Real-world study of pegylated interferon α-2a to treat mycosis fungoides/Sézary syndrome using time to next treatment as a measure of clinical benefit: an EORTC CLTG study.

BACKGROUND: Mycosis fungoides (MF) and Sézary syndrome (SS) are chronic malignant diseases that typically necessitate diverse strategies to achieve remission. Systemic interferon (IFN)-α (subtypes 2a and 2b) has been used to treat MF/SS since 1984; however, its production was recently stopped. The recombinant pegylated (PEG) form of IFN-α-2a remains the only alternative IFN treatment, although it has not been approved for use in MF/SS. OBJECTIVES: To assess the effectiveness and safety of PEG-IFN-α-2a in monotherapy and in combination with other treatments using time to next treatment (TTNT) as a measure of clinical therapeutic benefit in a real-world setting. METHODS: We conducted an international, multicentre retrospective study of patients with MF and SS (of any stage) treated with PEG-IFN-α-2a from July 2012 to February 2022. Patients were included across 11 centres in 10 countries. The primary endpoints were to determine the TTNT of PEG-IFN-α-2a and adverse events (AEs) in MF/SS. RESULTS: In total, 105 patients were included [mean (SD) age 61 (13.1) years]; 42 (40.0%) had stage IA-IIA and 63 (60.0%) had stage IIB-IVB disease. PEG-IFN-α-2a was combined with other therapies in 67 (63.8%) patients, most commonly with extracorporeal photopheresis (36%) and bexarotene (22%). Patients with stage I-IIA disease achieved an overall response rate (ORR) of 57%; the ORR in those with stage IIB-IVB disease was 51%. Combination treatment resulted in a median TTNT of 10.4 months (range 0.6-50.7) vs. 7.0 months (range 0.7-52.4) for those who received monotherapy (P < 0.01). Overall, the mean (SD) TTNT was 9.2 (10.6) months and the ORR was 53.3% (n = 56). A complete response was seen in 13% of patients and a partial response in 40%. AEs were described in 68.6% (n = 72) of patients. Flu-like symptoms (n = 28; 26.7%), lymphopenia (n = 24; 22.9%) and elevated liver function (n = 10; 9.5%) were the most frequently reported. Grade 3-4 AEs were reported in 23 (21.9%) patients, mostly related to myelosuppression. CONCLUSIONS: PEG-IFN-α-2a for MF/SS resulted in an ORR of 53.3% and a mean (SD) TTNT of 9.2 (10.6) months. Combination regimens were superior to monotherapy and doses of 180 µg PEG-IFN-α-2a weekly were related to a higher ORR.

Mycosis fungoides (MF) and Sézary syndrome (SS) are rare types of cancers of the lymphatic system (lymphomas). They result in patches, plaques and/or tumours on the skin that usually need a combination of treatments to be controlled. A drug called interferon alpha (IFN-α) has been used to treat cutaneous lymphomas since 1984, but its production was recently stopped, so another form of it called 'recombinant pegylated IFN α-2a' (PEG-IFN-α-2a) is the only alternative IFN treatment, even though it has not been formally approved for MF/SS. The lack of studies on PEG-IFN-α-2a for MF/SS treatment has meant that its use can vary between institutions. This study aimed to investigate the effectiveness, the safety and how well PEG-IFN-α-2a is tolerated as single treatment or in combination with other MF/SS treatments. We carried out a study of patients with MF/SS treated with PEG-IFN-α-2a between July 2012 and February 2022. In total, 105 patients were included from 10 countries. We found that 53% of the patients responded to PEG-IFN-α-2a treatment. We also found that doses of 180 µg weekly, as well as combining PEG-IFN-α-2a with other treatments, resulted in higher response rates and a longer time until a new treatment needed to be added. However, at least one adverse event occurred in 69% of patients. The most common were flu-like symptoms, a reduction in the number of white blood cells and increased liver function. Severe adverse events occurred in 21% of the patients, mostly related to a reduction in the number of blood cells. Overall, our study findings suggest that PEG-IFN-α-2a is an effective and generally well-tolerated option among the treatments for MF/SS, with patients experiencing a better response when it was used as part of a combination therapy and on doses of 180 µg weekly.

The efficacy of immune checkpoint blockade for melanoma in-transit with or without nodal metastases - A multicenter cohort study.

PURPOSE: Guidelines addressing melanoma in-transit metastasis (ITM) recommend immune checkpoint inhibitors (ICI) as a first-line treatment option, despite the fact that there are no efficacy data available from prospective trials for exclusively ITM disease. The study aims to analyze the outcome of patients with ITM treated with ICI based on data from a large cohort of patients treated at international referral clinics. METHODS: A multicenter retrospective cohort study of patients treated between January 2015 and December 2020 from Australia, Europe, and the USA, evaluating treatment with ICI for ITM with or without nodal involvement (AJCC8 N1c, N2c, and N3c) and without distant disease (M0). Treatment was with PD-1 inhibitor (nivolumab or pembrolizumab) and/or CTLA-4 inhibitor (ipilimumab). The response was evaluated according to the RECIST criteria modified for cutaneous lesions. RESULTS: A total of 287 patients from 21 institutions in eight countries were included. Immunotherapy was first-line treatment in 64 (22%) patients. PD-1 or CTLA-4 inhibitor monotherapy was given in 233 (81%) and 23 (8%) patients, respectively, while 31 (11%) received both in combination. The overall response rate was 56%, complete response (CR) rate was 36%, and progressive disease (PD) rate was 32%. Median PFS was ten months (95% CI 7.4-12.6 months) with a one-, two-, and five-year PFS rate of 48%, 33%, and 18%, respectively. Median MSS was not reached, and the one-, two-, and five-year MSS rates were 95%, 83%, and 71%, respectively. CONCLUSION: Systemic immunotherapy is an effective treatment for melanoma ITM. Future studies should evaluate the role of systemic immunotherapy in the context of multimodality therapy, including locoregional treatments such as surgery, intralesional therapy, and regional therapies.