Seven deaths and five respiratory-related, treatment-emergent adverse events in a group of 40 aged and very unwell cancer patients rang alarm bells for ADC Therapeutics SA. The company has voluntarily paused enrollment in its phase II Lotis-9 study of Zynlonta (loncastuximab tesirine-lpyl) and rituximab (Lonca-R) for treating previously untreated diffuse large B-cell lymphoma in those who are considered frail or unfit.