Plaintiffs’ attorneys stepped up pressure on Merck on cases related to its withdrawal of Vioxx, the anti-inflammatory drug, sending the US drugmaker’s shares plummeting again on Monday.
Investors were spooked again on fears of Merck litigation and increasing scrutiny of its efforts to market Vioxx over the past five years, in spite of lingering questions about its cardiovascular dangers.
Merck voluntarily withdrew the $2.5bn-a-year seller from the market in September after a company study found it doubled the risk of heart attacks and strokes after 18 months continuous use.
Merck has seen one-third of its market capitalisation slashed, about $35bn in market value, since the Vioxx withdrawal on September 30. Its shares fell almost 10 per cent to $28.28 in New York on Monday.
On Friday, the group warned that selective documents protected by court orders barring public release would leak into the public sphere. “Past experience of other companies in such situations suggests that documents will be deliberately presented out of context to advance the interest of the parties who have started Vioxx litigation,” Merck said.
“Merck should come clean with the public,” said Andy Birchfield, of Beasley Allen, and lead attorney in the first Vioxx lawsuit case scheduled for trial next month. “If Merck is concerned about documents selectively being released in a manner taken out of context, the remedy is for Merck to release all documents so the public can evaluate them.”
Mr. Birchfield said on Monday that even “non-confidential” documents show Merck attempted to downplay Vioxx’s cardiovascular risks for years.
He called “ridiculous” the group’s assertion that court-protected documents were being seen and taken out of context.
Continuing scrutiny and attacks on Merck’s motives with Vioxx also obscured some positive clinical study results on an important new product – an experimental vaccine for cervical cancer in women.
On Monday, Merck presented results of a study involving almost 2,400 women showing one form of its experimental vaccine prevented pre-cancerous lesions in women.
The vaccine works to prevent infection of the human papillomavirus (HPV). Persistent HPV infection has been linked to the formation of lesions that can become cervical cancer.
The trial, vaccinating for one HPV strain called HPV 16, prevented lesions in 100 per cent of the women and over 48 months prevented persistent HPV infection in 94 per cent.