On Location
Conference Coverage
UPDATES IN MALIGNANT HEMATOLOGY
Attendees at the plenary session
SH Clinical News was
on site at this year’s
American Society
of Clinical Oncology
Annual Meeting in Chicago to
bring you the latest advances
in malignant hematology presented at the meeting, including
updates from late-phase clinical
trials in leukemia, lymphoma,
and myeloma.
Here, we present highlights
from the meeting, including new
information about thrombosis
risk in myeloma, improvements
to the FDA’s “compassionate
use” program, and a look at
venetoclax combinations in older
patients with acute myeloid
leukemia.
Pacritinib for Myelofibrosis:
Follow-Up from PERSIST-1
Results from the phase III PERSIST-1 study
presented at the 2015 American Society of Clinical
Oncology Annual (ASCO) Meeting showed that
the JAK2 inhibitor pacritinib led to more effective spleen volume reduction and better symptom
control in patients with myelofibrosis, compared
with best available treatment. Two analyses from
the PERSIST-1 trial presented at this year’s ASCO
Annual Meeting provide new data about the safety
and efficacy of pacritinib for myelofibrosis: one featuring 60-week follow-up data from the PERSIST-1
study1 and the other examining pacritinib in a
subset of patients with thrombocytopenia.2
As we reported earlier, the U.S. Food and Drug
Administration (FDA) pulled the investigational
new drug application for pacritinib in February
2016, halting the ongoing PERSIST-1 and PERSIST-2 clinical trials and affecting future planned
clinical trials. In their decision letter, the FDA
noted that the interim overall survival results
generated from the unblinded PERSIST-2 data
showed a detrimental effect on survival for patients
treated with pacritinib, consistent with the results
of PERSIST-1. Excess mortality also occurred in
pacritinib-treated patients compared with the
control arm in the PERSIST-1 trial after crossover
to the pacritinib arm.
Evaluating Duration of Response
In earlier results from the PERSIST-1 trial, which
compared daily oral pacritinib with best available
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ASH Clinical News
treatment (BAT; including erythropoietin-stimulating agents, immunomodulatory drugs, and hydroxyurea, but excluding ruxolitinib), a significantly
greater proportion of patients treated with pacritinib
achieved a ≥35 percent spleen volume reduction
(SVR) and ≥50 percent reduction in Total Symptom
Score (TSS) at 24 weeks.
At this year’s meeting, Ruben A. Mesa, MD, from
the Mayo Clinic in Scottsdale, Arizona, presented updated safety and efficacy data through 60-week followup, which confirmed that pacritinib led to durable
reductions in spleen volume and symptom burden.1
PERSIST-1 included 327 JAK2 inhibitor-naïve
patients who met the following criteria:
• Dynamic International Prognostic Scoring
System (DIPSS) status of intermediate-1,
intermediate-2, or high-risk myelofibrosis
• Absolute neutrophil count (ANC)
>500/µL
• Palpable splenomegaly ≥5 cm
• Baseline TSS ≥13
Patients were randomized 2:1 to receive daily
oral pacritinib 400 mg (n=220) or BAT (n=107).
Patients were allowed to crossover from BAT to
pacritinib after 24 weeks or upon disease progression prior to week 24.
July 2016