Starting IST Before ICI Treatment May Impact PFS, OS in Advanced Melanoma

Receiving immunosuppressive therapy (IST) before starting immune checkpoint inhibitor (ICI) treatment may negatively affect survival outcomes in patients with advanced melanoma, according to research published in the European Journal of Cancer.

Researchers found that starting IST in the 60 days before ICI initiation was associated with worse progression-free survival (PFS) in patients without brain metastasis and worse overall survival (OS) in patients with brain metastasis.

For this study, researchers examined data from 814 patients with unresectable advanced melanoma who were enrolled in the prospective German skin cancer registry ADOREG. All patients had received an ICI as first-line treatment between 2011 and 2020.

The researchers compared outcomes for patients who received IST up to 60 days before ICI initiation (n=26), those who received IST up to 30 days after ICI initiation (n=47), and those who did not receive IST (n=741).

The researchers evaluated patients with and without brain metastases separately.

Results in Patients Without Brain Metastases

Of the 684 patients without brain metastases, 645 did not receive IST, 7 received IST before starting ICI treatment, and 32 received IST after starting ICI therapy. The median follow-up was 12 months.

The disease control rate (DCR) was 40% in patients who received IST before starting ICI therapy, 44% in patients who received IST after starting ICI treatment, and 37% in those who did not receive IST (P =.795).

The median PFS was 2 months in patients who received IST before ICI therapy, 16 months in patients who received IST after, and 6 months in those who did not receive IST (P =.046).

The median OS was 22 months in patients who received IST before ICI therapy, 39 months in patients who received IST after, and 35 months in those who did not receive IST (P =.784).

In a multivariate analysis, starting IST before ICI treatment was significantly associated with worse PFS (hazard ratio [HR], 3.48; 95% CI, 1.26-9.6, P =.016), but there were no significant associations between IST and OS or DCR.

Results in Patients With Brain Metastases

Of the 130 patients with brain metastases, 96 did not receive IST, 19 received IST before starting ICI treatment, and 15 received IST after starting ICI therapy. The median follow-up was 7 months.

The DCR was 21% in patients who received IST before starting ICI therapy, 33% in patients who received IST after starting ICI treatment, and 32% in those who did not receive IST (P =.720).

The median PFS was 5 months in patients who received IST before ICI therapy, 3 months in patients who received IST after, and 6 months in those who did not receive IST (P =.879).

The median OS was 8 months in patients who received IST before ICI therapy, 16 months in patients who received IST after, and 36 months in those who did not receive IST (P =.067).

In a multivariate analysis, starting IST before ICI treatment was significantly associated with worse OS (HR, 5.91; 95% CI, 1.74-20.14; P =.004), but there were no significant associations between IST and PFS or DCR.

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

This article originally appeared on Cancer Therapy Advisor