Effects of an immunosuppressive therapy on the efficacy of immune checkpoint inhibition in metastatic melanoma - An analysis of the prospective skin cancer registry ADOREG

BACKGROUND

The impact of immunosuppressive therapy (IST) on immune-checkpoint inhibition (ICI) is unclear.

METHODS

Patients with unresectable advanced melanoma (MM) treated with ICI in the years 2011-2020 were identified from the prospective multicenter German skin cancer registry ADOREG. Patients with IST within 60 days before, or within 30 days after start of ICI were compared to patients without IST. End points were disease control rate (DCR), overall survival (OS) and progression-free survival (PFS) determined by Kaplan-Meier method. Prognostic factors were evaluated in a Cox regression model.

RESULTS

Of 814 patients treated with ICI, 73 (9%) received concomitant IST, mainly steroids. Patients with brain metastases (BM) received IST more frequently (n = 34/130 patients; 26%), than patients without BM (39/684 patients; 6%). In patients without BM, IST initiated before, but not IST initiated after start of ICI was significantly associated with worse PFS (univariate hazard ratio (HR) 2.59, 95% confidence interval (95%-CI) 1.07-6.28, p = 0.035; multivariate HR 3.48, 95%-CI 1.26-9.6, p = 0.016). There was no association between IST and OS or DCR. In patients with BM, IST initiated before, but not after start of ICI was significantly associated with worse OS (univariate HR 2.06, 95%-CI 1.07-3.95, p = 0.031; multivariate HR 5.91, 95%-CI 1.74-20.14, p = 0.004). There was no association between IST and PFS or DCR.

CONCLUSION

Patients receiving IST 60 days before start of ICI showed a tendency to an impaired therapy outcome. IST initiated within 30 days after start of ICI, mainly due to early side effects, did not affect the efficacy of ICI therapy.

COMBI-r: A Prospective, Non-Interventional Study of Dabrafenib Plus Trametinib in Unselected Patients with Unresectable or Metastatic BRAF V600-Mutant Melanoma

Combined BRAF/MEK-inhibition constitutes a relevant treatment option for BRAF-mutated advanced melanoma. The prospective, non-interventional COMBI-r study assessed the effectiveness and tolerability of the BRAF-inhibitor dabrafenib combined with the MEK-inhibitor trametinib in patients with advanced melanoma under routine clinical conditions. Progression-free survival (PFS) was the primary objective, and secondary objectives included overall survival (OS), disease control rate, duration of therapy, and the frequency and severity of adverse events. This study enrolled 472 patients at 55 German sites. The median PFS was 8.3 months (95%CI 7.1-9.3) and the median OS was 18.3 months (14.9-21.3), both tending to be longer in pre-treated patients. In the 147 patients with CNS metastases, PFS was similar in those requiring corticosteroids (probably representing symptomatic patients, 5.6 months (3.9-7.2)) compared with those not requiring corticosteroids (5.9 months (4.8-6.9)); however, OS was shorter in patients with brain metastases who received corticosteroids (7.8 (6.3-11.6)) compared to those who did not (11.9 months (9.6-19.5)). The integrated subjective assessment of tumor growth dynamics proved helpful to predict outcome: investigators' upfront categorization correlated well with time-to-event outcomes. Taken together, COMBI-r mirrored PFS outcomes from other prospective, observational studies and confirmed efficacy and safety findings from the pivotal phase III COMBI-d/-v and COMBI-mb trials.

Treatment management for BRAF-mutant melanoma patients with tumor recurrence on adjuvant therapy: a multicenter study from the prospective skin cancer registry ADOREG

BACKGROUND

Adjuvant therapy with immune-checkpoint inhibitors (CPI) or BRAF/MEK-directed targeted therapy (TT) improves recurrence-free survival (RFS) for patients with advanced, BRAFV600-mutant (BRAFmut) resected melanoma. However, 40% of these patients will develop distant metastases (DM) within 5 years, which require systemic therapy. Little data exist to guide the choice of upfront adjuvant therapy or treatment management upon DM. This study evaluated the efficacy of subsequent treatments following tumor recurrence upon upfront adjuvant therapy.

METHODS

For this multicenter cohort study, we identified 515 BRAFmut patients with resected stage III melanoma who were treated with PD-1 inhibitors (anti-PD1) or TT in the adjuvant setting. Disease characteristics, treatment regimens, details on tumor recurrence, subsequent treatment management, and survival outcomes were collected within the prospective, real-world skin cancer registry ADOReg. Primary endpoints included progression-free survival (PFS) following DM and best tumor response to first-line (1L) treatments.

RESULTS

Among 515 eligible patients, 273 patients received adjuvant anti-PD1 and 242 adjuvant TT. At a median follow-up of 21 months, 54.6% of anti-PD1 patients and 36.4% of TT patients recurred, while 39.6% (anti-PD1) and 29.3% (TT) developed DM. Risk of recurrence was significantly reduced in patients treated with TT compared with anti-PD1 (adjusted HR 0.52; 95% CI 0.40 to 0.68, p<0.001). Likewise, median RFS was significantly longer in TT-treated patients (31 vs 17 months, p<0.001). Patients who received TT as second adjuvant treatment upon locoregional recurrence had a longer RFS2 as compared with adjuvant CPI (41 vs 6 months, p=0.009). Patients who recurred at distant sites following adjuvant TT showed favorable response rates (42.9%) after switching to 1L ipilimumab+nivolumab (ipi+nivo). Patients with DM during adjuvant anti-PD1 achieved response rates of 58.7% after switching to 1L TT and 35.3% for 1L ipi+nivo. Overall, median PFS was significantly longer in patients who switched treatments for stage IV disease (median PFS 9 vs 5 months, p=0.004).

CONCLUSIONS

BRAFmut melanoma patients who developed DM upon upfront adjuvant therapy achieve favorable tumor control and prolonged PFS after switching treatment modalities in the first-line setting of stage IV disease. Patients with locoregional recurrence benefit from complete resection of recurrence followed by a second adjuvant treatment with TT.