Ebb & Flow
Amgen Inc. got its biggest one-day pop in four years on last week's positive Phase III data for denosumab to prevent skeletal-related events associated with breast cancer. The company announced the data after market close on Tuesday, and the next day Amgen shares climbed $7.27 (14%) to $59.38, adding $7.3 billion in market cap.
Achieving superiority in the trial drove the bounce, buysiders told Ebb & Flow. The primary endpoint was non-inferiority to Zometa zoledronic acid from Novartis AG (NYSE:NVS; SIX:NOVN), but denosumab was superior on the primary endpoint of time to the first on-study skeletal-related event (SRE).
"The expectation for superiority was extremely low; everybody thought it was going to be equal to Zometa. This is a huge surprise and changes the market potential," said Sven Borho of OrbiMed Advisors.
venBio's Kurt von Emster agreed. "This further enhances the already high likelihood of approval in PMO [postmenopausal osteoporosis] in the next few months," he said.
von Emster added it was important that the rates of osteonecrosis of the jaw (ONJ) were equal across both treatment arms. ONJ was not reported in previous Phase III denosumab studies, but this time the dosage was 12 times higher, Amgen VP of Global Development Roy Baynes told Ebb & Flow.
Several milestones this half could keep Amgen's momentum going.
On Aug. 13, FDA's Reproductive Health Drugs Advisory Committee will meet to discuss a BLA for denosumab to treat and prevent PMO and to treat and prevent bone loss in patients undergoing hormone ablation for prostate or breast cancer. The PDUFA date is Oct. 19.
Approval in PMO is widely anticipated on the Street, although Oliver Marti of Columbus Circle Investors cautioned that FDA could delay action, given the size of the filing.
Meanwhile, Phase III data in solid tumors/multiple myeloma are due by year end and data from a Phase III trial in prostate cancer are expected in 2010.