Pfizer Shares Rise Wednesday, mRNA Cancer Vaccine Prospects Boost Sentiment

Pfizer shares traded higher on Wednesday, rising in tandem with companies linked to mRNA cancer vaccines after Merck & Co. and Moderna announced their combination therapy of intismeran autogene and Keytruda showed positive recurrence-free survival results in melanoma patients.

Pfizer stock was among the best performers of the day. Why is PFE stock rising?

Pfizer's relationship with BioNTech makes it an mRNA proxy

Pfizer's gains today are largely driven by its position as the preferred mRNA proxy in the market, thanks to its long-standing partnership with BioNTech SE. That relationship has given Pfizer an equity stake in BioNTech, and the two companies continue to collaborate on updated vaccine formulations based on BioNTech's mRNA platform.

With Merck and Moderna validating that mRNA-based cancer treatments are a genuine clinical path forward, investors appear to be extending that optimism to Pfizer, given its ties to the underlying technology.

Merck and Moderna's melanoma trial hits key goals

Merck and Moderna on Wednesday reported early results from their Phase 3 INTerpath-001 study, which combined intismeran autogene with Merck's existing drug Keytruda. Doctors had surgically removed tumors from all patients in the trial, all of whom had Stage IIB-IV melanoma.

Based on data from an interim checkpoint built into the trial design, patients receiving the combination therapy performed significantly better than those receiving Keytruda alone, both in terms of how long patients went without their cancer returning and the time it took for the disease to spread to distant parts of the body, with both differences large enough to be considered statistically significant.

This is a milestone moment on multiple fronts. It is the first time a personalized neoantigen therapy has made it through a Phase 3 trial, and the first time any mRNA-based cancer treatment has done so. Additionally, no other Phase 3 study has previously shown a clear benefit over Keytruda alone in melanoma patients after complete surgical removal of tumors.

The study is not yet complete, and researchers intend to continue observing patients over time to gather more data, including whether the combination therapy extends overall survival.

PFE stock is rising

PFE price action: Pfizer shares rose 3.27% to $28.15 at the time of writing Wednesday. The stock is trading near its 52-week high of $28.74.