Amgen's multiple myeloma therapy Kyprolis is on track for approval in a much broader patient population after positive interim results in a phase III trial.
The ASPIRE study compared Kyprolis (carfilzomib) to placebo on top of Celgene's Revlimid (lenalidomide) and dexamethasone therapy in patients with relapsed multiple myeloma, and found Amgen's drug significantly improved progression-free survival from 17.6 to 26.3 months.
While the data is not yet mature the trial also showed a trend towards an overall survival benefit with Kyprolis, and Amgen believes it could be in a position to file for approval of the new indication in the first half of 2015.
Kyprolis - which was acquired by Amgen as part of its purchase of Onyx last year for $10.4bn, is already enjoying fairly buoyant growth in its current third-line multiple myeloma indication, with second-quarter sales rising 15 per cent to $78m, although there is a degree of plateauing compared to earlier growth rates.
The positive ASPIRE data will drive the next “inflection point” in the product's growth trajectory, according to Tony Hooper, Amgen's head of global commercial operations, as the product is approaching peak penetration in the third-line setting.
Moving from third- to second-line use will expand the potential patient population eligible to receive Kyprolis by two to three times, he said.
Amgen and Onyx are also awaiting the results of the phase III FOCUS study in relapsed refractory multiple myeloma, and recently completed patient enrolment in ENDEAVOUR, which is comparing Kyprolis to Takeda/Millennium Pharmaceuticals' Velcade (bortezomib) - on top of background therapy with dexamethasone - in relapsed patients.
A third trial called CLARION is looking at the potential of Kyprolis as a first-line myeloma therapy, which once again would expand the market opportunity two- or three-fold, while Amgen and Onyx are also developing a once-weekly formulation that would be more suitable in this earlier setting than the current twice-weekly version.
Amgen reported data from the CHAMPION 1 study at this year's American Society of Clinical Oncology (ASCO) conference which showed a weekly dose of the drug appeared to be as effective as the twice-weekly regimen when given alongside cyclophosphamide and dexamethasone.
Drugs such as Velcade and Revlimid have transformed the therapy of multiple myeloma in recent years, with patients living two to three times longer than they did a decade ago.
However, “In the treatment of patients with multiple myeloma, periods of remission become shorter following each treatment regimen, underscoring the need for new options,” commented Pablo Cagnoni, president of Amgen's Onyx subsidiary.
“The ability of novel therapies to produce deep and durable responses may, one day, transform this uniformly fatal disease to one that is chronic and manageable,” he added.