Efficacy with romidepsin
Among all evaluable PTCL patients in the romidepsin arm, the ORR was 59% (16/27), and the CR rate was 33% (9/27).
Responses occurred in seven patients with PTCL not otherwise specified (NOS), six with angioimmunoblastic T-cell lymphoma (AITL), one with hepatosplenic T-cell lymphoma, one with aggressive epidermotropic CD8+ T-cell lymphoma, and one with primary cutaneous PTCL.
CRs occurred in five patients with AITL and four with PTCL-NOS. Six patients who achieved a CR went on to transplant.
Among evaluable CTCL patients in the romidepsin arm, the ORR was 45% (5/11), and there were no CRs. Responses occurred in three patients with mycosis fungoides and two with Sézary syndrome.
The median progression-free survival was 5.41 months in CTCL patients and 6.72 months in PTCL patients.
Efficacy with bortezomib
Among evaluable PTCL patients in the bortezomib arm, the ORR was 44% (7/16), and the CR rate was 25% (4/16).
Responses occurred in three patients with AITL and four with PTCL-NOS. CRs occurred in two patients with each subtype.
Among evaluable CTCL patients in the bortezomib arm, the ORR was 27% (4/15), and there were no CRs. Responses occurred in one patient with mycosis fungoides and three with Sézary syndrome. One CTCL patient went on to transplant.
The median progression-free survival was 4.56 months among CTCL patients and 4.39 months in PTCL patients.
Safety
Dr. Mehta-Shah said both combinations were considered safe and well tolerated. However, there was a grade 5 adverse event (AE) – Stevens-Johnson syndrome – that occurred in the bortezomib arm and was considered possibly related to treatment.
Grade 3/4 AEs observed in the 31 patients treated at the MTD in the romidepsin arm were transaminase increase (n = 7), diarrhea (n = 6), hyponatremia (n = 4), neutrophil count decrease (n = 10), and platelet count decrease (n = 3).
Grade 3/4 AEs observed in the 23 patients treated at the MTD in the bortezomib arm were transaminase increase (n = 2) and neutrophil count decrease (n = 5).
Grade 3/4 transaminitis seemed to be more common among patients who received duvelisib alone during the lead-in phase, Dr. Mehta-Shah said.
Among patients treated at the MTD in the romidepsin arm, grade 3/4 transaminitis occurred in four patients treated during the lead-in phase and three who began receiving romidepsin and duvelisib together. In the bortezomib arm, grade 3/4 transaminitis occurred in two patients treated at the MTD, both of whom received duvelisib alone during the lead-in phase.
Based on these results, Dr. Mehta-Shah and her colleagues are planning to expand the romidepsin arm to an additional 25 patients. By testing the combination in more patients, the researchers hope to better understand the occurrence of transaminitis and assess the durability of response.
This study is supported by Verastem. Dr. Shah reported relationships with Celgene, Kyowa Kirin, Bristol-Myers Squibb, Verastem, and Genentech.
The T-cell Lymphoma Forum is held by Jonathan Wood & Associates, which is owned by the same company as this news organization.