Dendreon Corp., maker of the prostate cancer drug Provenge, dropped to its lowest value in four months after Johnson & Johnson’s rival medicine Zytiga helped high-risk patients in a study.
Dendreon fell 11 percent to $7.65 at the close of trading in New York. The shares have risen less than 1 percent this year. Zytiga, approved last year to treat metastatic prostate cancer, helped eliminate tumors in people whose malignancy hadn’t yet spread beyond the prostate gland, New Brunswick, New Jersey-based J&J said yesterday.
“Zytiga looks good in early stage therapy in high risk patients, again squeezing the window for Provenge use,” David Nierengarten, a San Francisco-based analyst with Wedbush Securities Inc., said in an e-mail.
Provenge was approved in April 2010 as the first therapy in the U.S. that trains the body’s immune system to attack cancer cells as if they were a virus. The treatment, which costs $93,000, was cleared for patients with advanced cases of the disease after the Seattle-based company’s three-year effort to persuade the Food and Drug Administration to back the medicine.
Dendreon plunged 25 percent on May 8, the most in six months, after the company said growth this year will be “modest” and its first-quarter loss fell short of estimates. The drugmaker also disclosed in a May 7 filing that the U.S. Securities and Exchange Commission opened a probe that may be related to the company’s withdrawn revenue estimate last year, when slower-than-expected sales of Provenge prompted the dropping of the $350 million to $400 million projection.
“We do not know the specific focus of the investigation,” Tricia Larson, a Dendreon spokeswoman, said in an e-mail yesterday. “We are cooperating fully with the SEC and will continue to do so.”