Amgen Discontinues Treatment With Vectibix in Trial of Combination Regimen

Amgen announced that it has discontinued treatment with Vectibix in the Phase III PACCE trial evaluating the addition of Vectibix to standard chemotherapy and Avastin for treating first-line metastatic colorectal cancer.

The decision to discontinue Vectibix (panitumumab) treatment in the trial was based on a preliminary review of data from a preplanned interim efficacy analysis scheduled after the first 231 events (death or disease progression). This analysis revealed a statistically significant difference in progression-free survival in favor of the control arm. An unplanned analysis of overall survival also demonstrated a statistically significant difference favoring the control arm. Additional analyses are ongoing, and Amgen said it plans to present the results at an upcoming scientific forum.

"Patient safety is Amgen's top priority. For this reason, we have decided to discontinue Vectibix treatment in the PACCE trial while we complete additional analyses of these preliminary results," Roger Perlmutter, executive vice president of R&D at Amgen, said. "We had hoped that adding Vectibix to the current U.S. standard-of-care for patients newly diagnosed with [metastatic colorectal cancer] would improve outcomes without excessive added toxicity. Unfortunately, it appears that adding Vectibix to Avastin, when used in combination with oxaliplatin- or irinotecan-based chemotherapy, increased toxicity, without improving efficacy."

Amgen has notified the FDA and study investigators that patients who are still receiving treatment in the PACCE study should discontinue Vectibix treatment. Patients will have the option of continuing per-protocol treatment without Vectibix.

In January Amgen informed investigators and regulatory authorities about safety information arising from a planned interim safety analysis of the PACCE trial. A review of the interim analysis showed an increased incidence of grade 3 severe events of diarrhea, dehydration and infections in the Vectibix-treated patients.

Amgen said it is continuing to explore Vectibix as a single biologic combined with chemotherapy in other Phase III trials. No other clinical studies are being modified at this time.