ICI Rechallenge Possible for Patients With Cancer With Proper Toxicity Monitoring

Resuming therapy with an immune checkpoint inhibitor (ICI) could be an option for certain patients with cancer, as long as appropriate monitoring and standard therapy algorithms are used to detect and treat toxicities, findings from an observational study suggest (JAMA Oncol. 2020 Apr 16. Epub ahead of print).

“Limited information is available on the safety of a rechallenge with an [ICI] after an immune-related adverse event (irAE),” explained Charles Dolladille, MD, MSc, University of Caen Normandy, France, and colleagues, who sought to establish the recurrence rate of the same irAE that prompted discontinuation of ICI therapy after an ICI rechallenge in patients with cancer. They also wanted to explore the clinical features tied to such recurrences.

Using a World Health Organization database, Dr Dolladille et al conducted a cross-sectional, pharmacovigilance cohort study of individual case reports from >130 countries between 1967 and 2019.

They specifically focused on cases in which ICI use was associated with at least 1 irAE. The main end point of the study was the recurrence rate of the initial irAE following an ICI rechallenge. The secondary end points included factors tied to recurrence after a rechallenge among informative rechallenges, the frequency of recurrence based on ICI regimen, and the rate at which different irAEs occur post-rechallenge.

Ultimately, Dr Dolladille et al identified 24,079 irAE cases related to at least 1 ICI. Among 6123 irAEs related to ICI rechallenge, 452 (7.4%) were informative, and they observed 130 (28.8%) initial irAE recurrences (95% CI, 24.8-33.1).

Compared with other irAEs, colitis (reporting odds ratio [OR], 1.77; 95% CI, 1.14-2.75; P = .01), hepatitis (reporting OR, 3.38; 95% CI, 1.31-8.74; P = .01), and pneumonitis (reporting OR, 2.26; 95% CI, 1.18-4.32; P = .01) were tied to a higher rate of recurrence during rechallenge, whereas adrenal events were tied to a lower recurrence rate (reporting OR, 0.33; 95% CI, 0.13-0.86; P = .03).

“This cohort study found a 28.8% recurrence rate of the same irAE associated with the discontinuation of ICI therapy after a rechallenge with the same ICI,” Dr Dolladille and colleagues said.

“Resuming ICI therapy could be considered for select patients, with appropriate monitoring and use of standard treatment algorithms to identify and treat toxic effects,” they concluded.—Hina Porcelli