Photo courtesy of UCLA
LUGANO—The PD-1 checkpoint inhibitor nivolumab produces rapid, durable, and, in some cases, “dramatic” responses in Hodgkin lymphoma (HL), according to a speaker at the 13th International Congress on Malignant Lymphoma.
The drug has also produced durable responses in follicular lymphoma (FL), cutaneous T-cell lymphoma (CTCL), and peripheral T-cell lymphoma (PTCL), although patient numbers for these malignancies are small.
John Timmerman, MD, of the University of California, Los Angeles, presented these results from a phase 1 study of patients with relapsed or refractory lymphoid malignancies and chronic HL (abstract 010).
Bristol-Myers Squibb and Ono Pharmaceutical Company are sponsors of the trial.
Original results of the study, with a data cutoff of June 2014, were reported at ASH 2014, with 40 weeks of median follow-up.
The update presented at 13-ICML, with a data lock in April 2015, includes an additional 10 months of data, for a median follow-up of 76 weeks.
Investigators enrolled 105 patients in this dose-escalation study to receive nivolumab at 1 mg/kg, then 3 mg/kg, every 2 weeks for 2 years.
Twenty-three patients had HL. Thirty-one had B-cell non-Hodgkin lymphoma (NHL), including 11 with FL and 10 with diffuse large B-cell lymphoma (DLBCL).
Twenty-three patients had T-cell NHL, including 5 with PTCL and 13 with CTCL/mycosis fungoides (MF). Twenty-seven patients had multiple myeloma (MM), and 1 had chronic myeloid leukemia.
Patients were heavily pretreated. Seventy-eight percent of HL patients and 26% of T-NHL patients had prior brentuximab vedotin. And 78% (HL), 14% (B-NHL), 9% (T-NHL), and 56% (MM) of patients had a prior autologous transplant.
The median number of prior therapies was 5 (range, 2-15) for HL patients and ranged from 1 to 16 for all patients.
The study’s primary endpoint was safety and tolerability, and the secondary endpoint was efficacy.
Safety and tolerability
Ninety-seven percent of patients had an adverse event, 69% of them related to study treatment and 21% of them treatment-related grade 3-4 events.
Fifteen patients (14%) discontinued treatment due to a related adverse event, including 3 with pneumonitis and 1 each with enteritis, stomatitis, pancreatitis, rash, conjunctivitis, sepsis, diplopia, myositis, neutropenia, myelodysplastic syndrome, increased creatinine phosphokinase, and peripheral neuropathy.
“Immune-related adverse events were generally seen early on and generally of low grade,” Dr Timmerman said. “However, it is notable that there were several grade 3 immune-related adverse events that can be seen as far as 6 months out after the start of therapy.”
These included skin, gastrointestinal, and pulmonary events. Most immune-related adverse events (83%) were resolved using protocol-prescribed procedures.
Efficacy
The overall response rate was 87% for HL, 36% for DLBCL, 40% for FL, 15% for CTCL/MF, 40% for PTCL, and 4% for MM.
Dr Timmerman pointed out that, since ASH, 2 additional conversions from partial response (PR) to complete response (CR) occurred in patients with HL. To date, 6 of 23 HL patients have achieved a CR and 14 a PR.
In B-cell NHL, there were additional conversions from PR to CR in DLBCL, while responses remained the same in FL and in the 4 responders with T-cell lymphomas.
“Intriguingly, there has been 1 late CR in the multiple myeloma cohort, which previously had shown no responses,” Dr Timmerman said.
Durability of response
This study suggests PD-1 blockade can produce durable responses in hematologic malignancies, as it does in melanoma and renal cell carcinoma.
In HL, the median response duration at a median follow-up of 86 weeks has not yet been reached, and half (n=10) of the responses are still ongoing.
In FL, CTCL, and PTCL, the median response duration has not been reached at a median follow-up of 81, 43, and 31 weeks, respectively. Of note, there are ongoing responses in at least half of patients in these tumor types.
In HL, none of the 6 patients in CR has progressed, although there have been some progressions in the PR group.
The rapidity of responses is also notable, Dr Timmerman said.
“[I]t’s very interesting that some patients have resolution of symptoms and improvement of symptoms within even 1 day of starting nivolumab therapy,” he said.
And responses to nivolumab in HL “can be very dramatic,” he added, as illustrated in the following case from the Mayo Clinic.
A patient with multiple sites of bulky FDG-avid tumors was scheduled to enter hospice. But first, he entered the nivolumab trial. Within 6 weeks of initiating treatment, he had achieved a near-CR. This response has been maintained for 2 years.
“The occurrence of very durable responses in the PR and CR groups has led us to question whether patients should go on to allogeneic stem cell transplantation after achieving responses with nivolumab or, rather, continue on nivolumab as long as their response remains,” Dr Timmerman said.
He added that an international, phase 2 trial in HL is underway and is accruing briskly.
Nivolumab was awarded breakthrough designation by the US Food and Drug Administration last year. Breakthrough designation is intended to expedite the development and review of drugs for serious or life-threatening conditions.
