A phase 2 study of INmune Bio’s TNF inhibitor in Alzheimer’s disease has missed its primary endpoint, wiping 60% off the biotech share price.
As INmune CEO Raymond Tesi, M.D., said on an earnings call last month, the company designed the phase 2 trial to show “what happens in Alzheimer's disease when you properly target neuroinflammation?” The answer, assuming INmune properly targeted neuroinflammation, appears to be “not much,” at least in the overall population.
After six months of treatment, patients on INmune’s XPro drug candidate did no better than their peers on placebo on the EMACC measure of cognition in early Alzheimer’s. The result meant the trial missed its primary endpoint. The study also missed its secondary endpoints, Tesi said on a call with analysts Monday.
INmune’s press release lacks data on how XPro performed in the 200-patient modified intent-to-treat population. Instead, the biotech dug into how the drug candidate fared in a predefined population of 100 amyloid-positive early Alzheimer’s patients with two or more biomarkers of inflammation.
The biotech reported a clinical benefit of XPro over placebo on EMACC and the secondary endpoint neuropsychiatric inventory in the subpopulation. INmune also linked XPro to a change in the biomarker pTau217 in the 100 patients. Effect sizes exceeded the 0.2 that Judith Jaeger, Ph.D,, a consultant to INmune on the trial, said in a statement is considered preliminary evidence of potential efficacy in early-phase trials.
“When a therapy consistently meets the 0.2 benchmark across multiple parameters (clinical and biological), confidence in the validity of the observed effects increases, indicating a therapy is worth advancing,” Jaeger said.
The question of who will pay to advance XPro remains unanswered. Tesi told analysts that “XPro appears to be effective in an easily defined and commercially relevant patient population with early Alzheimer's disease and we see a path forward.” But the CEO also recognized “there is work to be done and that work will require financial resources.”
INmune ended March with $19.3 million and closed a $19 million financing this week. Investors showed little enthusiasm for XPro after seeing the data, sending INmune shares down 59% to $2.17 in premarket trading. Needing financial support, Tesi said the biotech plans to explore partnering opportunities as it prepares to present additional analyses of the data and talk to the FDA.