Pooled analysis of 7.5 years data shows Imbruvica improves PFS and increases chance of complete response in mantle cell lymphoma.- AbbVie

AbbVie announced results of a 7.5-year pooled analysis showing earlier treatment with Imbruvica (ibrutinib) monotherapy compared to later lines of therapy (LOT) extended progression-free survival (PFS) and increased the likelihood of a complete response (CR) in patients with relapsed/refractory (R/R) mantle cell lymphoma (MCL) � demonstrating that some patients achieved a disappearance of any signs of disease.

The updated pooled analysis includes three clinical trials: Phase II SPARK, Phase III RAY and Phase II PCYC-1104. Patients achieving a CR with Imbruvica had a strong response, with a median duration of therapy longer than 5.5 years. Results showed overall median PFS on Imbruvica was 12.5 months (9.8 � 16.6) compared to median TTNT on the prior regimen of 10.9 months (9.1-12.6). PFS for patients who received Imbruvica was longer than TTNT on the prior regimen for 50 percent of patients; for 27 percent of patients, PFS was longer than TTNT on the prior regimen by 12 months or more.

At five years, PFS rate was 19 percent and overall survival (OS) rate was 41 percent. In patients with one prior LOT, median PFS was 25.4 months (17.5 � 51.8) and OS was 61.6 months (36.0 � not estimable [NE]). In patients with a CR, median PFS was 67.7 months (51.7 � NE) and OS was not reached (NE-NE). Additionally, of the 99 patients who received Imbruvica in second-line, 43 percent had early frontline POD and 57 percent of them had late frontline POD. In patients with early frontline POD, median PFS with Imbruvica (13.8 months) was similar to median frontline TTNT (14.0 months); median duration of response (DOR) and OS on Imbruvica were 22.1 and 23.5 months, respectively. In patients with late frontline POD, median PFS with Imbruvica (57.5 months) was longer than median frontline TTNT (42.2 months); median DOR and OS on Imbruvica were not reached.

With up to 92 months of follow-up, 81.6 percent of patients had Grade 3 or higher treatment-emergent adverse events (TEAEs) and 64.9 percent had serious adverse events (SAEs). The most common Grade 3 or higher TEAEs were neutropenia (17 percent), pneumonia (13.5 percent) and thrombocytopenia (12.4 percent). The most common SAEs were pneumonia (13.2 percent), atrial fibrillation (5.7 percent), and dyspnea (4.3 percent). These results were presented at the American Society of Hematology (ASH) Annual Meeting.

Comment: Simon Rule, M.D., Professor in Haematology, Peninsula Medical School, University of Plymouth, United Kingdom: "These extended follow-up results from the pooled analysis of ibrutinib compared to prior regimens are very encouraging for patients with relapsed or refractory MCL � as they showed treatment with ibrutinib at first relapse versus later lines of therapy resulted in a median progression-free survival of longer than two years."