Merck announced the European Commission has approved Keytruda, the company’s anti-PD-1 therapy, for the treatment of adult patients with relapsed or refractory classical Hodgkin lymphoma (cHL) who have failed autologous stem cell transplant (ASCT) and brentuximab vedotin (BV), or who are transplant-ineligible and have failed BV. The approval allows marketing of Keytruda in all 28 EU member states plus Iceland, Lichtenstein and Norway, at the approved dose of 200 mg every three weeks until disease progression or unacceptable toxicity.
“Today’s approval brings an important new treatment option to patients in Europe with classical Hodgkin lymphoma who have not responded to existing therapies,” Dr. Roger Dansey, senior vice president and therapeutic area head, oncology late-stage development, Merck Research Laboratories said. “This milestone underscores our commitment to evaluating Keytruda in diseases with unmet need facing the hematology community.”
The approval was based on data in 241 patients from the KEYNOTE-087 and KEYNOTE-013 trials. These multicenter, open-label studies evaluated patients with cHL who failed ASCT and BV, who were ineligible for ASCT because they were unable to achieve a complete or partial remission after salvage chemotherapy and failed BV, or who failed ASCT and did not receive BV.
Both studies included patients regardless of PD-L1 expression. Patients with active, non-infectious pneumonitis, an allogeneic transplant within the past five years (or more than five years but with graft-versus-host-disease [GVHD]), active autoimmune disease or a medical condition that required immunosuppression were ineligible for either trial. The major efficacy outcome measures, overall response rate (ORR) and complete remission rate (CRR), were assessed by blinded independent central review according to the 2007 revised International Working Group (IWG) criteria. Secondary efficacy outcome measures were duration of response, progression-free survival, and overall survival.
In KEYNOTE-087, 210 patients received Keytruda at a dose of 200 mg every three weeks until unacceptable toxicity or documented disease progression. Eighty-one percent of patients were refractory to at least one prior therapy, including 35 percent who were refractory to first-line therapy. Additionally, 61 percent of patients had undergone prior ASCT, 38 percent were transplant ineligible; 17 percent had no prior BV use and 36 percent of patients had prior radiation therapy. Efficacy analysis showed an ORR of 69 percent (95% CI: 62.3, 75.2) with a CRR of 22 percent and a partial remission rate (PRR) of 47 percent. The median follow-up time was 10.1 months. Among the 145 responding patients, the median duration of response was 11.1 months (range 0.0+ to 11.1), with 76 percent of responding patients having responses of six months or longer.
In KEYNOTE-013, 31 patients received KEYTRUDA at a dose of 10 mg/kg every two weeks until unacceptable toxicity or documented disease progression. Eighty-seven percent of patients were refractory to at least one prior therapy, including 39 percent who were refractory to first-line therapy. Seventy-four percent of patients had undergone prior ASCT, 26 percent were transplant ineligible, and 42 percent of patients had prior radiation therapy. Efficacy analysis showed an ORR of 58 percent (95% CI: 39.1, 75.5) with a CRR of 19 percent and a PRR of 39 percent. The median follow-up time was 28.7 months. Among the 18 responding patients, the median duration of response was not reached (range 0.0+ to 26.1+), with 80 percent of patients with a response of six months or longer and 70 percent of patients with a response of 12 months or longer.