Patients with unresectable or metastatic melanoma who were treated with Keytruda (pembrolizumab) in a pivotal clinical trial showed superior and sustained time to disease progression when compared to those treated with Yervoy (ipilimumab).
Among patients who discontinued treatment at two years, 91 percent were alive and without disease progression after a median follow-up of nearly 10 months.
These results are from KEYNOTE-006 (NCT01866319), the Phase 3 study investigating Keytruda’s safety and efficacy relative to Yervoy in melanoma patients who were either treatment-naive or had received one prior line of therapy.
Both drugs belong to the class of immunotherapy drugs, with Keytruda targeting the immune checkpoint PD-1 and Yervoy CTLA-4. These immune checkpoints are often highly expressed in a plethora of cancers, and act to inhibit immune system responses.
The findings were recently presented at the 2017 American Society Of Clinical Oncology (ASCO) Annual Meeting, which ran June 2-6 in Chicago, in an oral presentation titled “Long-term outcomes in patients (pts) with ipilimumab (ipi)-naive advanced melanoma in the phase 3 KEYNOTE-006 study who completed pembrolizumab (pembro) treatment.”
KEYNOTE-006 is a ranomized, controlled trial that enrolled 834 patients with advanced melanoma to receive either Keytruda every two weeks, Keytruda every three weeks, or Yervoy every three weeks.
Results published in the New England Journal of Medicine in 2015 showed that both Keytruda regimens significantly extended the time to disease progression and one-year survival rates compared to Yervoy. Also, more patients in the Keytruda arms responded to treatment, and fewer had severe treatment-related adverse events.
At the time, these findings led to Keytruda being approved as first-line treatment for advanced melanoma. Now, researchers provided updated long-term data fom KEYNOTE-006, showing that patients who received Keytruda continue to show superior survival outcomes after nearly three years of follow-up (33.9 months).
“With longer-term follow-up in this study, we are continuing to see superior survival with Keytruda, including in patients whose treatment has concluded,” Dr. Caroline Robert, head of dermatology at Gustave Roussy, Villejuif, and Paris-Sud University Cancer Campus, Grand Paris, said in a press release. “Importantly, these findings also continue to reaffirm the established safety profile for Keytruda.”
The numbers showed that therapy with Keytruda was associated with a 30 percent improvement in survival. Among Yervoy-treated patients, 39 percent were alive 33.9 months after beginning treatment; this number increased to 50 percent in patients who received Keytruda.
Researchers also observed that Keytruda almost doubled the rate of progression-free survival (PFS) at 33.9 months — 31%, compared to 14% for Yervoy.
“Keytruda continues to demonstrate improved overall survival compared to ipilimumab, and the findings … presented at ASCO reinforce the benefit of Keytruda in the treatment of advanced melanoma,” said Dr. Roger Dansey, senior vice president and therapeutic area head, oncology late-stage development, Merck Research Laboratories.
The clinical development of Keytruda is taking place in more than 30 tumor types, covering a total of more than 500 clinical trials. In a large fraction of the studies (roughly 300), Keytruda is being tested in combination with other cancer therapies. Currently, Keytruda is an approved therapy for advanced melanoma in more than 50 countries, including the United States and across Europe.