PRIMO Study for R/R Peripheral T-cell Lymphoma Meets Enrollment Milestone

The target enrollment of 157 adult patients with relapsed or refractory peripheral T-cell lymphoma has been met in the phase 2 PRIMO clinical trial, according to a press release by the developer, Secura Bio, Inc.¹

PRIMO is a global, multicenter, open-label, parallel cohort, phase 2 study exploring treatment with duvelisib (Copiktra), an oral PI3K inhibitor. Duvelisib has been granted fast track designation from the FDA for the treatment of patients with PTCL who have received at least 1 prior therapy. The drug was also granted orphan drug designation from the FDA for the treatment of T-cell lymphomas, but duvelisib is not currently indicated for the treatment of these diseases.

The PRIMO study was initiated to address the median overall survival (OS) shown with FDA-approved therapies for the treatment of relapsed/refractory PTCL, which is less than 6 months. Moreover, the overall response rates (ORRs) associated with these therapies is less than 30%. Based on the success of duvelisib in relapsed/refractory follicular lymphoma and chronic lymphocytic leukemia, investigators hypothesized that the agent may also be beneficial for patients with relapsed/refractory PTCL.²

Objective response rate is the primary end point of the study, and as secondary end points, the study is investigating the number of patients with treatment-emergent adverse events (AEs), duration of response (DOR), progression-free survival (PFS), disease control rate, OS, and the percentage of patients who received the optimal dose of duvelisib.

Interim results from 78 patients enrolled in the study were presented during the 63rd American Society of Hematology Annual Meeting & Exposition. The population included has a median age of 66.5 years (range, 21-92), and received a median of 3 prior lines of therapy (range, 1-17). Treatment with duvelisib achieved an ORR of 50% in these patients and a 32.1% complete response rate, according to independent review committee assessment. The median time to response was 53 days (range, 15-114), and the median DOR was 233 days (range, 1+ to 420+).³

When ORRs were assessed by subgroup, the ORR was highest for patients with the angioimmunoblastic T‐cell lymphoma (66.7%) and lowest in patient with the anaplastic large cell lymphoma (9.1%).

Duvelisib also achieved a 107-day median PFS during the interim analysis (95% CI, 57-188).

At the time of data cutoff, 18% of patients remained on treatment while 47.4% discontinued treatment. Of those who discontinued, AEs were the cause for 19.2%. The most common grade 3 or higher AEs were neutropenia (38.5%), alanine aminotransferase/aspartate aminotransferase increased (24.4%/21.8%), rash (7.7%), lymphocyte count decreased (7.7%), and sepsis (6.4%). Death-causing evens believed to be related to duvelisib included pneumonitis, Epstein-Barr-associated lymphoproliferative disorder, and sepsis.

With the study fully enrolled, patients in the expansion phase will be treated with duvelisib 75 mg twice daily (BID) for 2 cycles followed by 25 mg BID at 1 of 25 United Stated locations including California, Georgia, Illinois, Kentucky, Maryland, Massachusetts, Missouri, New York, North Carolina, Ohio, Pennsylvania, and Texas. The study is also being conducted in Germany, Italy, and the United Kingdom.

"Secura Bio is dedicated to the development of Copiktra for the treatment of T-cell malignancies because these patients often have limited therapeutic options and generally poor outcomes. In addition to the treatment of relapsed/refractory PTCL patients, we are exploring a wide range of development options for T-cell malignancies, including earlier line use as a single-agent or in combinations with other mechanisms of action," said Dr. David Cohan, chief medical Ooficer of Secura Bio, in the press release.

_References:

_{1. Secura Bio announces final patient enrolled in the COPIKTRA® (duvelisib) (PRIMO) study in relapsed and refractory peripheral t-cell lymphoma. News release. February 9, 2022. Accessed February 9, 2022. https://prn.to/35PfHFN}

_{2. Brammer JE, Zinzani PL, Zain J, et al. 2456 Duvelisib in patients with relapsed/refractory peripheral t-cell lymphoma from the phase 2 primo trial: results of an interim analysis. Presented at: 2021 American Society of Hematology Annual Meeting & Exposition; December 11-14, 2021; Atlanta, GA. Abstract 2456.}

_{3. A study of duvelisib in patients with relapsed or refractory peripheral t cell lymphoma (PTCL). Clinicaltrials.gov Accessed February 9, 2022. https://bit.ly/3Lq0YSi}