(Reuters) - Valeant Pharmaceuticals Inc's (VRX.TO) share slumped for the second straight day on Wednesday, a day after influential shortseller Citron Research said the Canadian drugmaker used specialty pharmacies to create "phantom sales".
Valeant's U.S.-listed shares (VRX.N) closed down 19 percent on Wednesday and fell as much as 18 percent to a low of $96.78 on Thursday.
At that price, about $17 billion of Valeant's market value has been wiped out since Tuesday's close.
Citron's report on Wednesday highlighted risks in the company's business model based on rapid expansion through acquisitions and aggressive price hikes. Valeant has refuted the allegations.
However, only one of the 23 analysts covering Valeant's U.S.-listed stock has lowered their rating so far. Sixteen analysts still rate the stock "buy" or higher, according to Thomson Reuters data.
UBS Securities and Bank of America Merrill Lynch reiterated their "buy" ratings, saying Valeant's clarifications should help the stock recoup some losses.
Valeant said on Wednesday it does not record sales of drugs stocked as inventory at such pharmacies in its financial reports and that sales are recorded only when the product is dispensed to the patient.
Still, BMO Capital Markets analyst Alex Arfaei downgraded the stock to "market perform" from "outperform", saying that the company's specialty pharmacy structure could not be defended.
"Valeant's structure may not be illegal, but we find it aggressive and questionable," Arfaei wrote.
Reporting by Amrutha Penumudi in Bengaluru; Editing by Savio D'Souza