When positive medical data triggers a severe market sell-off, the disconnect usually comes down to high expectations colliding with biotech reality. That dynamic played out on Thursday when Moderna shares tumbled as much as 25 percent after data from a late-stage trial of its personalized mRNA cancer vaccine leaked on social media, CNBC and BioPharma Dive reported.
By standard clinical measures, the Phase 3 study conducted with Merck was a notable scientific achievement. Adding the experimental vaccine, known as intismeran autogene, to Merck’s standard immunotherapy Keytruda reduced the risk of cancer recurrence or death by 42 percent in high-risk melanoma patients after surgical removal, according to study findings released ahead of the European Society for Medical Oncology conference in Madrid.
Two years after treatment, 82 percent of patients receiving the vaccine regimen were alive and free of cancer recurrence, compared to 70 percent on Keytruda alone, the companies reported. The combination also cut the risk of the disease spreading to distant organs or death by 38 percent.
The Wall Street expectation gap
Despite oncologists hailing the data as a major leap forward, investors reacted with heavy selling. Before Thursday’s leak, Moderna shares had surged more than 500 percent this year, driven by excitement over intismeran, according to CNBC. William Blair analyst Myles Minter described the sudden retreat as a classic ‘sell-the-news’ reaction, BioPharma Dive reported.
Wall Street models had set an aggressive benchmark. Analysts expected a risk reduction between 40 percent and 50 percent, meaning the 42 percent mark landed near the lower boundary of those projections. RBC Capital Markets analyst Trung Huynh noted the figure represented a slight drop from the 44 percent observed in earlier mid-stage trials, adding that while regulatory approval appears probable, commercial success remains far less certain.
Other market observers defended the therapy’s viability. BMO Capital Markets analyst Evan Seigerman wrote in a client note that the market drop reflected inflated expectations ahead of the full release rather than a flaw in the drug’s clinical efficacy, CNBC reported.
Manufacturing and clinical hurdles ahead
Beyond the numbers on Wall Street, the personalized nature of mRNA cancer therapies introduces logistical complications that investors are weighing carefully. Unlike mass-manufactured vaccines, each dose of intismeran must be custom-formulated to target up to 34 distinct genetic mutations found in a single patient’s tumor, ABC News reported.
That custom process requires sequencing a tumor and formulating individual doses, taking roughly six weeks or more to produce, Moderna President Stephen Hoge told ABC News. While Merck Chief Executive Officer Robert Davis told CNBC the companies hope to shorten that production window, the individualized process raises unresolved questions regarding production costs, pricing and hospital delivery systems.
Key medical questions also remain unresolved. Scientists do not yet know whether the vaccine helps patients live longer overall. Karen Knudsen, chief executive of the Parker Institute for Cancer Immunotherapy, told Scientific American that while the milestone is encouraging, researchers still need data on overall survival and patient quality of life.
Both drugmakers have submitted the data to the New England Journal of Medicine and are engaging with regulators to pursue approval, Scientific American reported. At the same time, Merck and Moderna are testing the vaccine in ongoing studies against lung, bladder and kidney tumors to determine whether individualized mRNA treatments can succeed beyond skin cancer.
