Multicentric EORTC retrospective study shows efficacy of brentuximab vedotin in patients who have mycosis fungoides and Sézary syndrome with variable CD30 positivity.

Background: Brentuximab vedotin (BV) was approved as a therapy for mycosis fungoides (MF) based on the ALCANZA trial. Little real-world data, however, are available.

Objectives: To evaluate the efficacy and safety of BV in patients with MF/Sézary Syndrome (SS) with variable CD30 positivity in a real-world cohort and to explore potential predictors of response.

Methods: Data from 72 patients with MF/SS across nine EORTC (European Organization for Research and Treatment of Cancer) centres were included. The primary endpoint was to evaluate the proportion of patients with: overall response (ORR), ORR lasting over 4 months (ORR4), time to response (TTR), response duration (RD), progression-free survival (PFS) and time to next treatment (TTNT). Secondary aims included a safety evaluation and the association of clinicopathological features with ORR, RD and TTNT.

Results: All 72 patients had received at least one systemic treatment. ORR was achieved in 45 of 67; ORR4 in 28 of 67 with a median TTR of 8 weeks [interquartile range (IQR) 5·5-14] and with a median RD of 9 months (IQR 3·4-14). Median PFS was 7 months (IQR 2-12) and median TTNT was 30 days (6-157·5). Patient response, RD, PFS and TTNT were not associated with any clinicopathological characteristics. In the MF group, patients with stage IIB/III vs. IV achieved longer PFS and had a higher percentage of ORR4. There was a statistically significant association between large-cell transformation and skin ORR (P = 0·03). ORR4 was more frequently achieved in patients without lymph node involvement (P = 0·04).

Conclusions: BV is an effective option for patients with MF/SS, including those with variable CD30 positivity, large-cell transformation, SS, longer disease duration and who have been treated previously with several therapies.