Federal regulators remain unconvinced by the evidence submitted for the drug, which is intended for use alongside Bristol Myers Squibb’s Opdivo. The FDA briefing released Tuesday explicitly notes that the Woburn, Massachusetts-based company has not provided an adequate, well-controlled investigation to substantiate effectiveness claims. These findings persist despite the company’s attempt to resolve previous rejections issued in July 2023 and April 2024.

At the core of the dispute is the clinical trial design, which lacked a control group for comparison. While Replimune representatives previously sought high-level intervention, arguing that the rejections hindered access for terminally ill patients, the FDA’s technical stance remains unchanged. The upcoming advisory committee meeting will offer independent experts a chance to weigh in on the data, though the agency is not obligated to follow their final recommendations when it reaches a target decision date of August 2.