Amgen (Nasdaq: AMGN) today announced top-line results from a randomized Phase 3 trial evaluating Vectibix® (panitumumab) as a first-line treatment in patients with recurrent and/or metastatic squamous cell head and neck cancer. The data showed the addition of Vectibix to platinum-based chemotherapy did not result in a statistically significant improvement in overall survival, the primary endpoint, compared to chemotherapy alone [median 11.1 months versus 9.0 months, hazard ratio 0.87 (95% CI: 0.73, 1.05)]. Therefore, the study did not meet its primary endpoint. Secondary endpoints of progression-free survival [median 5.8 months versus 4.6 months, hazard ratio 0.78 (95% CI: 0.66, 0.92)] and objective response rate (36 percent versus 25 percent) were numerically improved but were not tested for statistical significance.
"The outcome of this study is disappointing. However, Vectibix remains an important monotherapy treatment option for patients with metastatic colorectal cancer whose disease has progressed on other therapies," said Roger M. Perlmutter, M.D., Ph.D., executive vice president of Research and Development at Amgen.
The SPECTRUM study enrolled 658 patients who were randomized to receive a standard platinum-based chemotherapy (cisplatin and 5-FU), with or without Vectibix (9 mg/kg) every three weeks. The primary endpoint was overall survival. The secondary endpoints included progression-free survival, objective response rate, duration of response, time to progression, time to response, patient reported outcomes and safety.
The most frequently reported adverse events in the Vectibix plus chemotherapy arm included nausea, rash, neutropenia and vomiting, as anticipated for this combination therapy.
Detailed results from the study will be presented at the 35th European Society for Medical Oncology (ESMO) Congress scheduled for October 8-12 in Milan, Italy.