By Vicki Moore, PhD

Higher Symptom Burden More Likely to Improve With MPN Treatment

Data from 2 clinical trials involving patients with myeloproliferative neoplasms (MPNs) revealed the importance of considering symptom burden in evaluating treatment efficacy and tolerability. The study results were published in The Lancet Haematology.

The analysis included data from the single-arm phase 2 MPN-RC 111 study (ClinicalTrials.gov Identifier: NCT01259817) and from the randomized, open-label phase 3 MPN-RC 112 study (ClinicalTrials.gov Identifier: NCT01258856). MPN-RC 111 evaluated clinical-hematologic response to pegylated interferon alfa-2a in patients who had hydroxyurea resistance or intolerance. MPN-RC 112 evaluated clinical-hematologic response to pegylated interferon alfa-2a in comparison with hydroxyurea in treatment-naïve patients who had high-risk essential thrombocythemia (ET) or polycythemia vera (PV).

This analysis made use of results from patient questionnaires including the Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF) and the European Organisation for the Research and Treatment of Cancer Core Quality of Life Questionnaire. The objective of the analysis was to analyze symptom burden with respect to both the clinical-hematologic response at 12-months and the baseline symptom burden.

Symptom burden was categorized as either high (total symptom score ≥20) or low (total symptom score <20). The researchers considered a clinically significant improvement in symptom burden to be an improvement of 50% or more in MPN-SAF total symptom score over 12 months for patients who had a nonzero total symptom score at baseline.

There were 114 patients analyzed from the MPN-RC 111 study (64 with ET, 50 with PV) and 166 patients (79 with ET, 87 with PV) from the MPN-RC 112 study. Among patients from the MPN-RC 111 study, 32% of complete responders and 20% of partial responders reported clinically significant improvements in symptom burden at 12 months.

For patients from the MPN-RC 112 study, among those treated with pegylated interferon alfa-2a, 19% of complete responders and 18% of partial responders reported a clinically significant improvement in symptom burden at 12 months. Of those treated with hydroxyurea, this outcome was reported in 27% of complete responders and 22% of partial responders.

Overall, responders — complete or partial — more often experienced a clinically significant improvement than did nonresponders (22% and 5%, respectively; P =.0003). However, the study investigators noted that most responders did not report a clinically significant improvement.

Additionally, patients who had a high symptom burden at baseline showed improvements in symptom burden at both 3 and 12 months, whether treated with pegylated interferon alfa-2a or hydroxyurea, with mean symptom score changes of -10.2 for pegylated interferon alfa-2a and -6.8 for hydroxyurea. Patients with low baseline symptom burden, however, experienced worse symptom burden at these time points. Mean symptom score changes were 3.2 with pegylated interferon alfa-2a and 3.4 with hydroxyurea for these patients.

“In summary, clinicians, researchers, and regulatory agencies should consider symptom burden and quality of life when evaluating treatment efficacy in patients with essential thrombocythaemia and polycythaemia vera,” they concluded.

Disclosures: Some authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.