Drugmaker Pfizer Inc (PFE.N) and France’s Valneva (VLS.PA) will stop testing a Lyme disease vaccine in roughly half of U.S. patients in a late-stage study, the companies said, citing a breach of clinical trial guidelines by a third-party contractor.
The joint statement on Friday did not disclose the number of patients affected but analysts at brokerage Rx Securities estimated it could impact about 2,000 participants.
The decision could delay the time to approval of a vaccine that Valneva expects could become a blockbuster shot as infections rise globally due to a burgeoning population of ticks, which usually cause Lyme disease.
