Amgen Drug an Improvement

Denosumab Shows Superiority To Zometa

On July 7, 2009, Amgen (AMGN - Analyst Report) released results from a phase III program testing its experimental osteoporosis drug, denosumab, in a head-to-head trial against Novartis’ (NVS - Snapshot Report) Zometa (zoledronic acid) for the treatment of bone metastases in just over 2,000 patients with advanced breast cancer.

The primary endpoint was to evaluate if denosumab is non-inferior to Zometa with respect to the first on-study skeletal related event (SRE) in patients with advanced breast cancer and bone metastases. Secondary endpoints were to evaluate if denosumab was superior to Zometa with respect to the first on-study SRE, as well as first-and-subsequent on-study SREs, and to assess the safety and tolerability of denosumab compared with Zometa.

Patients enrolled in the study were randomized in a 1:1 ratio to receive either 120 mg of denosumab subcutaneously every four weeks (Q4W) or Zometa administered intravenously at a dose of 4 mg single, 15 minute infusion every four weeks as per the labeled use.

Results of the study show that Amgen’s denosumab was superior to Zometa in the primary endpoint of first on-study SRE with a hazard ratio of 0.82 (18% reduction vs. Zometa), and in the secondary endpoint of first-and-subsequent SRE with a hazard ratio of 0.77 (23% reduction vs. Zometa). Incidence of adverse events and serious adverse events was consistent with what has previously been reported for these two agents, as well as incidence of a serious side effect, osteonecrosis of the jaw (ONJ).

Bone metastases, the spread of tumors to the bone, are a serious concern for advanced breast cancer patients, with incidence rates as high as 75%. When cancer spreads to the bone, the growing cancer cells weaken and destroy the bone around the tumor. This damage can result in a number of serious bone complications, collectively called SREs. Novartis’ Zometa, one of the most widely used pharmaceutical products to prevent SRE in at risk cancer patients, posted sales of $1.4 billion in 2008.

These clinical results, which demonstrate Amgen’s denosumab is superior to Zometa, are clearly very positive for the company, and reinforce our previous belief that the drug is a multi-billion dollar blockbuster. The U.S. FDA is schedule to rule on the potential approval of denosumab in October 2009. An advisory panel will discuss the drug on August 13, 2009.

Email	Print	Share	RSS	Rate Pos	Rate Neg	Comment