Pfizer's share price plunged after higher-than-expected mortality and side effects reported during a clinical trial led it to scrap a drug it had been developing since 1992.
Novartis is confronting such concerns head-on with large clinical trials that try to tease out potential side effects and will take the rare step of directly comparing Prexige, formerly known as Cox-189, to both Celebrex and Vioxx.
Clinical trials and post-marketing monitoring of Gardasil, made by Merck, and Cervarix, made by GlaxoSmithKline, showed side effects similar to placebo.