Dive Brief:
- Pfizer and partner Valneva said Monday they plan to seek regulatory approval of their experimental Lyme disease vaccine even though the shot missed its main goal in a late-stage trial.
- Pfizer and Valneva said that by one analysis, the vaccine, LB6V, was 73% effective compared to a placebo at preventing Lyme disease 28 days after the fourth dose. A second analysis found it roughly 75% effective one day after the fourth dose. However, the vaccine still failed to meet its primary objective because fewer-than-expected Lyme disease cases accrued over the course of the study period.
- Despite the setback, the partners characterized the efficacy results as “clinically meaningful” and said they’re “confident in the vaccine’s potential.” Approval applications are planned. Still, Valneva shares fell by more than 35% in early trading Monday.
Dive Insight:
Lyme disease is spread by infected ticks and can be treated with antibiotics if caught early. But if it isn’t, the disease can cause long-term health complications, such as joint pain or heart inflammation. And some who get antibiotics can experience a kind of post-treatment syndrome involving brain fog and fatigue.
The Centers for Disease Control and Prevention has estimated that around 476,000 people contract disease annually in the U.S. But there are currently no preventive shots for it, as the only vaccine once sold for the condition — GSK’s Lymerix — was pulled from the market amid criticism of its safety and low demand.
Lymerix’s failure soured many vaccine developers on the idea of investing in a new candidate. That’s left Pfizer and Valneva’s shot as the most advanced candidate in testing, and heightened anticipation of the Phase 3 readout.
The mixed results reported Monday come as vaccine makers have faced considerably higher regulatory scrutiny than they have in the past. Still, Health and Human Services Secretary Robert F. Kennedy Jr. has highlighted the need for treatments to address the disease, suggesting the Pfizer and Valneva’s application “could be met with a sympathetic ear,” wrote RBC Capital Markets analyst Trung Huynh, in a Monday note to clients.
In addition, Vinay Prasad, the Food and Drug Administration vaccine chief who has intervened in multiple regulatory reviews, is leaving the agency at the end of April. The Trump administration has reportedly been steering away from vaccine controversies ahead of the midterm elections, too.
But Huynh noted that, even if approved, Pfizer and Valneva may have a tough time generating sales. According to Hyunh, “commercial uptake of a [Lyme disease] vaccine has been historically tepid, at best.” The firm expects annual sales to peak at around $525 million.
