Pfizer Advances in C. diff Vaccine Development and Pneumococcal Shot Progress
Pfizer recently updated sell-side analysts on its vaccine pipeline, focusing on a second-generation Clostridioides difficile (C. diff) vaccine currently in Phase 2. Despite a setback with a first-generation vaccine in March 2022, where the primary endpoint was not met, secondary endpoint data suggested reduced disease severity. Pfizer is now exploring updated formulations, including a two-dose regimen instead of three, with immunogenicity data expected in 2025 and potential advancement into Phase 3 by the end of that year.
Goldman Sachs analyst Chris Shibutani maintains a Buy rating on Pfizer, with a price target of $33. Shibutani noted the objective for a potential Phase 3 study would be to reduce the severity of C. diff infections rather than prevent the disease. Pfizer estimates approximately 500,000 C. diff infections annually in the U.S., with no current vaccine options available, highlighting an unmet medical need.
In addition to the C. diff vaccine, Pfizer's fourth-generation 25-valent pneumococcal vaccine (PCV) is progressing in Phase 2. Shibutani recalled encouraging immunogenicity data from Phase 1, particularly for serotype 3. Pfizer's second-generation C. diff vaccine, PF-07831694, targets C. diff toxins A and B, aiming for a more potent and durable formulation with a two-dose regimen.
Pfizer has advanced one of three updated second-generation candidates to Phase 2 based on Phase 1/2 safety and immunogenicity data. The Phase 2 trial will evaluate the immunogenicity and safety of the two-dose regimen, with data expected in 2025. Pfizer is currently the furthest along in C. diff vaccine development, with competitors like Idorsia Pharmaceuticals, Vaxxilon, and Matrivax Research & Development Corporation in earlier stages.
Despite the progress, Pfizer's stock has dropped over 11.5% year-to-date, with investors able to gain exposure through SPDR S&P 500 SPY and Vanguard S&P 500 ETF VOO. At the last check, PFE stock was up 0.82% at $26.58.