Nivolumab for long-term treatment of cHL after auto-HSCT
SD was the best response for 19% of all patients, 24% of patients in cohort A, 21% in cohort B, and 15% in cohort C.
In post-hoc analyses, responses were similar irrespective of BV treatment sequence.
The median duration of response was 17 months overall, 20 months for cohort A, 16 months for cohort B, and 15 months for cohort C.
The median duration of response in patients with a CR was 20 months overall and for cohorts A and B, but it was 15 months for cohort C.
The median duration of response in patients with a PR was 13 months overall, 17 months for cohort A, 11 months for cohort B, and 13 months for cohort C.
Survival
The median PFS for all patients was 15 months (range, 11-19). The median PFS was 22 months (range, 19-not reached) for patients who achieved a CR, 15 months (range, 11-19) for those who achieved a PR, and 11 months (range, 6-18) for those who had SD.
The median PFS was 18 months (range, 11-22) for patients in cohort A, 15 months (range, 11-20) for cohort B, and 12 months (range, 11-18) for cohort C.
The median overall survival (OS) has not been reached in any of the cohorts. The 12-months OS is 92% overall, 93% in cohort A, 95% in cohort B, and 90% in cohort C.
Patient status after extended follow-up
Forty percent of all patients were still on treatment after extended follow-up, as were 48% of patients in cohort A, 40% in cohort B, and 35% in cohort C.
The most common reason for stopping treatment was disease progression—25% of cohort A, 28% of cohort B, and 24% of cohort C.
Patients also stopped treatment due to nivolumab-related toxicity—5% in cohort A, 11% in cohort B, and 7% in cohort C. Three percent, 1%, and 1%, respectively, stopped due to AEs unrelated to nivolumab.
Three percent of patients in cohort C stopped because they had attained the maximum clinical benefit, and 8% in cohort C completed treatment. This includes 7 patients who discontinued treatment because they were in CR for 1 year.
None of the patients in cohort A or B discontinued because they attained the maximum clinical benefit or because they completed treatment.
Eight percent of patients in cohort A, 10% in cohort B, and 17% in cohort C discontinued so they could proceed to HSCT.
Outcomes after allo-HSCT
Forty-four patients received allogeneic (allo-) HSCT after nivolumab. The median post-HSCT follow-up was 5.5 months (range, 0-19), and the median time from last dose of nivolumab to allo-HSCT was 1.6 months (range, 0.5-13.5).
At 100 days, the rate of grade 2-4 acute graft-vs-host disease (GVHD) was 27%. The rate of grade 3-4 acute GVHD was 17%, and the rate of chronic GVHD was 10%. At 6 months, the rates were 30%, 20%, and 15%, respectively.
The incidence of transplant-related mortality was 13% at 100 days and at 6 months.
“While there are risks, potentially, for acute GVHD and transplant-related mortality, these aren’t necessarily significantly different from what we’ve seen from other historical publications,” Dr Fanale said.
She cited data showing that the 100-day incidence of acute GVHD in cHL patients who underwent allo-HSCT ranges from 26% to 60%, and the incidence of transplant-related mortality in these patients ranges from 6% to 28%. 
