathing. Further, the other primary efficacy endpoint against severe RSV-LRTD (defined by three or more symptoms) was also met, with a vaccine efficacy of 82.4%. What’s more, in a review of available safety data conducted by an independent Data and Safety Monitoring Board (DSMB), it was found that the vaccine was well tolerated with no safety concerns identified. 

Moderna’s Phase 3 trial, appropriately named ConquerRSV, started early last year and enrolled roughly 37,000 people ages 60 and older in 22 countries including the U.S. Roughly half of the participants in the double-blind study received a placebo and the others, mRNA-1345. The interim analysis was based on the 64 accrued cases of RSV-LRTD with two or more symptoms, of which 55 occurred in the placebo group and 9 occurred in the mRNA-1345 group. With regard to severe RSV-LRTD, 20 cases with three or more symptoms were reported, of which 17 were observed in the placebo group compared with three cases observed in the mRNA-1345 group. The trial is ongoing, and Moderna’s management stated that additional efficacy analyses are planned as cases accrue.

Moderna’s President, Dr. Stephen Hoge, said that the vaccine’s efficacy appeared to hold up for at least six months, and could be longer pending follow-up analyses. Moderna envisions the RSV vaccine as a once-yearly shot that is administered ahead of the typical RSV season, following a similar administration cadence to a flu shot or a COVID booster. 

However, unlike COVID and the flu, there is no approved vaccine against RSV. That being said, the RSV vaccine space is incredibly competitive, with some of the world’s largest pharmaceutical companies currently vying to be market leaders in the nascent space. Pfizer and GSK are leading the pack, with both companies having released topline Phase 3 data last fall. Pfizer’s vaccine is focusing its attention on both the infant subpopulation and older adult population while GSK’s focuses only on older adults. J&J is also a contender, expecting to read out Phase 3 results this winter. In October, GSK reported that its shot was 82.6% effective overall but 94.1% effective in patients with severe disease. GSK defined severe disease as having two or more lower respiratory conditions, unlike Moderna which defined severe disease as three or more. In August, Pfizer reported 66.7% efficacy against RSV overall and 85.7% efficacy against severe disease. Pfizer defined severe disease in the same way as Moderna. In an interview with FierceBiotech, Moderna Senior Vice President of Respiratory Vaccines Francesca Ceddia commented that while she cautioned against making comparisons without data, she believes Moderna’s shot is most comparable to GSK in terms of efficacy. To this end, it appears that in the battle against multiple Goliaths, Moderna has proven itself a worthy opponent. 

However, unlike Pfizer and GSK, Moderna has not yet received a priority review tag for its RSV shot. Nonetheless, Moderna’s Ceddia remarked that the company plans to use one of the two it has on its shelf (one having been purchased and the other earned due to Moderna’s success with its COVID-19 shot). Pending regulatory approval, this means that Moderna’s shot could become available by early 2024, the company said. In essence, Moderna’s RSV vaccine could then see commerciality by the 2024/25 RSV season, as the high majority of individuals get seasonal vaccinations in the early- to mid-fall. So, while GSK and Pfizer may see their vaccines approved in time for the 2023/24 RSV season, Moderna will be fast on their heels.

While none of the leading companies have given any guidance with respect to pricing, it is expected that the global RSV market will be worth as much as $10 billion by 2028. To this end, as the differences between the vaccines are negligible, all three companies can expect to grab onto a large piece of the pie. 

Looking forward, specifically at Moderna, the company plans to initiate a Phase 1 pediatric trial of its vaccine that targets both RSV and hMPV. Like RSV, hMPV is a major cause of lower respiratory tract infection in the pediatric population and a common cause of morbidity and mortality in immunocompromised patients. Furthermore, Moderna is also looking at creating a combination RSV and COVID vaccine along with a combination RSV, COVID and flu vaccine. If efficacious, these vaccines could act as a one-stop solution for the dominant winter illnesses that are designated as high-risk for older adults and immunocompromised individuals. 

With these positive results, Moderna once again proves the power of its mRNA platform with respect to respiratory illnesses. Indeed, this data continues the strong momentum for the company following positive Phase 1 data from their rare diseases arm this past September, and positive Phase 2 data from their personalized cancer vaccine (PCV) in December.

Looking to the short-term, Moderna will hope to continue its momentum even further as it has major catalysts in the barrel, including an initial data readout from the company’s influenza vaccine scheduled for the first quarter of this year and additional information with respect to strategic approach to the company’s cancer program, which could come as soon as the 2022 fourth quarter and full-year earnings call, which is likely to take place in the last week of February.